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v4.6
 
  1#include <linux/types.h>
  2#include <linux/spinlock.h>
  3#include <linux/sock_diag.h>
  4#include <linux/unix_diag.h>
  5#include <linux/skbuff.h>
  6#include <linux/module.h>
 
  7#include <net/netlink.h>
  8#include <net/af_unix.h>
  9#include <net/tcp_states.h>
 
 10
 11static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb)
 12{
 13	struct unix_address *addr = unix_sk(sk)->addr;
 
 14
 15	if (!addr)
 16		return 0;
 17
 18	return nla_put(nlskb, UNIX_DIAG_NAME, addr->len - sizeof(short),
 
 19		       addr->name->sun_path);
 20}
 21
 22static int sk_diag_dump_vfs(struct sock *sk, struct sk_buff *nlskb)
 23{
 24	struct dentry *dentry = unix_sk(sk)->path.dentry;
 25
 26	if (dentry) {
 27		struct unix_diag_vfs uv = {
 28			.udiag_vfs_ino = d_backing_inode(dentry)->i_ino,
 29			.udiag_vfs_dev = dentry->d_sb->s_dev,
 30		};
 31
 32		return nla_put(nlskb, UNIX_DIAG_VFS, sizeof(uv), &uv);
 33	}
 34
 35	return 0;
 36}
 37
 38static int sk_diag_dump_peer(struct sock *sk, struct sk_buff *nlskb)
 39{
 40	struct sock *peer;
 41	int ino;
 42
 43	peer = unix_peer_get(sk);
 44	if (peer) {
 45		unix_state_lock(peer);
 46		ino = sock_i_ino(peer);
 47		unix_state_unlock(peer);
 48		sock_put(peer);
 49
 50		return nla_put_u32(nlskb, UNIX_DIAG_PEER, ino);
 51	}
 52
 53	return 0;
 54}
 55
 56static int sk_diag_dump_icons(struct sock *sk, struct sk_buff *nlskb)
 57{
 58	struct sk_buff *skb;
 59	struct nlattr *attr;
 60	u32 *buf;
 61	int i;
 62
 63	if (sk->sk_state == TCP_LISTEN) {
 64		spin_lock(&sk->sk_receive_queue.lock);
 65
 66		attr = nla_reserve(nlskb, UNIX_DIAG_ICONS,
 67				   sk->sk_receive_queue.qlen * sizeof(u32));
 68		if (!attr)
 69			goto errout;
 70
 71		buf = nla_data(attr);
 72		i = 0;
 73		skb_queue_walk(&sk->sk_receive_queue, skb) {
 74			struct sock *req, *peer;
 75
 76			req = skb->sk;
 77			/*
 78			 * The state lock is outer for the same sk's
 79			 * queue lock. With the other's queue locked it's
 80			 * OK to lock the state.
 81			 */
 82			unix_state_lock_nested(req);
 83			peer = unix_sk(req)->peer;
 84			buf[i++] = (peer ? sock_i_ino(peer) : 0);
 85			unix_state_unlock(req);
 86		}
 87		spin_unlock(&sk->sk_receive_queue.lock);
 88	}
 89
 90	return 0;
 91
 92errout:
 93	spin_unlock(&sk->sk_receive_queue.lock);
 94	return -EMSGSIZE;
 95}
 96
 97static int sk_diag_show_rqlen(struct sock *sk, struct sk_buff *nlskb)
 98{
 99	struct unix_diag_rqlen rql;
100
101	if (sk->sk_state == TCP_LISTEN) {
102		rql.udiag_rqueue = sk->sk_receive_queue.qlen;
103		rql.udiag_wqueue = sk->sk_max_ack_backlog;
104	} else {
105		rql.udiag_rqueue = (u32) unix_inq_len(sk);
106		rql.udiag_wqueue = (u32) unix_outq_len(sk);
107	}
108
109	return nla_put(nlskb, UNIX_DIAG_RQLEN, sizeof(rql), &rql);
110}
111
 
 
 
 
 
 
 
112static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
113		u32 portid, u32 seq, u32 flags, int sk_ino)
 
