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1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * PACKET - implements raw packet sockets.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
11 *
12 * Fixes:
13 * Alan Cox : verify_area() now used correctly
14 * Alan Cox : new skbuff lists, look ma no backlogs!
15 * Alan Cox : tidied skbuff lists.
16 * Alan Cox : Now uses generic datagram routines I
17 * added. Also fixed the peek/read crash
18 * from all old Linux datagram code.
19 * Alan Cox : Uses the improved datagram code.
20 * Alan Cox : Added NULL's for socket options.
21 * Alan Cox : Re-commented the code.
22 * Alan Cox : Use new kernel side addressing
23 * Rob Janssen : Correct MTU usage.
24 * Dave Platt : Counter leaks caused by incorrect
25 * interrupt locking and some slightly
26 * dubious gcc output. Can you read
27 * compiler: it said _VOLATILE_
28 * Richard Kooijman : Timestamp fixes.
29 * Alan Cox : New buffers. Use sk->mac.raw.
30 * Alan Cox : sendmsg/recvmsg support.
31 * Alan Cox : Protocol setting support
32 * Alexey Kuznetsov : Untied from IPv4 stack.
33 * Cyrus Durgin : Fixed kerneld for kmod.
34 * Michal Ostrowski : Module initialization cleanup.
35 * Ulises Alonso : Frame number limit removal and
36 * packet_set_ring memory leak.
37 * Eric Biederman : Allow for > 8 byte hardware addresses.
38 * The convention is that longer addresses
39 * will simply extend the hardware address
40 * byte arrays at the end of sockaddr_ll
41 * and packet_mreq.
42 * Johann Baudy : Added TX RING.
43 * Chetan Loke : Implemented TPACKET_V3 block abstraction
44 * layer.
45 * Copyright (C) 2011, <lokec@ccs.neu.edu>
46 *
47 *
48 * This program is free software; you can redistribute it and/or
49 * modify it under the terms of the GNU General Public License
50 * as published by the Free Software Foundation; either version
51 * 2 of the License, or (at your option) any later version.
52 *
53 */
54
55#include <linux/types.h>
56#include <linux/mm.h>
57#include <linux/capability.h>
58#include <linux/fcntl.h>
59#include <linux/socket.h>
60#include <linux/in.h>
61#include <linux/inet.h>
62#include <linux/netdevice.h>
63#include <linux/if_packet.h>
64#include <linux/wireless.h>
65#include <linux/kernel.h>
66#include <linux/kmod.h>
67#include <linux/slab.h>
68#include <linux/vmalloc.h>
69#include <net/net_namespace.h>
70#include <net/ip.h>
71#include <net/protocol.h>
72#include <linux/skbuff.h>
73#include <net/sock.h>
74#include <linux/errno.h>
75#include <linux/timer.h>
76#include <asm/uaccess.h>
77#include <asm/ioctls.h>
78#include <asm/page.h>
79#include <asm/cacheflush.h>
80#include <asm/io.h>
81#include <linux/proc_fs.h>
82#include <linux/seq_file.h>
83#include <linux/poll.h>
84#include <linux/module.h>
85#include <linux/init.h>
86#include <linux/mutex.h>
87#include <linux/if_vlan.h>
88#include <linux/virtio_net.h>
89#include <linux/errqueue.h>
90#include <linux/net_tstamp.h>
91#include <linux/percpu.h>
92#ifdef CONFIG_INET
93#include <net/inet_common.h>
94#endif
95#include <linux/bpf.h>
96
97#include "internal.h"
98
99/*
100 Assumptions:
101 - if device has no dev->hard_header routine, it adds and removes ll header
102 inside itself. In this case ll header is invisible outside of device,
103 but higher levels still should reserve dev->hard_header_len.
104 Some devices are enough clever to reallocate skb, when header
105 will not fit to reserved space (tunnel), another ones are silly
106 (PPP).
107 - packet socket receives packets with pulled ll header,
108 so that SOCK_RAW should push it back.
109
110On receive:
111-----------
112
113Incoming, dev->hard_header!=NULL
114 mac_header -> ll header
115 data -> data
116
117Outgoing, dev->hard_header!=NULL
118 mac_header -> ll header
119 data -> ll header
120
121Incoming, dev->hard_header==NULL
122 mac_header -> UNKNOWN position. It is very likely, that it points to ll
123 header. PPP makes it, that is wrong, because introduce
124 assymetry between rx and tx paths.
125 data -> data
126
127Outgoing, dev->hard_header==NULL
128 mac_header -> data. ll header is still not built!
129 data -> data
130
131Resume
132 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
133
134
135On transmit:
136------------
137
138dev->hard_header != NULL
139 mac_header -> ll header
140 data -> ll header
141
142dev->hard_header == NULL (ll header is added by device, we cannot control it)
143 mac_header -> data
144 data -> data
145
146 We should set nh.raw on output to correct posistion,
147 packet classifier depends on it.
148 */
149
150/* Private packet socket structures. */
151
152/* identical to struct packet_mreq except it has
153 * a longer address field.
154 */
155struct packet_mreq_max {
156 int mr_ifindex;
157 unsigned short mr_type;
158 unsigned short mr_alen;
159 unsigned char mr_address[MAX_ADDR_LEN];
160};
161
162union tpacket_uhdr {
163 struct tpacket_hdr *h1;
164 struct tpacket2_hdr *h2;
165 struct tpacket3_hdr *h3;
166 void *raw;
167};
168
169static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
170 int closing, int tx_ring);
171
172#define V3_ALIGNMENT (8)
173
174#define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
175
176#define BLK_PLUS_PRIV(sz_of_priv) \
177 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
178
179#define PGV_FROM_VMALLOC 1
180
181#define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
182#define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
183#define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
184#define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
185#define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
186#define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
187#define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
188
189struct packet_sock;
190static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
191static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
192 struct packet_type *pt, struct net_device *orig_dev);
193
194static void *packet_previous_frame(struct packet_sock *po,
195 struct packet_ring_buffer *rb,
196 int status);
197static void packet_increment_head(struct packet_ring_buffer *buff);
198static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
199 struct tpacket_block_desc *);
200static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
201 struct packet_sock *);
202static void prb_retire_current_block(struct tpacket_kbdq_core *,
203 struct packet_sock *, unsigned int status);
204static int prb_queue_frozen(struct tpacket_kbdq_core *);
205static void prb_open_block(struct tpacket_kbdq_core *,
206 struct tpacket_block_desc *);
207static void prb_retire_rx_blk_timer_expired(unsigned long);
208static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
209static void prb_init_blk_timer(struct packet_sock *,
210 struct tpacket_kbdq_core *,
211 void (*func) (unsigned long));
212static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
213static void prb_clear_rxhash(struct tpacket_kbdq_core *,
214 struct tpacket3_hdr *);
215static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
216 struct tpacket3_hdr *);
217static void packet_flush_mclist(struct sock *sk);
218
219struct packet_skb_cb {
220 union {
221 struct sockaddr_pkt pkt;
222 union {
223 /* Trick: alias skb original length with
224 * ll.sll_family and ll.protocol in order
225 * to save room.
226 */
227 unsigned int origlen;
228 struct sockaddr_ll ll;
229 };
230 } sa;
231};
232
233#define vio_le() virtio_legacy_is_little_endian()
234
235#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
236
237#define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
238#define GET_PBLOCK_DESC(x, bid) \
239 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
240#define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
241 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
242#define GET_NEXT_PRB_BLK_NUM(x) \
243 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
244 ((x)->kactive_blk_num+1) : 0)
245
246static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
247static void __fanout_link(struct sock *sk, struct packet_sock *po);
248
249static int packet_direct_xmit(struct sk_buff *skb)
250{
251 struct net_device *dev = skb->dev;
252 netdev_features_t features;
253 struct netdev_queue *txq;
254 int ret = NETDEV_TX_BUSY;
255
256 if (unlikely(!netif_running(dev) ||
257 !netif_carrier_ok(dev)))
258 goto drop;
259
260 features = netif_skb_features(skb);
261 if (skb_needs_linearize(skb, features) &&
262 __skb_linearize(skb))
263 goto drop;
264
265 txq = skb_get_tx_queue(dev, skb);
266
267 local_bh_disable();
268
269 HARD_TX_LOCK(dev, txq, smp_processor_id());
270 if (!netif_xmit_frozen_or_drv_stopped(txq))
271 ret = netdev_start_xmit(skb, dev, txq, false);
272 HARD_TX_UNLOCK(dev, txq);
273
274 local_bh_enable();
275
276 if (!dev_xmit_complete(ret))
277 kfree_skb(skb);
278
279 return ret;
280drop:
281 atomic_long_inc(&dev->tx_dropped);
282 kfree_skb(skb);
283 return NET_XMIT_DROP;
284}
285
286static struct net_device *packet_cached_dev_get(struct packet_sock *po)
287{
288 struct net_device *dev;
289
290 rcu_read_lock();
291 dev = rcu_dereference(po->cached_dev);
292 if (likely(dev))
293 dev_hold(dev);
294 rcu_read_unlock();
295
296 return dev;
297}
298
299static void packet_cached_dev_assign(struct packet_sock *po,
300 struct net_device *dev)
301{
302 rcu_assign_pointer(po->cached_dev, dev);
303}
304
305static void packet_cached_dev_reset(struct packet_sock *po)
306{
307 RCU_INIT_POINTER(po->cached_dev, NULL);
308}
309
310static bool packet_use_direct_xmit(const struct packet_sock *po)
311{
312 return po->xmit == packet_direct_xmit;
313}
314
315static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
316{
317 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
318}
319
320static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
321{
322 const struct net_device_ops *ops = dev->netdev_ops;
323 u16 queue_index;
324
325 if (ops->ndo_select_queue) {
326 queue_index = ops->ndo_select_queue(dev, skb, NULL,
327 __packet_pick_tx_queue);
328 queue_index = netdev_cap_txqueue(dev, queue_index);
329 } else {
330 queue_index = __packet_pick_tx_queue(dev, skb);
331 }
332
333 skb_set_queue_mapping(skb, queue_index);
334}
335
336/* register_prot_hook must be invoked with the po->bind_lock held,
337 * or from a context in which asynchronous accesses to the packet
338 * socket is not possible (packet_create()).
339 */
340static void register_prot_hook(struct sock *sk)
341{
342 struct packet_sock *po = pkt_sk(sk);
343
344 if (!po->running) {
345 if (po->fanout)
346 __fanout_link(sk, po);
347 else
348 dev_add_pack(&po->prot_hook);
349
350 sock_hold(sk);
351 po->running = 1;
352 }
353}
354
355/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
356 * held. If the sync parameter is true, we will temporarily drop
357 * the po->bind_lock and do a synchronize_net to make sure no
358 * asynchronous packet processing paths still refer to the elements
359 * of po->prot_hook. If the sync parameter is false, it is the
360 * callers responsibility to take care of this.
361 */
362static void __unregister_prot_hook(struct sock *sk, bool sync)
363{
364 struct packet_sock *po = pkt_sk(sk);
365
366 po->running = 0;
367
368 if (po->fanout)
369 __fanout_unlink(sk, po);
370 else
371 __dev_remove_pack(&po->prot_hook);
372
373 __sock_put(sk);
374
375 if (sync) {
376 spin_unlock(&po->bind_lock);
377 synchronize_net();
378 spin_lock(&po->bind_lock);
379 }
380}
381
382static void unregister_prot_hook(struct sock *sk, bool sync)
383{
384 struct packet_sock *po = pkt_sk(sk);
385
386 if (po->running)
387 __unregister_prot_hook(sk, sync);
388}
389
390static inline struct page * __pure pgv_to_page(void *addr)
391{
392 if (is_vmalloc_addr(addr))
393 return vmalloc_to_page(addr);
394 return virt_to_page(addr);
395}
396
397static void __packet_set_status(struct packet_sock *po, void *frame, int status)
398{
399 union tpacket_uhdr h;
400
401 h.raw = frame;
402 switch (po->tp_version) {
403 case TPACKET_V1:
404 h.h1->tp_status = status;
405 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
406 break;
407 case TPACKET_V2:
408 h.h2->tp_status = status;
409 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
410 break;
411 case TPACKET_V3:
412 default:
413 WARN(1, "TPACKET version not supported.\n");
414 BUG();
415 }
416
417 smp_wmb();
418}
419
420static int __packet_get_status(struct packet_sock *po, void *frame)
421{
422 union tpacket_uhdr h;
423
424 smp_rmb();
425
426 h.raw = frame;
427 switch (po->tp_version) {
428 case TPACKET_V1:
429 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
430 return h.h1->tp_status;
431 case TPACKET_V2:
432 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
433 return h.h2->tp_status;
434 case TPACKET_V3:
435 default:
436 WARN(1, "TPACKET version not supported.\n");
437 BUG();
438 return 0;
439 }
440}
441
442static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
443 unsigned int flags)
444{
445 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
446
447 if (shhwtstamps &&
448 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
449 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
450 return TP_STATUS_TS_RAW_HARDWARE;
451
452 if (ktime_to_timespec_cond(skb->tstamp, ts))
453 return TP_STATUS_TS_SOFTWARE;
454
455 return 0;
456}
457
458static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
459 struct sk_buff *skb)
460{
461 union tpacket_uhdr h;
462 struct timespec ts;
463 __u32 ts_status;
464
465 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
466 return 0;
467
468 h.raw = frame;
469 switch (po->tp_version) {
470 case TPACKET_V1:
471 h.h1->tp_sec = ts.tv_sec;
472 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
473 break;
474 case TPACKET_V2:
475 h.h2->tp_sec = ts.tv_sec;
476 h.h2->tp_nsec = ts.tv_nsec;
477 break;
478 case TPACKET_V3:
479 default:
480 WARN(1, "TPACKET version not supported.\n");
481 BUG();
482 }
483
484 /* one flush is safe, as both fields always lie on the same cacheline */
485 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
486 smp_wmb();
487
488 return ts_status;
489}
490
491static void *packet_lookup_frame(struct packet_sock *po,
492 struct packet_ring_buffer *rb,
493 unsigned int position,
494 int status)
495{
496 unsigned int pg_vec_pos, frame_offset;
497 union tpacket_uhdr h;
498
499 pg_vec_pos = position / rb->frames_per_block;
500 frame_offset = position % rb->frames_per_block;
501
502 h.raw = rb->pg_vec[pg_vec_pos].buffer +
503 (frame_offset * rb->frame_size);
504
505 if (status != __packet_get_status(po, h.raw))
506 return NULL;
507
508 return h.raw;
509}
510
511static void *packet_current_frame(struct packet_sock *po,
512 struct packet_ring_buffer *rb,
513 int status)
514{
515 return packet_lookup_frame(po, rb, rb->head, status);
516}
517
518static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
519{
520 del_timer_sync(&pkc->retire_blk_timer);
521}
522
523static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
524 struct sk_buff_head *rb_queue)
525{
526 struct tpacket_kbdq_core *pkc;
527
528 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
529
530 spin_lock_bh(&rb_queue->lock);
531 pkc->delete_blk_timer = 1;
532 spin_unlock_bh(&rb_queue->lock);
533
534 prb_del_retire_blk_timer(pkc);
535}
536
537static void prb_init_blk_timer(struct packet_sock *po,
538 struct tpacket_kbdq_core *pkc,
539 void (*func) (unsigned long))
540{
541 init_timer(&pkc->retire_blk_timer);
542 pkc->retire_blk_timer.data = (long)po;
543 pkc->retire_blk_timer.function = func;
544 pkc->retire_blk_timer.expires = jiffies;
545}
546
547static void prb_setup_retire_blk_timer(struct packet_sock *po)
548{
549 struct tpacket_kbdq_core *pkc;
550
551 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
552 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
553}
554
555static int prb_calc_retire_blk_tmo(struct packet_sock *po,
556 int blk_size_in_bytes)
557{
558 struct net_device *dev;
559 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
560 struct ethtool_link_ksettings ecmd;
561 int err;
562
563 rtnl_lock();
564 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
565 if (unlikely(!dev)) {
566 rtnl_unlock();
567 return DEFAULT_PRB_RETIRE_TOV;
568 }
569 err = __ethtool_get_link_ksettings(dev, &ecmd);
570 rtnl_unlock();
571 if (!err) {
572 /*
573 * If the link speed is so slow you don't really
574 * need to worry about perf anyways
575 */
576 if (ecmd.base.speed < SPEED_1000 ||
577 ecmd.base.speed == SPEED_UNKNOWN) {
578 return DEFAULT_PRB_RETIRE_TOV;
579 } else {
580 msec = 1;
581 div = ecmd.base.speed / 1000;
582 }
583 }
584
585 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
586
587 if (div)
588 mbits /= div;
589
590 tmo = mbits * msec;
591
592 if (div)
593 return tmo+1;
594 return tmo;
595}
596
597static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
598 union tpacket_req_u *req_u)
599{
600 p1->feature_req_word = req_u->req3.tp_feature_req_word;
601}
602
603static void init_prb_bdqc(struct packet_sock *po,
604 struct packet_ring_buffer *rb,
605 struct pgv *pg_vec,
606 union tpacket_req_u *req_u)
607{
608 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
609 struct tpacket_block_desc *pbd;
610
611 memset(p1, 0x0, sizeof(*p1));
612
613 p1->knxt_seq_num = 1;
614 p1->pkbdq = pg_vec;
615 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
616 p1->pkblk_start = pg_vec[0].buffer;
617 p1->kblk_size = req_u->req3.tp_block_size;
618 p1->knum_blocks = req_u->req3.tp_block_nr;
619 p1->hdrlen = po->tp_hdrlen;
620 p1->version = po->tp_version;
621 p1->last_kactive_blk_num = 0;
622 po->stats.stats3.tp_freeze_q_cnt = 0;
623 if (req_u->req3.tp_retire_blk_tov)
624 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
625 else
626 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
627 req_u->req3.tp_block_size);
628 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
629 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
630
631 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
632 prb_init_ft_ops(p1, req_u);
633 prb_setup_retire_blk_timer(po);
634 prb_open_block(p1, pbd);
635}
636
637/* Do NOT update the last_blk_num first.
638 * Assumes sk_buff_head lock is held.
639 */
640static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
641{
642 mod_timer(&pkc->retire_blk_timer,
643 jiffies + pkc->tov_in_jiffies);
644 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
645}
646
647/*
648 * Timer logic:
649 * 1) We refresh the timer only when we open a block.
650 * By doing this we don't waste cycles refreshing the timer
651 * on packet-by-packet basis.
652 *
653 * With a 1MB block-size, on a 1Gbps line, it will take
654 * i) ~8 ms to fill a block + ii) memcpy etc.
655 * In this cut we are not accounting for the memcpy time.
656 *
657 * So, if the user sets the 'tmo' to 10ms then the timer
658 * will never fire while the block is still getting filled
659 * (which is what we want). However, the user could choose
660 * to close a block early and that's fine.
661 *
662 * But when the timer does fire, we check whether or not to refresh it.
663 * Since the tmo granularity is in msecs, it is not too expensive
664 * to refresh the timer, lets say every '8' msecs.
665 * Either the user can set the 'tmo' or we can derive it based on
666 * a) line-speed and b) block-size.
667 * prb_calc_retire_blk_tmo() calculates the tmo.
668 *
669 */
670static void prb_retire_rx_blk_timer_expired(unsigned long data)
671{
672 struct packet_sock *po = (struct packet_sock *)data;
673 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
674 unsigned int frozen;
675 struct tpacket_block_desc *pbd;
676
677 spin_lock(&po->sk.sk_receive_queue.lock);
678
679 frozen = prb_queue_frozen(pkc);
680 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
681
682 if (unlikely(pkc->delete_blk_timer))
683 goto out;
684
685 /* We only need to plug the race when the block is partially filled.
686 * tpacket_rcv:
687 * lock(); increment BLOCK_NUM_PKTS; unlock()
688 * copy_bits() is in progress ...
689 * timer fires on other cpu:
690 * we can't retire the current block because copy_bits
691 * is in progress.
692 *
693 */
694 if (BLOCK_NUM_PKTS(pbd)) {
695 while (atomic_read(&pkc->blk_fill_in_prog)) {
696 /* Waiting for skb_copy_bits to finish... */
697 cpu_relax();
698 }
699 }
700
701 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
702 if (!frozen) {
703 if (!BLOCK_NUM_PKTS(pbd)) {
704 /* An empty block. Just refresh the timer. */
705 goto refresh_timer;
706 }
707 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
708 if (!prb_dispatch_next_block(pkc, po))
709 goto refresh_timer;
710 else
711 goto out;
712 } else {
713 /* Case 1. Queue was frozen because user-space was
714 * lagging behind.
715 */
716 if (prb_curr_blk_in_use(pkc, pbd)) {
717 /*
718 * Ok, user-space is still behind.
719 * So just refresh the timer.
720 */
721 goto refresh_timer;
722 } else {
723 /* Case 2. queue was frozen,user-space caught up,
724 * now the link went idle && the timer fired.
725 * We don't have a block to close.So we open this
726 * block and restart the timer.
727 * opening a block thaws the queue,restarts timer
728 * Thawing/timer-refresh is a side effect.
729 */
730 prb_open_block(pkc, pbd);
731 goto out;
732 }
733 }
734 }
735
736refresh_timer:
737 _prb_refresh_rx_retire_blk_timer(pkc);
738
739out:
740 spin_unlock(&po->sk.sk_receive_queue.lock);
741}
742
743static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
744 struct tpacket_block_desc *pbd1, __u32 status)
745{
746 /* Flush everything minus the block header */
747
748#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
749 u8 *start, *end;
750
751 start = (u8 *)pbd1;
752
753 /* Skip the block header(we know header WILL fit in 4K) */
754 start += PAGE_SIZE;
755
756 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
757 for (; start < end; start += PAGE_SIZE)
758 flush_dcache_page(pgv_to_page(start));
759
760 smp_wmb();
761#endif
762
763 /* Now update the block status. */
764
765 BLOCK_STATUS(pbd1) = status;
766
767 /* Flush the block header */
768
769#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
770 start = (u8 *)pbd1;
771 flush_dcache_page(pgv_to_page(start));
772
773 smp_wmb();
774#endif
775}
776
777/*
778 * Side effect:
779 *
780 * 1) flush the block
781 * 2) Increment active_blk_num
782 *
783 * Note:We DONT refresh the timer on purpose.
784 * Because almost always the next block will be opened.
785 */
786static void prb_close_block(struct tpacket_kbdq_core *pkc1,
787 struct tpacket_block_desc *pbd1,
788 struct packet_sock *po, unsigned int stat)
789{
790 __u32 status = TP_STATUS_USER | stat;
791
792 struct tpacket3_hdr *last_pkt;
793 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
794 struct sock *sk = &po->sk;
795
796 if (po->stats.stats3.tp_drops)
797 status |= TP_STATUS_LOSING;
798
799 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
800 last_pkt->tp_next_offset = 0;
801
802 /* Get the ts of the last pkt */
803 if (BLOCK_NUM_PKTS(pbd1)) {
804 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
805 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
806 } else {
807 /* Ok, we tmo'd - so get the current time.
808 *
809 * It shouldn't really happen as we don't close empty
810 * blocks. See prb_retire_rx_blk_timer_expired().
811 */
812 struct timespec ts;
813 getnstimeofday(&ts);
814 h1->ts_last_pkt.ts_sec = ts.tv_sec;
815 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
816 }
817
818 smp_wmb();
819
820 /* Flush the block */
821 prb_flush_block(pkc1, pbd1, status);
822
823 sk->sk_data_ready(sk);
824
825 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
826}
827
828static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
829{
830 pkc->reset_pending_on_curr_blk = 0;
831}
832
833/*
834 * Side effect of opening a block:
835 *
836 * 1) prb_queue is thawed.
837 * 2) retire_blk_timer is refreshed.
838 *
839 */
840static void prb_open_block(struct tpacket_kbdq_core *pkc1,
841 struct tpacket_block_desc *pbd1)
842{
843 struct timespec ts;
844 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
845
846 smp_rmb();
847
848 /* We could have just memset this but we will lose the
849 * flexibility of making the priv area sticky
850 */
851
852 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
853 BLOCK_NUM_PKTS(pbd1) = 0;
854 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
855
856 getnstimeofday(&ts);
857
858 h1->ts_first_pkt.ts_sec = ts.tv_sec;
859 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
860
861 pkc1->pkblk_start = (char *)pbd1;
862 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
863
864 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
865 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
866
867 pbd1->version = pkc1->version;
868 pkc1->prev = pkc1->nxt_offset;
869 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
870
871 prb_thaw_queue(pkc1);
872 _prb_refresh_rx_retire_blk_timer(pkc1);
873
874 smp_wmb();
875}
876
877/*
878 * Queue freeze logic:
879 * 1) Assume tp_block_nr = 8 blocks.
880 * 2) At time 't0', user opens Rx ring.
881 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
882 * 4) user-space is either sleeping or processing block '0'.
883 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
884 * it will close block-7,loop around and try to fill block '0'.
885 * call-flow:
886 * __packet_lookup_frame_in_block
887 * prb_retire_current_block()
888 * prb_dispatch_next_block()
889 * |->(BLOCK_STATUS == USER) evaluates to true
890 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
891 * 6) Now there are two cases:
892 * 6.1) Link goes idle right after the queue is frozen.
893 * But remember, the last open_block() refreshed the timer.
894 * When this timer expires,it will refresh itself so that we can
895 * re-open block-0 in near future.
896 * 6.2) Link is busy and keeps on receiving packets. This is a simple
897 * case and __packet_lookup_frame_in_block will check if block-0
898 * is free and can now be re-used.
899 */
900static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
901 struct packet_sock *po)
902{
903 pkc->reset_pending_on_curr_blk = 1;
904 po->stats.stats3.tp_freeze_q_cnt++;
905}
906
907#define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
908
909/*
910 * If the next block is free then we will dispatch it
911 * and return a good offset.
912 * Else, we will freeze the queue.
913 * So, caller must check the return value.
914 */
915static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
916 struct packet_sock *po)
917{
918 struct tpacket_block_desc *pbd;
919
920 smp_rmb();
921
922 /* 1. Get current block num */
923 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
924
925 /* 2. If this block is currently in_use then freeze the queue */
926 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
927 prb_freeze_queue(pkc, po);
928 return NULL;
929 }
930
931 /*
932 * 3.
933 * open this block and return the offset where the first packet
934 * needs to get stored.
935 */
936 prb_open_block(pkc, pbd);
937 return (void *)pkc->nxt_offset;
938}
939
940static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
941 struct packet_sock *po, unsigned int status)
942{
943 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
944
945 /* retire/close the current block */
946 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
947 /*
948 * Plug the case where copy_bits() is in progress on
949 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
950 * have space to copy the pkt in the current block and
951 * called prb_retire_current_block()
952 *
953 * We don't need to worry about the TMO case because
954 * the timer-handler already handled this case.
955 */
956 if (!(status & TP_STATUS_BLK_TMO)) {
957 while (atomic_read(&pkc->blk_fill_in_prog)) {
958 /* Waiting for skb_copy_bits to finish... */
959 cpu_relax();
960 }
961 }
962 prb_close_block(pkc, pbd, po, status);
963 return;
964 }
965}
966
967static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
968 struct tpacket_block_desc *pbd)
969{
970 return TP_STATUS_USER & BLOCK_STATUS(pbd);
971}
972
973static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
974{
975 return pkc->reset_pending_on_curr_blk;
976}
977
978static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
979{
980 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
981 atomic_dec(&pkc->blk_fill_in_prog);
982}
983
984static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
985 struct tpacket3_hdr *ppd)
986{
987 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
988}
989
990static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
991 struct tpacket3_hdr *ppd)
992{
993 ppd->hv1.tp_rxhash = 0;
994}
995
996static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
997 struct tpacket3_hdr *ppd)
998{
999 if (skb_vlan_tag_present(pkc->skb)) {
1000 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1001 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1002 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1003 } else {
1004 ppd->hv1.tp_vlan_tci = 0;
1005 ppd->hv1.tp_vlan_tpid = 0;
1006 ppd->tp_status = TP_STATUS_AVAILABLE;
1007 }
1008}
1009
1010static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1011 struct tpacket3_hdr *ppd)
1012{
1013 ppd->hv1.tp_padding = 0;
1014 prb_fill_vlan_info(pkc, ppd);
1015
1016 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1017 prb_fill_rxhash(pkc, ppd);
1018 else
1019 prb_clear_rxhash(pkc, ppd);
1020}
1021
1022static void prb_fill_curr_block(char *curr,
1023 struct tpacket_kbdq_core *pkc,
1024 struct tpacket_block_desc *pbd,
1025 unsigned int len)
1026{
1027 struct tpacket3_hdr *ppd;
1028
1029 ppd = (struct tpacket3_hdr *)curr;
1030 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1031 pkc->prev = curr;
1032 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1033 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1034 BLOCK_NUM_PKTS(pbd) += 1;
1035 atomic_inc(&pkc->blk_fill_in_prog);
1036 prb_run_all_ft_ops(pkc, ppd);
1037}
1038
1039/* Assumes caller has the sk->rx_queue.lock */
1040static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1041 struct sk_buff *skb,
1042 int status,
1043 unsigned int len
1044 )
1045{
1046 struct tpacket_kbdq_core *pkc;
1047 struct tpacket_block_desc *pbd;
1048 char *curr, *end;
1049
1050 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1051 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1052
1053 /* Queue is frozen when user space is lagging behind */
1054 if (prb_queue_frozen(pkc)) {
1055 /*
1056 * Check if that last block which caused the queue to freeze,
1057 * is still in_use by user-space.
1058 */
1059 if (prb_curr_blk_in_use(pkc, pbd)) {
1060 /* Can't record this packet */
1061 return NULL;
1062 } else {
1063 /*
1064 * Ok, the block was released by user-space.
1065 * Now let's open that block.
1066 * opening a block also thaws the queue.
1067 * Thawing is a side effect.
1068 */
1069 prb_open_block(pkc, pbd);
1070 }
1071 }
1072
1073 smp_mb();
1074 curr = pkc->nxt_offset;
1075 pkc->skb = skb;
1076 end = (char *)pbd + pkc->kblk_size;
1077
1078 /* first try the current block */
1079 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1080 prb_fill_curr_block(curr, pkc, pbd, len);
1081 return (void *)curr;
1082 }
1083
1084 /* Ok, close the current block */
1085 prb_retire_current_block(pkc, po, 0);
1086
1087 /* Now, try to dispatch the next block */
1088 curr = (char *)prb_dispatch_next_block(pkc, po);
1089 if (curr) {
1090 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1091 prb_fill_curr_block(curr, pkc, pbd, len);
1092 return (void *)curr;
1093 }
1094
1095 /*
1096 * No free blocks are available.user_space hasn't caught up yet.
1097 * Queue was just frozen and now this packet will get dropped.
