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v4.6
 
  1/*
  2 * Copyright (C) 2003-2008 Takahiro Hirofuchi
  3 *
  4 * This is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License as published by
  6 * the Free Software Foundation; either version 2 of the License, or
  7 * (at your option) any later version.
  8 *
  9 * This is distributed in the hope that it will be useful,
 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 12 * GNU General Public License for more details.
 13 *
 14 * You should have received a copy of the GNU General Public License
 15 * along with this program; if not, write to the Free Software
 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
 17 * USA.
 18 */
 19
 20#include <asm/byteorder.h>
 21#include <linux/kthread.h>
 22#include <linux/usb.h>
 23#include <linux/usb/hcd.h>
 
 24
 25#include "usbip_common.h"
 26#include "stub.h"
 27
 28static int is_clear_halt_cmd(struct urb *urb)
 29{
 30	struct usb_ctrlrequest *req;
 31
 32	req = (struct usb_ctrlrequest *) urb->setup_packet;
 33
 34	 return (req->bRequest == USB_REQ_CLEAR_FEATURE) &&
 35		 (req->bRequestType == USB_RECIP_ENDPOINT) &&
 36		 (req->wValue == USB_ENDPOINT_HALT);
 37}
 38
 39static int is_set_interface_cmd(struct urb *urb)
 40{
 41	struct usb_ctrlrequest *req;
 42
 43	req = (struct usb_ctrlrequest *) urb->setup_packet;
 44
 45	return (req->bRequest == USB_REQ_SET_INTERFACE) &&
 46		(req->bRequestType == USB_RECIP_INTERFACE);
 47}
 48
 49static int is_set_configuration_cmd(struct urb *urb)
 50{
 51	struct usb_ctrlrequest *req;
 52
 53	req = (struct usb_ctrlrequest *) urb->setup_packet;
 54
 55	return (req->bRequest == USB_REQ_SET_CONFIGURATION) &&
 56		(req->bRequestType == USB_RECIP_DEVICE);
 57}
 58
 59static int is_reset_device_cmd(struct urb *urb)
 60{
 61	struct usb_ctrlrequest *req;
 62	__u16 value;
 63	__u16 index;
 64
 65	req = (struct usb_ctrlrequest *) urb->setup_packet;
 66	value = le16_to_cpu(req->wValue);
 67	index = le16_to_cpu(req->wIndex);
 68
 69	if ((req->bRequest == USB_REQ_SET_FEATURE) &&
 70	    (req->bRequestType == USB_RT_PORT) &&
 71	    (value == USB_PORT_FEAT_RESET)) {
 72		usbip_dbg_stub_rx("reset_device_cmd, port %u\n", index);
 73		return 1;
 74	} else
 75		return 0;
 76}
 77
 78static int tweak_clear_halt_cmd(struct urb *urb)
 79{
 80	struct usb_ctrlrequest *req;
 81	int target_endp;
 82	int target_dir;
 83	int target_pipe;
 84	int ret;
 85
 86	req = (struct usb_ctrlrequest *) urb->setup_packet;
 87
 88	/*
 89	 * The stalled endpoint is specified in the wIndex value. The endpoint
 90	 * of the urb is the target of this clear_halt request (i.e., control
 91	 * endpoint).
 92	 */
 93	target_endp = le16_to_cpu(req->wIndex) & 0x000f;
 94
 95	/* the stalled endpoint direction is IN or OUT?. USB_DIR_IN is 0x80.  */
 96	target_dir = le16_to_cpu(req->wIndex) & 0x0080;
 97
 98	if (target_dir)
 99		target_pipe = usb_rcvctrlpipe(urb->dev, target_endp);
100	else
101		target_pipe = usb_sndctrlpipe(urb->dev, target_endp);
102
103	ret = usb_clear_halt(urb->dev, target_pipe);
104	if (ret < 0)
105		dev_err(&urb->dev->dev,
106			"usb_clear_halt error: devnum %d endp %d ret %d\n",
107			urb->dev->devnum, target_endp, ret);
108	else
109		dev_info(&urb->dev->dev,
110			 "usb_clear_halt done: devnum %d endp %d\n",
111			 urb->dev->devnum, target_endp);
112
113	return ret;
114}
115
116static int tweak_set_interface_cmd(struct urb *urb)
117{
118	struct usb_ctrlrequest *req;
119	__u16 alternate;
120	__u16 interface;
121	int ret;
122
123	req = (struct usb_ctrlrequest *) urb->setup_packet;
124	alternate = le16_to_cpu(req->wValue);
125	interface = le16_to_cpu(req->wIndex);
126
127	usbip_dbg_stub_rx("set_interface: inf %u alt %u\n",
128			  interface, alternate);
129
130	ret = usb_set_interface(urb->dev, interface, alternate);
131	if (ret < 0)
132		dev_err(&urb->dev->dev,
133			"usb_set_interface error: inf %u alt %u ret %d\n",
134			interface, alternate, ret);
135	else
136		dev_info(&urb->dev->dev,
137			"usb_set_interface done: inf %u alt %u\n",
138			interface, alternate);
139
140	return ret;
141}
142
143static int tweak_set_configuration_cmd(struct urb *urb)
144{
145	struct stub_priv *priv = (struct stub_priv *) urb->context;
146	struct stub_device *sdev = priv->sdev;
147	struct usb_ctrlrequest *req;
148	__u16 config;
149	int err;
150
151	req = (struct usb_ctrlrequest *) urb->setup_packet;
152	config = le16_to_cpu(req->wValue);
153
 