114{
115	struct nlmsghdr *nlh;
116	struct unix_diag_msg *rep;
117
118	nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
119			flags);
120	if (!nlh)
121		return -EMSGSIZE;
122
123	rep = nlmsg_data(nlh);
124	rep->udiag_family = AF_UNIX;
125	rep->udiag_type = sk->sk_type;
126	rep->udiag_state = sk->sk_state;
127	rep->pad = 0;
128	rep->udiag_ino = sk_ino;
129	sock_diag_save_cookie(sk, rep->udiag_cookie);
130
131	if ((req->udiag_show & UDIAG_SHOW_NAME) &&
132	    sk_diag_dump_name(sk, skb))
133		goto out_nlmsg_trim;
134
135	if ((req->udiag_show & UDIAG_SHOW_VFS) &&
136	    sk_diag_dump_vfs(sk, skb))
137		goto out_nlmsg_trim;
138
139	if ((req->udiag_show & UDIAG_SHOW_PEER) &&
140	    sk_diag_dump_peer(sk, skb))
141		goto out_nlmsg_trim;
142
143	if ((req->udiag_show & UDIAG_SHOW_ICONS) &&
144	    sk_diag_dump_icons(sk, skb))
145		goto out_nlmsg_trim;
146
147	if ((req->udiag_show & UDIAG_SHOW_RQLEN) &&
148	    sk_diag_show_rqlen(sk, skb))
149		goto out_nlmsg_trim;
150
151	if ((req->udiag_show & UDIAG_SHOW_MEMINFO) &&
152	    sock_diag_put_meminfo(sk, skb, UNIX_DIAG_MEMINFO))
153		goto out_nlmsg_trim;
154
155	if (nla_put_u8(skb, UNIX_DIAG_SHUTDOWN, sk->sk_shutdown))
156		goto out_nlmsg_trim;
157
 
 
 
 
158	nlmsg_end(skb, nlh);
159	return 0;
160
161out_nlmsg_trim:
162	nlmsg_cancel(skb, nlh);
163	return -EMSGSIZE;
164}
165
166static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
167		u32 portid, u32 seq, u32 flags)
 
168{
169	int sk_ino;
170
171	unix_state_lock(sk);
172	sk_ino = sock_i_ino(sk);
173	unix_state_unlock(sk);
174
175	if (!sk_ino)
176		return 0;
177
178	return sk_diag_fill(sk, skb, req, portid, seq, flags, sk_ino);
179}
180
181static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
182{
183	struct unix_diag_req *req;
184	int num, s_num, slot, s_slot;
185	struct net *net = sock_net(skb->sk);
 
 
186
187	req = nlmsg_data(cb->nlh);
188
189	s_slot = cb->args[0];
190	num = s_num = cb->args[1];
191
192	spin_lock(&unix_table_lock);
193	for (slot = s_slot;
194	     slot < ARRAY_SIZE(unix_socket_table);
195	     s_num = 0, slot++) {
196		struct sock *sk;
197
198		num = 0;
199		sk_for_each(sk, &unix_socket_table[slot]) {
200			if (!net_eq(sock_net(sk), net))
201				continue;
202			if (num < s_num)
203				goto next;
204			if (!(req->udiag_states & (1 << sk->sk_state)))
205				goto next;
206			if (sk_diag_dump(sk, skb, req,
207					 NETLINK_CB(cb->skb).portid,
208					 cb->nlh->nlmsg_seq,
209					 NLM_F_MULTI) < 0)
 
210				goto done;
 
211next:
212			num++;
213		}
 
214	}
215done:
216	spin_unlock(&unix_table_lock);
217	cb->args[0] = slot;
218	cb->args[1] = num;
219
220	return skb->len;
221}
222
223static struct sock *unix_lookup_by_ino(unsigned int ino)
224{
225	int i;
226	struct sock *sk;
 
227
228	spin_lock(&unix_table_lock);
229	for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) {
230		sk_for_each(sk, &unix_socket_table[i])
231			if (ino == sock_i_ino(sk)) {
232				sock_hold(sk);
233				spin_unlock(&unix_table_lock);
234
235				return sk;
236			}
 
 
237	}
238
239	spin_unlock(&unix_table_lock);
240	return NULL;
241}
242
243static int unix_diag_get_exact(struct sk_buff *in_skb,
244			       const struct nlmsghdr *nlh,
245			       struct unix_diag_req *req)
246{
247	int err = -EINVAL;
248	struct sock *sk;
249	struct sk_buff *rep;
250	unsigned int extra_len;
251	struct net *net = sock_net(in_skb->sk);
 
 
 
 
252
 
253	if (req->udiag_ino == 0)
254		goto out_nosk;
255
256	sk = unix_lookup_by_ino(req->udiag_ino);
257	err = -ENOENT;
258	if (sk == NULL)
259		goto out_nosk;
260
261	err = sock_diag_check_cookie(sk, req->udiag_cookie);
262	if (err)
263		goto out;
264
265	extra_len = 256;
266again:
267	err = -ENOMEM;
268	rep = nlmsg_new(sizeof(struct unix_diag_msg) + extra_len, GFP_KERNEL);
269	if (!rep)
270		goto out;
271
272	err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).portid,
 