1098 */
1099 return NULL;
1100}
1101
1102static void *packet_current_rx_frame(struct packet_sock *po,
1103 struct sk_buff *skb,
1104 int status, unsigned int len)
1105{
1106 char *curr = NULL;
1107 switch (po->tp_version) {
1108 case TPACKET_V1:
1109 case TPACKET_V2:
1110 curr = packet_lookup_frame(po, &po->rx_ring,
1111 po->rx_ring.head, status);
1112 return curr;
1113 case TPACKET_V3:
1114 return __packet_lookup_frame_in_block(po, skb, status, len);
1115 default:
1116 WARN(1, "TPACKET version not supported\n");
1117 BUG();
1118 return NULL;
1119 }
1120}
1121
1122static void *prb_lookup_block(struct packet_sock *po,
1123 struct packet_ring_buffer *rb,
1124 unsigned int idx,
1125 int status)
1126{
1127 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1128 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1129
1130 if (status != BLOCK_STATUS(pbd))
1131 return NULL;
1132 return pbd;
1133}
1134
1135static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1136{
1137 unsigned int prev;
1138 if (rb->prb_bdqc.kactive_blk_num)
1139 prev = rb->prb_bdqc.kactive_blk_num-1;
1140 else
1141 prev = rb->prb_bdqc.knum_blocks-1;
1142 return prev;
1143}
1144
1145/* Assumes caller has held the rx_queue.lock */
1146static void *__prb_previous_block(struct packet_sock *po,
1147 struct packet_ring_buffer *rb,
1148 int status)
1149{
1150 unsigned int previous = prb_previous_blk_num(rb);
1151 return prb_lookup_block(po, rb, previous, status);
1152}
1153
1154static void *packet_previous_rx_frame(struct packet_sock *po,
1155 struct packet_ring_buffer *rb,
1156 int status)
1157{
1158 if (po->tp_version <= TPACKET_V2)
1159 return packet_previous_frame(po, rb, status);
1160
1161 return __prb_previous_block(po, rb, status);
1162}
1163
1164static void packet_increment_rx_head(struct packet_sock *po,
1165 struct packet_ring_buffer *rb)
1166{
1167 switch (po->tp_version) {
1168 case TPACKET_V1:
1169 case TPACKET_V2:
1170 return packet_increment_head(rb);
1171 case TPACKET_V3:
1172 default:
1173 WARN(1, "TPACKET version not supported.\n");
1174 BUG();
1175 return;
1176 }
1177}
1178
1179static void *packet_previous_frame(struct packet_sock *po,
1180 struct packet_ring_buffer *rb,
1181 int status)
1182{
1183 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1184 return packet_lookup_frame(po, rb, previous, status);
1185}
1186
1187static void packet_increment_head(struct packet_ring_buffer *buff)
1188{
1189 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1190}
1191
1192static void packet_inc_pending(struct packet_ring_buffer *rb)
1193{
1194 this_cpu_inc(*rb->pending_refcnt);
1195}
1196
1197static void packet_dec_pending(struct packet_ring_buffer *rb)
1198{
1199 this_cpu_dec(*rb->pending_refcnt);
1200}
1201
1202static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1203{
1204 unsigned int refcnt = 0;
1205 int cpu;
1206
1207 /* We don't use pending refcount in rx_ring. */
1208 if (rb->pending_refcnt == NULL)
1209 return 0;
1210
1211 for_each_possible_cpu(cpu)
1212 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1213
1214 return refcnt;
1215}
1216
1217static int packet_alloc_pending(struct packet_sock *po)
1218{
1219 po->rx_ring.pending_refcnt = NULL;
1220
1221 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1222 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1223 return -ENOBUFS;
1224
1225 return 0;
1226}
1227
1228static void packet_free_pending(struct packet_sock *po)
1229{
1230 free_percpu(po->tx_ring.pending_refcnt);
1231}
1232
1233#define ROOM_POW_OFF 2
1234#define ROOM_NONE 0x0
1235#define ROOM_LOW 0x1
1236#define ROOM_NORMAL 0x2
1237
1238static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1239{
1240 int idx, len;
1241
1242 len = po->rx_ring.frame_max + 1;
1243 idx = po->rx_ring.head;
1244 if (pow_off)
1245 idx += len >> pow_off;
1246 if (idx >= len)
1247 idx -= len;
1248 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1249}
1250
1251static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1252{
1253 int idx, len;
1254
1255 len = po->rx_ring.prb_bdqc.knum_blocks;
1256 idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1257 if (pow_off)
1258 idx += len >> pow_off;
1259 if (idx >= len)
1260 idx -= len;
1261 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1262}
1263
1264static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1265{
1266 struct sock *sk = &po->sk;
1267 int ret = ROOM_NONE;
1268
1269 if (po->prot_hook.func != tpacket_rcv) {
1270 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1271 - (skb ? skb->truesize : 0);
1272 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1273 return ROOM_NORMAL;
1274 else if (avail > 0)
1275 return ROOM_LOW;
1276 else
1277 return ROOM_NONE;
1278 }
1279
1280 if (po->tp_version == TPACKET_V3) {
1281 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1282 ret = ROOM_NORMAL;
1283 else if (__tpacket_v3_has_room(po, 0))
1284 ret = ROOM_LOW;
1285 } else {
1286 if (__tpacket_has_room(po, ROOM_POW_OFF))
1287 ret = ROOM_NORMAL;
1288 else if (__tpacket_has_room(po, 0))
1289 ret = ROOM_LOW;
1290 }
1291
1292 return ret;
1293}
1294
1295static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1296{
1297 int ret;
1298 bool has_room;
1299
1300 spin_lock_bh(&po->sk.sk_receive_queue.lock);
1301 ret = __packet_rcv_has_room(po, skb);
1302 has_room = ret == ROOM_NORMAL;
1303 if (po->pressure == has_room)
1304 po->pressure = !has_room;
1305 spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1306
1307 return ret;
1308}
1309
1310static void packet_sock_destruct(struct sock *sk)
1311{
1312 skb_queue_purge(&sk->sk_error_queue);
1313
1314 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1315 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1316
1317 if (!sock_flag(sk, SOCK_DEAD)) {
1318 pr_err("Attempt to release alive packet socket: %p\n", sk);
1319 return;
1320 }
1321
1322 sk_refcnt_debug_dec(sk);
1323}
1324
1325static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1326{
1327 u32 rxhash;
1328 int i, count = 0;
1329
1330 rxhash = skb_get_hash(skb);
1331 for (i = 0; i < ROLLOVER_HLEN; i++)
1332 if (po->rollover->history[i] == rxhash)
1333 count++;
1334
1335 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
1336 return count > (ROLLOVER_HLEN >> 1);
1337}
1338
1339static unsigned int fanout_demux_hash(struct packet_fanout *f,
1340 struct sk_buff *skb,
1341 unsigned int num)
1342{
1343 return reciprocal_scale(skb_get_hash(skb), num);
1344}
1345
1346static unsigned int fanout_demux_lb(struct packet_fanout *f,
1347 struct sk_buff *skb,
1348 unsigned int num)
1349{
1350 unsigned int val = atomic_inc_return(&f->rr_cur);
1351
1352 return val % num;
1353}
1354
1355static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1356 struct sk_buff *skb,
1357 unsigned int num)
1358{
1359 return smp_processor_id() % num;
1360}
1361
1362static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1363 struct sk_buff *skb,
1364 unsigned int num)
1365{
1366 return prandom_u32_max(num);
1367}
1368
1369static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1370 struct sk_buff *skb,
1371 unsigned int idx, bool try_self,
1372 unsigned int num)
1373{
1374 struct packet_sock *po, *po_next, *po_skip = NULL;
1375 unsigned int i, j, room = ROOM_NONE;
1376
1377 po = pkt_sk(f->arr[idx]);
1378
1379 if (try_self) {
1380 room = packet_rcv_has_room(po, skb);
1381 if (room == ROOM_NORMAL ||
1382 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1383 return idx;
1384 po_skip = po;
1385 }
1386
1387 i = j = min_t(int, po->rollover->sock, num - 1);
1388 do {
1389 po_next = pkt_sk(f->arr[i]);
1390 if (po_next != po_skip && !po_next->pressure &&
1391 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1392 if (i != j)
1393 po->rollover->sock = i;
1394 atomic_long_inc(&po->rollover->num);
1395 if (room == ROOM_LOW)
1396 atomic_long_inc(&po->rollover->num_huge);
1397 return i;
1398 }
1399
1400 if (++i == num)
1401 i = 0;
1402 } while (i != j);
1403
1404 atomic_long_inc(&po->rollover->num_failed);
1405 return idx;
1406}
1407
1408static unsigned int fanout_demux_qm(struct packet_fanout *f,
1409 struct sk_buff *skb,
1410 unsigned int num)
1411{
1412 return skb_get_queue_mapping(skb) % num;
1413}
1414
1415static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1416 struct sk_buff *skb,
1417 unsigned int num)
1418{
1419 struct bpf_prog *prog;
1420 unsigned int ret = 0;
1421
1422 rcu_read_lock();
1423 prog = rcu_dereference(f->bpf_prog);
1424 if (prog)
1425 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1426 rcu_read_unlock();
1427
1428 return ret;
1429}
1430
1431static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1432{
1433 return f->flags & (flag >> 8);
1434}
1435
1436static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1437 struct packet_type *pt, struct net_device *orig_dev)
1438{
1439 struct packet_fanout *f = pt->af_packet_priv;
1440 unsigned int num = READ_ONCE(f->num_members);
1441 struct net *net = read_pnet(&f->net);
1442 struct packet_sock *po;
1443 unsigned int idx;
1444
1445 if (!net_eq(dev_net(dev), net) || !num) {
1446 kfree_skb(skb);
1447 return 0;
1448 }
1449
1450 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1451 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1452 if (!skb)
1453 return 0;
1454 }
1455 switch (f->type) {
1456 case PACKET_FANOUT_HASH:
1457 default:
1458 idx = fanout_demux_hash(f, skb, num);
1459 break;
1460 case PACKET_FANOUT_LB:
1461 idx = fanout_demux_lb(f, skb, num);
1462 break;
1463 case PACKET_FANOUT_CPU:
1464 idx = fanout_demux_cpu(f, skb, num);
1465 break;
1466 case PACKET_FANOUT_RND:
1467 idx = fanout_demux_rnd(f, skb, num);
1468 break;
1469 case PACKET_FANOUT_QM:
1470 idx = fanout_demux_qm(f, skb, num);
1471 break;
1472 case PACKET_FANOUT_ROLLOVER:
1473 idx = fanout_demux_rollover(f, skb, 0, false, num);
1474 break;
1475 case PACKET_FANOUT_CBPF:
1476 case PACKET_FANOUT_EBPF:
1477 idx = fanout_demux_bpf(f, skb, num);
1478 break;
1479 }
1480
1481 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1482 idx = fanout_demux_rollover(f, skb, idx, true, num);
1483
1484 po = pkt_sk(f->arr[idx]);
1485 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1486}
1487
1488DEFINE_MUTEX(fanout_mutex);
1489EXPORT_SYMBOL_GPL(fanout_mutex);
1490static LIST_HEAD(fanout_list);
1491
1492static void __fanout_link(struct sock *sk, struct packet_sock *po)
1493{
1494 struct packet_fanout *f = po->fanout;
1495
1496 spin_lock(&f->lock);
1497 f->arr[f->num_members] = sk;
1498 smp_wmb();
1499 f->num_members++;
1500 spin_unlock(&f->lock);
1501}
1502
1503static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1504{
1505 struct packet_fanout *f = po->fanout;
1506 int i;
1507
1508 spin_lock(&f->lock);
1509 for (i = 0; i < f->num_members; i++) {
1510 if (f->arr[i] == sk)
1511 break;
1512 }
1513 BUG_ON(i >= f->num_members);
1514 f->arr[i] = f->arr[f->num_members - 1];
1515 f->num_members--;
1516 spin_unlock(&f->lock);
1517}
1518
1519static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1520{
1521 if (sk->sk_family != PF_PACKET)
1522 return false;
1523
1524 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1525}
1526
1527static void fanout_init_data(struct packet_fanout *f)
1528{
1529 switch (f->type) {
1530 case PACKET_FANOUT_LB:
1531 atomic_set(&f->rr_cur, 0);
1532 break;
1533 case PACKET_FANOUT_CBPF:
1534 case PACKET_FANOUT_EBPF:
1535 RCU_INIT_POINTER(f->bpf_prog, NULL);
1536 break;
1537 }
1538}
1539
1540static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1541{
1542 struct bpf_prog *old;
1543
1544 spin_lock(&f->lock);
1545 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1546 rcu_assign_pointer(f->bpf_prog, new);
1547 spin_unlock(&f->lock);
1548
1549 if (old) {
1550 synchronize_net();
1551 bpf_prog_destroy(old);
1552 }
1553}
1554
1555static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
1556 unsigned int len)
1557{
1558 struct bpf_prog *new;
1559 struct sock_fprog fprog;
1560 int ret;
1561
1562 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1563 return -EPERM;
1564 if (len != sizeof(fprog))
1565 return -EINVAL;
1566 if (copy_from_user(&fprog, data, len))
1567 return -EFAULT;
1568
1569 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1570 if (ret)
1571 return ret;
1572
1573 __fanout_set_data_bpf(po->fanout, new);
1574 return 0;
1575}
1576
1577static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
1578 unsigned int len)
1579{
1580 struct bpf_prog *new;
1581 u32 fd;
1582
1583 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1584 return -EPERM;
1585 if (len != sizeof(fd))
1586 return -EINVAL;
1587 if (copy_from_user(&fd, data, len))
1588 return -EFAULT;
1589
1590 new = bpf_prog_get(fd);
1591 if (IS_ERR(new))
1592 return PTR_ERR(new);
1593 if (new->type != BPF_PROG_TYPE_SOCKET_FILTER) {
1594 bpf_prog_put(new);
1595 return -EINVAL;
1596 }
1597
1598 __fanout_set_data_bpf(po->fanout, new);
1599 return 0;
1600}
1601
1602static int fanout_set_data(struct packet_sock *po, char __user *data,
1603 unsigned int len)
1604{
1605 switch (po->fanout->type) {
1606 case PACKET_FANOUT_CBPF:
1607 return fanout_set_data_cbpf(po, data, len);
1608 case PACKET_FANOUT_EBPF:
1609 return fanout_set_data_ebpf(po, data, len);
1610 default:
1611 return -EINVAL;
1612 };
1613}
1614
1615static void fanout_release_data(struct packet_fanout *f)
1616{
1617 switch (f->type) {
1618 case PACKET_FANOUT_CBPF:
1619 case PACKET_FANOUT_EBPF:
1620 __fanout_set_data_bpf(f, NULL);
1621 };
1622}
1623
1624static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1625{
1626 struct packet_sock *po = pkt_sk(sk);
1627 struct packet_fanout *f, *match;
1628 u8 type = type_flags & 0xff;
1629 u8 flags = type_flags >> 8;
1630 int err;
1631
1632 switch (type) {
1633 case PACKET_FANOUT_ROLLOVER:
1634 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1635 return -EINVAL;
1636 case PACKET_FANOUT_HASH:
1637 case PACKET_FANOUT_LB:
1638 case PACKET_FANOUT_CPU:
1639 case PACKET_FANOUT_RND:
1640 case PACKET_FANOUT_QM:
1641 case PACKET_FANOUT_CBPF:
1642 case PACKET_FANOUT_EBPF:
1643 break;
1644 default:
1645 return -EINVAL;
1646 }
1647
1648 if (!po->running)
1649 return -EINVAL;
1650
1651 if (po->fanout)
1652 return -EALREADY;
1653
1654 if (type == PACKET_FANOUT_ROLLOVER ||
1655 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1656 po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
1657 if (!po->rollover)
1658 return -ENOMEM;
1659 atomic_long_set(&po->rollover->num, 0);
1660 atomic_long_set(&po->rollover->num_huge, 0);
1661 atomic_long_set(&po->rollover->num_failed, 0);
1662 }
1663
1664 mutex_lock(&fanout_mutex);
1665 match = NULL;
1666 list_for_each_entry(f, &fanout_list, list) {
1667 if (f->id == id &&
1668 read_pnet(&f->net) == sock_net(sk)) {
1669 match = f;
1670 break;
1671 }
1672 }
1673 err = -EINVAL;
1674 if (match && match->flags != flags)
1675 goto out;
1676 if (!match) {
1677 err = -ENOMEM;
1678 match = kzalloc(sizeof(*match), GFP_KERNEL);
1679 if (!match)
1680 goto out;
1681 write_pnet(&match->net, sock_net(sk));
1682 match->id = id;
1683 match->type = type;
1684 match->flags = flags;
1685 INIT_LIST_HEAD(&match->list);
1686 spin_lock_init(&match->lock);
1687 atomic_set(&match->sk_ref, 0);
1688 fanout_init_data(match);
1689 match->prot_hook.type = po->prot_hook.type;
1690 match->prot_hook.dev = po->prot_hook.dev;
1691 match->prot_hook.func = packet_rcv_fanout;
1692 match->prot_hook.af_packet_priv = match;
1693 match->prot_hook.id_match = match_fanout_group;
1694 dev_add_pack(&match->prot_hook);
1695 list_add(&match->list, &fanout_list);
1696 }
1697 err = -EINVAL;
1698 if (match->type == type &&
1699 match->prot_hook.type == po->prot_hook.type &&
1700 match->prot_hook.dev == po->prot_hook.dev) {
1701 err = -ENOSPC;
1702 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1703 __dev_remove_pack(&po->prot_hook);
1704 po->fanout = match;
1705 atomic_inc(&match->sk_ref);
1706 __fanout_link(sk, po);
1707 err = 0;
1708 }
1709 }
1710out:
1711 mutex_unlock(&fanout_mutex);
1712 if (err) {
1713 kfree(po->rollover);
1714 po->rollover = NULL;
1715 }
1716 return err;
1717}
1718
1719static void fanout_release(struct sock *sk)
1720{
1721 struct packet_sock *po = pkt_sk(sk);
1722 struct packet_fanout *f;
1723
1724 f = po->fanout;
1725 if (!f)
1726 return;
1727
1728 mutex_lock(&fanout_mutex);
1729 po->fanout = NULL;
1730
1731 if (atomic_dec_and_test(&f->sk_ref)) {
1732 list_del(&f->list);
1733 dev_remove_pack(&f->prot_hook);
1734 fanout_release_data(f);
1735 kfree(f);
1736 }
1737 mutex_unlock(&fanout_mutex);
1738
1739 if (po->rollover)
1740 kfree_rcu(po->rollover, rcu);
1741}
1742
1743static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1744 struct sk_buff *skb)
1745{
1746 /* Earlier code assumed this would be a VLAN pkt, double-check
1747 * this now that we have the actual packet in hand. We can only
1748 * do this check on Ethernet devices.
1749 */
1750 if (unlikely(dev->type != ARPHRD_ETHER))
1751 return false;
1752
1753 skb_reset_mac_header(skb);
1754 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1755}
1756
1757static const struct proto_ops packet_ops;
1758
1759static const struct proto_ops packet_ops_spkt;
1760
1761static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1762 struct packet_type *pt, struct net_device *orig_dev)
1763{
1764 struct sock *sk;
1765 struct sockaddr_pkt *spkt;
1766
1767 /*
1768 * When we registered the protocol we saved the socket in the data
1769 * field for just this event.
1770 */
1771
1772 sk = pt->af_packet_priv;
1773
1774 /*
1775 * Yank back the headers [hope the device set this
1776 * right or kerboom...]
1777 *
1778 * Incoming packets have ll header pulled,
1779 * push it back.
1780 *
1781 * For outgoing ones skb->data == skb_mac_header(skb)
1782 * so that this procedure is noop.
1783 */
1784
1785 if (skb->pkt_type == PACKET_LOOPBACK)
1786 goto out;
1787
1788 if (!net_eq(dev_net(dev), sock_net(sk)))
1789 goto out;
1790
1791 skb = skb_share_check(skb, GFP_ATOMIC);
1792 if (skb == NULL)
1793 goto oom;
1794
1795 /* drop any routing info */
1796 skb_dst_drop(skb);
1797
1798 /* drop conntrack reference */
1799 nf_reset(skb);
1800
1801 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1802
1803 skb_push(skb, skb->data - skb_mac_header(skb));
1804
1805 /*
1806 * The SOCK_PACKET socket receives _all_ frames.
1807 */
1808
1809 spkt->spkt_family = dev->type;
1810 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1811 spkt->spkt_protocol = skb->protocol;
1812
1813 /*
1814 * Charge the memory to the socket. This is done specifically
1815 * to prevent sockets using all the memory up.
1816 */
1817
1818 if (sock_queue_rcv_skb(sk, skb) == 0)
1819 return 0;
1820
1821out:
1822 kfree_skb(skb);
1823oom:
1824 return 0;
1825}
1826
1827
1828/*
1829 * Output a raw packet to a device layer. This bypasses all the other
1830 * protocol layers and you must therefore supply it with a complete frame
1831 */
1832
1833static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1834 size_t len)
1835{
1836 struct sock *sk = sock->sk;
1837 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1838 struct sk_buff *skb = NULL;
1839 struct net_device *dev;
1840 __be16 proto = 0;
1841 int err;
1842 int extra_len = 0;
1843
1844 /*
1845 * Get and verify the address.
1846 */
1847
1848 if (saddr) {
1849 if (msg->msg_namelen < sizeof(struct sockaddr))
1850 return -EINVAL;
1851 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1852 proto = saddr->spkt_protocol;
1853 } else
1854 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1855
1856 /*
1857 * Find the device first to size check it
1858 */
1859
1860 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1861retry:
1862 rcu_read_lock();
1863 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1864 err = -ENODEV;
1865 if (dev == NULL)
1866 goto out_unlock;
1867
1868 err = -ENETDOWN;
1869 if (!(dev->flags & IFF_UP))
1870 goto out_unlock;
1871
1872 /*
1873 * You may not queue a frame bigger than the mtu. This is the lowest level
1874 * raw protocol and you must do your own fragmentation at this level.
1875 */
1876
1877 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1878 if (!netif_supports_nofcs(dev)) {
1879 err = -EPROTONOSUPPORT;
1880 goto out_unlock;
1881 }
1882 extra_len = 4; /* We're doing our own CRC */
1883 }
1884
1885 err = -EMSGSIZE;
1886 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1887 goto out_unlock;
1888
1889 if (!skb) {
1890 size_t reserved = LL_RESERVED_SPACE(dev);
1891 int tlen = dev->needed_tailroom;
1892 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1893
1894 rcu_read_unlock();
1895 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1896 if (skb == NULL)
1897 return -ENOBUFS;
1898 /* FIXME: Save some space for broken drivers that write a hard
1899 * header at transmission time by themselves. PPP is the notable
1900 * one here. This should really be fixed at the driver level.
1901 */
1902 skb_reserve(skb, reserved);
1903 skb_reset_network_header(skb);
1904
1905 /* Try to align data part correctly */
1906 if (hhlen) {
1907 skb->data -= hhlen;
1908 skb->tail -= hhlen;
1909 if (len < hhlen)
1910 skb_reset_network_header(skb);
1911 }
1912 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1913 if (err)
1914 goto out_free;
1915 goto retry;
1916 }
1917
1918 if (!dev_validate_header(dev, skb->data, len)) {
1919 err = -EINVAL;
1920 goto out_unlock;
1921 }
1922 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
1923 !packet_extra_vlan_len_allowed(dev, skb)) {
1924 err = -EMSGSIZE;
1925 goto out_unlock;
1926 }
1927
1928 skb->protocol = proto;
1929 skb->dev = dev;
1930 skb->priority = sk->sk_priority;
1931 skb->mark = sk->sk_mark;
1932
1933 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1934
1935 if (unlikely(extra_len == 4))
1936 skb->no_fcs = 1;
1937
1938 skb_probe_transport_header(skb, 0);
1939
1940 dev_queue_xmit(skb);
1941 rcu_read_unlock();
1942 return len;
1943
1944out_unlock:
1945 rcu_read_unlock();
1946out_free:
1947 kfree_skb(skb);
1948 return err;
1949}
1950
1951static unsigned int run_filter(struct sk_buff *skb,
1952 const struct sock *sk,
1953 unsigned int res)
1954{
1955 struct sk_filter *filter;
1956
1957 rcu_read_lock();
1958 filter = rcu_dereference(sk->sk_filter);
1959 if (filter != NULL)
1960 res = bpf_prog_run_clear_cb(filter->prog, skb);
1961 rcu_read_unlock();
1962
1963 return res;
1964}
1965
1966static int __packet_rcv_vnet(const struct sk_buff *skb,
1967 struct virtio_net_hdr *vnet_hdr)
1968{
1969 *vnet_hdr = (const struct virtio_net_hdr) { 0 };
1970
1971 if (skb_is_gso(skb)) {
1972 struct skb_shared_info *sinfo = skb_shinfo(skb);
1973
1974 /* This is a hint as to how much should be linear. */
1975 vnet_hdr->hdr_len =
1976 __cpu_to_virtio16(vio_le(), skb_headlen(skb));
1977 vnet_hdr->gso_size =
1978 __cpu_to_virtio16(vio_le(), sinfo->gso_size);
1979
1980 if (sinfo->gso_type & SKB_GSO_TCPV4)
1981 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1982 else if (sinfo->gso_type & SKB_GSO_TCPV6)
1983 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1984 else if (sinfo->gso_type & SKB_GSO_UDP)
1985 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
1986 else if (sinfo->gso_type & SKB_GSO_FCOE)
1987 return -EINVAL;
1988 else
1989 BUG();
1990
1991 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
1992 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1993 } else
1994 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
1995
1996 if (skb->ip_summed == CHECKSUM_PARTIAL) {
1997 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1998 vnet_hdr->csum_start = __cpu_to_virtio16(vio_le(),
1999 skb_checksum_start_offset(skb));
2000 vnet_hdr->csum_offset = __cpu_to_virtio16(vio_le(),
2001 skb->csum_offset);
2002 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2003 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
2004 } /* else everything is zero */
2005
2006 return 0;
2007}
2008
2009static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
2010 size_t *len)
2011{
2012 struct virtio_net_hdr vnet_hdr;
2013
2014 if (*len < sizeof(vnet_hdr))
2015 return -EINVAL;
2016 *len -= sizeof(vnet_hdr);
2017
2018 if (__packet_rcv_vnet(skb, &vnet_hdr))
2019 return -EINVAL;
2020
2021 return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
2022}
2023
2024/*
2025 * This function makes lazy skb cloning in hope that most of packets
2026 * are discarded by BPF.
2027 *
2028 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2029 * and skb->cb are mangled. It works because (and until) packets
2030 * falling here are owned by current CPU. Output packets are cloned
2031 * by dev_queue_xmit_nit(), input packets are processed by net_bh
2032 * sequencially, so that if we return skb to original state on exit,
2033 * we will not harm anyone.
2034 */
2035
2036static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2037 struct packet_type *pt, struct net_device *orig_dev)
2038{
2039 struct sock *sk;
2040 struct sockaddr_ll *sll;
2041 struct packet_sock *po;
2042 u8 *skb_head = skb->data;
2043 int skb_len = skb->len;
2044 unsigned int snaplen, res;
2045
2046 if (skb->pkt_type == PACKET_LOOPBACK)
2047 goto drop;
2048
2049 sk = pt->af_packet_priv;
2050 po = pkt_sk(sk);
2051
2052 if (!net_eq(dev_net(dev), sock_net(sk)))
2053 goto drop;
2054
2055 skb->dev = dev;
2056
2057 if (dev->header_ops) {
2058 /* The device has an explicit notion of ll header,
2059 * exported to higher levels.
2060 *
2061 * Otherwise, the device hides details of its frame
2062 * structure, so that corresponding packet head is
2063 * never delivered to user.
2064 */
2065 if (sk->sk_type != SOCK_DGRAM)
2066 skb_push(skb, skb->data - skb_mac_header(skb));
2067 else if (skb->pkt_type == PACKET_OUTGOING) {
2068 /* Special case: outgoing packets have ll header at head */
2069 skb_pull(skb, skb_network_offset(skb));
2070 }
2071 }
2072
2073 snaplen = skb->len;
2074
2075 res = run_filter(skb, sk, snaplen);
2076 if (!res)
2077 goto drop_n_restore;
2078 if (snaplen > res)
2079 snaplen = res;
2080
2081 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2082 goto drop_n_acct;
2083
2084 if (skb_shared(skb)) {
2085 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2086 if (nskb == NULL)
2087 goto drop_n_acct;
2088
2089 if (skb_head != skb->data) {
2090 skb->data = skb_head;
2091 skb->len = skb_len;
2092 }
2093 consume_skb(skb);
2094 skb = nskb;
2095 }
2096
2097 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2098
2099 sll = &PACKET_SKB_CB(skb)->sa.ll;
2100 sll->sll_hatype = dev->type;
2101 sll->sll_pkttype = skb->pkt_type;
2102 if (unlikely(po->origdev))
2103 sll->sll_ifindex = orig_dev->ifindex;
2104 else
2105 sll->sll_ifindex = dev->ifindex;
2106
2107 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2108
2109 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2110 * Use their space for storing the original skb length.
2111 */
2112 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2113
2114 if (pskb_trim(skb, snaplen))
2115 goto drop_n_acct;
2116
2117 skb_set_owner_r(skb, sk);
2118 skb->dev = NULL;
2119 skb_dst_drop(skb);
2120
2121 /* drop conntrack reference */
2122 nf_reset(skb);
2123
2124 spin_lock(&sk->sk_receive_queue.lock);
2125 po->stats.stats1.tp_packets++;
2126 sock_skb_set_dropcount(sk, skb);
2127 __skb_queue_tail(&sk->sk_receive_queue, skb);
2128 spin_unlock(&sk->sk_receive_queue.lock);
2129 sk->sk_data_ready(sk);
2130 return 0;
2131
2132drop_n_acct:
2133 spin_lock(&sk->sk_receive_queue.lock);
2134 po->stats.stats1.tp_drops++;
2135 atomic_inc(&sk->sk_drops);
2136 spin_unlock(&sk->sk_receive_queue.lock);
2137
2138drop_n_restore:
2139 if (skb_head != skb->data && skb_shared(skb)) {
2140 skb->data = skb_head;
2141 skb->len = skb_len;
2142 }
2143drop:
2144 consume_skb(skb);
2145 return 0;
2146}
2147
2148static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2149 struct packet_type *pt, struct net_device *orig_dev)
2150{
2151 struct sock *sk;
2152 struct packet_sock *po;
2153 struct sockaddr_ll *sll;
2154 union tpacket_uhdr h;
2155 u8 *skb_head = skb->data;
2156 int skb_len = skb->len;
2157 unsigned int snaplen, res;
2158 unsigned long status = TP_STATUS_USER;
2159 unsigned short macoff, netoff, hdrlen;
2160 struct sk_buff *copy_skb = NULL;
2161 struct timespec ts;
2162 __u32 ts_status;
2163
2164 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2165 * We may add members to them until current aligned size without forcing
2166 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2167 */
2168 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2169 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2170
2171 if (skb->pkt_type == PACKET_LOOPBACK)
2172 goto drop;
2173
2174 sk = pt->af_packet_priv;
2175 po = pkt_sk(sk);
2176
2177 if (!net_eq(dev_net(dev), sock_net(sk)))
2178 goto drop;
2179
2180 if (dev->header_ops) {
2181 if (sk->sk_type != SOCK_DGRAM)
2182 skb_push(skb, skb->data - skb_mac_header(skb));
2183 else if (skb->pkt_type == PACKET_OUTGOING) {
2184 /* Special case: outgoing packets have ll header at head */
2185 skb_pull(skb, skb_network_offset(skb));
2186 }
2187 }
2188
2189 snaplen = skb->len;
2190
2191 res = run_filter(skb, sk, snaplen);
2192 if (!res)
2193 goto drop_n_restore;
2194
2195 if (skb->ip_summed == CHECKSUM_PARTIAL)
2196 status |= TP_STATUS_CSUMNOTREADY;
2197 else if (skb->pkt_type != PACKET_OUTGOING &&
2198 (skb->ip_summed == CHECKSUM_COMPLETE ||
2199 skb_csum_unnecessary(skb)))
2200 status |= TP_STATUS_CSUM_VALID;
2201
2202 if (snaplen > res)
2203 snaplen = res;
2204
2205 if (sk->sk_type == SOCK_DGRAM) {
2206 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2207 po->tp_reserve;
2208 } else {
2209 unsigned int maclen = skb_network_offset(skb);
2210 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2211 (maclen < 16 ? 16 : maclen)) +
2212 po->tp_reserve;
2213 if (po->has_vnet_hdr)
2214 netoff += sizeof(struct virtio_net_hdr);
2215 macoff = netoff - maclen;
2216 }
2217 if (po->tp_version <= TPACKET_V2) {
2218 if (macoff + snaplen > po->rx_ring.frame_size) {
2219 if (po->copy_thresh &&
2220 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2221 if (skb_shared(skb)) {
2222 copy_skb = skb_clone(skb, GFP_ATOMIC);
2223 } else {
2224 copy_skb = skb_get(skb);
2225 skb_head = skb->data;
2226 }
2227 if (copy_skb)
2228 skb_set_owner_r(copy_skb, sk);
2229 }
2230 snaplen = po->rx_ring.frame_size - macoff;
2231 if ((int)snaplen < 0)
2232 snaplen = 0;
2233 }
2234 } else if (unlikely(macoff + snaplen >
2235 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2236 u32 nval;
2237
2238 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2239 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2240 snaplen, nval, macoff);
2241 snaplen = nval;
2242 if (unlikely((int)snaplen < 0)) {
2243 snaplen = 0;
2244 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2245 }
2246 }
2247 spin_lock(&sk->sk_receive_queue.lock);
2248 h.raw = packet_current_rx_frame(po, skb,
2249 TP_STATUS_KERNEL, (macoff+snaplen));
2250 if (!h.raw)
2251 goto drop_n_account;
2252 if (po->tp_version <= TPACKET_V2) {
2253 packet_increment_rx_head(po, &po->rx_ring);
2254 /*
2255 * LOSING will be reported till you read the stats,
2256 * because it's COR - Clear On Read.
2257 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2258 * at packet level.
2259 */
2260 if (po->stats.stats1.tp_drops)
2261 status |= TP_STATUS_LOSING;
2262 }
2263 po->stats.stats1.tp_packets++;
2264 if (copy_skb) {
2265 status |= TP_STATUS_COPY;
2266 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2267 }
2268 spin_unlock(&sk->sk_receive_queue.lock);
2269
2270 if (po->has_vnet_hdr) {
2271 if (__packet_rcv_vnet(skb, h.raw + macoff -
2272 sizeof(struct virtio_net_hdr))) {
2273 spin_lock(&sk->sk_receive_queue.lock);
2274 goto drop_n_account;
2275 }
2276 }
2277
2278 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2279
2280 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2281 getnstimeofday(&ts);
2282
2283 status |= ts_status;
2284
2285 switch (po->tp_version) {
2286 case TPACKET_V1:
2287 h.h1->tp_len = skb->len;
2288 h.h1->tp_snaplen = snaplen;
2289 h.h1->tp_mac = macoff;
2290 h.h1->tp_net = netoff;
2291 h.h1->tp_sec = ts.tv_sec;
2292 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2293 hdrlen = sizeof(*h.h1);
2294 break;
2295 case TPACKET_V2:
2296 h.h2->tp_len = skb->len;
2297 h.h2->tp_snaplen = snaplen;
2298 h.h2->tp_mac = macoff;
2299 h.h2->tp_net = netoff;
2300 h.h2->tp_sec = ts.tv_sec;
2301 h.h2->tp_nsec = ts.tv_nsec;
2302 if (skb_vlan_tag_present(skb)) {
2303 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2304 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2305 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2306 } else {
2307 h.h2->tp_vlan_tci = 0;
2308 h.h2->tp_vlan_tpid = 0;
2309 }
2310 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2311 hdrlen = sizeof(*h.h2);
2312 break;
2313 case TPACKET_V3:
2314 /* tp_nxt_offset,vlan are already populated above.