154	err = usb_set_configuration(sdev->udev, config);
 
155	if (err && err != -ENODEV)
156		dev_err(&sdev->udev->dev, "can't set config #%d, error %d\n",
157			config, err);
158	return 0;
159}
160
161static int tweak_reset_device_cmd(struct urb *urb)
162{
163	struct stub_priv *priv = (struct stub_priv *) urb->context;
164	struct stub_device *sdev = priv->sdev;
 
165
166	dev_info(&urb->dev->dev, "usb_queue_reset_device\n");
167
168	/*
169	 * With the implementation of pre_reset and post_reset the driver no
170	 * longer unbinds. This allows the use of synchronous reset.
171	 */
172
173	if (usb_lock_device_for_reset(sdev->udev, sdev->interface) < 0) {
174		dev_err(&urb->dev->dev, "could not obtain lock to reset device\n");
175		return 0;
176	}
177	usb_reset_device(sdev->udev);
178	usb_unlock_device(sdev->udev);
179
180	return 0;
181}
182
183/*
184 * clear_halt, set_interface, and set_configuration require special tricks.
 
185 */
186static void tweak_special_requests(struct urb *urb)
187{
 
 
188	if (!urb || !urb->setup_packet)
189		return;
190
191	if (usb_pipetype(urb->pipe) != PIPE_CONTROL)
192		return;
193
194	if (is_clear_halt_cmd(urb))
195		/* tweak clear_halt */
196		 tweak_clear_halt_cmd(urb);
197
198	else if (is_set_interface_cmd(urb))
199		/* tweak set_interface */
200		tweak_set_interface_cmd(urb);
201
202	else if (is_set_configuration_cmd(urb))
203		/* tweak set_configuration */
204		tweak_set_configuration_cmd(urb);
205
206	else if (is_reset_device_cmd(urb))
207		tweak_reset_device_cmd(urb);
208	else
209		usbip_dbg_stub_rx("no need to tweak\n");
 
 
 