273			   nlh->nlmsg_seq, 0, req->udiag_ino);
274	if (err < 0) {
275		nlmsg_free(rep);
276		extra_len += 256;
277		if (extra_len >= PAGE_SIZE)
278			goto out;
279
280		goto again;
281	}
282	err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
283			      MSG_DONTWAIT);
284	if (err > 0)
285		err = 0;
286out:
287	if (sk)
288		sock_put(sk);
289out_nosk:
290	return err;
291}
292
293static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
294{
295	int hdrlen = sizeof(struct unix_diag_req);
296	struct net *net = sock_net(skb->sk);
297
298	if (nlmsg_len(h) < hdrlen)
299		return -EINVAL;
300
301	if (h->nlmsg_flags & NLM_F_DUMP) {
302		struct netlink_dump_control c = {
303			.dump = unix_diag_dump,
304		};
305		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
306	} else
307		return unix_diag_get_exact(skb, h, nlmsg_data(h));
308}
309
310static const struct sock_diag_handler unix_diag_handler = {
 
311	.family = AF_UNIX,
312	.dump = unix_diag_handler_dump,
313};
314
315static int __init unix_diag_init(void)
316{
317	return sock_diag_register(&unix_diag_handler);
318}
319
320static void __exit unix_diag_exit(void)
321{
322	sock_diag_unregister(&unix_diag_handler);
323}
324
325module_init(unix_diag_init);
326module_exit(unix_diag_exit);
327MODULE_LICENSE("GPL");
 
328MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 1 /* AF_LOCAL */);
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2#include <linux/types.h>
  3#include <linux/spinlock.h>
  4#include <linux/sock_diag.h>
  5#include <linux/unix_diag.h>
  6#include <linux/skbuff.h>
  7#include <linux/module.h>
  8#include <linux/uidgid.h>
  9#include <net/netlink.h>
 10#include <net/af_unix.h>
 11#include <net/tcp_states.h>
 12#include <net/sock.h>
 13
 14static int sk_diag_dump_name(struct sock *sk, struct sk_buff *nlskb)
 15{
 16	/* might or might not have a hash table lock */
 17	struct unix_address *addr = smp_load_acquire(&unix_sk(sk)->addr);
 18
 19	if (!addr)
 20		return 0;
 21
 22	return nla_put(nlskb, UNIX_DIAG_NAME,
 23		       addr->len - offsetof(struct sockaddr_un, sun_path),
 24		       addr->name->sun_path);
 25}
 26
 27static int sk_diag_dump_vfs(struct sock *sk, struct sk_buff *nlskb)
 28{
 29	struct dentry *dentry = unix_sk(sk)->path.dentry;
 30
 31	if (dentry) {
 32		struct unix_diag_vfs uv = {
 33			.udiag_vfs_ino = d_backing_inode(dentry)->i_ino,
 34			.udiag_vfs_dev = dentry->d_sb->s_dev,
 35		};
 36
 37		return nla_put(nlskb, UNIX_DIAG_VFS, sizeof(uv), &uv);
 38	}
 39
 40	return 0;
 41}
 42
 43static int sk_diag_dump_peer(struct sock *sk, struct sk_buff *nlskb)
 44{
 45	struct sock *peer;
 46	int ino;
 47
 48	peer = unix_peer_get(sk);
 49	if (peer) {
 50		unix_state_lock(peer);
 51		ino = sock_i_ino(peer);
 52		unix_state_unlock(peer);
 53		sock_put(peer);
 54
 55		return nla_put_u32(nlskb, UNIX_DIAG_PEER, ino);
 56	}
 57
 58	return 0;
 59}
 60
 61static int sk_diag_dump_icons(struct sock *sk, struct sk_buff *nlskb)
 62{
 63	struct sk_buff *skb;
 64	struct nlattr *attr;
 65	u32 *buf;
 66	int i;
 67
 68	if (sk->sk_state == TCP_LISTEN) {
 69		spin_lock(&sk->sk_receive_queue.lock);
 70
 71		attr = nla_reserve(nlskb, UNIX_DIAG_ICONS,
 72				   sk->sk_receive_queue.qlen * sizeof(u32));
 73		if (!attr)
 74			goto errout;
 75
 76		buf = nla_data(attr);
 77		i = 0;
 78		skb_queue_walk(&sk->sk_receive_queue, skb) {
 79			struct sock *req, *peer;
 80
 81			req = skb->sk;
 82			/*
 83			 * The state lock is outer for the same sk's
 84			 * queue lock. With the other's queue locked it's
 85			 * OK to lock the state.
 86			 */
 87			unix_state_lock_nested(req, U_LOCK_DIAG);
 88			peer = unix_sk(req)->peer;
 89			buf[i++] = (peer ? sock_i_ino(peer) : 0);
 90			unix_state_unlock(req);
 91		}
 92		spin_unlock(&sk->sk_receive_queue.lock);
 93	}
 94
 95	return 0;
 96
 97errout:
 98	spin_unlock(&sk->sk_receive_queue.lock);
 99	return -EMSGSIZE;
100}
101
102static int sk_diag_show_rqlen(struct sock *sk, struct sk_buff *nlskb)
103{
104	struct unix_diag_rqlen rql;
105
106	if (sk->sk_state == TCP_LISTEN) {
107		rql.udiag_rqueue = sk->sk_receive_queue.qlen;
108		rql.udiag_wqueue = sk->sk_max_ack_backlog;
109	} else {
110		rql.udiag_rqueue = (u32) unix_inq_len(sk);
111		rql.udiag_wqueue = (u32) unix_outq_len(sk);
112	}
113
114	return nla_put(nlskb, UNIX_DIAG_RQLEN, sizeof(rql), &rql);
115}
116
117static int sk_diag_dump_uid(struct sock *sk, struct sk_buff *nlskb,
118			    struct user_namespace *user_ns)
119{
120	uid_t uid = from_kuid_munged(user_ns, sock_i_uid(sk));
121	return nla_put(nlskb, UNIX_DIAG_UID, sizeof(uid_t), &uid);
122}
123
124static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
125			struct user_namespace *user_ns,
126			u32 portid, u32 seq, u32 flags, int sk_ino)
127{
128	struct nlmsghdr *nlh;
129	struct unix_diag_msg *rep;
130
131	nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
132			flags);
133	if (!nlh)
134		return -EMSGSIZE;
135
136	rep = nlmsg_data(nlh);
137	rep->udiag_family = AF_UNIX;
138	rep->udiag_type = sk->sk_type;
139	rep->udiag_state = sk->sk_state;
140	rep->pad = 0;
141	rep->udiag_ino = sk_ino;
142	sock_diag_save_cookie(sk, rep->udiag_cookie);
143
144	if ((req->udiag_show & UDIAG_SHOW_NAME) &&
145	    sk_diag_dump_name(sk, skb))
146		goto out_nlmsg_trim;
147
148	if ((req->udiag_show & UDIAG_SHOW_VFS) &&
149	    sk_diag_dump_vfs(sk, skb))
150		goto out_nlmsg_trim;
151
152	if ((req->udiag_show & UDIAG_SHOW_PEER) &&
153	    sk_diag_dump_peer(sk, skb))
154		goto out_nlmsg_trim;
155
156	if ((req->udiag_show & UDIAG_SHOW_ICONS) &&
157	    sk_diag_dump_icons(sk, skb))
158		goto out_nlmsg_trim;
159
160	if ((req->udiag_show & UDIAG_SHOW_RQLEN) &&
161	    sk_diag_show_rqlen(sk, skb))
162		goto out_nlmsg_trim;
163
164	if ((req->udiag_show & UDIAG_SHOW_MEMINFO) &&
165	    sock_diag_put_meminfo(sk, skb, UNIX_DIAG_MEMINFO))
166		goto out_nlmsg_trim;
167
168	if (nla_put_u8(skb, UNIX_DIAG_SHUTDOWN, sk->sk_shutdown))
169		goto out_nlmsg_trim;
170
171	if ((req->udiag_show & UDIAG_SHOW_UID) &&
172	    sk_diag_dump_uid(sk, skb, user_ns))
173		goto out_nlmsg_trim;
174
175	nlmsg_end(skb, nlh);
176	return 0;
177
178out_nlmsg_trim:
179	nlmsg_cancel(skb, nlh);
180	return -EMSGSIZE;
181}
182
183static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
184			struct user_namespace *user_ns,
185			u32 portid, u32 seq, u32 flags)
186{
187	int sk_ino;
188
189	unix_state_lock(sk);
190	sk_ino = sock_i_ino(sk);
191	unix_state_unlock(sk);
192
193	if (!sk_ino)
194		return 0;
195
196	return sk_diag_fill(sk, skb, req, user_ns, portid, seq, flags, sk_ino);
197}
198
199static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
200{
 