2315 * So DONT clear those fields here
2316 */
2317 h.h3->tp_status |= status;
2318 h.h3->tp_len = skb->len;
2319 h.h3->tp_snaplen = snaplen;
2320 h.h3->tp_mac = macoff;
2321 h.h3->tp_net = netoff;
2322 h.h3->tp_sec = ts.tv_sec;
2323 h.h3->tp_nsec = ts.tv_nsec;
2324 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2325 hdrlen = sizeof(*h.h3);
2326 break;
2327 default:
2328 BUG();
2329 }
2330
2331 sll = h.raw + TPACKET_ALIGN(hdrlen);
2332 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2333 sll->sll_family = AF_PACKET;
2334 sll->sll_hatype = dev->type;
2335 sll->sll_protocol = skb->protocol;
2336 sll->sll_pkttype = skb->pkt_type;
2337 if (unlikely(po->origdev))
2338 sll->sll_ifindex = orig_dev->ifindex;
2339 else
2340 sll->sll_ifindex = dev->ifindex;
2341
2342 smp_mb();
2343
2344#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2345 if (po->tp_version <= TPACKET_V2) {
2346 u8 *start, *end;
2347
2348 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2349 macoff + snaplen);
2350
2351 for (start = h.raw; start < end; start += PAGE_SIZE)
2352 flush_dcache_page(pgv_to_page(start));
2353 }
2354 smp_wmb();
2355#endif
2356
2357 if (po->tp_version <= TPACKET_V2) {
2358 __packet_set_status(po, h.raw, status);
2359 sk->sk_data_ready(sk);
2360 } else {
2361 prb_clear_blk_fill_status(&po->rx_ring);
2362 }
2363
2364drop_n_restore:
2365 if (skb_head != skb->data && skb_shared(skb)) {
2366 skb->data = skb_head;
2367 skb->len = skb_len;
2368 }
2369drop:
2370 kfree_skb(skb);
2371 return 0;
2372
2373drop_n_account:
2374 po->stats.stats1.tp_drops++;
2375 spin_unlock(&sk->sk_receive_queue.lock);
2376
2377 sk->sk_data_ready(sk);
2378 kfree_skb(copy_skb);
2379 goto drop_n_restore;
2380}
2381
2382static void tpacket_destruct_skb(struct sk_buff *skb)
2383{
2384 struct packet_sock *po = pkt_sk(skb->sk);
2385
2386 if (likely(po->tx_ring.pg_vec)) {
2387 void *ph;
2388 __u32 ts;
2389
2390 ph = skb_shinfo(skb)->destructor_arg;
2391 packet_dec_pending(&po->tx_ring);
2392
2393 ts = __packet_set_timestamp(po, ph, skb);
2394 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2395 }
2396
2397 sock_wfree(skb);
2398}
2399
2400static void tpacket_set_protocol(const struct net_device *dev,
2401 struct sk_buff *skb)
2402{
2403 if (dev->type == ARPHRD_ETHER) {
2404 skb_reset_mac_header(skb);
2405 skb->protocol = eth_hdr(skb)->h_proto;
2406 }
2407}
2408
2409static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2410{
2411 unsigned short gso_type = 0;
2412
2413 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2414 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2415 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2416 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2417 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2418 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2419 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2420
2421 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2422 return -EINVAL;
2423
2424 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2425 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2426 case VIRTIO_NET_HDR_GSO_TCPV4:
2427 gso_type = SKB_GSO_TCPV4;
2428 break;
2429 case VIRTIO_NET_HDR_GSO_TCPV6:
2430 gso_type = SKB_GSO_TCPV6;
2431 break;
2432 case VIRTIO_NET_HDR_GSO_UDP:
2433 gso_type = SKB_GSO_UDP;
2434 break;
2435 default:
2436 return -EINVAL;
2437 }
2438
2439 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
2440 gso_type |= SKB_GSO_TCP_ECN;
2441
2442 if (vnet_hdr->gso_size == 0)
2443 return -EINVAL;
2444 }
2445
2446 vnet_hdr->gso_type = gso_type; /* changes type, temporary storage */
2447 return 0;
2448}
2449
2450static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2451 struct virtio_net_hdr *vnet_hdr)
2452{
2453 int n;
2454
2455 if (*len < sizeof(*vnet_hdr))
2456 return -EINVAL;
2457 *len -= sizeof(*vnet_hdr);
2458
2459 n = copy_from_iter(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter);
2460 if (n != sizeof(*vnet_hdr))
2461 return -EFAULT;
2462
2463 return __packet_snd_vnet_parse(vnet_hdr, *len);
2464}
2465
2466static int packet_snd_vnet_gso(struct sk_buff *skb,
2467 struct virtio_net_hdr *vnet_hdr)
2468{
2469 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2470 u16 s = __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start);
2471 u16 o = __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset);
2472
2473 if (!skb_partial_csum_set(skb, s, o))
2474 return -EINVAL;
2475 }
2476
2477 skb_shinfo(skb)->gso_size =
2478 __virtio16_to_cpu(vio_le(), vnet_hdr->gso_size);
2479 skb_shinfo(skb)->gso_type = vnet_hdr->gso_type;
2480
2481 /* Header must be checked, and gso_segs computed. */
2482 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2483 skb_shinfo(skb)->gso_segs = 0;
2484 return 0;
2485}
2486
2487static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2488 void *frame, struct net_device *dev, void *data, int tp_len,
2489 __be16 proto, unsigned char *addr, int hlen, int copylen)
2490{
2491 union tpacket_uhdr ph;
2492 int to_write, offset, len, nr_frags, len_max;
2493 struct socket *sock = po->sk.sk_socket;
2494 struct page *page;
2495 int err;
2496
2497 ph.raw = frame;
2498
2499 skb->protocol = proto;
2500 skb->dev = dev;
2501 skb->priority = po->sk.sk_priority;
2502 skb->mark = po->sk.sk_mark;
2503 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2504 skb_shinfo(skb)->destructor_arg = ph.raw;
2505
2506 skb_reserve(skb, hlen);
2507 skb_reset_network_header(skb);
2508
2509 to_write = tp_len;
2510
2511 if (sock->type == SOCK_DGRAM) {
2512 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2513 NULL, tp_len);
2514 if (unlikely(err < 0))
2515 return -EINVAL;
2516 } else if (copylen) {
2517 int hdrlen = min_t(int, copylen, tp_len);
2518
2519 skb_push(skb, dev->hard_header_len);
2520 skb_put(skb, copylen - dev->hard_header_len);
2521 err = skb_store_bits(skb, 0, data, hdrlen);
2522 if (unlikely(err))
2523 return err;
2524 if (!dev_validate_header(dev, skb->data, hdrlen))
2525 return -EINVAL;
2526 if (!skb->protocol)
2527 tpacket_set_protocol(dev, skb);
2528
2529 data += hdrlen;
2530 to_write -= hdrlen;
2531 }
2532
2533 offset = offset_in_page(data);
2534 len_max = PAGE_SIZE - offset;
2535 len = ((to_write > len_max) ? len_max : to_write);
2536
2537 skb->data_len = to_write;
2538 skb->len += to_write;
2539 skb->truesize += to_write;
2540 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2541
2542 while (likely(to_write)) {
2543 nr_frags = skb_shinfo(skb)->nr_frags;
2544
2545 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2546 pr_err("Packet exceed the number of skb frags(%lu)\n",
2547 MAX_SKB_FRAGS);
2548 return -EFAULT;
2549 }
2550
2551 page = pgv_to_page(data);
2552 data += len;
2553 flush_dcache_page(page);
2554 get_page(page);
2555 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2556 to_write -= len;
2557 offset = 0;
2558 len_max = PAGE_SIZE;
2559 len = ((to_write > len_max) ? len_max : to_write);
2560 }
2561
2562 skb_probe_transport_header(skb, 0);
2563
2564 return tp_len;
2565}
2566
2567static int tpacket_parse_header(struct packet_sock *po, void *frame,
2568 int size_max, void **data)
2569{
2570 union tpacket_uhdr ph;
2571 int tp_len, off;
2572
2573 ph.raw = frame;
2574
2575 switch (po->tp_version) {
2576 case TPACKET_V2:
2577 tp_len = ph.h2->tp_len;
2578 break;
2579 default:
2580 tp_len = ph.h1->tp_len;
2581 break;
2582 }
2583 if (unlikely(tp_len > size_max)) {
2584 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2585 return -EMSGSIZE;
2586 }
2587
2588 if (unlikely(po->tp_tx_has_off)) {
2589 int off_min, off_max;
2590
2591 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2592 off_max = po->tx_ring.frame_size - tp_len;
2593 if (po->sk.sk_type == SOCK_DGRAM) {
2594 switch (po->tp_version) {
2595 case TPACKET_V2:
2596 off = ph.h2->tp_net;
2597 break;
2598 default:
2599 off = ph.h1->tp_net;
2600 break;
2601 }
2602 } else {
2603 switch (po->tp_version) {
2604 case TPACKET_V2:
2605 off = ph.h2->tp_mac;
2606 break;
2607 default:
2608 off = ph.h1->tp_mac;
2609 break;
2610 }
2611 }
2612 if (unlikely((off < off_min) || (off_max < off)))
2613 return -EINVAL;
2614 } else {
2615 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2616 }
2617
2618 *data = frame + off;
2619 return tp_len;
2620}
2621
2622static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2623{
2624 struct sk_buff *skb;
2625 struct net_device *dev;
2626 struct virtio_net_hdr *vnet_hdr = NULL;
2627 __be16 proto;
2628 int err, reserve = 0;
2629 void *ph;
2630 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2631 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2632 int tp_len, size_max;
2633 unsigned char *addr;
2634 void *data;
2635 int len_sum = 0;
2636 int status = TP_STATUS_AVAILABLE;
2637 int hlen, tlen, copylen = 0;
2638
2639 mutex_lock(&po->pg_vec_lock);
2640
2641 if (likely(saddr == NULL)) {
2642 dev = packet_cached_dev_get(po);
2643 proto = po->num;
2644 addr = NULL;
2645 } else {
2646 err = -EINVAL;
2647 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2648 goto out;
2649 if (msg->msg_namelen < (saddr->sll_halen
2650 + offsetof(struct sockaddr_ll,
2651 sll_addr)))
2652 goto out;
2653 proto = saddr->sll_protocol;
2654 addr = saddr->sll_addr;
2655 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2656 }
2657
2658 err = -ENXIO;
2659 if (unlikely(dev == NULL))
2660 goto out;
2661 err = -ENETDOWN;
2662 if (unlikely(!(dev->flags & IFF_UP)))
2663 goto out_put;
2664
2665 if (po->sk.sk_socket->type == SOCK_RAW)
2666 reserve = dev->hard_header_len;
2667 size_max = po->tx_ring.frame_size
2668 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2669
2670 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2671 size_max = dev->mtu + reserve + VLAN_HLEN;
2672
2673 do {
2674 ph = packet_current_frame(po, &po->tx_ring,
2675 TP_STATUS_SEND_REQUEST);
2676 if (unlikely(ph == NULL)) {
2677 if (need_wait && need_resched())
2678 schedule();
2679 continue;
2680 }
2681
2682 skb = NULL;
2683 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2684 if (tp_len < 0)
2685 goto tpacket_error;
2686
2687 status = TP_STATUS_SEND_REQUEST;
2688 hlen = LL_RESERVED_SPACE(dev);
2689 tlen = dev->needed_tailroom;
2690 if (po->has_vnet_hdr) {
2691 vnet_hdr = data;
2692 data += sizeof(*vnet_hdr);
2693 tp_len -= sizeof(*vnet_hdr);
2694 if (tp_len < 0 ||
2695 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2696 tp_len = -EINVAL;
2697 goto tpacket_error;
2698 }
2699 copylen = __virtio16_to_cpu(vio_le(),
2700 vnet_hdr->hdr_len);
2701 }
2702 copylen = max_t(int, copylen, dev->hard_header_len);
2703 skb = sock_alloc_send_skb(&po->sk,
2704 hlen + tlen + sizeof(struct sockaddr_ll) +
2705 (copylen - dev->hard_header_len),
2706 !need_wait, &err);
2707
2708 if (unlikely(skb == NULL)) {
2709 /* we assume the socket was initially writeable ... */
2710 if (likely(len_sum > 0))
2711 err = len_sum;
2712 goto out_status;
2713 }
2714 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2715 addr, hlen, copylen);
2716 if (likely(tp_len >= 0) &&
2717 tp_len > dev->mtu + reserve &&
2718 !po->has_vnet_hdr &&
2719 !packet_extra_vlan_len_allowed(dev, skb))
2720 tp_len = -EMSGSIZE;
2721
2722 if (unlikely(tp_len < 0)) {
2723tpacket_error:
2724 if (po->tp_loss) {
2725 __packet_set_status(po, ph,
2726 TP_STATUS_AVAILABLE);
2727 packet_increment_head(&po->tx_ring);
2728 kfree_skb(skb);
2729 continue;
2730 } else {
2731 status = TP_STATUS_WRONG_FORMAT;
2732 err = tp_len;
2733 goto out_status;
2734 }
2735 }
2736
2737 if (po->has_vnet_hdr && packet_snd_vnet_gso(skb, vnet_hdr)) {
2738 tp_len = -EINVAL;
2739 goto tpacket_error;
2740 }
2741
2742 packet_pick_tx_queue(dev, skb);
2743
2744 skb->destructor = tpacket_destruct_skb;
2745 __packet_set_status(po, ph, TP_STATUS_SENDING);
2746 packet_inc_pending(&po->tx_ring);
2747
2748 status = TP_STATUS_SEND_REQUEST;
2749 err = po->xmit(skb);
2750 if (unlikely(err > 0)) {
2751 err = net_xmit_errno(err);
2752 if (err && __packet_get_status(po, ph) ==
2753 TP_STATUS_AVAILABLE) {
2754 /* skb was destructed already */
2755 skb = NULL;
2756 goto out_status;
2757 }
2758 /*
2759 * skb was dropped but not destructed yet;
2760 * let's treat it like congestion or err < 0
2761 */
2762 err = 0;
2763 }
2764 packet_increment_head(&po->tx_ring);
2765 len_sum += tp_len;
2766 } while (likely((ph != NULL) ||
2767 /* Note: packet_read_pending() might be slow if we have
2768 * to call it as it's per_cpu variable, but in fast-path
2769 * we already short-circuit the loop with the first
2770 * condition, and luckily don't have to go that path
2771 * anyway.
2772 */
2773 (need_wait && packet_read_pending(&po->tx_ring))));
2774
2775 err = len_sum;
2776 goto out_put;
2777
2778out_status:
2779 __packet_set_status(po, ph, status);
2780 kfree_skb(skb);
2781out_put:
2782 dev_put(dev);
2783out:
2784 mutex_unlock(&po->pg_vec_lock);
2785 return err;
2786}
2787
2788static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2789 size_t reserve, size_t len,
2790 size_t linear, int noblock,
2791 int *err)
2792{
2793 struct sk_buff *skb;
2794
2795 /* Under a page? Don't bother with paged skb. */
2796 if (prepad + len < PAGE_SIZE || !linear)
2797 linear = len;
2798
2799 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2800 err, 0);
2801 if (!skb)
2802 return NULL;
2803
2804 skb_reserve(skb, reserve);
2805 skb_put(skb, linear);
2806 skb->data_len = len - linear;
2807 skb->len += len - linear;
2808
2809 return skb;
2810}
2811
2812static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2813{
2814 struct sock *sk = sock->sk;
2815 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2816 struct sk_buff *skb;
2817 struct net_device *dev;
2818 __be16 proto;
2819 unsigned char *addr;
2820 int err, reserve = 0;
2821 struct sockcm_cookie sockc;
2822 struct virtio_net_hdr vnet_hdr = { 0 };
2823 int offset = 0;
2824 struct packet_sock *po = pkt_sk(sk);
2825 int hlen, tlen;
2826 int extra_len = 0;
2827
2828 /*
2829 * Get and verify the address.
2830 */
2831
2832 if (likely(saddr == NULL)) {
2833 dev = packet_cached_dev_get(po);
2834 proto = po->num;
2835 addr = NULL;
2836 } else {
2837 err = -EINVAL;
2838 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2839 goto out;
2840 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2841 goto out;
2842 proto = saddr->sll_protocol;
2843 addr = saddr->sll_addr;
2844 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2845 }
2846
2847 err = -ENXIO;
2848 if (unlikely(dev == NULL))
2849 goto out_unlock;
2850 err = -ENETDOWN;
2851 if (unlikely(!(dev->flags & IFF_UP)))
2852 goto out_unlock;
2853
2854 sockc.mark = sk->sk_mark;
2855 if (msg->msg_controllen) {
2856 err = sock_cmsg_send(sk, msg, &sockc);
2857 if (unlikely(err))
2858 goto out_unlock;
2859 }
2860
2861 if (sock->type == SOCK_RAW)
2862 reserve = dev->hard_header_len;
2863 if (po->has_vnet_hdr) {
2864 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2865 if (err)
2866 goto out_unlock;
2867 }
2868
2869 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2870 if (!netif_supports_nofcs(dev)) {
2871 err = -EPROTONOSUPPORT;
2872 goto out_unlock;
2873 }
2874 extra_len = 4; /* We're doing our own CRC */
2875 }
2876
2877 err = -EMSGSIZE;
2878 if (!vnet_hdr.gso_type &&
2879 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2880 goto out_unlock;
2881
2882 err = -ENOBUFS;
2883 hlen = LL_RESERVED_SPACE(dev);
2884 tlen = dev->needed_tailroom;
2885 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2886 __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len),
2887 msg->msg_flags & MSG_DONTWAIT, &err);
2888 if (skb == NULL)
2889 goto out_unlock;
2890
2891 skb_set_network_header(skb, reserve);
2892
2893 err = -EINVAL;
2894 if (sock->type == SOCK_DGRAM) {
2895 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2896 if (unlikely(offset < 0))
2897 goto out_free;
2898 }
2899
2900 /* Returns -EFAULT on error */
2901 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2902 if (err)
2903 goto out_free;
2904
2905 if (sock->type == SOCK_RAW &&
2906 !dev_validate_header(dev, skb->data, len)) {
2907 err = -EINVAL;
2908 goto out_free;
2909 }
2910
2911 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2912
2913 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
2914 !packet_extra_vlan_len_allowed(dev, skb)) {
2915 err = -EMSGSIZE;
2916 goto out_free;
2917 }
2918
2919 skb->protocol = proto;
2920 skb->dev = dev;
2921 skb->priority = sk->sk_priority;
2922 skb->mark = sockc.mark;
2923
2924 packet_pick_tx_queue(dev, skb);
2925
2926 if (po->has_vnet_hdr) {
2927 err = packet_snd_vnet_gso(skb, &vnet_hdr);
2928 if (err)
2929 goto out_free;
2930 len += sizeof(vnet_hdr);
2931 }
2932
2933 skb_probe_transport_header(skb, reserve);
2934
2935 if (unlikely(extra_len == 4))
2936 skb->no_fcs = 1;
2937
2938 err = po->xmit(skb);
2939 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2940 goto out_unlock;
2941
2942 dev_put(dev);
2943
2944 return len;
2945
2946out_free:
2947 kfree_skb(skb);
2948out_unlock:
2949 if (dev)
2950 dev_put(dev);
2951out:
2952 return err;
2953}
2954
2955static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2956{
2957 struct sock *sk = sock->sk;
2958 struct packet_sock *po = pkt_sk(sk);
2959
2960 if (po->tx_ring.pg_vec)
2961 return tpacket_snd(po, msg);
2962 else
2963 return packet_snd(sock, msg, len);
2964}
2965
2966/*
2967 * Close a PACKET socket. This is fairly simple. We immediately go
2968 * to 'closed' state and remove our protocol entry in the device list.
2969 */
2970
2971static int packet_release(struct socket *sock)
2972{
2973 struct sock *sk = sock->sk;
2974 struct packet_sock *po;
2975 struct net *net;
2976 union tpacket_req_u req_u;
2977
2978 if (!sk)
2979 return 0;
2980
2981 net = sock_net(sk);
2982 po = pkt_sk(sk);
2983
2984 mutex_lock(&net->packet.sklist_lock);
2985 sk_del_node_init_rcu(sk);
2986 mutex_unlock(&net->packet.sklist_lock);
2987
2988 preempt_disable();
2989 sock_prot_inuse_add(net, sk->sk_prot, -1);
2990 preempt_enable();
2991
2992 spin_lock(&po->bind_lock);
2993 unregister_prot_hook(sk, false);
2994 packet_cached_dev_reset(po);
2995
2996 if (po->prot_hook.dev) {
2997 dev_put(po->prot_hook.dev);
2998 po->prot_hook.dev = NULL;
2999 }
3000 spin_unlock(&po->bind_lock);
3001
3002 packet_flush_mclist(sk);
3003
3004 if (po->rx_ring.pg_vec) {
3005 memset(&req_u, 0, sizeof(req_u));
3006 packet_set_ring(sk, &req_u, 1, 0);
3007 }
3008
3009 if (po->tx_ring.pg_vec) {
3010 memset(&req_u, 0, sizeof(req_u));
3011 packet_set_ring(sk, &req_u, 1, 1);
3012 }
3013
3014 fanout_release(sk);
3015
3016 synchronize_net();
3017 /*
3018 * Now the socket is dead. No more input will appear.
3019 */
3020 sock_orphan(sk);
3021 sock->sk = NULL;
3022
3023 /* Purge queues */
3024
3025 skb_queue_purge(&sk->sk_receive_queue);
3026 packet_free_pending(po);
3027 sk_refcnt_debug_release(sk);
3028
3029 sock_put(sk);
3030 return 0;
3031}
3032
3033/*
3034 * Attach a packet hook.
3035 */
3036
3037static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
3038 __be16 proto)
3039{
3040 struct packet_sock *po = pkt_sk(sk);
3041 struct net_device *dev_curr;
3042 __be16 proto_curr;
3043 bool need_rehook;
3044 struct net_device *dev = NULL;
3045 int ret = 0;
3046 bool unlisted = false;
3047
3048 if (po->fanout)
3049 return -EINVAL;
3050
3051 lock_sock(sk);
3052 spin_lock(&po->bind_lock);
3053 rcu_read_lock();
3054
3055 if (name) {
3056 dev = dev_get_by_name_rcu(sock_net(sk), name);
3057 if (!dev) {
3058 ret = -ENODEV;
3059 goto out_unlock;
3060 }
3061 } else if (ifindex) {
3062 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3063 if (!dev) {
3064 ret = -ENODEV;
3065 goto out_unlock;
3066 }
3067 }
3068
3069 if (dev)
3070 dev_hold(dev);
3071
3072 proto_curr = po->prot_hook.type;
3073 dev_curr = po->prot_hook.dev;
3074
3075 need_rehook = proto_curr != proto || dev_curr != dev;
3076
3077 if (need_rehook) {
3078 if (po->running) {
3079 rcu_read_unlock();
3080 __unregister_prot_hook(sk, true);
3081 rcu_read_lock();
3082 dev_curr = po->prot_hook.dev;
3083 if (dev)
3084 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3085 dev->ifindex);
3086 }
3087
3088 po->num = proto;
3089 po->prot_hook.type = proto;
3090
3091 if (unlikely(unlisted)) {
3092 dev_put(dev);
3093 po->prot_hook.dev = NULL;
3094 po->ifindex = -1;
3095 packet_cached_dev_reset(po);
3096 } else {
3097 po->prot_hook.dev = dev;
3098 po->ifindex = dev ? dev->ifindex : 0;
3099 packet_cached_dev_assign(po, dev);
3100 }
3101 }
3102 if (dev_curr)
3103 dev_put(dev_curr);
3104
3105 if (proto == 0 || !need_rehook)
3106 goto out_unlock;
3107
3108 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3109 register_prot_hook(sk);
3110 } else {
3111 sk->sk_err = ENETDOWN;
3112 if (!sock_flag(sk, SOCK_DEAD))
3113 sk->sk_error_report(sk);
3114 }
3115
3116out_unlock:
3117 rcu_read_unlock();
3118 spin_unlock(&po->bind_lock);
3119 release_sock(sk);
3120 return ret;
3121}
3122
3123/*
3124 * Bind a packet socket to a device
3125 */
3126
3127static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3128 int addr_len)
3129{
3130 struct sock *sk = sock->sk;
3131 char name[15];
3132
3133 /*
3134 * Check legality
3135 */
3136
3137 if (addr_len != sizeof(struct sockaddr))
3138 return -EINVAL;
3139 strlcpy(name, uaddr->sa_data, sizeof(name));
3140
3141 return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3142}
3143
3144static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3145{
3146 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3147 struct sock *sk = sock->sk;
3148
3149 /*
3150 * Check legality
3151 */
3152
3153 if (addr_len < sizeof(struct sockaddr_ll))
3154 return -EINVAL;
3155 if (sll->sll_family != AF_PACKET)
3156 return -EINVAL;
3157
3158 return packet_do_bind(sk, NULL, sll->sll_ifindex,
3159 sll->sll_protocol ? : pkt_sk(sk)->num);
3160}
3161
3162static struct proto packet_proto = {
3163 .name = "PACKET",
3164 .owner = THIS_MODULE,
3165 .obj_size = sizeof(struct packet_sock),
3166};
3167
3168/*
3169 * Create a packet of type SOCK_PACKET.
3170 */
3171
3172static int packet_create(struct net *net, struct socket *sock, int protocol,
3173 int kern)
3174{
3175 struct sock *sk;
3176 struct packet_sock *po;
3177 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3178 int err;
3179
3180 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3181 return -EPERM;
3182 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3183 sock->type != SOCK_PACKET)
3184 return -ESOCKTNOSUPPORT;
3185
3186 sock->state = SS_UNCONNECTED;
3187
3188 err = -ENOBUFS;
3189 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3190 if (sk == NULL)
3191 goto out;
3192
3193 sock->ops = &packet_ops;
3194 if (sock->type == SOCK_PACKET)
3195 sock->ops = &packet_ops_spkt;
3196
3197 sock_init_data(sock, sk);
3198
3199 po = pkt_sk(sk);
3200 sk->sk_family = PF_PACKET;
3201 po->num = proto;
3202 po->xmit = dev_queue_xmit;
3203
3204 err = packet_alloc_pending(po);
3205 if (err)
3206 goto out2;
3207
3208 packet_cached_dev_reset(po);
3209
3210 sk->sk_destruct = packet_sock_destruct;
3211 sk_refcnt_debug_inc(sk);
3212
3213 /*
3214 * Attach a protocol block
3215 */
3216
3217 spin_lock_init(&po->bind_lock);
3218 mutex_init(&po->pg_vec_lock);
3219 po->rollover = NULL;
3220 po->prot_hook.func = packet_rcv;
3221
3222 if (sock->type == SOCK_PACKET)
3223 po->prot_hook.func = packet_rcv_spkt;
3224
3225 po->prot_hook.af_packet_priv = sk;
3226
3227 if (proto) {
3228 po->prot_hook.type = proto;
3229 register_prot_hook(sk);
3230 }
3231
3232 mutex_lock(&net->packet.sklist_lock);
3233 sk_add_node_rcu(sk, &net->packet.sklist);
3234 mutex_unlock(&net->packet.sklist_lock);
3235
3236 preempt_disable();
3237 sock_prot_inuse_add(net, &packet_proto, 1);
3238 preempt_enable();
3239
3240 return 0;
3241out2:
3242 sk_free(sk);
3243out:
3244 return err;
3245}
3246
3247/*
3248 * Pull a packet from our receive queue and hand it to the user.
3249 * If necessary we block.
3250 */
3251
3252static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3253 int flags)
3254{
3255 struct sock *sk = sock->sk;
3256 struct sk_buff *skb;
3257 int copied, err;
3258 int vnet_hdr_len = 0;
3259 unsigned int origlen = 0;
3260
3261 err = -EINVAL;
3262 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3263 goto out;
3264
3265#if 0
3266 /* What error should we return now? EUNATTACH? */
3267 if (pkt_sk(sk)->ifindex < 0)
3268 return -ENODEV;
3269#endif
3270
3271 if (flags & MSG_ERRQUEUE) {
3272 err = sock_recv_errqueue(sk, msg, len,
3273 SOL_PACKET, PACKET_TX_TIMESTAMP);
3274 goto out;
3275 }
3276
3277 /*
3278 * Call the generic datagram receiver. This handles all sorts
3279 * of horrible races and re-entrancy so we can forget about it
3280 * in the protocol layers.
3281 *
3282 * Now it will return ENETDOWN, if device have just gone down,
3283 * but then it will block.
3284 */
3285
3286 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3287
3288 /*
3289 * An error occurred so return it. Because skb_recv_datagram()
3290 * handles the blocking we don't see and worry about blocking
3291 * retries.
3292 */
3293
3294 if (skb == NULL)
3295 goto out;
3296
3297 if (pkt_sk(sk)->pressure)
3298 packet_rcv_has_room(pkt_sk(sk), NULL);
3299
3300 if (pkt_sk(sk)->has_vnet_hdr) {
3301 err = packet_rcv_vnet(msg, skb, &len);
3302 if (err)
3303 goto out_free;
3304 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3305 }
3306
3307 /* You lose any data beyond the buffer you gave. If it worries
3308 * a user program they can ask the device for its MTU
3309 * anyway.
3310 */
3311 copied = skb->len;
3312 if (copied > len) {
3313 copied = len;
3314 msg->msg_flags |= MSG_TRUNC;
3315 }
3316
3317 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3318 if (err)
3319 goto out_free;
3320
3321 if (sock->type != SOCK_PACKET) {
3322 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3323
3324 /* Original length was stored in sockaddr_ll fields */
3325 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3326 sll->sll_family = AF_PACKET;
3327 sll->sll_protocol = skb->protocol;
3328 }
3329
3330 sock_recv_ts_and_drops(msg, sk, skb);
3331
3332 if (msg->msg_name) {
3333 /* If the address length field is there to be filled
3334 * in, we fill it in now.
3335 */
3336 if (sock->type == SOCK_PACKET) {
3337 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3338 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3339 } else {
3340 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3341
3342 msg->msg_namelen = sll->sll_halen +
3343 offsetof(struct sockaddr_ll, sll_addr);
3344 }
3345 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3346 msg->msg_namelen);
3347 }
3348
3349 if (pkt_sk(sk)->auxdata) {
3350 struct tpacket_auxdata aux;
3351
3352 aux.tp_status = TP_STATUS_USER;
3353 if (skb->ip_summed == CHECKSUM_PARTIAL)
3354 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3355 else if (skb->pkt_type != PACKET_OUTGOING &&
3356 (skb->ip_summed == CHECKSUM_COMPLETE ||
3357 skb_csum_unnecessary(skb)))
3358 aux.tp_status |= TP_STATUS_CSUM_VALID;
3359
3360 aux.tp_len = origlen;
3361 aux.tp_snaplen = skb->len;
3362 aux.tp_mac = 0;
3363 aux.tp_net = skb_network_offset(skb);
3364 if (skb_vlan_tag_present(skb)) {
3365 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3366 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3367 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3368 } else {
3369 aux.tp_vlan_tci = 0;
3370 aux.tp_vlan_tpid = 0;
3371 }
3372 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3373 }
3374
3375 /*
3376 * Free or return the buffer as appropriate. Again this
3377 * hides all the races and re-entrancy issues from us.