 
210}
211
212/*
213 * stub_recv_unlink() unlinks the URB by a call to usb_unlink_urb().
214 * By unlinking the urb asynchronously, stub_rx can continuously
215 * process coming urbs.  Even if the urb is unlinked, its completion
216 * handler will be called and stub_tx will send a return pdu.
217 *
218 * See also comments about unlinking strategy in vhci_hcd.c.
219 */
220static int stub_recv_cmd_unlink(struct stub_device *sdev,
221				struct usbip_header *pdu)
222{
223	int ret;
224	unsigned long flags;
225	struct stub_priv *priv;
226
227	spin_lock_irqsave(&sdev->priv_lock, flags);
228
229	list_for_each_entry(priv, &sdev->priv_init, list) {
230		if (priv->seqnum != pdu->u.cmd_unlink.seqnum)
231			continue;
232
233		dev_info(&priv->urb->dev->dev, "unlink urb %p\n",
234			 priv->urb);
235
236		/*
237		 * This matched urb is not completed yet (i.e., be in
238		 * flight in usb hcd hardware/driver). Now we are
239		 * cancelling it. The unlinking flag means that we are
240		 * now not going to return the normal result pdu of a
241		 * submission request, but going to return a result pdu
242		 * of the unlink request.
243		 */
244		priv->unlinking = 1;
245
246		/*
247		 * In the case that unlinking flag is on, prev->seqnum
248		 * is changed from the seqnum of the cancelling urb to
249		 * the seqnum of the unlink request. This will be used
250		 * to make the result pdu of the unlink request.
251		 */
252		priv->seqnum = pdu->base.seqnum;
253
254		spin_unlock_irqrestore(&sdev->priv_lock, flags);
255
256		/*
257		 * usb_unlink_urb() is now out of spinlocking to avoid
258		 * spinlock recursion since stub_complete() is
259		 * sometimes called in this context but not in the
260		 * interrupt context.  If stub_complete() is executed
261		 * before we call usb_unlink_urb(), usb_unlink_urb()
262		 * will return an error value. In this case, stub_tx
263		 * will return the result pdu of this unlink request
264		 * though submission is completed and actual unlinking
265		 * is not executed. OK?
266		 */
267		/* In the above case, urb->status is not -ECONNRESET,
268		 * so a driver in a client host will know the failure
269		 * of the unlink request ?
270		 */
271		ret = usb_unlink_urb(priv->urb);
272		if (ret != -EINPROGRESS)
273			dev_err(&priv->urb->dev->dev,
274				"failed to unlink a urb %p, ret %d\n",
275				priv->urb, ret);
276
 
 
277		return 0;
278	}
279
280	usbip_dbg_stub_rx("seqnum %d is not pending\n",
281			  pdu->u.cmd_unlink.seqnum);
282
283	/*
284	 * The urb of the unlink target is not found in priv_init queue. It was
285	 * already completed and its results is/was going to be sent by a
286	 * CMD_RET pdu. In this case, usb_unlink_urb() is not needed. We only
287	 * return the completeness of this unlink request to vhci_hcd.
288	 */
289	stub_enqueue_ret_unlink(sdev, pdu->base.seqnum, 0);
290
291	spin_unlock_irqrestore(&sdev->priv_lock, flags);
292
293	return 0;
294}
295
296static int valid_request(struct stub_device *sdev, struct usbip_header *pdu)
297{
298	struct usbip_device *ud = &sdev->ud;
299	int valid = 0;
300
301	if (pdu->base.devid == sdev->devid) {
302		spin_lock_irq(&ud->lock);
303		if (ud->status == SDEV_ST_USED) {
304			/* A request is valid. */
305			valid = 1;
306		}
307		spin_unlock_irq(&ud->lock);
308	}
309
310	return valid;
311}
312
313static struct stub_priv *stub_priv_alloc(struct stub_device *sdev,
314					 struct usbip_header *pdu)
315{
316	struct stub_priv *priv;
317	struct usbip_device *ud = &sdev->ud;
318	unsigned long flags;
319
320	spin_lock_irqsave(&sdev->priv_lock, flags);
321
322	priv = kmem_cache_zalloc(stub_priv_cache, GFP_ATOMIC);
323	if (!priv) {
324		dev_err(&sdev->interface->dev, "alloc stub_priv\n");
325		spin_unlock_irqrestore(&sdev->priv_lock, flags);
326		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
327		return NULL;
328	}
329
330	priv->seqnum = pdu->base.seqnum;
331	priv->sdev = sdev;
332
333	/*
334	 * After a stub_priv is linked to a list_head,
335	 * our error handler can free allocated data.
336	 */
337	list_add_tail(&priv->list, &sdev->priv_init);
338
339	spin_unlock_irqrestore(&sdev->priv_lock, flags);
340
341	return priv;
342}
343
344static int get_pipe(struct stub_device *sdev, int epnum, int dir)
345{
346	struct usb_device *udev = sdev->udev;
347	struct usb_host_endpoint *ep;
348	struct usb_endpoint_descriptor *epd = NULL;
 
 
 
 
 
349
350	if (dir == USBIP_DIR_IN)
351		ep = udev->ep_in[epnum & 0x7f];
352	else
353		ep = udev->ep_out[epnum & 0x7f];
354	if (!ep) {
355		dev_err(&sdev->interface->dev, "no such endpoint?, %d\n",
356			epnum);
357		BUG();
358	}
359
360	epd = &ep->desc;
 