 
201	struct net *net = sock_net(skb->sk);
202	int num, s_num, slot, s_slot;
203	struct unix_diag_req *req;
204
205	req = nlmsg_data(cb->nlh);
206
207	s_slot = cb->args[0];
208	num = s_num = cb->args[1];
209
210	for (slot = s_slot; slot < UNIX_HASH_SIZE; s_num = 0, slot++) {
 
 
 
211		struct sock *sk;
212
213		num = 0;
214		spin_lock(&net->unx.table.locks[slot]);
215		sk_for_each(sk, &net->unx.table.buckets[slot]) {
 
216			if (num < s_num)
217				goto next;
218			if (!(req->udiag_states & (1 << sk->sk_state)))
219				goto next;
220			if (sk_diag_dump(sk, skb, req, sk_user_ns(skb->sk),
221					 NETLINK_CB(cb->skb).portid,
222					 cb->nlh->nlmsg_seq,
223					 NLM_F_MULTI) < 0) {
224				spin_unlock(&net->unx.table.locks[slot]);
225				goto done;
226			}
227next:
228			num++;
229		}
230		spin_unlock(&net->unx.table.locks[slot]);
231	}
232done:
 
233	cb->args[0] = slot;
234	cb->args[1] = num;
235
236	return skb->len;
237}
238
239static struct sock *unix_lookup_by_ino(struct net *net, unsigned int ino)
240{
 
241	struct sock *sk;
242	int i;
243
244	for (i = 0; i < UNIX_HASH_SIZE; i++) {
245		spin_lock(&net->unx.table.locks[i]);
246		sk_for_each(sk, &net->unx.table.buckets[i]) {
247			if (ino == sock_i_ino(sk)) {
248				sock_hold(sk);
249				spin_unlock(&net->unx.table.locks[i]);
 
250				return sk;
251			}
252		}
253		spin_unlock(&net->unx.table.locks[i]);
254	}
 
 
255	return NULL;
256}
257
258static int unix_diag_get_exact(struct sk_buff *in_skb,
259			       const struct nlmsghdr *nlh,
260			       struct unix_diag_req *req)
261{
 
 
 
 
262	struct net *net = sock_net(in_skb->sk);
263	unsigned int extra_len;
264	struct sk_buff *rep;
265	struct sock *sk;
266	int err;
267
268	err = -EINVAL;
269	if (req->udiag_ino == 0)
270		goto out_nosk;
271
272	sk = unix_lookup_by_ino(net, req->udiag_ino);
273	err = -ENOENT;
274	if (sk == NULL)
275		goto out_nosk;
276
277	err = sock_diag_check_cookie(sk, req->udiag_cookie);
278	if (err)
279		goto out;
280
281	extra_len = 256;
282again:
283	err = -ENOMEM;
284	rep = nlmsg_new(sizeof(struct unix_diag_msg) + extra_len, GFP_KERNEL);
285	if (!rep)
286		goto out;
287
288	err = sk_diag_fill(sk, rep, req, sk_user_ns(NETLINK_CB(in_skb).sk),
289			   NETLINK_CB(in_skb).portid,
290			   nlh->nlmsg_seq, 0, req->udiag_ino);
291	if (err < 0) {
292		nlmsg_free(rep);
293		extra_len += 256;
294		if (extra_len >= PAGE_SIZE)
295			goto out;
296
297		goto again;
298	}
299	err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
300
 
 
301out:
302	if (sk)
303		sock_put(sk);
304out_nosk:
305	return err;
306}
307
308static int unix_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
309{
310	int hdrlen = sizeof(struct unix_diag_req);
 
311
312	if (nlmsg_len(h) < hdrlen)
313		return -EINVAL;
314
315	if (h->nlmsg_flags & NLM_F_DUMP) {
316		struct netlink_dump_control c = {
317			.dump = unix_diag_dump,
318		};
319		return netlink_dump_start(sock_net(skb->sk)->diag_nlsk, skb, h, &c);
320	} else
321		return unix_diag_get_exact(skb, h, nlmsg_data(h));
322}
323
324static const struct sock_diag_handler unix_diag_handler = {
325	.owner = THIS_MODULE,
326	.family = AF_UNIX,
327	.dump = unix_diag_handler_dump,
328};
329
330static int __init unix_diag_init(void)
331{
332	return sock_diag_register(&unix_diag_handler);
333}
334
335static void __exit unix_diag_exit(void)
336{
337	sock_diag_unregister(&unix_diag_handler);
338}
339
340module_init(unix_diag_init);
341module_exit(unix_diag_exit);
342MODULE_LICENSE("GPL");
343MODULE_DESCRIPTION("UNIX socket monitoring via SOCK_DIAG");
344MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 1 /* AF_LOCAL */);