3378 */
3379 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3380
3381out_free:
3382 skb_free_datagram(sk, skb);
3383out:
3384 return err;
3385}
3386
3387static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3388 int *uaddr_len, int peer)
3389{
3390 struct net_device *dev;
3391 struct sock *sk = sock->sk;
3392
3393 if (peer)
3394 return -EOPNOTSUPP;
3395
3396 uaddr->sa_family = AF_PACKET;
3397 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3398 rcu_read_lock();
3399 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3400 if (dev)
3401 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3402 rcu_read_unlock();
3403 *uaddr_len = sizeof(*uaddr);
3404
3405 return 0;
3406}
3407
3408static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3409 int *uaddr_len, int peer)
3410{
3411 struct net_device *dev;
3412 struct sock *sk = sock->sk;
3413 struct packet_sock *po = pkt_sk(sk);
3414 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3415
3416 if (peer)
3417 return -EOPNOTSUPP;
3418
3419 sll->sll_family = AF_PACKET;
3420 sll->sll_ifindex = po->ifindex;
3421 sll->sll_protocol = po->num;
3422 sll->sll_pkttype = 0;
3423 rcu_read_lock();
3424 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3425 if (dev) {
3426 sll->sll_hatype = dev->type;
3427 sll->sll_halen = dev->addr_len;
3428 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3429 } else {
3430 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3431 sll->sll_halen = 0;
3432 }
3433 rcu_read_unlock();
3434 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3435
3436 return 0;
3437}
3438
3439static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3440 int what)
3441{
3442 switch (i->type) {
3443 case PACKET_MR_MULTICAST:
3444 if (i->alen != dev->addr_len)
3445 return -EINVAL;
3446 if (what > 0)
3447 return dev_mc_add(dev, i->addr);
3448 else
3449 return dev_mc_del(dev, i->addr);
3450 break;
3451 case PACKET_MR_PROMISC:
3452 return dev_set_promiscuity(dev, what);
3453 case PACKET_MR_ALLMULTI:
3454 return dev_set_allmulti(dev, what);
3455 case PACKET_MR_UNICAST:
3456 if (i->alen != dev->addr_len)
3457 return -EINVAL;
3458 if (what > 0)
3459 return dev_uc_add(dev, i->addr);
3460 else
3461 return dev_uc_del(dev, i->addr);
3462 break;
3463 default:
3464 break;
3465 }
3466 return 0;
3467}
3468
3469static void packet_dev_mclist_delete(struct net_device *dev,
3470 struct packet_mclist **mlp)
3471{
3472 struct packet_mclist *ml;
3473
3474 while ((ml = *mlp) != NULL) {
3475 if (ml->ifindex == dev->ifindex) {
3476 packet_dev_mc(dev, ml, -1);
3477 *mlp = ml->next;
3478 kfree(ml);
3479 } else
3480 mlp = &ml->next;
3481 }
3482}
3483
3484static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3485{
3486 struct packet_sock *po = pkt_sk(sk);
3487 struct packet_mclist *ml, *i;
3488 struct net_device *dev;
3489 int err;
3490
3491 rtnl_lock();
3492
3493 err = -ENODEV;
3494 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3495 if (!dev)
3496 goto done;
3497
3498 err = -EINVAL;
3499 if (mreq->mr_alen > dev->addr_len)
3500 goto done;
3501
3502 err = -ENOBUFS;
3503 i = kmalloc(sizeof(*i), GFP_KERNEL);
3504 if (i == NULL)
3505 goto done;
3506
3507 err = 0;
3508 for (ml = po->mclist; ml; ml = ml->next) {
3509 if (ml->ifindex == mreq->mr_ifindex &&
3510 ml->type == mreq->mr_type &&
3511 ml->alen == mreq->mr_alen &&
3512 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3513 ml->count++;
3514 /* Free the new element ... */
3515 kfree(i);
3516 goto done;
3517 }
3518 }
3519
3520 i->type = mreq->mr_type;
3521 i->ifindex = mreq->mr_ifindex;
3522 i->alen = mreq->mr_alen;
3523 memcpy(i->addr, mreq->mr_address, i->alen);
3524 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3525 i->count = 1;
3526 i->next = po->mclist;
3527 po->mclist = i;
3528 err = packet_dev_mc(dev, i, 1);
3529 if (err) {
3530 po->mclist = i->next;
3531 kfree(i);
3532 }
3533
3534done:
3535 rtnl_unlock();
3536 return err;
3537}
3538
3539static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3540{
3541 struct packet_mclist *ml, **mlp;
3542
3543 rtnl_lock();
3544
3545 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3546 if (ml->ifindex == mreq->mr_ifindex &&
3547 ml->type == mreq->mr_type &&
3548 ml->alen == mreq->mr_alen &&
3549 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3550 if (--ml->count == 0) {
3551 struct net_device *dev;
3552 *mlp = ml->next;
3553 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3554 if (dev)
3555 packet_dev_mc(dev, ml, -1);
3556 kfree(ml);
3557 }
3558 break;
3559 }
3560 }
3561 rtnl_unlock();
3562 return 0;
3563}
3564
3565static void packet_flush_mclist(struct sock *sk)
3566{
3567 struct packet_sock *po = pkt_sk(sk);
3568 struct packet_mclist *ml;
3569
3570 if (!po->mclist)
3571 return;
3572
3573 rtnl_lock();
3574 while ((ml = po->mclist) != NULL) {
3575 struct net_device *dev;
3576
3577 po->mclist = ml->next;
3578 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3579 if (dev != NULL)
3580 packet_dev_mc(dev, ml, -1);
3581 kfree(ml);
3582 }
3583 rtnl_unlock();
3584}
3585
3586static int
3587packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3588{
3589 struct sock *sk = sock->sk;
3590 struct packet_sock *po = pkt_sk(sk);
3591 int ret;
3592
3593 if (level != SOL_PACKET)
3594 return -ENOPROTOOPT;
3595
3596 switch (optname) {
3597 case PACKET_ADD_MEMBERSHIP:
3598 case PACKET_DROP_MEMBERSHIP:
3599 {
3600 struct packet_mreq_max mreq;
3601 int len = optlen;
3602 memset(&mreq, 0, sizeof(mreq));
3603 if (len < sizeof(struct packet_mreq))
3604 return -EINVAL;
3605 if (len > sizeof(mreq))
3606 len = sizeof(mreq);
3607 if (copy_from_user(&mreq, optval, len))
3608 return -EFAULT;
3609 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3610 return -EINVAL;
3611 if (optname == PACKET_ADD_MEMBERSHIP)
3612 ret = packet_mc_add(sk, &mreq);
3613 else
3614 ret = packet_mc_drop(sk, &mreq);
3615 return ret;
3616 }
3617
3618 case PACKET_RX_RING:
3619 case PACKET_TX_RING:
3620 {
3621 union tpacket_req_u req_u;
3622 int len;
3623
3624 switch (po->tp_version) {
3625 case TPACKET_V1:
3626 case TPACKET_V2:
3627 len = sizeof(req_u.req);
3628 break;
3629 case TPACKET_V3:
3630 default:
3631 len = sizeof(req_u.req3);
3632 break;
3633 }
3634 if (optlen < len)
3635 return -EINVAL;
3636 if (copy_from_user(&req_u.req, optval, len))
3637 return -EFAULT;
3638 return packet_set_ring(sk, &req_u, 0,
3639 optname == PACKET_TX_RING);
3640 }
3641 case PACKET_COPY_THRESH:
3642 {
3643 int val;
3644
3645 if (optlen != sizeof(val))
3646 return -EINVAL;
3647 if (copy_from_user(&val, optval, sizeof(val)))
3648 return -EFAULT;
3649
3650 pkt_sk(sk)->copy_thresh = val;
3651 return 0;
3652 }
3653 case PACKET_VERSION:
3654 {
3655 int val;
3656
3657 if (optlen != sizeof(val))
3658 return -EINVAL;
3659 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3660 return -EBUSY;
3661 if (copy_from_user(&val, optval, sizeof(val)))
3662 return -EFAULT;
3663 switch (val) {
3664 case TPACKET_V1:
3665 case TPACKET_V2:
3666 case TPACKET_V3:
3667 po->tp_version = val;
3668 return 0;
3669 default:
3670 return -EINVAL;
3671 }
3672 }
3673 case PACKET_RESERVE:
3674 {
3675 unsigned int val;
3676
3677 if (optlen != sizeof(val))
3678 return -EINVAL;
3679 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3680 return -EBUSY;
3681 if (copy_from_user(&val, optval, sizeof(val)))
3682 return -EFAULT;
3683 po->tp_reserve = val;
3684 return 0;
3685 }
3686 case PACKET_LOSS:
3687 {
3688 unsigned int val;
3689
3690 if (optlen != sizeof(val))
3691 return -EINVAL;
3692 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3693 return -EBUSY;
3694 if (copy_from_user(&val, optval, sizeof(val)))
3695 return -EFAULT;
3696 po->tp_loss = !!val;
3697 return 0;
3698 }
3699 case PACKET_AUXDATA:
3700 {
3701 int val;
3702
3703 if (optlen < sizeof(val))
3704 return -EINVAL;
3705 if (copy_from_user(&val, optval, sizeof(val)))
3706 return -EFAULT;
3707
3708 po->auxdata = !!val;
3709 return 0;
3710 }
3711 case PACKET_ORIGDEV:
3712 {
3713 int val;
3714
3715 if (optlen < sizeof(val))
3716 return -EINVAL;
3717 if (copy_from_user(&val, optval, sizeof(val)))
3718 return -EFAULT;
3719
3720 po->origdev = !!val;
3721 return 0;
3722 }
3723 case PACKET_VNET_HDR:
3724 {
3725 int val;
3726
3727 if (sock->type != SOCK_RAW)
3728 return -EINVAL;
3729 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3730 return -EBUSY;
3731 if (optlen < sizeof(val))
3732 return -EINVAL;
3733 if (copy_from_user(&val, optval, sizeof(val)))
3734 return -EFAULT;
3735
3736 po->has_vnet_hdr = !!val;
3737 return 0;
3738 }
3739 case PACKET_TIMESTAMP:
3740 {
3741 int val;
3742
3743 if (optlen != sizeof(val))
3744 return -EINVAL;
3745 if (copy_from_user(&val, optval, sizeof(val)))
3746 return -EFAULT;
3747
3748 po->tp_tstamp = val;
3749 return 0;
3750 }
3751 case PACKET_FANOUT:
3752 {
3753 int val;
3754
3755 if (optlen != sizeof(val))
3756 return -EINVAL;
3757 if (copy_from_user(&val, optval, sizeof(val)))
3758 return -EFAULT;
3759
3760 return fanout_add(sk, val & 0xffff, val >> 16);
3761 }
3762 case PACKET_FANOUT_DATA:
3763 {
3764 if (!po->fanout)
3765 return -EINVAL;
3766
3767 return fanout_set_data(po, optval, optlen);
3768 }
3769 case PACKET_TX_HAS_OFF:
3770 {
3771 unsigned int val;
3772
3773 if (optlen != sizeof(val))
3774 return -EINVAL;
3775 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3776 return -EBUSY;
3777 if (copy_from_user(&val, optval, sizeof(val)))
3778 return -EFAULT;
3779 po->tp_tx_has_off = !!val;
3780 return 0;
3781 }
3782 case PACKET_QDISC_BYPASS:
3783 {
3784 int val;
3785
3786 if (optlen != sizeof(val))
3787 return -EINVAL;
3788 if (copy_from_user(&val, optval, sizeof(val)))
3789 return -EFAULT;
3790
3791 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3792 return 0;
3793 }
3794 default:
3795 return -ENOPROTOOPT;
3796 }
3797}
3798
3799static int packet_getsockopt(struct socket *sock, int level, int optname,
3800 char __user *optval, int __user *optlen)
3801{
3802 int len;
3803 int val, lv = sizeof(val);
3804 struct sock *sk = sock->sk;
3805 struct packet_sock *po = pkt_sk(sk);
3806 void *data = &val;
3807 union tpacket_stats_u st;
3808 struct tpacket_rollover_stats rstats;
3809
3810 if (level != SOL_PACKET)
3811 return -ENOPROTOOPT;
3812
3813 if (get_user(len, optlen))
3814 return -EFAULT;
3815
3816 if (len < 0)
3817 return -EINVAL;
3818
3819 switch (optname) {
3820 case PACKET_STATISTICS:
3821 spin_lock_bh(&sk->sk_receive_queue.lock);
3822 memcpy(&st, &po->stats, sizeof(st));
3823 memset(&po->stats, 0, sizeof(po->stats));
3824 spin_unlock_bh(&sk->sk_receive_queue.lock);
3825
3826 if (po->tp_version == TPACKET_V3) {
3827 lv = sizeof(struct tpacket_stats_v3);
3828 st.stats3.tp_packets += st.stats3.tp_drops;
3829 data = &st.stats3;
3830 } else {
3831 lv = sizeof(struct tpacket_stats);
3832 st.stats1.tp_packets += st.stats1.tp_drops;
3833 data = &st.stats1;
3834 }
3835
3836 break;
3837 case PACKET_AUXDATA:
3838 val = po->auxdata;
3839 break;
3840 case PACKET_ORIGDEV:
3841 val = po->origdev;
3842 break;
3843 case PACKET_VNET_HDR:
3844 val = po->has_vnet_hdr;
3845 break;
3846 case PACKET_VERSION:
3847 val = po->tp_version;
3848 break;
3849 case PACKET_HDRLEN:
3850 if (len > sizeof(int))
3851 len = sizeof(int);
3852 if (copy_from_user(&val, optval, len))
3853 return -EFAULT;
3854 switch (val) {
3855 case TPACKET_V1:
3856 val = sizeof(struct tpacket_hdr);
3857 break;
3858 case TPACKET_V2:
3859 val = sizeof(struct tpacket2_hdr);
3860 break;
3861 case TPACKET_V3:
3862 val = sizeof(struct tpacket3_hdr);
3863 break;
3864 default:
3865 return -EINVAL;
3866 }
3867 break;
3868 case PACKET_RESERVE:
3869 val = po->tp_reserve;
3870 break;
3871 case PACKET_LOSS:
3872 val = po->tp_loss;
3873 break;
3874 case PACKET_TIMESTAMP:
3875 val = po->tp_tstamp;
3876 break;
3877 case PACKET_FANOUT:
3878 val = (po->fanout ?
3879 ((u32)po->fanout->id |
3880 ((u32)po->fanout->type << 16) |
3881 ((u32)po->fanout->flags << 24)) :
3882 0);
3883 break;
3884 case PACKET_ROLLOVER_STATS:
3885 if (!po->rollover)
3886 return -EINVAL;
3887 rstats.tp_all = atomic_long_read(&po->rollover->num);
3888 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
3889 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
3890 data = &rstats;
3891 lv = sizeof(rstats);
3892 break;
3893 case PACKET_TX_HAS_OFF:
3894 val = po->tp_tx_has_off;
3895 break;
3896 case PACKET_QDISC_BYPASS:
3897 val = packet_use_direct_xmit(po);
3898 break;
3899 default:
3900 return -ENOPROTOOPT;
3901 }
3902
3903 if (len > lv)
3904 len = lv;
3905 if (put_user(len, optlen))
3906 return -EFAULT;
3907 if (copy_to_user(optval, data, len))
3908 return -EFAULT;
3909 return 0;
3910}
3911
3912
3913static int packet_notifier(struct notifier_block *this,
3914 unsigned long msg, void *ptr)
3915{
3916 struct sock *sk;
3917 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3918 struct net *net = dev_net(dev);
3919
3920 rcu_read_lock();
3921 sk_for_each_rcu(sk, &net->packet.sklist) {
3922 struct packet_sock *po = pkt_sk(sk);
3923
3924 switch (msg) {
3925 case NETDEV_UNREGISTER:
3926 if (po->mclist)
3927 packet_dev_mclist_delete(dev, &po->mclist);
3928 /* fallthrough */
3929
3930 case NETDEV_DOWN:
3931 if (dev->ifindex == po->ifindex) {
3932 spin_lock(&po->bind_lock);
3933 if (po->running) {
3934 __unregister_prot_hook(sk, false);
3935 sk->sk_err = ENETDOWN;
3936 if (!sock_flag(sk, SOCK_DEAD))
3937 sk->sk_error_report(sk);
3938 }
3939 if (msg == NETDEV_UNREGISTER) {
3940 packet_cached_dev_reset(po);
3941 po->ifindex = -1;
3942 if (po->prot_hook.dev)
3943 dev_put(po->prot_hook.dev);
3944 po->prot_hook.dev = NULL;
3945 }
3946 spin_unlock(&po->bind_lock);
3947 }
3948 break;
3949 case NETDEV_UP:
3950 if (dev->ifindex == po->ifindex) {
3951 spin_lock(&po->bind_lock);
3952 if (po->num)
3953 register_prot_hook(sk);
3954 spin_unlock(&po->bind_lock);
3955 }
3956 break;
3957 }
3958 }
3959 rcu_read_unlock();
3960 return NOTIFY_DONE;
3961}
3962
3963
3964static int packet_ioctl(struct socket *sock, unsigned int cmd,
3965 unsigned long arg)
3966{
3967 struct sock *sk = sock->sk;
3968
3969 switch (cmd) {
3970 case SIOCOUTQ:
3971 {
3972 int amount = sk_wmem_alloc_get(sk);
3973
3974 return put_user(amount, (int __user *)arg);
3975 }
3976 case SIOCINQ:
3977 {
3978 struct sk_buff *skb;
3979 int amount = 0;
3980
3981 spin_lock_bh(&sk->sk_receive_queue.lock);
3982 skb = skb_peek(&sk->sk_receive_queue);
3983 if (skb)
3984 amount = skb->len;
3985 spin_unlock_bh(&sk->sk_receive_queue.lock);
3986 return put_user(amount, (int __user *)arg);
3987 }
3988 case SIOCGSTAMP:
3989 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3990 case SIOCGSTAMPNS:
3991 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3992
3993#ifdef CONFIG_INET
3994 case SIOCADDRT:
3995 case SIOCDELRT:
3996 case SIOCDARP:
3997 case SIOCGARP:
3998 case SIOCSARP:
3999 case SIOCGIFADDR:
4000 case SIOCSIFADDR:
4001 case SIOCGIFBRDADDR:
4002 case SIOCSIFBRDADDR:
4003 case SIOCGIFNETMASK:
4004 case SIOCSIFNETMASK:
4005 case SIOCGIFDSTADDR:
4006 case SIOCSIFDSTADDR:
4007 case SIOCSIFFLAGS:
4008 return inet_dgram_ops.ioctl(sock, cmd, arg);
4009#endif
4010
4011 default:
4012 return -ENOIOCTLCMD;
4013 }
4014 return 0;
4015}
4016
4017static unsigned int packet_poll(struct file *file, struct socket *sock,
4018 poll_table *wait)
4019{
4020 struct sock *sk = sock->sk;
4021 struct packet_sock *po = pkt_sk(sk);
4022 unsigned int mask = datagram_poll(file, sock, wait);
4023
4024 spin_lock_bh(&sk->sk_receive_queue.lock);
4025 if (po->rx_ring.pg_vec) {
4026 if (!packet_previous_rx_frame(po, &po->rx_ring,
4027 TP_STATUS_KERNEL))
4028 mask |= POLLIN | POLLRDNORM;
4029 }
4030 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
4031 po->pressure = 0;
4032 spin_unlock_bh(&sk->sk_receive_queue.lock);
4033 spin_lock_bh(&sk->sk_write_queue.lock);
4034 if (po->tx_ring.pg_vec) {
4035 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4036 mask |= POLLOUT | POLLWRNORM;
4037 }
4038 spin_unlock_bh(&sk->sk_write_queue.lock);
4039 return mask;
4040}
4041
4042
4043/* Dirty? Well, I still did not learn better way to account
4044 * for user mmaps.
4045 */
4046
4047static void packet_mm_open(struct vm_area_struct *vma)
4048{
4049 struct file *file = vma->vm_file;
4050 struct socket *sock = file->private_data;
4051 struct sock *sk = sock->sk;
4052
4053 if (sk)
4054 atomic_inc(&pkt_sk(sk)->mapped);
4055}
4056
4057static void packet_mm_close(struct vm_area_struct *vma)
4058{
4059 struct file *file = vma->vm_file;
4060 struct socket *sock = file->private_data;
4061 struct sock *sk = sock->sk;
4062
4063 if (sk)
4064 atomic_dec(&pkt_sk(sk)->mapped);
4065}
4066
4067static const struct vm_operations_struct packet_mmap_ops = {
4068 .open = packet_mm_open,
4069 .close = packet_mm_close,
4070};
4071
4072static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4073 unsigned int len)
4074{
4075 int i;
4076
4077 for (i = 0; i < len; i++) {
4078 if (likely(pg_vec[i].buffer)) {
4079 if (is_vmalloc_addr(pg_vec[i].buffer))
4080 vfree(pg_vec[i].buffer);
4081 else
4082 free_pages((unsigned long)pg_vec[i].buffer,
4083 order);
4084 pg_vec[i].buffer = NULL;
4085 }
4086 }
4087 kfree(pg_vec);
4088}
4089
4090static char *alloc_one_pg_vec_page(unsigned long order)
4091{
4092 char *buffer;
4093 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4094 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4095
4096 buffer = (char *) __get_free_pages(gfp_flags, order);
4097 if (buffer)
4098 return buffer;
4099
4100 /* __get_free_pages failed, fall back to vmalloc */
4101 buffer = vzalloc((1 << order) * PAGE_SIZE);
4102 if (buffer)
4103 return buffer;
4104
4105 /* vmalloc failed, lets dig into swap here */
4106 gfp_flags &= ~__GFP_NORETRY;
4107 buffer = (char *) __get_free_pages(gfp_flags, order);
4108 if (buffer)
4109 return buffer;
4110
4111 /* complete and utter failure */
4112 return NULL;
4113}
4114
4115static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4116{
4117 unsigned int block_nr = req->tp_block_nr;
4118 struct pgv *pg_vec;
4119 int i;
4120
4121 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
4122 if (unlikely(!pg_vec))
4123 goto out;
4124
4125 for (i = 0; i < block_nr; i++) {
4126 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4127 if (unlikely(!pg_vec[i].buffer))
4128 goto out_free_pgvec;
4129 }
4130
4131out:
4132 return pg_vec;
4133
4134out_free_pgvec:
4135 free_pg_vec(pg_vec, order, block_nr);
4136 pg_vec = NULL;
4137 goto out;
4138}
4139
4140static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4141 int closing, int tx_ring)
4142{
4143 struct pgv *pg_vec = NULL;
4144 struct packet_sock *po = pkt_sk(sk);
4145 int was_running, order = 0;
4146 struct packet_ring_buffer *rb;
4147 struct sk_buff_head *rb_queue;
4148 __be16 num;
4149 int err = -EINVAL;
4150 /* Added to avoid minimal code churn */
4151 struct tpacket_req *req = &req_u->req;
4152
4153 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
4154 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
4155 net_warn_ratelimited("Tx-ring is not supported.\n");
4156 goto out;
4157 }
4158
4159 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4160 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4161
4162 err = -EBUSY;
4163 if (!closing) {
4164 if (atomic_read(&po->mapped))
4165 goto out;
4166 if (packet_read_pending(rb))
4167 goto out;
4168 }
4169
4170 if (req->tp_block_nr) {
4171 /* Sanity tests and some calculations */
4172 err = -EBUSY;
4173 if (unlikely(rb->pg_vec))
4174 goto out;
4175
4176 switch (po->tp_version) {
4177 case TPACKET_V1:
4178 po->tp_hdrlen = TPACKET_HDRLEN;
4179 break;
4180 case TPACKET_V2:
4181 po->tp_hdrlen = TPACKET2_HDRLEN;
4182 break;
4183 case TPACKET_V3:
4184 po->tp_hdrlen = TPACKET3_HDRLEN;
4185 break;
4186 }
4187
4188 err = -EINVAL;
4189 if (unlikely((int)req->tp_block_size <= 0))
4190 goto out;
4191 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4192 goto out;
4193 if (po->tp_version >= TPACKET_V3 &&
4194 (int)(req->tp_block_size -
4195 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
4196 goto out;
4197 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
4198 po->tp_reserve))
4199 goto out;
4200 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4201 goto out;
4202
4203 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4204 if (unlikely(rb->frames_per_block == 0))
4205 goto out;
4206 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4207 req->tp_frame_nr))
4208 goto out;
4209
4210 err = -ENOMEM;
4211 order = get_order(req->tp_block_size);
4212 pg_vec = alloc_pg_vec(req, order);
4213 if (unlikely(!pg_vec))
4214 goto out;
4215 switch (po->tp_version) {
4216 case TPACKET_V3:
4217 /* Transmit path is not supported. We checked
4218 * it above but just being paranoid
4219 */
4220 if (!tx_ring)
4221 init_prb_bdqc(po, rb, pg_vec, req_u);
4222 break;
4223 default:
4224 break;
4225 }
4226 }
4227 /* Done */
4228 else {
4229 err = -EINVAL;
4230 if (unlikely(req->tp_frame_nr))
4231 goto out;
4232 }
4233
4234 lock_sock(sk);
4235
4236 /* Detach socket from network */
4237 spin_lock(&po->bind_lock);
4238 was_running = po->running;
4239 num = po->num;
4240 if (was_running) {
4241 po->num = 0;
4242 __unregister_prot_hook(sk, false);
4243 }
4244 spin_unlock(&po->bind_lock);
4245
4246 synchronize_net();
4247
4248 err = -EBUSY;
4249 mutex_lock(&po->pg_vec_lock);
4250 if (closing || atomic_read(&po->mapped) == 0) {
4251 err = 0;
4252 spin_lock_bh(&rb_queue->lock);
4253 swap(rb->pg_vec, pg_vec);
4254 rb->frame_max = (req->tp_frame_nr - 1);
4255 rb->head = 0;
4256 rb->frame_size = req->tp_frame_size;
4257 spin_unlock_bh(&rb_queue->lock);
4258
4259 swap(rb->pg_vec_order, order);
4260 swap(rb->pg_vec_len, req->tp_block_nr);
4261
4262 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4263 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4264 tpacket_rcv : packet_rcv;
4265 skb_queue_purge(rb_queue);
4266 if (atomic_read(&po->mapped))
4267 pr_err("packet_mmap: vma is busy: %d\n",
4268 atomic_read(&po->mapped));
4269 }
4270 mutex_unlock(&po->pg_vec_lock);
4271
4272 spin_lock(&po->bind_lock);
4273 if (was_running) {
4274 po->num = num;
4275 register_prot_hook(sk);
4276 }
4277 spin_unlock(&po->bind_lock);
4278 if (closing && (po->tp_version > TPACKET_V2)) {
4279 /* Because we don't support block-based V3 on tx-ring */
4280 if (!tx_ring)
4281 prb_shutdown_retire_blk_timer(po, rb_queue);
4282 }
4283 release_sock(sk);
4284
4285 if (pg_vec)
4286 free_pg_vec(pg_vec, order, req->tp_block_nr);
4287out:
4288 return err;
4289}
4290
4291static int packet_mmap(struct file *file, struct socket *sock,
4292 struct vm_area_struct *vma)
4293{
4294 struct sock *sk = sock->sk;
4295 struct packet_sock *po = pkt_sk(sk);
4296 unsigned long size, expected_size;
4297 struct packet_ring_buffer *rb;
4298 unsigned long start;
4299 int err = -EINVAL;
4300 int i;
4301
4302 if (vma->vm_pgoff)
4303 return -EINVAL;
4304
4305 mutex_lock(&po->pg_vec_lock);
4306
4307 expected_size = 0;
4308 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4309 if (rb->pg_vec) {
4310 expected_size += rb->pg_vec_len
4311 * rb->pg_vec_pages
4312 * PAGE_SIZE;
4313 }
4314 }
4315
4316 if (expected_size == 0)
4317 goto out;
4318
4319 size = vma->vm_end - vma->vm_start;
4320 if (size != expected_size)
4321 goto out;
4322
4323 start = vma->vm_start;
4324 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4325 if (rb->pg_vec == NULL)
4326 continue;
4327
4328 for (i = 0; i < rb->pg_vec_len; i++) {
4329 struct page *page;
4330 void *kaddr = rb->pg_vec[i].buffer;
4331 int pg_num;
4332
4333 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4334 page = pgv_to_page(kaddr);
4335 err = vm_insert_page(vma, start, page);
4336 if (unlikely(err))
4337 goto out;
4338 start += PAGE_SIZE;
4339 kaddr += PAGE_SIZE;
4340 }
4341 }
4342 }
4343
4344 atomic_inc(&po->mapped);
4345 vma->vm_ops = &packet_mmap_ops;
4346 err = 0;
4347
4348out:
4349 mutex_unlock(&po->pg_vec_lock);
4350 return err;
4351}
4352
4353static const struct proto_ops packet_ops_spkt = {
4354 .family = PF_PACKET,
4355 .owner = THIS_MODULE,
4356 .release = packet_release,
4357 .bind = packet_bind_spkt,
4358 .connect = sock_no_connect,
4359 .socketpair = sock_no_socketpair,
4360 .accept = sock_no_accept,
4361 .getname = packet_getname_spkt,
4362 .poll = datagram_poll,
4363 .ioctl = packet_ioctl,
4364 .listen = sock_no_listen,
4365 .shutdown = sock_no_shutdown,
4366 .setsockopt = sock_no_setsockopt,
4367 .getsockopt = sock_no_getsockopt,
4368 .sendmsg = packet_sendmsg_spkt,
4369 .recvmsg = packet_recvmsg,
4370 .mmap = sock_no_mmap,
4371 .sendpage = sock_no_sendpage,
4372};
4373
4374static const struct proto_ops packet_ops = {
4375 .family = PF_PACKET,
4376 .owner = THIS_MODULE,
4377 .release = packet_release,
4378 .bind = packet_bind,
4379 .connect = sock_no_connect,
4380 .socketpair = sock_no_socketpair,
4381 .accept = sock_no_accept,
4382 .getname = packet_getname,
4383 .poll = packet_poll,
4384 .ioctl = packet_ioctl,
4385 .listen = sock_no_listen,
4386 .shutdown = sock_no_shutdown,
4387 .setsockopt = packet_setsockopt,
4388 .getsockopt = packet_getsockopt,
4389 .sendmsg = packet_sendmsg,
4390 .recvmsg = packet_recvmsg,
4391 .mmap = packet_mmap,
4392 .sendpage = sock_no_sendpage,
4393};
4394
4395static const struct net_proto_family packet_family_ops = {
4396 .family = PF_PACKET,
4397 .create = packet_create,
4398 .owner = THIS_MODULE,
4399};
4400
4401static struct notifier_block packet_netdev_notifier = {
4402 .notifier_call = packet_notifier,
4403};
4404
4405#ifdef CONFIG_PROC_FS
4406
4407static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4408 __acquires(RCU)
4409{
4410 struct net *net = seq_file_net(seq);
4411
4412 rcu_read_lock();
4413 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4414}
4415
4416static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4417{
4418 struct net *net = seq_file_net(seq);
4419 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4420}
4421
4422static void packet_seq_stop(struct seq_file *seq, void *v)
4423 __releases(RCU)
4424{
4425 rcu_read_unlock();
4426}
4427
4428static int packet_seq_show(struct seq_file *seq, void *v)
4429{
4430 if (v == SEQ_START_TOKEN)
4431 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4432 else {
4433 struct sock *s = sk_entry(v);
4434 const struct packet_sock *po = pkt_sk(s);
4435
4436 seq_printf(seq,
4437 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4438 s,
4439 atomic_read(&s->sk_refcnt),
4440 s->sk_type,
4441 ntohs(po->num),
4442 po->ifindex,
4443 po->running,
4444 atomic_read(&s->sk_rmem_alloc),
4445 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4446 sock_i_ino(s));
4447 }
4448
4449 return 0;
4450}
4451
4452static const struct seq_operations packet_seq_ops = {
4453 .start = packet_seq_start,
4454 .next = packet_seq_next,
4455 .stop = packet_seq_stop,
4456 .show = packet_seq_show,
4457};
4458
4459static int packet_seq_open(struct inode *inode, struct file *file)
4460{
4461 return seq_open_net(inode, file, &packet_seq_ops,
4462 sizeof(struct seq_net_private));
4463}
4464
4465static const struct file_operations packet_seq_fops = {
4466 .owner = THIS_MODULE,
4467 .open = packet_seq_open,
4468 .read = seq_read,
4469 .llseek = seq_lseek,
4470 .release = seq_release_net,
4471};
4472
4473#endif
4474
4475static int __net_init packet_net_init(struct net *net)
4476{
4477 mutex_init(&net->packet.sklist_lock);
4478 INIT_HLIST_HEAD(&net->packet.sklist);
4479
4480 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4481 return -ENOMEM;
4482
4483 return 0;
4484}
4485
4486static void __net_exit packet_net_exit(struct net *net)
4487{
4488 remove_proc_entry("packet", net->proc_net);
4489}
4490
4491static struct pernet_operations packet_net_ops = {
4492 .init = packet_net_init,
4493 .exit = packet_net_exit,
4494};
4495
4496
4497static void __exit packet_exit(void)
4498{
4499 unregister_netdevice_notifier(&packet_netdev_notifier);
4500 unregister_pernet_subsys(&packet_net_ops);
4501 sock_unregister(PF_PACKET);
4502 proto_unregister(&packet_proto);
4503}
4504
4505static int __init packet_init(void)
4506{
4507 int rc = proto_register(&packet_proto, 0);
4508
4509 if (rc != 0)
4510 goto out;
4511
4512 sock_register(&packet_family_ops);
4513 register_pernet_subsys(&packet_net_ops);
4514 register_netdevice_notifier(&packet_netdev_notifier);
4515out:
4516 return rc;
4517}
4518
4519module_init(packet_init);
4520module_exit(packet_exit);
4521MODULE_LICENSE("GPL");
4522MODULE_ALIAS_NETPROTO(PF_PACKET);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * PACKET - implements raw packet sockets.
8 *
9 * Authors: Ross Biro
10 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Alan Cox, <gw4pts@gw4pts.ampr.org>
12 *
13 * Fixes:
14 * Alan Cox : verify_area() now used correctly
15 * Alan Cox : new skbuff lists, look ma no backlogs!
16 * Alan Cox : tidied skbuff lists.
17 * Alan Cox : Now uses generic datagram routines I
18 * added. Also fixed the peek/read crash
19 * from all old Linux datagram code.
20 * Alan Cox : Uses the improved datagram code.
21 * Alan Cox : Added NULL's for socket options.
22 * Alan Cox : Re-commented the code.
23 * Alan Cox : Use new kernel side addressing
24 * Rob Janssen : Correct MTU usage.
25 * Dave Platt : Counter leaks caused by incorrect
26 * interrupt locking and some slightly
27 * dubious gcc output. Can you read
28 * compiler: it said _VOLATILE_
29 * Richard Kooijman : Timestamp fixes.
30 * Alan Cox : New buffers. Use sk->mac.raw.
31 * Alan Cox : sendmsg/recvmsg support.
32 * Alan Cox : Protocol setting support
33 * Alexey Kuznetsov : Untied from IPv4 stack.
34 * Cyrus Durgin : Fixed kerneld for kmod.
35 * Michal Ostrowski : Module initialization cleanup.
36 * Ulises Alonso : Frame number limit removal and
37 * packet_set_ring memory leak.
38 * Eric Biederman : Allow for > 8 byte hardware addresses.
39 * The convention is that longer addresses
40 * will simply extend the hardware address
41 * byte arrays at the end of sockaddr_ll
42 * and packet_mreq.
43 * Johann Baudy : Added TX RING.
44 * Chetan Loke : Implemented TPACKET_V3 block abstraction
45 * layer.
46 * Copyright (C) 2011, <lokec@ccs.neu.edu>
47 */
48
49#include <linux/ethtool.h>
50#include <linux/types.h>
51#include <linux/mm.h>
52#include <linux/capability.h>
53#include <linux/fcntl.h>
54#include <linux/socket.h>
55#include <linux/in.h>
56#include <linux/inet.h>
57#include <linux/netdevice.h>
58#include <linux/if_packet.h>
59#include <linux/wireless.h>
60#include <linux/kernel.h>
61#include <linux/kmod.h>
62#include <linux/slab.h>
63#include <linux/vmalloc.h>
64#include <net/net_namespace.h>
65#include <net/ip.h>
66#include <net/protocol.h>
67#include <linux/skbuff.h>
68#include <net/sock.h>
69#include <linux/errno.h>
70#include <linux/timer.h>
71#include <linux/uaccess.h>
72#include <asm/ioctls.h>
73#include <asm/page.h>
74#include <asm/cacheflush.h>
75#include <asm/io.h>
76#include <linux/proc_fs.h>
77#include <linux/seq_file.h>
78#include <linux/poll.h>
79#include <linux/module.h>
80#include <linux/init.h>
81#include <linux/mutex.h>
82#include <linux/if_vlan.h>
83#include <linux/virtio_net.h>
84#include <linux/errqueue.h>
85#include <linux/net_tstamp.h>
86#include <linux/percpu.h>
87#ifdef CONFIG_INET
88#include <net/inet_common.h>
89#endif
90#include <linux/bpf.h>
91#include <net/compat.h>
92
93#include "internal.h"
94
95/*
96 Assumptions:
97 - If the device has no dev->header_ops->create, there is no LL header
98 visible above the device. In this case, its hard_header_len should be 0.
99 The device may prepend its own header internally. In this case, its
100 needed_headroom should be set to the space needed for it to add its
101 internal header.
102 For example, a WiFi driver pretending to be an Ethernet driver should
103 set its hard_header_len to be the Ethernet header length, and set its
104 needed_headroom to be (the real WiFi header length - the fake Ethernet
105 header length).
106 - packet socket receives packets with pulled ll header,
107 so that SOCK_RAW should push it back.
108
109On receive:
110-----------
111
112Incoming, dev_has_header(dev) == true
113 mac_header -> ll header
114 data -> data
115
116Outgoing, dev_has_header(dev) == true
117 mac_header -> ll header
118 data -> ll header
119
120Incoming, dev_has_header(dev) == false
121 mac_header -> data
122 However drivers often make it point to the ll header.
123 This is incorrect because the ll header should be invisible to us.
124 data -> data
125
126Outgoing, dev_has_header(dev) == false
127 mac_header -> data. ll header is invisible to us.
128 data -> data
129
130Resume
131 If dev_has_header(dev) == false we are unable to restore the ll header,
132 because it is invisible to us.
133
134
135On transmit:
136------------
137
138dev_has_header(dev) == true
139 mac_header -> ll header
140 data -> ll header
141
142dev_has_header(dev) == false (ll header is invisible to us)
143 mac_header -> data
144 data -> data
145
146 We should set network_header on output to the correct position,
147 packet classifier depends on it.
148 */
149
150/* Private packet socket structures. */
151
152/* identical to struct packet_mreq except it has
153 * a longer address field.