361	if (usb_endpoint_xfer_control(epd)) {
362		if (dir == USBIP_DIR_OUT)
363			return usb_sndctrlpipe(udev, epnum);
364		else
365			return usb_rcvctrlpipe(udev, epnum);
366	}
367
368	if (usb_endpoint_xfer_bulk(epd)) {
369		if (dir == USBIP_DIR_OUT)
370			return usb_sndbulkpipe(udev, epnum);
371		else
372			return usb_rcvbulkpipe(udev, epnum);
373	}
374
375	if (usb_endpoint_xfer_int(epd)) {
376		if (dir == USBIP_DIR_OUT)
377			return usb_sndintpipe(udev, epnum);
378		else
379			return usb_rcvintpipe(udev, epnum);
380	}
381
382	if (usb_endpoint_xfer_isoc(epd)) {
 
 
 
 
 
 
 
 
 
383		if (dir == USBIP_DIR_OUT)
384			return usb_sndisocpipe(udev, epnum);
385		else
386			return usb_rcvisocpipe(udev, epnum);
387	}
388
 
389	/* NOT REACHED */
390	dev_err(&sdev->interface->dev, "get pipe, epnum %d\n", epnum);
391	return 0;
392}
393
394static void masking_bogus_flags(struct urb *urb)
395{
396	int				xfertype;
397	struct usb_device		*dev;
398	struct usb_host_endpoint	*ep;
399	int				is_out;
400	unsigned int	allowed;
401
402	if (!urb || urb->hcpriv || !urb->complete)
403		return;
404	dev = urb->dev;
405	if ((!dev) || (dev->state < USB_STATE_UNAUTHENTICATED))
406		return;
407
408	ep = (usb_pipein(urb->pipe) ? dev->ep_in : dev->ep_out)
409		[usb_pipeendpoint(urb->pipe)];
410	if (!ep)
411		return;
412
413	xfertype = usb_endpoint_type(&ep->desc);
414	if (xfertype == USB_ENDPOINT_XFER_CONTROL) {
415		struct usb_ctrlrequest *setup =
416			(struct usb_ctrlrequest *) urb->setup_packet;
417
418		if (!setup)
419			return;
420		is_out = !(setup->bRequestType & USB_DIR_IN) ||
421			!setup->wLength;
422	} else {
423		is_out = usb_endpoint_dir_out(&ep->desc);
424	}
425
426	/* enforce simple/standard policy */
427	allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT |
428		   URB_DIR_MASK | URB_FREE_BUFFER);
429	switch (xfertype) {
430	case USB_ENDPOINT_XFER_BULK:
431		if (is_out)
432			allowed |= URB_ZERO_PACKET;
433		/* FALLTHROUGH */
434	case USB_ENDPOINT_XFER_CONTROL:
435		allowed |= URB_NO_FSBR;	/* only affects UHCI */
436		/* FALLTHROUGH */
437	default:			/* all non-iso endpoints */
438		if (!is_out)
439			allowed |= URB_SHORT_NOT_OK;
440		break;
441	case USB_ENDPOINT_XFER_ISOC:
442		allowed |= URB_ISO_ASAP;
443		break;
444	}
445	urb->transfer_flags &= allowed;
446}
447
 
 
 
 
 
 
 
 
 
 
 
 
 
 
448static void stub_recv_cmd_submit(struct stub_device *sdev,
449				 struct usbip_header *pdu)
450{
451	int ret;
452	struct stub_priv *priv;
453	struct usbip_device *ud = &sdev->ud;
454	struct usb_device *udev = sdev->udev;
455	int pipe = get_pipe(sdev, pdu->base.ep, pdu->base.direction);
 
 
 
 
 
 
 
 
 
 
456
 
 
 
 
 
 
 
 
457	priv = stub_priv_alloc(sdev, pdu);
458	if (!priv)
459		return;
460
461	/* setup a urb */
462	if (usb_pipeisoc(pipe))
463		priv->urb = usb_alloc_urb(pdu->u.cmd_submit.number_of_packets,
464					  GFP_KERNEL);
465	else
466		priv->urb = usb_alloc_urb(0, GFP_KERNEL);
467
468	if (!priv->urb) {
469		dev_err(&sdev->interface->dev, "malloc urb\n");
470		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
471		return;
472	}
473
474	/* allocate urb transfer buffer, if needed */
475	if (pdu->u.cmd_submit.transfer_buffer_length > 0) {
476		priv->urb->transfer_buffer =
477			kzalloc(pdu->u.cmd_submit.transfer_buffer_length,
478				GFP_KERNEL);
479		if (!priv->urb->transfer_buffer) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
480			usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
481			return;
482		}
483	}
484
485	/* copy urb setup packet */
486	priv->urb->setup_packet = kmemdup(&pdu->u.cmd_submit.setup, 8,
487					  GFP_KERNEL);
488	if (!priv->urb->setup_packet) {
489		dev_err(&sdev->interface->dev, "allocate setup_packet\n");
490		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
491		return;
 