154 */
155struct packet_mreq_max {
156 int mr_ifindex;
157 unsigned short mr_type;
158 unsigned short mr_alen;
159 unsigned char mr_address[MAX_ADDR_LEN];
160};
161
162union tpacket_uhdr {
163 struct tpacket_hdr *h1;
164 struct tpacket2_hdr *h2;
165 struct tpacket3_hdr *h3;
166 void *raw;
167};
168
169static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
170 int closing, int tx_ring);
171
172#define V3_ALIGNMENT (8)
173
174#define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
175
176#define BLK_PLUS_PRIV(sz_of_priv) \
177 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
178
179#define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
180#define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
181#define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
182#define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
183#define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
184#define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
185
186struct packet_sock;
187static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
188 struct packet_type *pt, struct net_device *orig_dev);
189
190static void *packet_previous_frame(struct packet_sock *po,
191 struct packet_ring_buffer *rb,
192 int status);
193static void packet_increment_head(struct packet_ring_buffer *buff);
194static int prb_curr_blk_in_use(struct tpacket_block_desc *);
195static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
196 struct packet_sock *);
197static void prb_retire_current_block(struct tpacket_kbdq_core *,
198 struct packet_sock *, unsigned int status);
199static int prb_queue_frozen(struct tpacket_kbdq_core *);
200static void prb_open_block(struct tpacket_kbdq_core *,
201 struct tpacket_block_desc *);
202static void prb_retire_rx_blk_timer_expired(struct timer_list *);
203static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
204static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
205static void prb_clear_rxhash(struct tpacket_kbdq_core *,
206 struct tpacket3_hdr *);
207static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
208 struct tpacket3_hdr *);
209static void packet_flush_mclist(struct sock *sk);
210static u16 packet_pick_tx_queue(struct sk_buff *skb);
211
212struct packet_skb_cb {
213 union {
214 struct sockaddr_pkt pkt;
215 union {
216 /* Trick: alias skb original length with
217 * ll.sll_family and ll.protocol in order
218 * to save room.
219 */
220 unsigned int origlen;
221 struct sockaddr_ll ll;
222 };
223 } sa;
224};
225
226#define vio_le() virtio_legacy_is_little_endian()
227
228#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
229
230#define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
231#define GET_PBLOCK_DESC(x, bid) \
232 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
233#define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
234 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
235#define GET_NEXT_PRB_BLK_NUM(x) \
236 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
237 ((x)->kactive_blk_num+1) : 0)
238
239static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
240static void __fanout_link(struct sock *sk, struct packet_sock *po);
241
242static int packet_direct_xmit(struct sk_buff *skb)
243{
244 return dev_direct_xmit(skb, packet_pick_tx_queue(skb));
245}
246
247static struct net_device *packet_cached_dev_get(struct packet_sock *po)
248{
249 struct net_device *dev;
250
251 rcu_read_lock();
252 dev = rcu_dereference(po->cached_dev);
253 if (likely(dev))
254 dev_hold(dev);
255 rcu_read_unlock();
256
257 return dev;
258}
259
260static void packet_cached_dev_assign(struct packet_sock *po,
261 struct net_device *dev)
262{
263 rcu_assign_pointer(po->cached_dev, dev);
264}
265
266static void packet_cached_dev_reset(struct packet_sock *po)
267{
268 RCU_INIT_POINTER(po->cached_dev, NULL);
269}
270
271static bool packet_use_direct_xmit(const struct packet_sock *po)
272{
273 return po->xmit == packet_direct_xmit;
274}
275
276static u16 packet_pick_tx_queue(struct sk_buff *skb)
277{
278 struct net_device *dev = skb->dev;
279 const struct net_device_ops *ops = dev->netdev_ops;
280 int cpu = raw_smp_processor_id();
281 u16 queue_index;
282
283#ifdef CONFIG_XPS
284 skb->sender_cpu = cpu + 1;
285#endif
286 skb_record_rx_queue(skb, cpu % dev->real_num_tx_queues);
287 if (ops->ndo_select_queue) {
288 queue_index = ops->ndo_select_queue(dev, skb, NULL);
289 queue_index = netdev_cap_txqueue(dev, queue_index);
290 } else {
291 queue_index = netdev_pick_tx(dev, skb, NULL);
292 }
293
294 return queue_index;
295}
296
297/* __register_prot_hook must be invoked through register_prot_hook
298 * or from a context in which asynchronous accesses to the packet
299 * socket is not possible (packet_create()).
300 */
301static void __register_prot_hook(struct sock *sk)
302{
303 struct packet_sock *po = pkt_sk(sk);
304
305 if (!po->running) {
306 if (po->fanout)
307 __fanout_link(sk, po);
308 else
309 dev_add_pack(&po->prot_hook);
310
311 sock_hold(sk);
312 po->running = 1;
313 }
314}
315
316static void register_prot_hook(struct sock *sk)
317{
318 lockdep_assert_held_once(&pkt_sk(sk)->bind_lock);
319 __register_prot_hook(sk);
320}
321
322/* If the sync parameter is true, we will temporarily drop
323 * the po->bind_lock and do a synchronize_net to make sure no
324 * asynchronous packet processing paths still refer to the elements
325 * of po->prot_hook. If the sync parameter is false, it is the
326 * callers responsibility to take care of this.
327 */
328static void __unregister_prot_hook(struct sock *sk, bool sync)
329{
330 struct packet_sock *po = pkt_sk(sk);
331
332 lockdep_assert_held_once(&po->bind_lock);
333
334 po->running = 0;
335
336 if (po->fanout)
337 __fanout_unlink(sk, po);
338 else
339 __dev_remove_pack(&po->prot_hook);
340
341 __sock_put(sk);
342
343 if (sync) {
344 spin_unlock(&po->bind_lock);
345 synchronize_net();
346 spin_lock(&po->bind_lock);
347 }
348}
349
350static void unregister_prot_hook(struct sock *sk, bool sync)
351{
352 struct packet_sock *po = pkt_sk(sk);
353
354 if (po->running)
355 __unregister_prot_hook(sk, sync);
356}
357
358static inline struct page * __pure pgv_to_page(void *addr)
359{
360 if (is_vmalloc_addr(addr))
361 return vmalloc_to_page(addr);
362 return virt_to_page(addr);
363}
364
365static void __packet_set_status(struct packet_sock *po, void *frame, int status)
366{
367 union tpacket_uhdr h;
368
369 h.raw = frame;
370 switch (po->tp_version) {
371 case TPACKET_V1:
372 h.h1->tp_status = status;
373 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
374 break;
375 case TPACKET_V2:
376 h.h2->tp_status = status;
377 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
378 break;
379 case TPACKET_V3:
380 h.h3->tp_status = status;
381 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
382 break;
383 default:
384 WARN(1, "TPACKET version not supported.\n");
385 BUG();
386 }
387
388 smp_wmb();
389}
390
391static int __packet_get_status(const struct packet_sock *po, void *frame)
392{
393 union tpacket_uhdr h;
394
395 smp_rmb();
396
397 h.raw = frame;
398 switch (po->tp_version) {
399 case TPACKET_V1:
400 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
401 return h.h1->tp_status;
402 case TPACKET_V2:
403 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
404 return h.h2->tp_status;
405 case TPACKET_V3:
406 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
407 return h.h3->tp_status;
408 default:
409 WARN(1, "TPACKET version not supported.\n");
410 BUG();
411 return 0;
412 }
413}
414
415static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec64 *ts,
416 unsigned int flags)
417{
418 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
419
420 if (shhwtstamps &&
421 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
422 ktime_to_timespec64_cond(shhwtstamps->hwtstamp, ts))
423 return TP_STATUS_TS_RAW_HARDWARE;
424
425 if ((flags & SOF_TIMESTAMPING_SOFTWARE) &&
426 ktime_to_timespec64_cond(skb->tstamp, ts))
427 return TP_STATUS_TS_SOFTWARE;
428
429 return 0;
430}
431
432static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
433 struct sk_buff *skb)
434{
435 union tpacket_uhdr h;
436 struct timespec64 ts;
437 __u32 ts_status;
438
439 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
440 return 0;
441
442 h.raw = frame;
443 /*
444 * versions 1 through 3 overflow the timestamps in y2106, since they
445 * all store the seconds in a 32-bit unsigned integer.
446 * If we create a version 4, that should have a 64-bit timestamp,
447 * either 64-bit seconds + 32-bit nanoseconds, or just 64-bit
448 * nanoseconds.
449 */
450 switch (po->tp_version) {
451 case TPACKET_V1:
452 h.h1->tp_sec = ts.tv_sec;
453 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
454 break;
455 case TPACKET_V2:
456 h.h2->tp_sec = ts.tv_sec;
457 h.h2->tp_nsec = ts.tv_nsec;
458 break;
459 case TPACKET_V3:
460 h.h3->tp_sec = ts.tv_sec;
461 h.h3->tp_nsec = ts.tv_nsec;
462 break;
463 default:
464 WARN(1, "TPACKET version not supported.\n");
465 BUG();
466 }
467
468 /* one flush is safe, as both fields always lie on the same cacheline */
469 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
470 smp_wmb();
471
472 return ts_status;
473}
474
475static void *packet_lookup_frame(const struct packet_sock *po,
476 const struct packet_ring_buffer *rb,
477 unsigned int position,
478 int status)
479{
480 unsigned int pg_vec_pos, frame_offset;
481 union tpacket_uhdr h;
482
483 pg_vec_pos = position / rb->frames_per_block;
484 frame_offset = position % rb->frames_per_block;
485
486 h.raw = rb->pg_vec[pg_vec_pos].buffer +
487 (frame_offset * rb->frame_size);
488
489 if (status != __packet_get_status(po, h.raw))
490 return NULL;
491
492 return h.raw;
493}
494
495static void *packet_current_frame(struct packet_sock *po,
496 struct packet_ring_buffer *rb,
497 int status)
498{
499 return packet_lookup_frame(po, rb, rb->head, status);
500}
501
502static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
503{
504 del_timer_sync(&pkc->retire_blk_timer);
505}
506
507static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
508 struct sk_buff_head *rb_queue)
509{
510 struct tpacket_kbdq_core *pkc;
511
512 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
513
514 spin_lock_bh(&rb_queue->lock);
515 pkc->delete_blk_timer = 1;
516 spin_unlock_bh(&rb_queue->lock);
517
518 prb_del_retire_blk_timer(pkc);
519}
520
521static void prb_setup_retire_blk_timer(struct packet_sock *po)
522{
523 struct tpacket_kbdq_core *pkc;
524
525 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
526 timer_setup(&pkc->retire_blk_timer, prb_retire_rx_blk_timer_expired,
527 0);
528 pkc->retire_blk_timer.expires = jiffies;
529}
530
531static int prb_calc_retire_blk_tmo(struct packet_sock *po,
532 int blk_size_in_bytes)
533{
534 struct net_device *dev;
535 unsigned int mbits, div;
536 struct ethtool_link_ksettings ecmd;
537 int err;
538
539 rtnl_lock();
540 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
541 if (unlikely(!dev)) {
542 rtnl_unlock();
543 return DEFAULT_PRB_RETIRE_TOV;
544 }
545 err = __ethtool_get_link_ksettings(dev, &ecmd);
546 rtnl_unlock();
547 if (err)
548 return DEFAULT_PRB_RETIRE_TOV;
549
550 /* If the link speed is so slow you don't really
551 * need to worry about perf anyways
552 */
553 if (ecmd.base.speed < SPEED_1000 ||
554 ecmd.base.speed == SPEED_UNKNOWN)
555 return DEFAULT_PRB_RETIRE_TOV;
556
557 div = ecmd.base.speed / 1000;
558 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
559
560 if (div)
561 mbits /= div;
562
563 if (div)
564 return mbits + 1;
565 return mbits;
566}
567
568static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
569 union tpacket_req_u *req_u)
570{
571 p1->feature_req_word = req_u->req3.tp_feature_req_word;
572}
573
574static void init_prb_bdqc(struct packet_sock *po,
575 struct packet_ring_buffer *rb,
576 struct pgv *pg_vec,
577 union tpacket_req_u *req_u)
578{
579 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
580 struct tpacket_block_desc *pbd;
581
582 memset(p1, 0x0, sizeof(*p1));
583
584 p1->knxt_seq_num = 1;
585 p1->pkbdq = pg_vec;
586 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
587 p1->pkblk_start = pg_vec[0].buffer;
588 p1->kblk_size = req_u->req3.tp_block_size;
589 p1->knum_blocks = req_u->req3.tp_block_nr;
590 p1->hdrlen = po->tp_hdrlen;
591 p1->version = po->tp_version;
592 p1->last_kactive_blk_num = 0;
593 po->stats.stats3.tp_freeze_q_cnt = 0;
594 if (req_u->req3.tp_retire_blk_tov)
595 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
596 else
597 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
598 req_u->req3.tp_block_size);
599 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
600 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
601 rwlock_init(&p1->blk_fill_in_prog_lock);
602
603 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
604 prb_init_ft_ops(p1, req_u);
605 prb_setup_retire_blk_timer(po);
606 prb_open_block(p1, pbd);
607}
608
609/* Do NOT update the last_blk_num first.
610 * Assumes sk_buff_head lock is held.
611 */
612static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
613{
614 mod_timer(&pkc->retire_blk_timer,
615 jiffies + pkc->tov_in_jiffies);
616 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
617}
618
619/*
620 * Timer logic:
621 * 1) We refresh the timer only when we open a block.
622 * By doing this we don't waste cycles refreshing the timer
623 * on packet-by-packet basis.
624 *
625 * With a 1MB block-size, on a 1Gbps line, it will take
626 * i) ~8 ms to fill a block + ii) memcpy etc.
627 * In this cut we are not accounting for the memcpy time.
628 *
629 * So, if the user sets the 'tmo' to 10ms then the timer
630 * will never fire while the block is still getting filled
631 * (which is what we want). However, the user could choose
632 * to close a block early and that's fine.
633 *
634 * But when the timer does fire, we check whether or not to refresh it.
635 * Since the tmo granularity is in msecs, it is not too expensive
636 * to refresh the timer, lets say every '8' msecs.
637 * Either the user can set the 'tmo' or we can derive it based on
638 * a) line-speed and b) block-size.
639 * prb_calc_retire_blk_tmo() calculates the tmo.
640 *
641 */
642static void prb_retire_rx_blk_timer_expired(struct timer_list *t)
643{
644 struct packet_sock *po =
645 from_timer(po, t, rx_ring.prb_bdqc.retire_blk_timer);
646 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
647 unsigned int frozen;
648 struct tpacket_block_desc *pbd;
649
650 spin_lock(&po->sk.sk_receive_queue.lock);
651
652 frozen = prb_queue_frozen(pkc);
653 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
654
655 if (unlikely(pkc->delete_blk_timer))
656 goto out;
657
658 /* We only need to plug the race when the block is partially filled.
659 * tpacket_rcv:
660 * lock(); increment BLOCK_NUM_PKTS; unlock()
661 * copy_bits() is in progress ...
662 * timer fires on other cpu:
663 * we can't retire the current block because copy_bits
664 * is in progress.
665 *
666 */
667 if (BLOCK_NUM_PKTS(pbd)) {
668 /* Waiting for skb_copy_bits to finish... */
669 write_lock(&pkc->blk_fill_in_prog_lock);
670 write_unlock(&pkc->blk_fill_in_prog_lock);
671 }
672
673 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
674 if (!frozen) {
675 if (!BLOCK_NUM_PKTS(pbd)) {
676 /* An empty block. Just refresh the timer. */
677 goto refresh_timer;
678 }
679 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
680 if (!prb_dispatch_next_block(pkc, po))
681 goto refresh_timer;
682 else
683 goto out;
684 } else {
685 /* Case 1. Queue was frozen because user-space was
686 * lagging behind.
687 */
688 if (prb_curr_blk_in_use(pbd)) {
689 /*
690 * Ok, user-space is still behind.
691 * So just refresh the timer.
692 */
693 goto refresh_timer;
694 } else {
695 /* Case 2. queue was frozen,user-space caught up,
696 * now the link went idle && the timer fired.
697 * We don't have a block to close.So we open this
698 * block and restart the timer.
699 * opening a block thaws the queue,restarts timer
700 * Thawing/timer-refresh is a side effect.
701 */
702 prb_open_block(pkc, pbd);
703 goto out;
704 }
705 }
706 }
707
708refresh_timer:
709 _prb_refresh_rx_retire_blk_timer(pkc);
710
711out:
712 spin_unlock(&po->sk.sk_receive_queue.lock);
713}
714
715static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
716 struct tpacket_block_desc *pbd1, __u32 status)
717{
718 /* Flush everything minus the block header */
719
720#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
721 u8 *start, *end;
722
723 start = (u8 *)pbd1;
724
725 /* Skip the block header(we know header WILL fit in 4K) */
726 start += PAGE_SIZE;
727
728 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
729 for (; start < end; start += PAGE_SIZE)
730 flush_dcache_page(pgv_to_page(start));
731
732 smp_wmb();
733#endif
734
735 /* Now update the block status. */
736
737 BLOCK_STATUS(pbd1) = status;
738
739 /* Flush the block header */
740
741#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
742 start = (u8 *)pbd1;
743 flush_dcache_page(pgv_to_page(start));
744
745 smp_wmb();
746#endif
747}
748
749/*
750 * Side effect:
751 *
752 * 1) flush the block
753 * 2) Increment active_blk_num
754 *
755 * Note:We DONT refresh the timer on purpose.
756 * Because almost always the next block will be opened.
757 */
758static void prb_close_block(struct tpacket_kbdq_core *pkc1,
759 struct tpacket_block_desc *pbd1,
760 struct packet_sock *po, unsigned int stat)
761{
762 __u32 status = TP_STATUS_USER | stat;
763
764 struct tpacket3_hdr *last_pkt;
765 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
766 struct sock *sk = &po->sk;
767
768 if (atomic_read(&po->tp_drops))
769 status |= TP_STATUS_LOSING;
770
771 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
772 last_pkt->tp_next_offset = 0;
773
774 /* Get the ts of the last pkt */
775 if (BLOCK_NUM_PKTS(pbd1)) {
776 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
777 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
778 } else {
779 /* Ok, we tmo'd - so get the current time.
780 *
781 * It shouldn't really happen as we don't close empty
782 * blocks. See prb_retire_rx_blk_timer_expired().
783 */
784 struct timespec64 ts;
785 ktime_get_real_ts64(&ts);
786 h1->ts_last_pkt.ts_sec = ts.tv_sec;
787 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
788 }
789
790 smp_wmb();
791
792 /* Flush the block */
793 prb_flush_block(pkc1, pbd1, status);
794
795 sk->sk_data_ready(sk);
796
797 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
798}
799
800static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
801{
802 pkc->reset_pending_on_curr_blk = 0;
803}
804
805/*
806 * Side effect of opening a block:
807 *
808 * 1) prb_queue is thawed.
809 * 2) retire_blk_timer is refreshed.
810 *
811 */
812static void prb_open_block(struct tpacket_kbdq_core *pkc1,
813 struct tpacket_block_desc *pbd1)
814{
815 struct timespec64 ts;
816 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
817
818 smp_rmb();
819
820 /* We could have just memset this but we will lose the
821 * flexibility of making the priv area sticky
822 */
823
824 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
825 BLOCK_NUM_PKTS(pbd1) = 0;
826 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
827
828 ktime_get_real_ts64(&ts);
829
830 h1->ts_first_pkt.ts_sec = ts.tv_sec;
831 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
832
833 pkc1->pkblk_start = (char *)pbd1;
834 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
835
836 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
837 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
838
839 pbd1->version = pkc1->version;
840 pkc1->prev = pkc1->nxt_offset;
841 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
842
843 prb_thaw_queue(pkc1);
844 _prb_refresh_rx_retire_blk_timer(pkc1);
845
846 smp_wmb();
847}
848
849/*
850 * Queue freeze logic:
851 * 1) Assume tp_block_nr = 8 blocks.
852 * 2) At time 't0', user opens Rx ring.
853 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
854 * 4) user-space is either sleeping or processing block '0'.
855 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
856 * it will close block-7,loop around and try to fill block '0'.
857 * call-flow:
858 * __packet_lookup_frame_in_block
859 * prb_retire_current_block()
860 * prb_dispatch_next_block()
861 * |->(BLOCK_STATUS == USER) evaluates to true
862 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
863 * 6) Now there are two cases:
864 * 6.1) Link goes idle right after the queue is frozen.
865 * But remember, the last open_block() refreshed the timer.
866 * When this timer expires,it will refresh itself so that we can
867 * re-open block-0 in near future.
868 * 6.2) Link is busy and keeps on receiving packets. This is a simple
869 * case and __packet_lookup_frame_in_block will check if block-0
870 * is free and can now be re-used.
871 */
872static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
873 struct packet_sock *po)
874{
875 pkc->reset_pending_on_curr_blk = 1;
876 po->stats.stats3.tp_freeze_q_cnt++;
877}
878
879#define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
880
881/*
882 * If the next block is free then we will dispatch it
883 * and return a good offset.
884 * Else, we will freeze the queue.
885 * So, caller must check the return value.
886 */
887static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
888 struct packet_sock *po)
889{
890 struct tpacket_block_desc *pbd;
891
892 smp_rmb();
893
894 /* 1. Get current block num */
895 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
896
897 /* 2. If this block is currently in_use then freeze the queue */
898 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
899 prb_freeze_queue(pkc, po);
900 return NULL;
901 }
902
903 /*
904 * 3.
905 * open this block and return the offset where the first packet
906 * needs to get stored.
907 */
908 prb_open_block(pkc, pbd);
909 return (void *)pkc->nxt_offset;
910}
911
912static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
913 struct packet_sock *po, unsigned int status)
914{
915 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
916
917 /* retire/close the current block */
918 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
919 /*
920 * Plug the case where copy_bits() is in progress on
921 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
922 * have space to copy the pkt in the current block and
923 * called prb_retire_current_block()
924 *
925 * We don't need to worry about the TMO case because
926 * the timer-handler already handled this case.
927 */
928 if (!(status & TP_STATUS_BLK_TMO)) {
929 /* Waiting for skb_copy_bits to finish... */
930 write_lock(&pkc->blk_fill_in_prog_lock);
931 write_unlock(&pkc->blk_fill_in_prog_lock);
932 }
933 prb_close_block(pkc, pbd, po, status);
934 return;
935 }
936}
937
938static int prb_curr_blk_in_use(struct tpacket_block_desc *pbd)
939{
940 return TP_STATUS_USER & BLOCK_STATUS(pbd);
941}
942
943static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
944{
945 return pkc->reset_pending_on_curr_blk;
946}
947
948static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
949 __releases(&pkc->blk_fill_in_prog_lock)
950{
951 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
952
953 read_unlock(&pkc->blk_fill_in_prog_lock);
954}
955
956static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
957 struct tpacket3_hdr *ppd)
958{
959 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
960}
961
962static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
963 struct tpacket3_hdr *ppd)
964{
965 ppd->hv1.tp_rxhash = 0;
966}
967
968static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
969 struct tpacket3_hdr *ppd)
970{
971 if (skb_vlan_tag_present(pkc->skb)) {
972 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
973 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
974 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
975 } else {
976 ppd->hv1.tp_vlan_tci = 0;
977 ppd->hv1.tp_vlan_tpid = 0;
978 ppd->tp_status = TP_STATUS_AVAILABLE;
979 }
980}
981
982static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
983 struct tpacket3_hdr *ppd)
984{
985 ppd->hv1.tp_padding = 0;
986 prb_fill_vlan_info(pkc, ppd);
987
988 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
989 prb_fill_rxhash(pkc, ppd);
990 else
991 prb_clear_rxhash(pkc, ppd);
992}
993
994static void prb_fill_curr_block(char *curr,
995 struct tpacket_kbdq_core *pkc,
996 struct tpacket_block_desc *pbd,
997 unsigned int len)
998 __acquires(&pkc->blk_fill_in_prog_lock)
999{
1000 struct tpacket3_hdr *ppd;
1001
1002 ppd = (struct tpacket3_hdr *)curr;
1003 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1004 pkc->prev = curr;
1005 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1006 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1007 BLOCK_NUM_PKTS(pbd) += 1;
1008 read_lock(&pkc->blk_fill_in_prog_lock);
1009 prb_run_all_ft_ops(pkc, ppd);
1010}
1011
1012/* Assumes caller has the sk->rx_queue.lock */
1013static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1014 struct sk_buff *skb,
1015 unsigned int len
1016 )
1017{
1018 struct tpacket_kbdq_core *pkc;
1019 struct tpacket_block_desc *pbd;
1020 char *curr, *end;
1021
1022 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1023 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1024
1025 /* Queue is frozen when user space is lagging behind */
1026 if (prb_queue_frozen(pkc)) {
1027 /*
1028 * Check if that last block which caused the queue to freeze,
1029 * is still in_use by user-space.
1030 */
1031 if (prb_curr_blk_in_use(pbd)) {
1032 /* Can't record this packet */
1033 return NULL;
1034 } else {
1035 /*
1036 * Ok, the block was released by user-space.
1037 * Now let's open that block.
1038 * opening a block also thaws the queue.
1039 * Thawing is a side effect.
1040 */
1041 prb_open_block(pkc, pbd);
1042 }
1043 }
1044
1045 smp_mb();
1046 curr = pkc->nxt_offset;
1047 pkc->skb = skb;
1048 end = (char *)pbd + pkc->kblk_size;
1049
1050 /* first try the current block */
1051 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1052 prb_fill_curr_block(curr, pkc, pbd, len);
1053 return (void *)curr;
1054 }
1055
1056 /* Ok, close the current block */
1057 prb_retire_current_block(pkc, po, 0);
1058
1059 /* Now, try to dispatch the next block */
1060 curr = (char *)prb_dispatch_next_block(pkc, po);
1061 if (curr) {
1062 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1063 prb_fill_curr_block(curr, pkc, pbd, len);
1064 return (void *)curr;
1065 }
1066
1067 /*
1068 * No free blocks are available.user_space hasn't caught up yet.
1069 * Queue was just frozen and now this packet will get dropped.
1070 */
1071 return NULL;
1072}
1073
1074static void *packet_current_rx_frame(struct packet_sock *po,
1075 struct sk_buff *skb,
1076 int status, unsigned int len)
1077{
1078 char *curr = NULL;
1079 switch (po->tp_version) {
1080 case TPACKET_V1:
1081 case TPACKET_V2:
1082 curr = packet_lookup_frame(po, &po->rx_ring,
1083 po->rx_ring.head, status);
1084 return curr;
1085 case TPACKET_V3:
1086 return __packet_lookup_frame_in_block(po, skb, len);
1087 default:
1088 WARN(1, "TPACKET version not supported\n");
1089 BUG();
1090 return NULL;
1091 }
1092}
1093
1094static void *prb_lookup_block(const struct packet_sock *po,
1095 const struct packet_ring_buffer *rb,
1096 unsigned int idx,
1097 int status)
1098{
1099 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1100 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1101
1102 if (status != BLOCK_STATUS(pbd))
1103 return NULL;
1104 return pbd;
1105}
1106
1107static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1108{
1109 unsigned int prev;
1110 if (rb->prb_bdqc.kactive_blk_num)
1111 prev = rb->prb_bdqc.kactive_blk_num-1;
1112 else
1113 prev = rb->prb_bdqc.knum_blocks-1;
1114 return prev;
1115}
1116
1117/* Assumes caller has held the rx_queue.lock */
1118static void *__prb_previous_block(struct packet_sock *po,
1119 struct packet_ring_buffer *rb,
1120 int status)
1121{
1122 unsigned int previous = prb_previous_blk_num(rb);
1123 return prb_lookup_block(po, rb, previous, status);
1124}
1125
1126static void *packet_previous_rx_frame(struct packet_sock *po,
1127 struct packet_ring_buffer *rb,
1128 int status)
1129{
1130 if (po->tp_version <= TPACKET_V2)
1131 return packet_previous_frame(po, rb, status);
1132
1133 return __prb_previous_block(po, rb, status);
1134}
1135
1136static void packet_increment_rx_head(struct packet_sock *po,
1137 struct packet_ring_buffer *rb)
1138{
1139 switch (po->tp_version) {
1140 case TPACKET_V1:
1141 case TPACKET_V2:
1142 return packet_increment_head(rb);
1143 case TPACKET_V3:
1144 default:
1145 WARN(1, "TPACKET version not supported.\n");
1146 BUG();
1147 return;
1148 }
1149}
1150
1151static void *packet_previous_frame(struct packet_sock *po,
1152 struct packet_ring_buffer *rb,
1153 int status)
1154{
1155 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1156 return packet_lookup_frame(po, rb, previous, status);
1157}
1158
1159static void packet_increment_head(struct packet_ring_buffer *buff)
1160{
1161 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1162}
1163
1164static void packet_inc_pending(struct packet_ring_buffer *rb)
1165{
1166 this_cpu_inc(*rb->pending_refcnt);
1167}
1168
1169static void packet_dec_pending(struct packet_ring_buffer *rb)
1170{
1171 this_cpu_dec(*rb->pending_refcnt);
1172}
1173
1174static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1175{
1176 unsigned int refcnt = 0;
1177 int cpu;
1178
1179 /* We don't use pending refcount in rx_ring. */
1180 if (rb->pending_refcnt == NULL)
1181 return 0;
1182
1183 for_each_possible_cpu(cpu)
1184 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1185
1186 return refcnt;
1187}
1188
1189static int packet_alloc_pending(struct packet_sock *po)
1190{
1191 po->rx_ring.pending_refcnt = NULL;
1192
1193 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1194 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1195 return -ENOBUFS;
1196
1197 return 0;
1198}
1199
1200static void packet_free_pending(struct packet_sock *po)
1201{
1202 free_percpu(po->tx_ring.pending_refcnt);
1203}
1204
1205#define ROOM_POW_OFF 2
1206#define ROOM_NONE 0x0
1207#define ROOM_LOW 0x1
1208#define ROOM_NORMAL 0x2
1209
1210static bool __tpacket_has_room(const struct packet_sock *po, int pow_off)
1211{
1212 int idx, len;
1213
1214 len = READ_ONCE(po->rx_ring.frame_max) + 1;
1215 idx = READ_ONCE(po->rx_ring.head);
1216 if (pow_off)
1217 idx += len >> pow_off;
1218 if (idx >= len)
1219 idx -= len;
1220 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1221}
1222
1223static bool __tpacket_v3_has_room(const struct packet_sock *po, int pow_off)
1224{
1225 int idx, len;
1226
1227 len = READ_ONCE(po->rx_ring.prb_bdqc.knum_blocks);
1228 idx = READ_ONCE(po->rx_ring.prb_bdqc.kactive_blk_num);
1229 if (pow_off)
1230 idx += len >> pow_off;
1231 if (idx >= len)
1232 idx -= len;
1233 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1234}
1235
1236static int __packet_rcv_has_room(const struct packet_sock *po,
1237 const struct sk_buff *skb)
1238{
1239 const struct sock *sk = &po->sk;
1240 int ret = ROOM_NONE;
1241
1242 if (po->prot_hook.func != tpacket_rcv) {
1243 int rcvbuf = READ_ONCE(sk->sk_rcvbuf);
1244 int avail = rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1245 - (skb ? skb->truesize : 0);
1246
1247 if (avail > (rcvbuf >> ROOM_POW_OFF))
1248 return ROOM_NORMAL;
1249 else if (avail > 0)
1250 return ROOM_LOW;
1251 else
1252 return ROOM_NONE;
1253 }
1254
1255 if (po->tp_version == TPACKET_V3) {
1256 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1257 ret = ROOM_NORMAL;
1258 else if (__tpacket_v3_has_room(po, 0))
1259 ret = ROOM_LOW;
1260 } else {
1261 if (__tpacket_has_room(po, ROOM_POW_OFF))
1262 ret = ROOM_NORMAL;
1263 else if (__tpacket_has_room(po, 0))
1264 ret = ROOM_LOW;
1265 }
1266
1267 return ret;
1268}
1269
1270static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1271{
1272 int pressure, ret;
1273
1274 ret = __packet_rcv_has_room(po, skb);
1275 pressure = ret != ROOM_NORMAL;
1276
1277 if (READ_ONCE(po->pressure) != pressure)
1278 WRITE_ONCE(po->pressure, pressure);
1279
1280 return ret;
1281}
1282
1283static void packet_rcv_try_clear_pressure(struct packet_sock *po)
1284{
1285 if (READ_ONCE(po->pressure) &&
1286 __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
1287 WRITE_ONCE(po->pressure, 0);
1288}
1289
1290static void packet_sock_destruct(struct sock *sk)
1291{
1292 skb_queue_purge(&sk->sk_error_queue);
1293
1294 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1295 WARN_ON(refcount_read(&sk->sk_wmem_alloc));
1296
1297 if (!sock_flag(sk, SOCK_DEAD)) {
1298 pr_err("Attempt to release alive packet socket: %p\n", sk);
1299 return;
1300 }
1301
1302 sk_refcnt_debug_dec(sk);
1303}
1304
1305static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1306{
1307 u32 *history = po->rollover->history;
1308 u32 victim, rxhash;
1309 int i, count = 0;
1310
1311 rxhash = skb_get_hash(skb);
1312 for (i = 0; i < ROLLOVER_HLEN; i++)
1313 if (READ_ONCE(history[i]) == rxhash)
1314 count++;
1315
1316 victim = prandom_u32() % ROLLOVER_HLEN;
1317
1318 /* Avoid dirtying the cache line if possible */
1319 if (READ_ONCE(history[victim]) != rxhash)
1320 WRITE_ONCE(history[victim], rxhash);
1321
1322 return count > (ROLLOVER_HLEN >> 1);
1323}
1324
1325static unsigned int fanout_demux_hash(struct packet_fanout *f,
1326 struct sk_buff *skb,
1327 unsigned int num)
1328{
1329 return reciprocal_scale(__skb_get_hash_symmetric(skb), num);
1330}
1331
1332static unsigned int fanout_demux_lb(struct packet_fanout *f,
1333 struct sk_buff *skb,
1334 unsigned int num)
1335{
1336 unsigned int val = atomic_inc_return(&f->rr_cur);
1337
1338 return val % num;
1339}
1340
1341static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1342 struct sk_buff *skb,
1343 unsigned int num)
1344{
1345 return smp_processor_id() % num;
1346}
1347
1348static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1349 struct sk_buff *skb,
1350 unsigned int num)
1351{
1352 return prandom_u32_max(num);
1353}
1354
1355static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1356 struct sk_buff *skb,
1357 unsigned int idx, bool try_self,
1358 unsigned int num)
1359{
1360 struct packet_sock *po, *po_next, *po_skip = NULL;
1361 unsigned int i, j, room = ROOM_NONE;
1362
1363 po = pkt_sk(rcu_dereference(f->arr[idx]));
1364
1365 if (try_self) {
1366 room = packet_rcv_has_room(po, skb);
1367 if (room == ROOM_NORMAL ||
1368 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1369 return idx;
1370 po_skip = po;
1371 }
1372
1373 i = j = min_t(int, po->rollover->sock, num - 1);
1374 do {
1375 po_next = pkt_sk(rcu_dereference(f->arr[i]));
1376 if (po_next != po_skip && !READ_ONCE(po_next->pressure) &&
1377 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1378 if (i != j)
1379 po->rollover->sock = i;
1380 atomic_long_inc(&po->rollover->num);
1381 if (room == ROOM_LOW)
1382 atomic_long_inc(&po->rollover->num_huge);
1383 return i;
1384 }
1385
1386 if (++i == num)
1387 i = 0;
1388 } while (i != j);
1389
1390 atomic_long_inc(&po->rollover->num_failed);
1391 return idx;
1392}
1393
1394static unsigned int fanout_demux_qm(struct packet_fanout *f,
1395 struct sk_buff *skb,
1396 unsigned int num)
1397{
1398 return skb_get_queue_mapping(skb) % num;
1399}
1400
1401static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1402 struct sk_buff *skb,
1403 unsigned int num)
1404{
1405 struct bpf_prog *prog;
1406 unsigned int ret = 0;
1407
1408 rcu_read_lock();
1409 prog = rcu_dereference(f->bpf_prog);
1410 if (prog)
1411 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1412 rcu_read_unlock();
1413
1414 return ret;
1415}
1416
1417static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1418{
1419 return f->flags & (flag >> 8);
1420}
1421
1422static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1423 struct packet_type *pt, struct net_device *orig_dev)
1424{
1425 struct packet_fanout *f = pt->af_packet_priv;
1426 unsigned int num = READ_ONCE(f->num_members);
1427 struct net *net = read_pnet(&f->net);
1428 struct packet_sock *po;
1429 unsigned int idx;
1430
1431 if (!net_eq(dev_net(dev), net) || !num) {
1432 kfree_skb(skb);
1433 return 0;
1434 }
1435
1436 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1437 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1438 if (!skb)
1439 return 0;
1440 }
1441 switch (f->type) {
1442 case PACKET_FANOUT_HASH:
1443 default:
1444 idx = fanout_demux_hash(f, skb, num);
1445 break;
1446 case PACKET_FANOUT_LB:
1447 idx = fanout_demux_lb(f, skb, num);
1448 break;
1449 case PACKET_FANOUT_CPU:
1450 idx = fanout_demux_cpu(f, skb, num);
1451 break;
1452 case PACKET_FANOUT_RND:
1453 idx = fanout_demux_rnd(f, skb, num);
1454 break;
1455 case PACKET_FANOUT_QM:
1456 idx = fanout_demux_qm(f, skb, num);
1457 break;
1458 case PACKET_FANOUT_ROLLOVER:
1459 idx = fanout_demux_rollover(f, skb, 0, false, num);
1460 break;
1461 case PACKET_FANOUT_CBPF:
1462 case PACKET_FANOUT_EBPF:
1463 idx = fanout_demux_bpf(f, skb, num);
1464 break;
1465 }
1466
1467 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1468 idx = fanout_demux_rollover(f, skb, idx, true, num);
1469
1470 po = pkt_sk(rcu_dereference(f->arr[idx]));
1471 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1472}
1473
1474DEFINE_MUTEX(fanout_mutex);
1475EXPORT_SYMBOL_GPL(fanout_mutex);
1476static LIST_HEAD(fanout_list);
1477static u16 fanout_next_id;
1478
1479static void __fanout_link(struct sock *sk, struct packet_sock *po)
1480{
1481 struct packet_fanout *f = po->fanout;
1482
1483 spin_lock(&f->lock);
1484 rcu_assign_pointer(f->arr[f->num_members], sk);
1485 smp_wmb();
1486 f->num_members++;
1487 if (f->num_members == 1)
1488 dev_add_pack(&f->prot_hook);
1489 spin_unlock(&f->lock);
1490}
1491
1492static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1493{
1494 struct packet_fanout *f = po->fanout;
1495 int i;
1496
1497 spin_lock(&f->lock);
1498 for (i = 0; i < f->num_members; i++) {
1499 if (rcu_dereference_protected(f->arr[i],
1500 lockdep_is_held(&f->lock)) == sk)
1501 break;
1502 }
1503 BUG_ON(i >= f->num_members);
1504 rcu_assign_pointer(f->arr[i],
1505 rcu_dereference_protected(f->arr[f->num_members - 1],
1506 lockdep_is_held(&f->lock)));
1507 f->num_members--;
1508 if (f->num_members == 0)
1509 __dev_remove_pack(&f->prot_hook);
1510 spin_unlock(&f->lock);
1511}
1512
1513static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1514{
1515 if (sk->sk_family != PF_PACKET)
1516 return false;
1517
1518 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1519}
1520
1521static void fanout_init_data(struct packet_fanout *f)
1522{
1523 switch (f->type) {
1524 case PACKET_FANOUT_LB:
1525 atomic_set(&f->rr_cur, 0);
1526 break;
1527 case PACKET_FANOUT_CBPF:
1528 case PACKET_FANOUT_EBPF:
1529 RCU_INIT_POINTER(f->bpf_prog, NULL);
1530 break;
1531 }
1532}
1533
1534static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1535{
1536 struct bpf_prog *old;
1537
1538 spin_lock(&f->lock);
1539 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1540 rcu_assign_pointer(f->bpf_prog, new);
1541 spin_unlock(&f->lock);
1542
1543 if (old) {
1544 synchronize_net();
1545 bpf_prog_destroy(old);
1546 }
1547}
1548
1549static int fanout_set_data_cbpf(struct packet_sock *po, sockptr_t data,
1550 unsigned int len)
1551{
1552 struct bpf_prog *new;
1553 struct sock_fprog fprog;
1554 int ret;
1555
1556 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1557 return -EPERM;
1558
1559 ret = copy_bpf_fprog_from_user(&fprog, data, len);
1560 if (ret)
1561 return ret;
1562
1563 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1564 if (ret)
1565 return ret;
1566
1567 __fanout_set_data_bpf(po->fanout, new);
1568 return 0;
1569}
1570
1571static int fanout_set_data_ebpf(struct packet_sock *po, sockptr_t data,
1572 unsigned int len)
1573{
1574 struct bpf_prog *new;
1575 u32 fd;
1576
1577 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1578 return -EPERM;
1579 if (len != sizeof(fd))
1580 return -EINVAL;
1581 if (copy_from_sockptr(&fd, data, len))
1582 return -EFAULT;
1583
1584 new = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
1585 if (IS_ERR(new))
1586 return PTR_ERR(new);
1587
1588 __fanout_set_data_bpf(po->fanout, new);
1589 return 0;
1590}
1591
1592static int fanout_set_data(struct packet_sock *po, sockptr_t data,
1593 unsigned int len)
1594{
1595 switch (po->fanout->type) {
1596 case PACKET_FANOUT_CBPF:
1597 return fanout_set_data_cbpf(po, data, len);
1598 case PACKET_FANOUT_EBPF:
1599 return fanout_set_data_ebpf(po, data, len);
1600 default:
1601 return -EINVAL;
1602 }
1603}
1604
1605static void fanout_release_data(struct packet_fanout *f)
1606{
1607 switch (f->type) {
1608 case PACKET_FANOUT_CBPF:
1609 case PACKET_FANOUT_EBPF:
1610 __fanout_set_data_bpf(f, NULL);
1611 }
1612}
1613
1614static bool __fanout_id_is_free(struct sock *sk, u16 candidate_id)
1615{
1616 struct packet_fanout *f;
1617
1618 list_for_each_entry(f, &fanout_list, list) {
1619 if (f->id == candidate_id &&
1620 read_pnet(&f->net) == sock_net(sk)) {
1621 return false;
1622 }
1623 }
1624 return true;
1625}
1626
1627static bool fanout_find_new_id(struct sock *sk, u16 *new_id)
1628{
1629 u16 id = fanout_next_id;
1630
1631 do {
1632 if (__fanout_id_is_free(sk, id)) {
1633 *new_id = id;
1634 fanout_next_id = id + 1;
1635 return true;
1636 }
1637
1638 id++;
1639 } while (id != fanout_next_id);
1640
1641 return false;
1642}
1643
1644static int fanout_add(struct sock *sk, struct fanout_args *args)
1645{
1646 struct packet_rollover *rollover = NULL;
1647 struct packet_sock *po = pkt_sk(sk);
1648 u16 type_flags = args->type_flags;
1649 struct packet_fanout *f, *match;
1650 u8 type = type_flags & 0xff;
1651 u8 flags = type_flags >> 8;
1652 u16 id = args->id;
1653 int err;
1654
1655 switch (type) {
1656 case PACKET_FANOUT_ROLLOVER:
1657 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1658 return -EINVAL;
1659 break;
1660 case PACKET_FANOUT_HASH:
1661 case PACKET_FANOUT_LB:
1662 case PACKET_FANOUT_CPU:
1663 case PACKET_FANOUT_RND:
1664 case PACKET_FANOUT_QM:
1665 case PACKET_FANOUT_CBPF:
1666 case PACKET_FANOUT_EBPF:
1667 break;
1668 default:
1669 return -EINVAL;
1670 }
1671
1672 mutex_lock(&fanout_mutex);
1673
1674 err = -EALREADY;
1675 if (po->fanout)
1676 goto out;
1677
1678 if (type == PACKET_FANOUT_ROLLOVER ||
1679 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1680 err = -ENOMEM;
1681 rollover = kzalloc(sizeof(*rollover), GFP_KERNEL);
1682 if (!rollover)
1683 goto out;
1684 atomic_long_set(&rollover->num, 0);
1685 atomic_long_set(&rollover->num_huge, 0);
1686 atomic_long_set(&rollover->num_failed, 0);
1687 }
1688
1689 if (type_flags & PACKET_FANOUT_FLAG_UNIQUEID) {
1690 if (id != 0) {
1691 err = -EINVAL;
1692 goto out;
1693 }
1694 if (!fanout_find_new_id(sk, &id)) {
1695 err = -ENOMEM;
1696 goto out;
1697 }
1698 /* ephemeral flag for the first socket in the group: drop it */
1699 flags &= ~(PACKET_FANOUT_FLAG_UNIQUEID >> 8);
1700 }
1701
1702 match = NULL;
1703 list_for_each_entry(f, &fanout_list, list) {
1704 if (f->id == id &&
1705 read_pnet(&f->net) == sock_net(sk)) {
1706 match = f;
1707 break;
1708 }
1709 }
1710 err = -EINVAL;
1711 if (match) {
1712 if (match->flags != flags)
1713 goto out;
1714 if (args->max_num_members &&
1715 args->max_num_members != match->max_num_members)
1716 goto out;
1717 } else {
1718 if (args->max_num_members > PACKET_FANOUT_MAX)
1719 goto out;
1720 if (!args->max_num_members)
1721 /* legacy PACKET_FANOUT_MAX */
1722 args->max_num_members = 256;
1723 err = -ENOMEM;
1724 match = kvzalloc(struct_size(match, arr, args->max_num_members),
1725 GFP_KERNEL);
1726 if (!match)
1727 goto out;
1728 write_pnet(&match->net, sock_net(sk));
1729 match->id = id;
1730 match->type = type;
1731 match->flags = flags;
1732 INIT_LIST_HEAD(&match->list);
1733 spin_lock_init(&match->lock);
1734 refcount_set(&match->sk_ref, 0);
1735 fanout_init_data(match);
1736 match->prot_hook.type = po->prot_hook.type;
1737 match->prot_hook.dev = po->prot_hook.dev;
1738 match->prot_hook.func = packet_rcv_fanout;
1739 match->prot_hook.af_packet_priv = match;
1740 match->prot_hook.id_match = match_fanout_group;
1741 match->max_num_members = args->max_num_members;
1742 list_add(&match->list, &fanout_list);
1743 }
1744 err = -EINVAL;
1745
1746 spin_lock(&po->bind_lock);
1747 if (po->running &&
1748 match->type == type &&
1749 match->prot_hook.type == po->prot_hook.type &&
1750 match->prot_hook.dev == po->prot_hook.dev) {
1751 err = -ENOSPC;
1752 if (refcount_read(&match->sk_ref) < match->max_num_members) {
1753 __dev_remove_pack(&po->prot_hook);
1754 po->fanout = match;
1755 po->rollover = rollover;
1756 rollover = NULL;
1757 refcount_set(&match->sk_ref, refcount_read(&match->sk_ref) + 1);
1758 __fanout_link(sk, po);
1759 err = 0;
1760 }
1761 }
1762 spin_unlock(&po->bind_lock);
1763
1764 if (err && !refcount_read(&match->sk_ref)) {
1765 list_del(&match->list);
1766 kvfree(match);
1767 }
1768
1769out:
1770 kfree(rollover);
1771 mutex_unlock(&fanout_mutex);
1772 return err;
1773}
1774
1775/* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes
1776 * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout.
1777 * It is the responsibility of the caller to call fanout_release_data() and
1778 * free the returned packet_fanout (after synchronize_net())
1779 */
1780static struct packet_fanout *fanout_release(struct sock *sk)
1781{
1782 struct packet_sock *po = pkt_sk(sk);
1783 struct packet_fanout *f;
1784
1785 mutex_lock(&fanout_mutex);
1786 f = po->fanout;
1787 if (f) {
1788 po->fanout = NULL;
1789
1790 if (refcount_dec_and_test(&f->sk_ref))
1791 list_del(&f->list);
1792 else
1793 f = NULL;
1794 }
1795 mutex_unlock(&fanout_mutex);
1796
1797 return f;
1798}
1799
1800static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1801 struct sk_buff *skb)
1802{
1803 /* Earlier code assumed this would be a VLAN pkt, double-check
1804 * this now that we have the actual packet in hand. We can only
1805 * do this check on Ethernet devices.
1806 */
1807 if (unlikely(dev->type != ARPHRD_ETHER))
1808 return false;
1809
1810 skb_reset_mac_header(skb);
1811 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1812}
1813
1814static const struct proto_ops packet_ops;
1815
1816static const struct proto_ops packet_ops_spkt;
1817
1818static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1819 struct packet_type *pt, struct net_device *orig_dev)
1820{
1821 struct sock *sk;
1822 struct sockaddr_pkt *spkt;
1823
1824 /*
1825 * When we registered the protocol we saved the socket in the data
1826 * field for just this event.
1827 */
1828
1829 sk = pt->af_packet_priv;
1830
1831 /*
1832 * Yank back the headers [hope the device set this
1833 * right or kerboom...]
1834 *
1835 * Incoming packets have ll header pulled,
1836 * push it back.
1837 *
1838 * For outgoing ones skb->data == skb_mac_header(skb)
1839 * so that this procedure is noop.
1840 */
1841
1842 if (skb->pkt_type == PACKET_LOOPBACK)
1843 goto out;
1844
1845 if (!net_eq(dev_net(dev), sock_net(sk)))
1846 goto out;
1847
1848 skb = skb_share_check(skb, GFP_ATOMIC);
1849 if (skb == NULL)
1850 goto oom;
1851
1852 /* drop any routing info */
1853 skb_dst_drop(skb);
1854
1855 /* drop conntrack reference */
1856 nf_reset_ct(skb);
1857
1858 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1859
1860 skb_push(skb, skb->data - skb_mac_header(skb));
1861
1862 /*
1863 * The SOCK_PACKET socket receives _all_ frames.
1864 */
1865
1866 spkt->spkt_family = dev->type;
1867 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1868 spkt->spkt_protocol = skb->protocol;
1869
1870 /*
1871 * Charge the memory to the socket. This is done specifically
1872 * to prevent sockets using all the memory up.
1873 */
1874
1875 if (sock_queue_rcv_skb(sk, skb) == 0)
1876 return 0;
1877
1878out:
1879 kfree_skb(skb);
1880oom:
1881 return 0;
1882}
1883
1884static void packet_parse_headers(struct sk_buff *skb, struct socket *sock)
1885{
1886 if ((!skb->protocol || skb->protocol == htons(ETH_P_ALL)) &&
1887 sock->type == SOCK_RAW) {
1888 skb_reset_mac_header(skb);
1889 skb->protocol = dev_parse_header_protocol(skb);
1890 }
1891
1892 skb_probe_transport_header(skb);
1893}
1894
1895/*
1896 * Output a raw packet to a device layer. This bypasses all the other
1897 * protocol layers and you must therefore supply it with a complete frame
1898 */
1899
1900static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1901 size_t len)
1902{
1903 struct sock *sk = sock->sk;
1904 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1905 struct sk_buff *skb = NULL;
1906 struct net_device *dev;
1907 struct sockcm_cookie sockc;
1908 __be16 proto = 0;
1909 int err;
1910 int extra_len = 0;
1911
1912 /*
1913 * Get and verify the address.
1914 */
1915
1916 if (saddr) {
1917 if (msg->msg_namelen < sizeof(struct sockaddr))
1918 return -EINVAL;
1919 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1920 proto = saddr->spkt_protocol;
1921 } else
1922 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1923
1924 /*
1925 * Find the device first to size check it
1926 */
1927
1928 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1929retry:
1930 rcu_read_lock();
1931 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1932 err = -ENODEV;
1933 if (dev == NULL)
1934 goto out_unlock;
1935
1936 err = -ENETDOWN;
1937 if (!(dev->flags & IFF_UP))
1938 goto out_unlock;
1939
1940 /*
1941 * You may not queue a frame bigger than the mtu. This is the lowest level
1942 * raw protocol and you must do your own fragmentation at this level.
1943 */
1944
1945 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1946 if (!netif_supports_nofcs(dev)) {
1947 err = -EPROTONOSUPPORT;
1948 goto out_unlock;
1949 }
1950 extra_len = 4; /* We're doing our own CRC */
1951 }
1952
1953 err = -EMSGSIZE;
1954 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1955 goto out_unlock;
1956
1957 if (!skb) {
1958 size_t reserved = LL_RESERVED_SPACE(dev);
1959 int tlen = dev->needed_tailroom;
1960 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1961
1962 rcu_read_unlock();
1963 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1964 if (skb == NULL)
1965 return -ENOBUFS;
1966 /* FIXME: Save some space for broken drivers that write a hard
1967 * header at transmission time by themselves. PPP is the notable
1968 * one here. This should really be fixed at the driver level.
1969 */
1970 skb_reserve(skb, reserved);
1971 skb_reset_network_header(skb);
1972
1973 /* Try to align data part correctly */
1974 if (hhlen) {
1975 skb->data -= hhlen;
1976 skb->tail -= hhlen;
1977 if (len < hhlen)
1978 skb_reset_network_header(skb);
1979 }
1980 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1981 if (err)
1982 goto out_free;
1983 goto retry;
1984 }
1985
1986 if (!dev_validate_header(dev, skb->data, len)) {
1987 err = -EINVAL;
1988 goto out_unlock;
1989 }
1990 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
1991 !packet_extra_vlan_len_allowed(dev, skb)) {
1992 err = -EMSGSIZE;
1993 goto out_unlock;
1994 }
1995
1996 sockcm_init(&sockc, sk);
1997 if (msg->msg_controllen) {
1998 err = sock_cmsg_send(sk, msg, &sockc);
1999 if (unlikely(err))
2000 goto out_unlock;
2001 }
2002
2003 skb->protocol = proto;
2004 skb->dev = dev;
2005 skb->priority = sk->sk_priority;
2006 skb->mark = sk->sk_mark;
2007 skb->tstamp = sockc.transmit_time;
2008
2009 skb_setup_tx_timestamp(skb, sockc.tsflags);
2010
2011 if (unlikely(extra_len == 4))
2012 skb->no_fcs = 1;
2013
2014 packet_parse_headers(skb, sock);
2015
2016 dev_queue_xmit(skb);
2017 rcu_read_unlock();
2018 return len;
2019
2020out_unlock:
2021 rcu_read_unlock();
2022out_free:
2023 kfree_skb(skb);
2024 return err;
2025}
2026
2027static unsigned int run_filter(struct sk_buff *skb,
2028 const struct sock *sk,
2029 unsigned int res)
2030{
2031 struct sk_filter *filter;
2032
2033 rcu_read_lock();
2034 filter = rcu_dereference(sk->sk_filter);
2035 if (filter != NULL)
2036 res = bpf_prog_run_clear_cb(filter->prog, skb);
2037 rcu_read_unlock();
2038
2039 return res;
2040}
2041
2042static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
2043 size_t *len)
2044{
2045 struct virtio_net_hdr vnet_hdr;
2046
2047 if (*len < sizeof(vnet_hdr))
2048 return -EINVAL;
2049 *len -= sizeof(vnet_hdr);
2050
2051 if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le(), true, 0))
2052 return -EINVAL;
2053
2054 return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
2055}
2056
2057/*
2058 * This function makes lazy skb cloning in hope that most of packets
2059 * are discarded by BPF.
2060 *
2061 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2062 * and skb->cb are mangled. It works because (and until) packets
2063 * falling here are owned by current CPU. Output packets are cloned
2064 * by dev_queue_xmit_nit(), input packets are processed by net_bh
2065 * sequentially, so that if we return skb to original state on exit,
2066 * we will not harm anyone.
2067 */
2068
2069static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2070 struct packet_type *pt, struct net_device *orig_dev)
2071{
2072 struct sock *sk;
2073 struct sockaddr_ll *sll;
2074 struct packet_sock *po;
2075 u8 *skb_head = skb->data;
2076 int skb_len = skb->len;
2077 unsigned int snaplen, res;
2078 bool is_drop_n_account = false;
2079
2080 if (skb->pkt_type == PACKET_LOOPBACK)
2081 goto drop;
2082
2083 sk = pt->af_packet_priv;
2084 po = pkt_sk(sk);
2085
2086 if (!net_eq(dev_net(dev), sock_net(sk)))
2087 goto drop;
2088
2089 skb->dev = dev;
2090
2091 if (dev_has_header(dev)) {
2092 /* The device has an explicit notion of ll header,
2093 * exported to higher levels.
2094 *
2095 * Otherwise, the device hides details of its frame
2096 * structure, so that corresponding packet head is
2097 * never delivered to user.
2098 */
2099 if (sk->sk_type != SOCK_DGRAM)
2100 skb_push(skb, skb->data - skb_mac_header(skb));
2101 else if (skb->pkt_type == PACKET_OUTGOING) {
2102 /* Special case: outgoing packets have ll header at head */
2103 skb_pull(skb, skb_network_offset(skb));
2104 }
2105 }
2106
2107 snaplen = skb->len;
2108
2109 res = run_filter(skb, sk, snaplen);
2110 if (!res)
2111 goto drop_n_restore;
2112 if (snaplen > res)
2113 snaplen = res;
2114
2115 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2116 goto drop_n_acct;
2117
2118 if (skb_shared(skb)) {
2119 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2120 if (nskb == NULL)
2121 goto drop_n_acct;
2122
2123 if (skb_head != skb->data) {
2124 skb->data = skb_head;
2125 skb->len = skb_len;
2126 }
2127 consume_skb(skb);
2128 skb = nskb;
2129 }
2130
2131 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2132
2133 sll = &PACKET_SKB_CB(skb)->sa.ll;
2134 sll->sll_hatype = dev->type;
2135 sll->sll_pkttype = skb->pkt_type;
2136 if (unlikely(po->origdev))
2137 sll->sll_ifindex = orig_dev->ifindex;
2138 else
2139 sll->sll_ifindex = dev->ifindex;
2140
2141 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2142
2143 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2144 * Use their space for storing the original skb length.
2145 */
2146 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2147
2148 if (pskb_trim(skb, snaplen))
2149 goto drop_n_acct;
2150
2151 skb_set_owner_r(skb, sk);
2152 skb->dev = NULL;
2153 skb_dst_drop(skb);
2154
2155 /* drop conntrack reference */
2156 nf_reset_ct(skb);
2157
2158 spin_lock(&sk->sk_receive_queue.lock);
2159 po->stats.stats1.tp_packets++;
2160 sock_skb_set_dropcount(sk, skb);
2161 __skb_queue_tail(&sk->sk_receive_queue, skb);
2162 spin_unlock(&sk->sk_receive_queue.lock);
2163 sk->sk_data_ready(sk);
2164 return 0;
2165
2166drop_n_acct:
2167 is_drop_n_account = true;
2168 atomic_inc(&po->tp_drops);
2169 atomic_inc(&sk->sk_drops);
2170
2171drop_n_restore:
2172 if (skb_head != skb->data && skb_shared(skb)) {
2173 skb->data = skb_head;
2174 skb->len = skb_len;
2175 }
2176drop:
2177 if (!is_drop_n_account)
2178 consume_skb(skb);
2179 else
2180 kfree_skb(skb);
2181 return 0;
2182}
2183
2184static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2185 struct packet_type *pt, struct net_device *orig_dev)
2186{
2187 struct sock *sk;
2188 struct packet_sock *po;
2189 struct sockaddr_ll *sll;
2190 union tpacket_uhdr h;
2191 u8 *skb_head = skb->data;
2192 int skb_len = skb->len;
2193 unsigned int snaplen, res;
2194 unsigned long status = TP_STATUS_USER;
2195 unsigned short macoff, hdrlen;
2196 unsigned int netoff;
2197 struct sk_buff *copy_skb = NULL;
2198 struct timespec64 ts;
2199 __u32 ts_status;
2200 bool is_drop_n_account = false;
2201 unsigned int slot_id = 0;
2202 bool do_vnet = false;
2203
2204 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2205 * We may add members to them until current aligned size without forcing
2206 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2207 */
2208 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2209 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2210
2211 if (skb->pkt_type == PACKET_LOOPBACK)
2212 goto drop;
2213
2214 sk = pt->af_packet_priv;
2215 po = pkt_sk(sk);
2216
2217 if (!net_eq(dev_net(dev), sock_net(sk)))
2218 goto drop;
2219
2220 if (dev_has_header(dev)) {
2221 if (sk->sk_type != SOCK_DGRAM)
2222 skb_push(skb, skb->data - skb_mac_header(skb));
2223 else if (skb->pkt_type == PACKET_OUTGOING) {
2224 /* Special case: outgoing packets have ll header at head */
2225 skb_pull(skb, skb_network_offset(skb));
2226 }
2227 }
2228
2229 snaplen = skb->len;
2230
2231 res = run_filter(skb, sk, snaplen);
2232 if (!res)
2233 goto drop_n_restore;
2234
2235 /* If we are flooded, just give up */
2236 if (__packet_rcv_has_room(po, skb) == ROOM_NONE) {
2237 atomic_inc(&po->tp_drops);
2238 goto drop_n_restore;
2239 }
2240
2241 if (skb->ip_summed == CHECKSUM_PARTIAL)
2242 status |= TP_STATUS_CSUMNOTREADY;
2243 else if (skb->pkt_type != PACKET_OUTGOING &&
2244 (skb->ip_summed == CHECKSUM_COMPLETE ||
2245 skb_csum_unnecessary(skb)))
2246 status |= TP_STATUS_CSUM_VALID;
2247
2248 if (snaplen > res)
2249 snaplen = res;
2250
2251 if (sk->sk_type == SOCK_DGRAM) {
2252 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2253 po->tp_reserve;
2254 } else {
2255 unsigned int maclen = skb_network_offset(skb);
2256 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2257 (maclen < 16 ? 16 : maclen)) +
2258 po->tp_reserve;
2259 if (po->has_vnet_hdr) {
2260 netoff += sizeof(struct virtio_net_hdr);
2261 do_vnet = true;
2262 }
2263 macoff = netoff - maclen;
2264 }
2265 if (netoff > USHRT_MAX) {
2266 atomic_inc(&po->tp_drops);
2267 goto drop_n_restore;
2268 }
2269 if (po->tp_version <= TPACKET_V2) {
2270 if (macoff + snaplen > po->rx_ring.frame_size) {
2271 if (po->copy_thresh &&
2272 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2273 if (skb_shared(skb)) {
2274 copy_skb = skb_clone(skb, GFP_ATOMIC);
2275 } else {
2276 copy_skb = skb_get(skb);
2277 skb_head = skb->data;
2278 }
2279 if (copy_skb)
2280 skb_set_owner_r(copy_skb, sk);
2281 }
2282 snaplen = po->rx_ring.frame_size - macoff;
2283 if ((int)snaplen < 0) {
2284 snaplen = 0;
2285 do_vnet = false;
2286 }
2287 }
2288 } else if (unlikely(macoff + snaplen >
2289 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2290 u32 nval;
2291
2292 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2293 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2294 snaplen, nval, macoff);
2295 snaplen = nval;
2296 if (unlikely((int)snaplen < 0)) {
2297 snaplen = 0;
2298 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2299 do_vnet = false;
2300 }
2301 }
2302 spin_lock(&sk->sk_receive_queue.lock);
2303 h.raw = packet_current_rx_frame(po, skb,
2304 TP_STATUS_KERNEL, (macoff+snaplen));
2305 if (!h.raw)
2306 goto drop_n_account;
2307
2308 if (po->tp_version <= TPACKET_V2) {
2309 slot_id = po->rx_ring.head;
2310 if (test_bit(slot_id, po->rx_ring.rx_owner_map))
2311 goto drop_n_account;
2312 __set_bit(slot_id, po->rx_ring.rx_owner_map);
2313 }
2314
2315 if (do_vnet &&
2316 virtio_net_hdr_from_skb(skb, h.raw + macoff -
2317 sizeof(struct virtio_net_hdr),
2318 vio_le(), true, 0)) {
2319 if (po->tp_version == TPACKET_V3)
2320 prb_clear_blk_fill_status(&po->rx_ring);
2321 goto drop_n_account;
2322 }
2323
2324 if (po->tp_version <= TPACKET_V2) {
2325 packet_increment_rx_head(po, &po->rx_ring);
2326 /*
2327 * LOSING will be reported till you read the stats,
2328 * because it's COR - Clear On Read.
2329 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2330 * at packet level.
2331 */
2332 if (atomic_read(&po->tp_drops))
2333 status |= TP_STATUS_LOSING;
2334 }
2335
2336 po->stats.stats1.tp_packets++;
2337 if (copy_skb) {
2338 status |= TP_STATUS_COPY;
2339 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2340 }
2341 spin_unlock(&sk->sk_receive_queue.lock);
2342
2343 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2344
2345 /* Always timestamp; prefer an existing software timestamp taken
2346 * closer to the time of capture.
2347 */
2348 ts_status = tpacket_get_timestamp(skb, &ts,
2349 po->tp_tstamp | SOF_TIMESTAMPING_SOFTWARE);
2350 if (!ts_status)
2351 ktime_get_real_ts64(&ts);
2352
2353 status |= ts_status;
2354
2355 switch (po->tp_version) {
2356 case TPACKET_V1:
2357 h.h1->tp_len = skb->len;
2358 h.h1->tp_snaplen = snaplen;
2359 h.h1->tp_mac = macoff;
2360 h.h1->tp_net = netoff;
2361 h.h1->tp_sec = ts.tv_sec;
2362 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2363 hdrlen = sizeof(*h.h1);
2364 break;
2365 case TPACKET_V2:
2366 h.h2->tp_len = skb->len;
2367 h.h2->tp_snaplen = snaplen;
2368 h.h2->tp_mac = macoff;
2369 h.h2->tp_net = netoff;
2370 h.h2->tp_sec = ts.tv_sec;
2371 h.h2->tp_nsec = ts.tv_nsec;
2372 if (skb_vlan_tag_present(skb)) {
2373 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2374 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2375 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2376 } else {
2377 h.h2->tp_vlan_tci = 0;
2378 h.h2->tp_vlan_tpid = 0;
2379 }
2380 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2381 hdrlen = sizeof(*h.h2);
2382 break;
2383 case TPACKET_V3:
2384 /* tp_nxt_offset,vlan are already populated above.
2385 * So DONT clear those fields here
2386 */
2387 h.h3->tp_status |= status;
2388 h.h3->tp_len = skb->len;
2389 h.h3->tp_snaplen = snaplen;
2390 h.h3->tp_mac = macoff;
2391 h.h3->tp_net = netoff;
2392 h.h3->tp_sec = ts.tv_sec;
2393 h.h3->tp_nsec = ts.tv_nsec;
2394 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2395 hdrlen = sizeof(*h.h3);
2396 break;
2397 default:
2398 BUG();
2399 }
2400
2401 sll = h.raw + TPACKET_ALIGN(hdrlen);
2402 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2403 sll->sll_family = AF_PACKET;
2404 sll->sll_hatype = dev->type;
2405 sll->sll_protocol = skb->protocol;
2406 sll->sll_pkttype = skb->pkt_type;
2407 if (unlikely(po->origdev))
2408 sll->sll_ifindex = orig_dev->ifindex;
2409 else
2410 sll->sll_ifindex = dev->ifindex;
2411
2412 smp_mb();
2413
2414#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2415 if (po->tp_version <= TPACKET_V2) {
2416 u8 *start, *end;
2417
2418 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2419 macoff + snaplen);
2420
2421 for (start = h.raw; start < end; start += PAGE_SIZE)
2422 flush_dcache_page(pgv_to_page(start));
2423 }
2424 smp_wmb();
2425#endif
2426
2427 if (po->tp_version <= TPACKET_V2) {
2428 spin_lock(&sk->sk_receive_queue.lock);
2429 __packet_set_status(po, h.raw, status);
2430 __clear_bit(slot_id, po->rx_ring.rx_owner_map);
2431 spin_unlock(&sk->sk_receive_queue.lock);
2432 sk->sk_data_ready(sk);
2433 } else if (po->tp_version == TPACKET_V3) {
2434 prb_clear_blk_fill_status(&po->rx_ring);
2435 }
2436
2437drop_n_restore:
2438 if (skb_head != skb->data && skb_shared(skb)) {
2439 skb->data = skb_head;
2440 skb->len = skb_len;
2441 }
2442drop:
2443 if (!is_drop_n_account)
2444 consume_skb(skb);
2445 else
2446 kfree_skb(skb);
2447 return 0;
2448
2449drop_n_account:
2450 spin_unlock(&sk->sk_receive_queue.lock);
2451 atomic_inc(&po->tp_drops);
2452 is_drop_n_account = true;
2453
2454 sk->sk_data_ready(sk);
2455 kfree_skb(copy_skb);
2456 goto drop_n_restore;
2457}
2458
2459static void tpacket_destruct_skb(struct sk_buff *skb)
2460{
2461 struct packet_sock *po = pkt_sk(skb->sk);
2462
2463 if (likely(po->tx_ring.pg_vec)) {
2464 void *ph;
2465 __u32 ts;
2466
2467 ph = skb_zcopy_get_nouarg(skb);
2468 packet_dec_pending(&po->tx_ring);
2469
2470 ts = __packet_set_timestamp(po, ph, skb);
2471 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2472
2473 if (!packet_read_pending(&po->tx_ring))
2474 complete(&po->skb_completion);
2475 }
2476
2477 sock_wfree(skb);
2478}
2479
2480static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2481{
2482 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2483 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2484 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2485 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2486 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2487 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2488 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2489
2490 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2491 return -EINVAL;
2492
2493 return 0;
2494}
2495
2496static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2497 struct virtio_net_hdr *vnet_hdr)
2498{
2499 if (*len < sizeof(*vnet_hdr))
2500 return -EINVAL;
2501 *len -= sizeof(*vnet_hdr);
2502
2503 if (!copy_from_iter_full(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter))
2504 return -EFAULT;
2505
2506 return __packet_snd_vnet_parse(vnet_hdr, *len);
2507}
2508
2509static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2510 void *frame, struct net_device *dev, void *data, int tp_len,
2511 __be16 proto, unsigned char *addr, int hlen, int copylen,
2512 const struct sockcm_cookie *sockc)
2513{
2514 union tpacket_uhdr ph;
2515 int to_write, offset, len, nr_frags, len_max;
2516 struct socket *sock = po->sk.sk_socket;
2517 struct page *page;
2518 int err;
2519
2520 ph.raw = frame;
2521
2522 skb->protocol = proto;
2523 skb->dev = dev;
2524 skb->priority = po->sk.sk_priority;
2525 skb->mark = po->sk.sk_mark;
2526 skb->tstamp = sockc->transmit_time;
2527 skb_setup_tx_timestamp(skb, sockc->tsflags);
2528 skb_zcopy_set_nouarg(skb, ph.raw);
2529
2530 skb_reserve(skb, hlen);
2531 skb_reset_network_header(skb);
2532
2533 to_write = tp_len;
2534
2535 if (sock->type == SOCK_DGRAM) {
2536 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2537 NULL, tp_len);
2538 if (unlikely(err < 0))
2539 return -EINVAL;
2540 } else if (copylen) {
2541 int hdrlen = min_t(int, copylen, tp_len);
2542
2543 skb_push(skb, dev->hard_header_len);
2544 skb_put(skb, copylen - dev->hard_header_len);
2545 err = skb_store_bits(skb, 0, data, hdrlen);
2546 if (unlikely(err))
2547 return err;
2548 if (!dev_validate_header(dev, skb->data, hdrlen))
2549 return -EINVAL;
2550
2551 data += hdrlen;
2552 to_write -= hdrlen;
2553 }
2554
2555 offset = offset_in_page(data);
2556 len_max = PAGE_SIZE - offset;
2557 len = ((to_write > len_max) ? len_max : to_write);
2558
2559 skb->data_len = to_write;
2560 skb->len += to_write;
2561 skb->truesize += to_write;
2562 refcount_add(to_write, &po->sk.sk_wmem_alloc);
2563
2564 while (likely(to_write)) {
2565 nr_frags = skb_shinfo(skb)->nr_frags;
2566
2567 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2568 pr_err("Packet exceed the number of skb frags(%lu)\n",
2569 MAX_SKB_FRAGS);
2570 return -EFAULT;
2571 }
2572
2573 page = pgv_to_page(data);
2574 data += len;
2575 flush_dcache_page(page);
2576 get_page(page);
2577 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2578 to_write -= len;
2579 offset = 0;
2580 len_max = PAGE_SIZE;
2581 len = ((to_write > len_max) ? len_max : to_write);
2582 }
2583
2584 packet_parse_headers(skb, sock);
2585
2586 return tp_len;
2587}
2588
2589static int tpacket_parse_header(struct packet_sock *po, void *frame,
2590 int size_max, void **data)
2591{
2592 union tpacket_uhdr ph;
2593 int tp_len, off;
2594
2595 ph.raw = frame;
2596
2597 switch (po->tp_version) {
2598 case TPACKET_V3:
2599 if (ph.h3->tp_next_offset != 0) {
2600 pr_warn_once("variable sized slot not supported");
2601 return -EINVAL;
2602 }
2603 tp_len = ph.h3->tp_len;
2604 break;
2605 case TPACKET_V2:
2606 tp_len = ph.h2->tp_len;
2607 break;
2608 default:
2609 tp_len = ph.h1->tp_len;
2610 break;
2611 }
2612 if (unlikely(tp_len > size_max)) {
2613 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2614 return -EMSGSIZE;
2615 }
2616
2617 if (unlikely(po->tp_tx_has_off)) {
2618 int off_min, off_max;
2619
2620 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2621 off_max = po->tx_ring.frame_size - tp_len;
2622 if (po->sk.sk_type == SOCK_DGRAM) {
2623 switch (po->tp_version) {
2624 case TPACKET_V3:
2625 off = ph.h3->tp_net;
2626 break;
2627 case TPACKET_V2:
2628 off = ph.h2->tp_net;
2629 break;
2630 default:
2631 off = ph.h1->tp_net;
2632 break;
2633 }
2634 } else {
2635 switch (po->tp_version) {
2636 case TPACKET_V3:
2637 off = ph.h3->tp_mac;
2638 break;
2639 case TPACKET_V2:
2640 off = ph.h2->tp_mac;
2641 break;
2642 default:
2643 off = ph.h1->tp_mac;
2644 break;
2645 }
2646 }
2647 if (unlikely((off < off_min) || (off_max < off)))
2648 return -EINVAL;
2649 } else {
2650 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2651 }
2652
2653 *data = frame + off;
2654 return tp_len;
2655}
2656
2657static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2658{
2659 struct sk_buff *skb = NULL;
2660 struct net_device *dev;
2661 struct virtio_net_hdr *vnet_hdr = NULL;
2662 struct sockcm_cookie sockc;
2663 __be16 proto;
2664 int err, reserve = 0;
2665 void *ph;
2666 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2667 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2668 unsigned char *addr = NULL;
2669 int tp_len, size_max;
2670 void *data;
2671 int len_sum = 0;
2672 int status = TP_STATUS_AVAILABLE;
2673 int hlen, tlen, copylen = 0;
2674 long timeo = 0;
2675
2676 mutex_lock(&po->pg_vec_lock);
2677
2678 /* packet_sendmsg() check on tx_ring.pg_vec was lockless,
2679 * we need to confirm it under protection of pg_vec_lock.
2680 */
2681 if (unlikely(!po->tx_ring.pg_vec)) {
2682 err = -EBUSY;
2683 goto out;
2684 }
2685 if (likely(saddr == NULL)) {
2686 dev = packet_cached_dev_get(po);
2687 proto = READ_ONCE(po->num);
2688 } else {
2689 err = -EINVAL;
2690 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2691 goto out;
2692 if (msg->msg_namelen < (saddr->sll_halen
2693 + offsetof(struct sockaddr_ll,
2694 sll_addr)))
2695 goto out;
2696 proto = saddr->sll_protocol;
2697 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2698 if (po->sk.sk_socket->type == SOCK_DGRAM) {
2699 if (dev && msg->msg_namelen < dev->addr_len +
2700 offsetof(struct sockaddr_ll, sll_addr))
2701 goto out_put;
2702 addr = saddr->sll_addr;
2703 }
2704 }
2705
2706 err = -ENXIO;
2707 if (unlikely(dev == NULL))
2708 goto out;
2709 err = -ENETDOWN;
2710 if (unlikely(!(dev->flags & IFF_UP)))
2711 goto out_put;
2712
2713 sockcm_init(&sockc, &po->sk);
2714 if (msg->msg_controllen) {
2715 err = sock_cmsg_send(&po->sk, msg, &sockc);
2716 if (unlikely(err))
2717 goto out_put;
2718 }
2719
2720 if (po->sk.sk_socket->type == SOCK_RAW)
2721 reserve = dev->hard_header_len;
2722 size_max = po->tx_ring.frame_size
2723 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2724
2725 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2726 size_max = dev->mtu + reserve + VLAN_HLEN;
2727
2728 reinit_completion(&po->skb_completion);
2729
2730 do {
2731 ph = packet_current_frame(po, &po->tx_ring,
2732 TP_STATUS_SEND_REQUEST);
2733 if (unlikely(ph == NULL)) {
2734 if (need_wait && skb) {
2735 timeo = sock_sndtimeo(&po->sk, msg->msg_flags & MSG_DONTWAIT);
2736 timeo = wait_for_completion_interruptible_timeout(&po->skb_completion, timeo);
2737 if (timeo <= 0) {
2738 err = !timeo ? -ETIMEDOUT : -ERESTARTSYS;
2739 goto out_put;
2740 }
2741 }
2742 /* check for additional frames */
2743 continue;
2744 }
2745
2746 skb = NULL;
2747 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2748 if (tp_len < 0)
2749 goto tpacket_error;
2750
2751 status = TP_STATUS_SEND_REQUEST;
2752 hlen = LL_RESERVED_SPACE(dev);
2753 tlen = dev->needed_tailroom;
2754 if (po->has_vnet_hdr) {
2755 vnet_hdr = data;
2756 data += sizeof(*vnet_hdr);
2757 tp_len -= sizeof(*vnet_hdr);
2758 if (tp_len < 0 ||
2759 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2760 tp_len = -EINVAL;
2761 goto tpacket_error;
2762 }
2763 copylen = __virtio16_to_cpu(vio_le(),
2764 vnet_hdr->hdr_len);
2765 }
2766 copylen = max_t(int, copylen, dev->hard_header_len);
2767 skb = sock_alloc_send_skb(&po->sk,
2768 hlen + tlen + sizeof(struct sockaddr_ll) +
2769 (copylen - dev->hard_header_len),
2770 !need_wait, &err);
2771
2772 if (unlikely(skb == NULL)) {
2773 /* we assume the socket was initially writeable ... */
2774 if (likely(len_sum > 0))
2775 err = len_sum;
2776 goto out_status;
2777 }
2778 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2779 addr, hlen, copylen, &sockc);
2780 if (likely(tp_len >= 0) &&
2781 tp_len > dev->mtu + reserve &&
2782 !po->has_vnet_hdr &&
2783 !packet_extra_vlan_len_allowed(dev, skb))
2784 tp_len = -EMSGSIZE;
2785
2786 if (unlikely(tp_len < 0)) {
2787tpacket_error:
2788 if (po->tp_loss) {
2789 __packet_set_status(po, ph,
2790 TP_STATUS_AVAILABLE);
2791 packet_increment_head(&po->tx_ring);
2792 kfree_skb(skb);
2793 continue;
2794 } else {
2795 status = TP_STATUS_WRONG_FORMAT;
2796 err = tp_len;
2797 goto out_status;
2798 }
2799 }
2800
2801 if (po->has_vnet_hdr) {
2802 if (virtio_net_hdr_to_skb(skb, vnet_hdr, vio_le())) {
2803 tp_len = -EINVAL;
2804 goto tpacket_error;
2805 }
2806 virtio_net_hdr_set_proto(skb, vnet_hdr);
2807 }
2808
2809 skb->destructor = tpacket_destruct_skb;
2810 __packet_set_status(po, ph, TP_STATUS_SENDING);
2811 packet_inc_pending(&po->tx_ring);
2812
2813 status = TP_STATUS_SEND_REQUEST;
2814 err = po->xmit(skb);
2815 if (unlikely(err > 0)) {
2816 err = net_xmit_errno(err);
2817 if (err && __packet_get_status(po, ph) ==
2818 TP_STATUS_AVAILABLE) {
2819 /* skb was destructed already */
2820 skb = NULL;
2821 goto out_status;
2822 }
2823 /*
2824 * skb was dropped but not destructed yet;
2825 * let's treat it like congestion or err < 0
2826 */
2827 err = 0;
2828 }
2829 packet_increment_head(&po->tx_ring);
2830 len_sum += tp_len;
2831 } while (likely((ph != NULL) ||
2832 /* Note: packet_read_pending() might be slow if we have
2833 * to call it as it's per_cpu variable, but in fast-path
2834 * we already short-circuit the loop with the first
2835 * condition, and luckily don't have to go that path
2836 * anyway.
2837 */
2838 (need_wait && packet_read_pending(&po->tx_ring))));
2839
2840 err = len_sum;
2841 goto out_put;
2842
2843out_status:
2844 __packet_set_status(po, ph, status);
2845 kfree_skb(skb);
2846out_put:
2847 dev_put(dev);
2848out:
2849 mutex_unlock(&po->pg_vec_lock);
2850 return err;
2851}
2852
2853static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2854 size_t reserve, size_t len,
2855 size_t linear, int noblock,
2856 int *err)
2857{
2858 struct sk_buff *skb;
2859
2860 /* Under a page? Don't bother with paged skb. */
2861 if (prepad + len < PAGE_SIZE || !linear)
2862 linear = len;
2863
2864 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2865 err, 0);
2866 if (!skb)
2867 return NULL;
2868
2869 skb_reserve(skb, reserve);
2870 skb_put(skb, linear);
2871 skb->data_len = len - linear;
2872 skb->len += len - linear;
2873
2874 return skb;
2875}
2876
2877static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2878{
2879 struct sock *sk = sock->sk;
2880 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2881 struct sk_buff *skb;
2882 struct net_device *dev;
2883 __be16 proto;
2884 unsigned char *addr = NULL;
2885 int err, reserve = 0;
2886 struct sockcm_cookie sockc;
2887 struct virtio_net_hdr vnet_hdr = { 0 };
2888 int offset = 0;
2889 struct packet_sock *po = pkt_sk(sk);
2890 bool has_vnet_hdr = false;
2891 int hlen, tlen, linear;
2892 int extra_len = 0;
2893
2894 /*
2895 * Get and verify the address.
2896 */
2897
2898 if (likely(saddr == NULL)) {
2899 dev = packet_cached_dev_get(po);
2900 proto = READ_ONCE(po->num);
2901 } else {
2902 err = -EINVAL;
2903 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2904 goto out;
2905 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2906 goto out;
2907 proto = saddr->sll_protocol;
2908 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2909 if (sock->type == SOCK_DGRAM) {
2910 if (dev && msg->msg_namelen < dev->addr_len +
2911 offsetof(struct sockaddr_ll, sll_addr))
2912 goto out_unlock;
2913 addr = saddr->sll_addr;
2914 }
2915 }
2916
2917 err = -ENXIO;
2918 if (unlikely(dev == NULL))
2919 goto out_unlock;
2920 err = -ENETDOWN;
2921 if (unlikely(!(dev->flags & IFF_UP)))
2922 goto out_unlock;
2923
2924 sockcm_init(&sockc, sk);
2925 sockc.mark = sk->sk_mark;
2926 if (msg->msg_controllen) {
2927 err = sock_cmsg_send(sk, msg, &sockc);
2928 if (unlikely(err))
2929 goto out_unlock;
2930 }
2931
2932 if (sock->type == SOCK_RAW)
2933 reserve = dev->hard_header_len;
2934 if (po->has_vnet_hdr) {
2935 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2936 if (err)
2937 goto out_unlock;
2938 has_vnet_hdr = true;
2939 }
2940
2941 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2942 if (!netif_supports_nofcs(dev)) {
2943 err = -EPROTONOSUPPORT;
2944 goto out_unlock;
2945 }
2946 extra_len = 4; /* We're doing our own CRC */
2947 }
2948
2949 err = -EMSGSIZE;
2950 if (!vnet_hdr.gso_type &&
2951 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2952 goto out_unlock;
2953
2954 err = -ENOBUFS;
2955 hlen = LL_RESERVED_SPACE(dev);
2956 tlen = dev->needed_tailroom;
2957 linear = __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len);
2958 linear = max(linear, min_t(int, len, dev->hard_header_len));
2959 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, linear,
2960 msg->msg_flags & MSG_DONTWAIT, &err);
2961 if (skb == NULL)
2962 goto out_unlock;
2963
2964 skb_reset_network_header(skb);
2965
2966 err = -EINVAL;
2967 if (sock->type == SOCK_DGRAM) {
2968 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2969 if (unlikely(offset < 0))
2970 goto out_free;
2971 } else if (reserve) {
2972 skb_reserve(skb, -reserve);
2973 if (len < reserve + sizeof(struct ipv6hdr) &&
2974 dev->min_header_len != dev->hard_header_len)
2975 skb_reset_network_header(skb);
2976 }
2977
2978 /* Returns -EFAULT on error */
2979 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2980 if (err)
2981 goto out_free;
2982
2983 if (sock->type == SOCK_RAW &&
2984 !dev_validate_header(dev, skb->data, len)) {
2985 err = -EINVAL;
2986 goto out_free;
2987 }
2988
2989 skb_setup_tx_timestamp(skb, sockc.tsflags);
2990
2991 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
2992 !packet_extra_vlan_len_allowed(dev, skb)) {
2993 err = -EMSGSIZE;
2994 goto out_free;
2995 }
2996
2997 skb->protocol = proto;
2998 skb->dev = dev;
2999 skb->priority = sk->sk_priority;
3000 skb->mark = sockc.mark;
3001 skb->tstamp = sockc.transmit_time;
3002
3003 if (has_vnet_hdr) {
3004 err = virtio_net_hdr_to_skb(skb, &vnet_hdr, vio_le());
3005 if (err)
3006 goto out_free;
3007 len += sizeof(vnet_hdr);
3008 virtio_net_hdr_set_proto(skb, &vnet_hdr);
3009 }
3010
3011 packet_parse_headers(skb, sock);
3012
3013 if (unlikely(extra_len == 4))
3014 skb->no_fcs = 1;
3015
3016 err = po->xmit(skb);
3017 if (err > 0 && (err = net_xmit_errno(err)) != 0)
3018 goto out_unlock;
3019
3020 dev_put(dev);
3021
3022 return len;
3023
3024out_free:
3025 kfree_skb(skb);
3026out_unlock:
3027 if (dev)
3028 dev_put(dev);
3029out:
3030 return err;
3031}
3032
3033static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
3034{
3035 struct sock *sk = sock->sk;
3036 struct packet_sock *po = pkt_sk(sk);
3037
3038 /* Reading tx_ring.pg_vec without holding pg_vec_lock is racy.
3039 * tpacket_snd() will redo the check safely.
3040 */
3041 if (data_race(po->tx_ring.pg_vec))
3042 return tpacket_snd(po, msg);
3043
3044 return packet_snd(sock, msg, len);
3045}
3046
3047/*
3048 * Close a PACKET socket. This is fairly simple. We immediately go
3049 * to 'closed' state and remove our protocol entry in the device list.
3050 */
3051
3052static int packet_release(struct socket *sock)
3053{
3054 struct sock *sk = sock->sk;
3055 struct packet_sock *po;
3056 struct packet_fanout *f;
3057 struct net *net;
3058 union tpacket_req_u req_u;
3059
3060 if (!sk)
3061 return 0;
3062
3063 net = sock_net(sk);
3064 po = pkt_sk(sk);
3065
3066 mutex_lock(&net->packet.sklist_lock);
3067 sk_del_node_init_rcu(sk);
3068 mutex_unlock(&net->packet.sklist_lock);
3069
3070 preempt_disable();
3071 sock_prot_inuse_add(net, sk->sk_prot, -1);
3072 preempt_enable();
3073
3074 spin_lock(&po->bind_lock);
3075 unregister_prot_hook(sk, false);
3076 packet_cached_dev_reset(po);
3077
3078 if (po->prot_hook.dev) {
3079 dev_put(po->prot_hook.dev);
3080 po->prot_hook.dev = NULL;
3081 }
3082 spin_unlock(&po->bind_lock);
3083
3084 packet_flush_mclist(sk);
3085
3086 lock_sock(sk);
3087 if (po->rx_ring.pg_vec) {
3088 memset(&req_u, 0, sizeof(req_u));
3089 packet_set_ring(sk, &req_u, 1, 0);
3090 }
3091
3092 if (po->tx_ring.pg_vec) {
3093 memset(&req_u, 0, sizeof(req_u));
3094 packet_set_ring(sk, &req_u, 1, 1);
3095 }
3096 release_sock(sk);
3097
3098 f = fanout_release(sk);
3099
3100 synchronize_net();
3101
3102 kfree(po->rollover);
3103 if (f) {
3104 fanout_release_data(f);
3105 kvfree(f);
3106 }
3107 /*
3108 * Now the socket is dead. No more input will appear.
3109 */
3110 sock_orphan(sk);
3111 sock->sk = NULL;
3112
3113 /* Purge queues */
3114
3115 skb_queue_purge(&sk->sk_receive_queue);
3116 packet_free_pending(po);
3117 sk_refcnt_debug_release(sk);
3118
3119 sock_put(sk);
3120 return 0;
3121}
3122
3123/*
3124 * Attach a packet hook.
3125 */
3126
3127static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
3128 __be16 proto)
3129{
3130 struct packet_sock *po = pkt_sk(sk);
3131 struct net_device *dev_curr;
3132 __be16 proto_curr;
3133 bool need_rehook;
3134 struct net_device *dev = NULL;
3135 int ret = 0;
3136 bool unlisted = false;
3137
3138 lock_sock(sk);
3139 spin_lock(&po->bind_lock);
3140 rcu_read_lock();
3141
3142 if (po->fanout) {
3143 ret = -EINVAL;
3144 goto out_unlock;
3145 }
3146
3147 if (name) {
3148 dev = dev_get_by_name_rcu(sock_net(sk), name);
3149 if (!dev) {
3150 ret = -ENODEV;
3151 goto out_unlock;
3152 }
3153 } else if (ifindex) {
3154 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3155 if (!dev) {
3156 ret = -ENODEV;
3157 goto out_unlock;
3158 }
3159 }
3160
3161 if (dev)
3162 dev_hold(dev);
3163
3164 proto_curr = po->prot_hook.type;
3165 dev_curr = po->prot_hook.dev;
3166
3167 need_rehook = proto_curr != proto || dev_curr != dev;
3168
3169 if (need_rehook) {
3170 if (po->running) {
3171 rcu_read_unlock();
3172 /* prevents packet_notifier() from calling
3173 * register_prot_hook()
3174 */
3175 WRITE_ONCE(po->num, 0);
3176 __unregister_prot_hook(sk, true);
3177 rcu_read_lock();
3178 dev_curr = po->prot_hook.dev;
3179 if (dev)
3180 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3181 dev->ifindex);
3182 }
3183
3184 BUG_ON(po->running);
3185 WRITE_ONCE(po->num, proto);
3186 po->prot_hook.type = proto;
3187
3188 if (unlikely(unlisted)) {
3189 dev_put(dev);
3190 po->prot_hook.dev = NULL;
3191 WRITE_ONCE(po->ifindex, -1);
3192 packet_cached_dev_reset(po);
3193 } else {
3194 po->prot_hook.dev = dev;
3195 WRITE_ONCE(po->ifindex, dev ? dev->ifindex : 0);
3196 packet_cached_dev_assign(po, dev);
3197 }
3198 }
3199 if (dev_curr)
3200 dev_put(dev_curr);
3201
3202 if (proto == 0 || !need_rehook)
3203 goto out_unlock;
3204
3205 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3206 register_prot_hook(sk);
3207 } else {
3208 sk->sk_err = ENETDOWN;
3209 if (!sock_flag(sk, SOCK_DEAD))
3210 sk_error_report(sk);
3211 }
3212
3213out_unlock:
3214 rcu_read_unlock();
3215 spin_unlock(&po->bind_lock);
3216 release_sock(sk);
3217 return ret;
3218}
3219
3220/*
3221 * Bind a packet socket to a device
3222 */
3223
3224static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3225 int addr_len)
3226{
3227 struct sock *sk = sock->sk;
3228 char name[sizeof(uaddr->sa_data) + 1];
3229
3230 /*
3231 * Check legality
3232 */
3233
3234 if (addr_len != sizeof(struct sockaddr))
3235 return -EINVAL;
3236 /* uaddr->sa_data comes from the userspace, it's not guaranteed to be
3237 * zero-terminated.
3238 */
3239 memcpy(name, uaddr->sa_data, sizeof(uaddr->sa_data));
3240 name[sizeof(uaddr->sa_data)] = 0;
3241
3242 return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3243}
3244
3245static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3246{
3247 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3248 struct sock *sk = sock->sk;
3249
3250 /*
3251 * Check legality
3252 */
3253
3254 if (addr_len < sizeof(struct sockaddr_ll))
3255 return -EINVAL;
3256 if (sll->sll_family != AF_PACKET)
3257 return -EINVAL;
3258
3259 return packet_do_bind(sk, NULL, sll->sll_ifindex,
3260 sll->sll_protocol ? : pkt_sk(sk)->num);
3261}
3262
3263static struct proto packet_proto = {
3264 .name = "PACKET",
3265 .owner = THIS_MODULE,
3266 .obj_size = sizeof(struct packet_sock),
3267};
3268
3269/*
3270 * Create a packet of type SOCK_PACKET.
3271 */
3272
3273static int packet_create(struct net *net, struct socket *sock, int protocol,
3274 int kern)
3275{
3276 struct sock *sk;
3277 struct packet_sock *po;
3278 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3279 int err;
3280
3281 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3282 return -EPERM;
3283 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3284 sock->type != SOCK_PACKET)
3285 return -ESOCKTNOSUPPORT;
3286
3287 sock->state = SS_UNCONNECTED;
3288
3289 err = -ENOBUFS;
3290 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3291 if (sk == NULL)
3292 goto out;
3293
3294 sock->ops = &packet_ops;
3295 if (sock->type == SOCK_PACKET)
3296 sock->ops = &packet_ops_spkt;
3297
3298 sock_init_data(sock, sk);
3299
3300 po = pkt_sk(sk);
3301 init_completion(&po->skb_completion);
3302 sk->sk_family = PF_PACKET;
3303 po->num = proto;
3304 po->xmit = dev_queue_xmit;
3305
3306 err = packet_alloc_pending(po);
3307 if (err)
3308 goto out2;
3309
3310 packet_cached_dev_reset(po);
3311
3312 sk->sk_destruct = packet_sock_destruct;
3313 sk_refcnt_debug_inc(sk);
3314
3315 /*
3316 * Attach a protocol block
3317 */
3318
3319 spin_lock_init(&po->bind_lock);
3320 mutex_init(&po->pg_vec_lock);
3321 po->rollover = NULL;
3322 po->prot_hook.func = packet_rcv;
3323
3324 if (sock->type == SOCK_PACKET)
3325 po->prot_hook.func = packet_rcv_spkt;
3326
3327 po->prot_hook.af_packet_priv = sk;
3328
3329 if (proto) {
3330 po->prot_hook.type = proto;
3331 __register_prot_hook(sk);
3332 }
3333
3334 mutex_lock(&net->packet.sklist_lock);
3335 sk_add_node_tail_rcu(sk, &net->packet.sklist);
3336 mutex_unlock(&net->packet.sklist_lock);
3337
3338 preempt_disable();
3339 sock_prot_inuse_add(net, &packet_proto, 1);
3340 preempt_enable();
3341
3342 return 0;
3343out2:
3344 sk_free(sk);
3345out:
3346 return err;
3347}
3348
3349/*
3350 * Pull a packet from our receive queue and hand it to the user.
3351 * If necessary we block.
3352 */
3353
3354static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3355 int flags)
3356{
3357 struct sock *sk = sock->sk;
3358 struct sk_buff *skb;
3359 int copied, err;
3360 int vnet_hdr_len = 0;
3361 unsigned int origlen = 0;
3362
3363 err = -EINVAL;
3364 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3365 goto out;
3366
3367#if 0
3368 /* What error should we return now? EUNATTACH? */
3369 if (pkt_sk(sk)->ifindex < 0)
3370 return -ENODEV;
3371#endif
3372
3373 if (flags & MSG_ERRQUEUE) {
3374 err = sock_recv_errqueue(sk, msg, len,
3375 SOL_PACKET, PACKET_TX_TIMESTAMP);
3376 goto out;
3377 }
3378
3379 /*
3380 * Call the generic datagram receiver. This handles all sorts
3381 * of horrible races and re-entrancy so we can forget about it
3382 * in the protocol layers.
3383 *
3384 * Now it will return ENETDOWN, if device have just gone down,
3385 * but then it will block.
3386 */
3387
3388 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3389
3390 /*
3391 * An error occurred so return it. Because skb_recv_datagram()
3392 * handles the blocking we don't see and worry about blocking
3393 * retries.
3394 */
3395
3396 if (skb == NULL)
3397 goto out;
3398
3399 packet_rcv_try_clear_pressure(pkt_sk(sk));
3400
3401 if (pkt_sk(sk)->has_vnet_hdr) {
3402 err = packet_rcv_vnet(msg, skb, &len);
3403 if (err)
3404 goto out_free;
3405 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3406 }
3407
3408 /* You lose any data beyond the buffer you gave. If it worries
3409 * a user program they can ask the device for its MTU
3410 * anyway.
3411 */
3412 copied = skb->len;
3413 if (copied > len) {
3414 copied = len;
3415 msg->msg_flags |= MSG_TRUNC;
3416 }
3417
3418 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3419 if (err)
3420 goto out_free;
3421
3422 if (sock->type != SOCK_PACKET) {
3423 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3424
3425 /* Original length was stored in sockaddr_ll fields */
3426 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3427 sll->sll_family = AF_PACKET;
3428 sll->sll_protocol = skb->protocol;
3429 }
3430
3431 sock_recv_ts_and_drops(msg, sk, skb);
3432
3433 if (msg->msg_name) {
3434 int copy_len;
3435
3436 /* If the address length field is there to be filled
3437 * in, we fill it in now.
3438 */
3439 if (sock->type == SOCK_PACKET) {
3440 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3441 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3442 copy_len = msg->msg_namelen;
3443 } else {
3444 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3445
3446 msg->msg_namelen = sll->sll_halen +
3447 offsetof(struct sockaddr_ll, sll_addr);
3448 copy_len = msg->msg_namelen;
3449 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) {
3450 memset(msg->msg_name +
3451 offsetof(struct sockaddr_ll, sll_addr),
3452 0, sizeof(sll->sll_addr));
3453 msg->msg_namelen = sizeof(struct sockaddr_ll);
3454 }
3455 }
3456 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, copy_len);
3457 }
3458
3459 if (pkt_sk(sk)->auxdata) {
3460 struct tpacket_auxdata aux;
3461
3462 aux.tp_status = TP_STATUS_USER;
3463 if (skb->ip_summed == CHECKSUM_PARTIAL)
3464 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3465 else if (skb->pkt_type != PACKET_OUTGOING &&
3466 (skb->ip_summed == CHECKSUM_COMPLETE ||
3467 skb_csum_unnecessary(skb)))
3468 aux.tp_status |= TP_STATUS_CSUM_VALID;
3469
3470 aux.tp_len = origlen;
3471 aux.tp_snaplen = skb->len;
3472 aux.tp_mac = 0;
3473 aux.tp_net = skb_network_offset(skb);
3474 if (skb_vlan_tag_present(skb)) {
3475 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3476 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3477 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3478 } else {
3479 aux.tp_vlan_tci = 0;
3480 aux.tp_vlan_tpid = 0;
3481 }
3482 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3483 }
3484
3485 /*
3486 * Free or return the buffer as appropriate. Again this
3487 * hides all the races and re-entrancy issues from us.
3488 */
3489 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3490
3491out_free:
3492 skb_free_datagram(sk, skb);
3493out:
3494 return err;
3495}
3496
3497static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3498 int peer)
3499{
3500 struct net_device *dev;
3501 struct sock *sk = sock->sk;
3502
3503 if (peer)
3504 return -EOPNOTSUPP;
3505
3506 uaddr->sa_family = AF_PACKET;
3507 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3508 rcu_read_lock();
3509 dev = dev_get_by_index_rcu(sock_net(sk), READ_ONCE(pkt_sk(sk)->ifindex));
3510 if (dev)
3511 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3512 rcu_read_unlock();
3513
3514 return sizeof(*uaddr);
3515}
3516
3517static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3518 int peer)
3519{
3520 struct net_device *dev;
3521 struct sock *sk = sock->sk;
3522 struct packet_sock *po = pkt_sk(sk);
3523 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3524 int ifindex;
3525
3526 if (peer)
3527 return -EOPNOTSUPP;
3528
3529 ifindex = READ_ONCE(po->ifindex);
3530 sll->sll_family = AF_PACKET;
3531 sll->sll_ifindex = ifindex;
3532 sll->sll_protocol = READ_ONCE(po->num);
3533 sll->sll_pkttype = 0;
3534 rcu_read_lock();
3535 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3536 if (dev) {
3537 sll->sll_hatype = dev->type;
3538 sll->sll_halen = dev->addr_len;
3539 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3540 } else {
3541 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3542 sll->sll_halen = 0;
3543 }
3544 rcu_read_unlock();
3545
3546 return offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3547}
3548
3549static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3550 int what)
3551{
3552 switch (i->type) {
3553 case PACKET_MR_MULTICAST:
3554 if (i->alen != dev->addr_len)
3555 return -EINVAL;
3556 if (what > 0)
3557 return dev_mc_add(dev, i->addr);
3558 else
3559 return dev_mc_del(dev, i->addr);
3560 break;
3561 case PACKET_MR_PROMISC:
3562 return dev_set_promiscuity(dev, what);
3563 case PACKET_MR_ALLMULTI:
3564 return dev_set_allmulti(dev, what);
3565 case PACKET_MR_UNICAST:
3566 if (i->alen != dev->addr_len)
3567 return -EINVAL;
3568 if (what > 0)
3569 return dev_uc_add(dev, i->addr);
3570 else
3571 return dev_uc_del(dev, i->addr);
3572 break;
3573 default:
3574 break;
3575 }
3576 return 0;
3577}
3578
3579static void packet_dev_mclist_delete(struct net_device *dev,
3580 struct packet_mclist **mlp)
3581{
3582 struct packet_mclist *ml;
3583
3584 while ((ml = *mlp) != NULL) {
3585 if (ml->ifindex == dev->ifindex) {
3586 packet_dev_mc(dev, ml, -1);
3587 *mlp = ml->next;
3588 kfree(ml);
3589 } else
3590 mlp = &ml->next;
3591 }
3592}
3593
3594static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3595{
3596 struct packet_sock *po = pkt_sk(sk);
3597 struct packet_mclist *ml, *i;
3598 struct net_device *dev;
3599 int err;
3600
3601 rtnl_lock();
3602
3603 err = -ENODEV;
3604 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3605 if (!dev)
3606 goto done;
3607
3608 err = -EINVAL;
3609 if (mreq->mr_alen > dev->addr_len)
3610 goto done;
3611
3612 err = -ENOBUFS;
3613 i = kmalloc(sizeof(*i), GFP_KERNEL);
3614 if (i == NULL)
3615 goto done;
3616
3617 err = 0;
3618 for (ml = po->mclist; ml; ml = ml->next) {
3619 if (ml->ifindex == mreq->mr_ifindex &&
3620 ml->type == mreq->mr_type &&
3621 ml->alen == mreq->mr_alen &&
3622 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3623 ml->count++;
3624 /* Free the new element ... */
3625 kfree(i);
3626 goto done;
3627 }
3628 }
3629
3630 i->type = mreq->mr_type;
3631 i->ifindex = mreq->mr_ifindex;
3632 i->alen = mreq->mr_alen;
3633 memcpy(i->addr, mreq->mr_address, i->alen);
3634 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3635 i->count = 1;
3636 i->next = po->mclist;
3637 po->mclist = i;
3638 err = packet_dev_mc(dev, i, 1);
3639 if (err) {
3640 po->mclist = i->next;
3641 kfree(i);
3642 }
3643
3644done:
3645 rtnl_unlock();
3646 return err;
3647}
3648
3649static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3650{
3651 struct packet_mclist *ml, **mlp;
3652
3653 rtnl_lock();
3654
3655 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3656 if (ml->ifindex == mreq->mr_ifindex &&
3657 ml->type == mreq->mr_type &&
3658 ml->alen == mreq->mr_alen &&
3659 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3660 if (--ml->count == 0) {
3661 struct net_device *dev;
3662 *mlp = ml->next;
3663 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3664 if (dev)
3665 packet_dev_mc(dev, ml, -1);
3666 kfree(ml);
3667 }
3668 break;
3669 }
3670 }
3671 rtnl_unlock();
3672 return 0;
3673}
3674
3675static void packet_flush_mclist(struct sock *sk)
3676{
3677 struct packet_sock *po = pkt_sk(sk);
3678 struct packet_mclist *ml;
3679
3680 if (!po->mclist)
3681 return;
3682
3683 rtnl_lock();
3684 while ((ml = po->mclist) != NULL) {
3685 struct net_device *dev;
3686
3687 po->mclist = ml->next;
3688 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3689 if (dev != NULL)
3690 packet_dev_mc(dev, ml, -1);
3691 kfree(ml);
3692 }
3693 rtnl_unlock();
3694}
3695
3696static int
3697packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval,
3698 unsigned int optlen)
3699{
3700 struct sock *sk = sock->sk;
3701 struct packet_sock *po = pkt_sk(sk);
3702 int ret;
3703
3704 if (level != SOL_PACKET)
3705 return -ENOPROTOOPT;
3706
3707 switch (optname) {
3708 case PACKET_ADD_MEMBERSHIP:
3709 case PACKET_DROP_MEMBERSHIP:
3710 {
3711 struct packet_mreq_max mreq;
3712 int len = optlen;
3713 memset(&mreq, 0, sizeof(mreq));
3714 if (len < sizeof(struct packet_mreq))
3715 return -EINVAL;
3716 if (len > sizeof(mreq))
3717 len = sizeof(mreq);
3718 if (copy_from_sockptr(&mreq, optval, len))
3719 return -EFAULT;
3720 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3721 return -EINVAL;
3722 if (optname == PACKET_ADD_MEMBERSHIP)
3723 ret = packet_mc_add(sk, &mreq);
3724 else
3725 ret = packet_mc_drop(sk, &mreq);
3726 return ret;
3727 }
3728
3729 case PACKET_RX_RING:
3730 case PACKET_TX_RING:
3731 {
3732 union tpacket_req_u req_u;
3733 int len;
3734
3735 lock_sock(sk);
3736 switch (po->tp_version) {
3737 case TPACKET_V1:
3738 case TPACKET_V2:
3739 len = sizeof(req_u.req);
3740 break;
3741 case TPACKET_V3:
3742 default:
3743 len = sizeof(req_u.req3);
3744 break;
3745 }
3746 if (optlen < len) {
3747 ret = -EINVAL;
3748 } else {
3749 if (copy_from_sockptr(&req_u.req, optval, len))
3750 ret = -EFAULT;
3751 else
3752 ret = packet_set_ring(sk, &req_u, 0,
3753 optname == PACKET_TX_RING);
3754 }
3755 release_sock(sk);
3756 return ret;
3757 }
3758 case PACKET_COPY_THRESH:
3759 {
3760 int val;
3761
3762 if (optlen != sizeof(val))
3763 return -EINVAL;
3764 if (copy_from_sockptr(&val, optval, sizeof(val)))
3765 return -EFAULT;
3766
3767 pkt_sk(sk)->copy_thresh = val;
3768 return 0;
3769 }
3770 case PACKET_VERSION:
3771 {
3772 int val;
3773
3774 if (optlen != sizeof(val))
3775 return -EINVAL;
3776 if (copy_from_sockptr(&val, optval, sizeof(val)))
3777 return -EFAULT;
3778 switch (val) {
3779 case TPACKET_V1:
3780 case TPACKET_V2:
3781 case TPACKET_V3:
3782 break;
3783 default:
3784 return -EINVAL;
3785 }
3786 lock_sock(sk);
3787 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3788 ret = -EBUSY;
3789 } else {
3790 po->tp_version = val;
3791 ret = 0;
3792 }
3793 release_sock(sk);
3794 return ret;
3795 }
3796 case PACKET_RESERVE:
3797 {
3798 unsigned int val;
3799
3800 if (optlen != sizeof(val))
3801 return -EINVAL;
3802 if (copy_from_sockptr(&val, optval, sizeof(val)))
3803 return -EFAULT;
3804 if (val > INT_MAX)
3805 return -EINVAL;
3806 lock_sock(sk);
3807 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3808 ret = -EBUSY;
3809 } else {
3810 po->tp_reserve = val;
3811 ret = 0;
3812 }
3813 release_sock(sk);
3814 return ret;
3815 }
3816 case PACKET_LOSS:
3817 {
3818 unsigned int val;
3819
3820 if (optlen != sizeof(val))
3821 return -EINVAL;
3822 if (copy_from_sockptr(&val, optval, sizeof(val)))
3823 return -EFAULT;
3824
3825 lock_sock(sk);
3826 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3827 ret = -EBUSY;
3828 } else {
3829 po->tp_loss = !!val;
3830 ret = 0;
3831 }
3832 release_sock(sk);
3833 return ret;
3834 }
3835 case PACKET_AUXDATA:
3836 {
3837 int val;
3838
3839 if (optlen < sizeof(val))
3840 return -EINVAL;
3841 if (copy_from_sockptr(&val, optval, sizeof(val)))
3842 return -EFAULT;
3843
3844 lock_sock(sk);
3845 po->auxdata = !!val;
3846 release_sock(sk);
3847 return 0;
3848 }
3849 case PACKET_ORIGDEV:
3850 {
3851 int val;
3852
3853 if (optlen < sizeof(val))
3854 return -EINVAL;
3855 if (copy_from_sockptr(&val, optval, sizeof(val)))
3856 return -EFAULT;
3857
3858 lock_sock(sk);
3859 po->origdev = !!val;
3860 release_sock(sk);
3861 return 0;
3862 }
3863 case PACKET_VNET_HDR:
3864 {
3865 int val;
3866
3867 if (sock->type != SOCK_RAW)
3868 return -EINVAL;
3869 if (optlen < sizeof(val))
3870 return -EINVAL;
3871 if (copy_from_sockptr(&val, optval, sizeof(val)))
3872 return -EFAULT;
3873
3874 lock_sock(sk);
3875 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3876 ret = -EBUSY;
3877 } else {
3878 po->has_vnet_hdr = !!val;
3879 ret = 0;
3880 }
3881 release_sock(sk);
3882 return ret;
3883 }
3884 case PACKET_TIMESTAMP:
3885 {
3886 int val;
3887
3888 if (optlen != sizeof(val))
3889 return -EINVAL;
3890 if (copy_from_sockptr(&val, optval, sizeof(val)))
3891 return -EFAULT;
3892
3893 po->tp_tstamp = val;
3894 return 0;
3895 }
3896 case PACKET_FANOUT:
3897 {
3898 struct fanout_args args = { 0 };
3899
3900 if (optlen != sizeof(int) && optlen != sizeof(args))
3901 return -EINVAL;
3902 if (copy_from_sockptr(&args, optval, optlen))
3903 return -EFAULT;
3904
3905 return fanout_add(sk, &args);
3906 }
3907 case PACKET_FANOUT_DATA:
3908 {
3909 if (!po->fanout)
3910 return -EINVAL;
3911
3912 return fanout_set_data(po, optval, optlen);
3913 }
3914 case PACKET_IGNORE_OUTGOING:
3915 {
3916 int val;
3917
3918 if (optlen != sizeof(val))
3919 return -EINVAL;
3920 if (copy_from_sockptr(&val, optval, sizeof(val)))
3921 return -EFAULT;
3922 if (val < 0 || val > 1)
3923 return -EINVAL;
3924
3925 po->prot_hook.ignore_outgoing = !!val;
3926 return 0;
3927 }
3928 case PACKET_TX_HAS_OFF:
3929 {
3930 unsigned int val;
3931
3932 if (optlen != sizeof(val))
3933 return -EINVAL;
3934 if (copy_from_sockptr(&val, optval, sizeof(val)))
3935 return -EFAULT;
3936
3937 lock_sock(sk);
3938 if (!po->rx_ring.pg_vec && !po->tx_ring.pg_vec)
3939 po->tp_tx_has_off = !!val;
3940
3941 release_sock(sk);
3942 return 0;
3943 }
3944 case PACKET_QDISC_BYPASS:
3945 {
3946 int val;
3947
3948 if (optlen != sizeof(val))
3949 return -EINVAL;
3950 if (copy_from_sockptr(&val, optval, sizeof(val)))
3951 return -EFAULT;
3952
3953 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3954 return 0;
3955 }
3956 default:
3957 return -ENOPROTOOPT;
3958 }
3959}
3960
3961static int packet_getsockopt(struct socket *sock, int level, int optname,
3962 char __user *optval, int __user *optlen)
3963{
3964 int len;
3965 int val, lv = sizeof(val);
3966 struct sock *sk = sock->sk;
3967 struct packet_sock *po = pkt_sk(sk);
3968 void *data = &val;
3969 union tpacket_stats_u st;
3970 struct tpacket_rollover_stats rstats;
3971 int drops;
3972
3973 if (level != SOL_PACKET)
3974 return -ENOPROTOOPT;
3975
3976 if (get_user(len, optlen))
3977 return -EFAULT;
3978
3979 if (len < 0)
3980 return -EINVAL;
3981
3982 switch (optname) {
3983 case PACKET_STATISTICS:
3984 spin_lock_bh(&sk->sk_receive_queue.lock);
3985 memcpy(&st, &po->stats, sizeof(st));
3986 memset(&po->stats, 0, sizeof(po->stats));
3987 spin_unlock_bh(&sk->sk_receive_queue.lock);
3988 drops = atomic_xchg(&po->tp_drops, 0);
3989
3990 if (po->tp_version == TPACKET_V3) {
3991 lv = sizeof(struct tpacket_stats_v3);
3992 st.stats3.tp_drops = drops;
3993 st.stats3.tp_packets += drops;
3994 data = &st.stats3;
3995 } else {
3996 lv = sizeof(struct tpacket_stats);
3997 st.stats1.tp_drops = drops;
3998 st.stats1.tp_packets += drops;
3999 data = &st.stats1;
4000 }
4001
4002 break;
4003 case PACKET_AUXDATA:
4004 val = po->auxdata;
4005 break;
4006 case PACKET_ORIGDEV:
4007 val = po->origdev;
4008 break;
4009 case PACKET_VNET_HDR:
4010 val = po->has_vnet_hdr;
4011 break;
4012 case PACKET_VERSION:
4013 val = po->tp_version;
4014 break;
4015 case PACKET_HDRLEN:
4016 if (len > sizeof(int))
4017 len = sizeof(int);
4018 if (len < sizeof(int))
4019 return -EINVAL;
4020 if (copy_from_user(&val, optval, len))
4021 return -EFAULT;
4022 switch (val) {
4023 case TPACKET_V1:
4024 val = sizeof(struct tpacket_hdr);
4025 break;
4026 case TPACKET_V2:
4027 val = sizeof(struct tpacket2_hdr);
4028 break;
4029 case TPACKET_V3:
4030 val = sizeof(struct tpacket3_hdr);
4031 break;
4032 default:
4033 return -EINVAL;
4034 }
4035 break;
4036 case PACKET_RESERVE:
4037 val = po->tp_reserve;
4038 break;
4039 case PACKET_LOSS:
4040 val = po->tp_loss;
4041 break;
4042 case PACKET_TIMESTAMP:
4043 val = po->tp_tstamp;
4044 break;
4045 case PACKET_FANOUT:
4046 val = (po->fanout ?
4047 ((u32)po->fanout->id |
4048 ((u32)po->fanout->type << 16) |
4049 ((u32)po->fanout->flags << 24)) :
4050 0);
4051 break;
4052 case PACKET_IGNORE_OUTGOING:
4053 val = po->prot_hook.ignore_outgoing;
4054 break;
4055 case PACKET_ROLLOVER_STATS:
4056 if (!po->rollover)
4057 return -EINVAL;
4058 rstats.tp_all = atomic_long_read(&po->rollover->num);
4059 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
4060 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
4061 data = &rstats;
4062 lv = sizeof(rstats);
4063 break;
4064 case PACKET_TX_HAS_OFF:
4065 val = po->tp_tx_has_off;
4066 break;
4067 case PACKET_QDISC_BYPASS:
4068 val = packet_use_direct_xmit(po);
4069 break;
4070 default:
4071 return -ENOPROTOOPT;
4072 }
4073
4074 if (len > lv)
4075 len = lv;
4076 if (put_user(len, optlen))
4077 return -EFAULT;
4078 if (copy_to_user(optval, data, len))
4079 return -EFAULT;
4080 return 0;
4081}
4082
4083static int packet_notifier(struct notifier_block *this,
4084 unsigned long msg, void *ptr)
4085{
4086 struct sock *sk;
4087 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
4088 struct net *net = dev_net(dev);
4089
4090 rcu_read_lock();
4091 sk_for_each_rcu(sk, &net->packet.sklist) {
4092 struct packet_sock *po = pkt_sk(sk);
4093
4094 switch (msg) {
4095 case NETDEV_UNREGISTER:
4096 if (po->mclist)
4097 packet_dev_mclist_delete(dev, &po->mclist);
4098 fallthrough;
4099
4100 case NETDEV_DOWN:
4101 if (dev->ifindex == po->ifindex) {
4102 spin_lock(&po->bind_lock);
4103 if (po->running) {
4104 __unregister_prot_hook(sk, false);
4105 sk->sk_err = ENETDOWN;
4106 if (!sock_flag(sk, SOCK_DEAD))
4107 sk_error_report(sk);
4108 }
4109 if (msg == NETDEV_UNREGISTER) {
4110 packet_cached_dev_reset(po);
4111 WRITE_ONCE(po->ifindex, -1);
4112 if (po->prot_hook.dev)
4113 dev_put(po->prot_hook.dev);
4114 po->prot_hook.dev = NULL;
4115 }
4116 spin_unlock(&po->bind_lock);
4117 }
4118 break;
4119 case NETDEV_UP:
4120 if (dev->ifindex == po->ifindex) {
4121 spin_lock(&po->bind_lock);
4122 if (po->num)
4123 register_prot_hook(sk);
4124 spin_unlock(&po->bind_lock);
4125 }
4126 break;
4127 }
4128 }
4129 rcu_read_unlock();
4130 return NOTIFY_DONE;
4131}
4132
4133
4134static int packet_ioctl(struct socket *sock, unsigned int cmd,
4135 unsigned long arg)
4136{
4137 struct sock *sk = sock->sk;
4138
4139 switch (cmd) {
4140 case SIOCOUTQ:
4141 {
4142 int amount = sk_wmem_alloc_get(sk);
4143
4144 return put_user(amount, (int __user *)arg);
4145 }
4146 case SIOCINQ:
4147 {
4148 struct sk_buff *skb;
4149 int amount = 0;
4150
4151 spin_lock_bh(&sk->sk_receive_queue.lock);
4152 skb = skb_peek(&sk->sk_receive_queue);
4153 if (skb)
4154 amount = skb->len;
4155 spin_unlock_bh(&sk->sk_receive_queue.lock);
4156 return put_user(amount, (int __user *)arg);
4157 }
4158#ifdef CONFIG_INET
4159 case SIOCADDRT:
4160 case SIOCDELRT:
4161 case SIOCDARP:
4162 case SIOCGARP:
4163 case SIOCSARP:
4164 case SIOCGIFADDR:
4165 case SIOCSIFADDR:
4166 case SIOCGIFBRDADDR:
4167 case SIOCSIFBRDADDR:
4168 case SIOCGIFNETMASK:
4169 case SIOCSIFNETMASK:
4170 case SIOCGIFDSTADDR:
4171 case SIOCSIFDSTADDR:
4172 case SIOCSIFFLAGS:
4173 return inet_dgram_ops.ioctl(sock, cmd, arg);
4174#endif
4175
4176 default:
4177 return -ENOIOCTLCMD;
4178 }
4179 return 0;
4180}
4181
4182static __poll_t packet_poll(struct file *file, struct socket *sock,
4183 poll_table *wait)
4184{
4185 struct sock *sk = sock->sk;
4186 struct packet_sock *po = pkt_sk(sk);
4187 __poll_t mask = datagram_poll(file, sock, wait);
4188
4189 spin_lock_bh(&sk->sk_receive_queue.lock);
4190 if (po->rx_ring.pg_vec) {
4191 if (!packet_previous_rx_frame(po, &po->rx_ring,
4192 TP_STATUS_KERNEL))
4193 mask |= EPOLLIN | EPOLLRDNORM;
4194 }
4195 packet_rcv_try_clear_pressure(po);
4196 spin_unlock_bh(&sk->sk_receive_queue.lock);
4197 spin_lock_bh(&sk->sk_write_queue.lock);
4198 if (po->tx_ring.pg_vec) {
4199 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4200 mask |= EPOLLOUT | EPOLLWRNORM;
4201 }
4202 spin_unlock_bh(&sk->sk_write_queue.lock);
4203 return mask;
4204}
4205
4206
4207/* Dirty? Well, I still did not learn better way to account
4208 * for user mmaps.
4209 */
4210
4211static void packet_mm_open(struct vm_area_struct *vma)
4212{
4213 struct file *file = vma->vm_file;
4214 struct socket *sock = file->private_data;
4215 struct sock *sk = sock->sk;
4216
4217 if (sk)
4218 atomic_inc(&pkt_sk(sk)->mapped);
4219}
4220
4221static void packet_mm_close(struct vm_area_struct *vma)
4222{
4223 struct file *file = vma->vm_file;
4224 struct socket *sock = file->private_data;
4225 struct sock *sk = sock->sk;
4226
4227 if (sk)
4228 atomic_dec(&pkt_sk(sk)->mapped);
4229}
4230
4231static const struct vm_operations_struct packet_mmap_ops = {
4232 .open = packet_mm_open,
4233 .close = packet_mm_close,
4234};
4235
4236static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4237 unsigned int len)
4238{
4239 int i;
4240
4241 for (i = 0; i < len; i++) {
4242 if (likely(pg_vec[i].buffer)) {
4243 if (is_vmalloc_addr(pg_vec[i].buffer))
4244 vfree(pg_vec[i].buffer);
4245 else
4246 free_pages((unsigned long)pg_vec[i].buffer,
4247 order);
4248 pg_vec[i].buffer = NULL;
4249 }
4250 }
4251 kfree(pg_vec);
4252}
4253
4254static char *alloc_one_pg_vec_page(unsigned long order)
4255{
4256 char *buffer;
4257 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4258 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4259
4260 buffer = (char *) __get_free_pages(gfp_flags, order);
4261 if (buffer)
4262 return buffer;
4263
4264 /* __get_free_pages failed, fall back to vmalloc */
4265 buffer = vzalloc(array_size((1 << order), PAGE_SIZE));
4266 if (buffer)
4267 return buffer;
4268
4269 /* vmalloc failed, lets dig into swap here */
4270 gfp_flags &= ~__GFP_NORETRY;
4271 buffer = (char *) __get_free_pages(gfp_flags, order);
4272 if (buffer)
4273 return buffer;
4274
4275 /* complete and utter failure */
4276 return NULL;
4277}
4278
4279static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4280{
4281 unsigned int block_nr = req->tp_block_nr;
4282 struct pgv *pg_vec;
4283 int i;
4284
4285 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL | __GFP_NOWARN);
4286 if (unlikely(!pg_vec))
4287 goto out;
4288
4289 for (i = 0; i < block_nr; i++) {
4290 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4291 if (unlikely(!pg_vec[i].buffer))
4292 goto out_free_pgvec;
4293 }
4294
4295out:
4296 return pg_vec;
4297
4298out_free_pgvec:
4299 free_pg_vec(pg_vec, order, block_nr);
4300 pg_vec = NULL;
4301 goto out;
4302}
4303
4304static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4305 int closing, int tx_ring)
4306{
4307 struct pgv *pg_vec = NULL;
4308 struct packet_sock *po = pkt_sk(sk);
4309 unsigned long *rx_owner_map = NULL;
4310 int was_running, order = 0;
4311 struct packet_ring_buffer *rb;
4312 struct sk_buff_head *rb_queue;
4313 __be16 num;
4314 int err;
4315 /* Added to avoid minimal code churn */
4316 struct tpacket_req *req = &req_u->req;
4317
4318 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4319 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4320
4321 err = -EBUSY;
4322 if (!closing) {
4323 if (atomic_read(&po->mapped))
4324 goto out;
4325 if (packet_read_pending(rb))
4326 goto out;
4327 }
4328
4329 if (req->tp_block_nr) {
4330 unsigned int min_frame_size;
4331
4332 /* Sanity tests and some calculations */
4333 err = -EBUSY;
4334 if (unlikely(rb->pg_vec))
4335 goto out;
4336
4337 switch (po->tp_version) {
4338 case TPACKET_V1:
4339 po->tp_hdrlen = TPACKET_HDRLEN;
4340 break;
4341 case TPACKET_V2:
4342 po->tp_hdrlen = TPACKET2_HDRLEN;
4343 break;
4344 case TPACKET_V3:
4345 po->tp_hdrlen = TPACKET3_HDRLEN;
4346 break;
4347 }
4348
4349 err = -EINVAL;
4350 if (unlikely((int)req->tp_block_size <= 0))
4351 goto out;
4352 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4353 goto out;
4354 min_frame_size = po->tp_hdrlen + po->tp_reserve;
4355 if (po->tp_version >= TPACKET_V3 &&
4356 req->tp_block_size <
4357 BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv) + min_frame_size)
4358 goto out;
4359 if (unlikely(req->tp_frame_size < min_frame_size))
4360 goto out;
4361 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4362 goto out;
4363
4364 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4365 if (unlikely(rb->frames_per_block == 0))
4366 goto out;
4367 if (unlikely(rb->frames_per_block > UINT_MAX / req->tp_block_nr))
4368 goto out;
4369 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4370 req->tp_frame_nr))
4371 goto out;
4372
4373 err = -ENOMEM;
4374 order = get_order(req->tp_block_size);
4375 pg_vec = alloc_pg_vec(req, order);
4376 if (unlikely(!pg_vec))
4377 goto out;
4378 switch (po->tp_version) {
4379 case TPACKET_V3:
4380 /* Block transmit is not supported yet */
4381 if (!tx_ring) {
4382 init_prb_bdqc(po, rb, pg_vec, req_u);
4383 } else {
4384 struct tpacket_req3 *req3 = &req_u->req3;
4385
4386 if (req3->tp_retire_blk_tov ||
4387 req3->tp_sizeof_priv ||
4388 req3->tp_feature_req_word) {
4389 err = -EINVAL;
4390 goto out_free_pg_vec;
4391 }
4392 }
4393 break;
4394 default:
4395 if (!tx_ring) {
4396 rx_owner_map = bitmap_alloc(req->tp_frame_nr,
4397 GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO);
4398 if (!rx_owner_map)
4399 goto out_free_pg_vec;
4400 }
4401 break;
4402 }
4403 }
4404 /* Done */
4405 else {
4406 err = -EINVAL;
4407 if (unlikely(req->tp_frame_nr))
4408 goto out;
4409 }
4410
4411
4412 /* Detach socket from network */
4413 spin_lock(&po->bind_lock);
4414 was_running = po->running;
4415 num = po->num;
4416 if (was_running) {
4417 WRITE_ONCE(po->num, 0);
4418 __unregister_prot_hook(sk, false);
4419 }
4420 spin_unlock(&po->bind_lock);
4421
4422 synchronize_net();
4423
4424 err = -EBUSY;
4425 mutex_lock(&po->pg_vec_lock);
4426 if (closing || atomic_read(&po->mapped) == 0) {
4427 err = 0;
4428 spin_lock_bh(&rb_queue->lock);
4429 swap(rb->pg_vec, pg_vec);
4430 if (po->tp_version <= TPACKET_V2)
4431 swap(rb->rx_owner_map, rx_owner_map);
4432 rb->frame_max = (req->tp_frame_nr - 1);
4433 rb->head = 0;
4434 rb->frame_size = req->tp_frame_size;
4435 spin_unlock_bh(&rb_queue->lock);
4436
4437 swap(rb->pg_vec_order, order);
4438 swap(rb->pg_vec_len, req->tp_block_nr);
4439
4440 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4441 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4442 tpacket_rcv : packet_rcv;
4443 skb_queue_purge(rb_queue);
4444 if (atomic_read(&po->mapped))
4445 pr_err("packet_mmap: vma is busy: %d\n",
4446 atomic_read(&po->mapped));
4447 }
4448 mutex_unlock(&po->pg_vec_lock);
4449
4450 spin_lock(&po->bind_lock);
4451 if (was_running) {
4452 WRITE_ONCE(po->num, num);
4453 register_prot_hook(sk);
4454 }
4455 spin_unlock(&po->bind_lock);
4456 if (pg_vec && (po->tp_version > TPACKET_V2)) {
4457 /* Because we don't support block-based V3 on tx-ring */
4458 if (!tx_ring)
4459 prb_shutdown_retire_blk_timer(po, rb_queue);
4460 }
4461
4462out_free_pg_vec:
4463 bitmap_free(rx_owner_map);
4464 if (pg_vec)
4465 free_pg_vec(pg_vec, order, req->tp_block_nr);
4466out:
4467 return err;
4468}
4469
4470static int packet_mmap(struct file *file, struct socket *sock,
4471 struct vm_area_struct *vma)
4472{
4473 struct sock *sk = sock->sk;
4474 struct packet_sock *po = pkt_sk(sk);
4475 unsigned long size, expected_size;
4476 struct packet_ring_buffer *rb;
4477 unsigned long start;
4478 int err = -EINVAL;
4479 int i;
4480
4481 if (vma->vm_pgoff)
4482 return -EINVAL;
4483
4484 mutex_lock(&po->pg_vec_lock);
4485
4486 expected_size = 0;
4487 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4488 if (rb->pg_vec) {
4489 expected_size += rb->pg_vec_len
4490 * rb->pg_vec_pages
4491 * PAGE_SIZE;
4492 }
4493 }
4494
4495 if (expected_size == 0)
4496 goto out;
4497
4498 size = vma->vm_end - vma->vm_start;
4499 if (size != expected_size)
4500 goto out;
4501
4502 start = vma->vm_start;
4503 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4504 if (rb->pg_vec == NULL)
4505 continue;
4506
4507 for (i = 0; i < rb->pg_vec_len; i++) {
4508 struct page *page;
4509 void *kaddr = rb->pg_vec[i].buffer;
4510 int pg_num;
4511
4512 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4513 page = pgv_to_page(kaddr);
4514 err = vm_insert_page(vma, start, page);
4515 if (unlikely(err))
4516 goto out;
4517 start += PAGE_SIZE;
4518 kaddr += PAGE_SIZE;
4519 }
4520 }
4521 }
4522
4523 atomic_inc(&po->mapped);
4524 vma->vm_ops = &packet_mmap_ops;
4525 err = 0;
4526
4527out:
4528 mutex_unlock(&po->pg_vec_lock);
4529 return err;
4530}
4531
4532static const struct proto_ops packet_ops_spkt = {
4533 .family = PF_PACKET,
4534 .owner = THIS_MODULE,
4535 .release = packet_release,
4536 .bind = packet_bind_spkt,
4537 .connect = sock_no_connect,
4538 .socketpair = sock_no_socketpair,
4539 .accept = sock_no_accept,
4540 .getname = packet_getname_spkt,
4541 .poll = datagram_poll,
4542 .ioctl = packet_ioctl,
4543 .gettstamp = sock_gettstamp,
4544 .listen = sock_no_listen,
4545 .shutdown = sock_no_shutdown,
4546 .sendmsg = packet_sendmsg_spkt,
4547 .recvmsg = packet_recvmsg,
4548 .mmap = sock_no_mmap,
4549 .sendpage = sock_no_sendpage,
4550};
4551
4552static const struct proto_ops packet_ops = {
4553 .family = PF_PACKET,
4554 .owner = THIS_MODULE,
4555 .release = packet_release,
4556 .bind = packet_bind,
4557 .connect = sock_no_connect,
4558 .socketpair = sock_no_socketpair,
4559 .accept = sock_no_accept,
4560 .getname = packet_getname,
4561 .poll = packet_poll,
4562 .ioctl = packet_ioctl,
4563 .gettstamp = sock_gettstamp,
4564 .listen = sock_no_listen,
4565 .shutdown = sock_no_shutdown,
4566 .setsockopt = packet_setsockopt,
4567 .getsockopt = packet_getsockopt,
4568 .sendmsg = packet_sendmsg,
4569 .recvmsg = packet_recvmsg,
4570 .mmap = packet_mmap,
4571 .sendpage = sock_no_sendpage,
4572};
4573
4574static const struct net_proto_family packet_family_ops = {
4575 .family = PF_PACKET,
4576 .create = packet_create,
4577 .owner = THIS_MODULE,
4578};
4579
4580static struct notifier_block packet_netdev_notifier = {
4581 .notifier_call = packet_notifier,
4582};
4583
4584#ifdef CONFIG_PROC_FS
4585
4586static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4587 __acquires(RCU)
4588{
4589 struct net *net = seq_file_net(seq);
4590
4591 rcu_read_lock();
4592 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4593}
4594
4595static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4596{
4597 struct net *net = seq_file_net(seq);
4598 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4599}
4600
4601static void packet_seq_stop(struct seq_file *seq, void *v)
4602 __releases(RCU)
4603{
4604 rcu_read_unlock();
4605}
4606
4607static int packet_seq_show(struct seq_file *seq, void *v)
4608{
4609 if (v == SEQ_START_TOKEN)
4610 seq_printf(seq,
4611 "%*sRefCnt Type Proto Iface R Rmem User Inode\n",
4612 IS_ENABLED(CONFIG_64BIT) ? -17 : -9, "sk");
4613 else {
4614 struct sock *s = sk_entry(v);
4615 const struct packet_sock *po = pkt_sk(s);
4616
4617 seq_printf(seq,
4618 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4619 s,
4620 refcount_read(&s->sk_refcnt),
4621 s->sk_type,
4622 ntohs(READ_ONCE(po->num)),
4623 READ_ONCE(po->ifindex),
4624 po->running,
4625 atomic_read(&s->sk_rmem_alloc),
4626 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4627 sock_i_ino(s));
4628 }
4629
4630 return 0;
4631}
4632
4633static const struct seq_operations packet_seq_ops = {
4634 .start = packet_seq_start,
4635 .next = packet_seq_next,
4636 .stop = packet_seq_stop,
4637 .show = packet_seq_show,
4638};
4639#endif
4640
4641static int __net_init packet_net_init(struct net *net)
4642{
4643 mutex_init(&net->packet.sklist_lock);
4644 INIT_HLIST_HEAD(&net->packet.sklist);
4645
4646#ifdef CONFIG_PROC_FS
4647 if (!proc_create_net("packet", 0, net->proc_net, &packet_seq_ops,
4648 sizeof(struct seq_net_private)))
4649 return -ENOMEM;
4650#endif /* CONFIG_PROC_FS */
4651
4652 return 0;
4653}
4654
4655static void __net_exit packet_net_exit(struct net *net)
4656{
4657 remove_proc_entry("packet", net->proc_net);
4658 WARN_ON_ONCE(!hlist_empty(&net->packet.sklist));
4659}
4660
4661static struct pernet_operations packet_net_ops = {
4662 .init = packet_net_init,
4663 .exit = packet_net_exit,
4664};
4665
4666
4667static void __exit packet_exit(void)
4668{
4669 unregister_netdevice_notifier(&packet_netdev_notifier);
4670 unregister_pernet_subsys(&packet_net_ops);
4671 sock_unregister(PF_PACKET);
4672 proto_unregister(&packet_proto);
4673}
4674
4675static int __init packet_init(void)
4676{
4677 int rc;
4678
4679 rc = proto_register(&packet_proto, 0);
4680 if (rc)
4681 goto out;
4682 rc = sock_register(&packet_family_ops);
4683 if (rc)
4684 goto out_proto;
4685 rc = register_pernet_subsys(&packet_net_ops);
4686 if (rc)
4687 goto out_sock;
4688 rc = register_netdevice_notifier(&packet_netdev_notifier);
4689 if (rc)
4690 goto out_pernet;
4691
4692 return 0;
4693
4694out_pernet:
4695 unregister_pernet_subsys(&packet_net_ops);
4696out_sock:
4697 sock_unregister(PF_PACKET);
4698out_proto:
4699 proto_unregister(&packet_proto);
4700out:
4701 return rc;
4702}
4703
4704module_init(packet_init);
4705module_exit(packet_exit);
4706MODULE_LICENSE("GPL");
4707MODULE_ALIAS_NETPROTO(PF_PACKET);