 
 
 
 
 
 
 
492	}
493
494	/* set other members from the base header of pdu */
495	priv->urb->context                = (void *) priv;
496	priv->urb->dev                    = udev;
497	priv->urb->pipe                   = pipe;
498	priv->urb->complete               = stub_complete;
 
499
500	usbip_pack_pdu(pdu, priv->urb, USBIP_CMD_SUBMIT, 0);
 
 
 
 
501
 
 
502
503	if (usbip_recv_xbuff(ud, priv->urb) < 0)
504		return;
505
506	if (usbip_recv_iso(ud, priv->urb) < 0)
507		return;
508
509	/* no need to submit an intercepted request, but harmless? */
510	tweak_special_requests(priv->urb);
511
512	masking_bogus_flags(priv->urb);
513	/* urb is now ready to submit */
514	ret = usb_submit_urb(priv->urb, GFP_KERNEL);
515
516	if (ret == 0)
517		usbip_dbg_stub_rx("submit urb ok, seqnum %u\n",
518				  pdu->base.seqnum);
519	else {
520		dev_err(&sdev->interface->dev, "submit_urb error, %d\n", ret);
521		usbip_dump_header(pdu);
522		usbip_dump_urb(priv->urb);
523
524		/*
525		 * Pessimistic.
526		 * This connection will be discarded.
527		 */
528		usbip_event_add(ud, SDEV_EVENT_ERROR_SUBMIT);
 
 
 
 
 
 
 
 
 
 
 
 
 
529	}
530
531	usbip_dbg_stub_rx("Leave\n");
 
 
 
 
 
 
 
 
 
532}
533
534/* recv a pdu */
535static void stub_rx_pdu(struct usbip_device *ud)
536{
537	int ret;
538	struct usbip_header pdu;
539	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
540	struct device *dev = &sdev->udev->dev;
541
542	usbip_dbg_stub_rx("Enter\n");
543
544	memset(&pdu, 0, sizeof(pdu));
545
546	/* receive a pdu header */
547	ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu));
548	if (ret != sizeof(pdu)) {
549		dev_err(dev, "recv a header, %d\n", ret);
550		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
551		return;
552	}
553
554	usbip_header_correct_endian(&pdu, 0);
555
556	if (usbip_dbg_flag_stub_rx)
557		usbip_dump_header(&pdu);
558
559	if (!valid_request(sdev, &pdu)) {
560		dev_err(dev, "recv invalid request\n");
561		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
562		return;
563	}
564
565	switch (pdu.base.command) {
566	case USBIP_CMD_UNLINK:
567		stub_recv_cmd_unlink(sdev, &pdu);
568		break;
569
570	case USBIP_CMD_SUBMIT:
571		stub_recv_cmd_submit(sdev, &pdu);
572		break;
573
574	default:
575		/* NOTREACHED */
576		dev_err(dev, "unknown pdu\n");
577		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
578		break;
579	}
580}
581
582int stub_rx_loop(void *data)
583{
584	struct usbip_device *ud = data;
585
586	while (!kthread_should_stop()) {
587		if (usbip_event_happened(ud))
588			break;
589
590		stub_rx_pdu(ud);
591	}
592
593	return 0;
594}
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  4 */
  5
  6#include <asm/byteorder.h>
  7#include <linux/kthread.h>
  8#include <linux/usb.h>
  9#include <linux/usb/hcd.h>
 10#include <linux/scatterlist.h>
 11
 12#include "usbip_common.h"
 13#include "stub.h"
 14
 15static int is_clear_halt_cmd(struct urb *urb)
 16{
 17	struct usb_ctrlrequest *req;
 18
 19	req = (struct usb_ctrlrequest *) urb->setup_packet;
 20
 21	return (req->bRequest == USB_REQ_CLEAR_FEATURE) &&
 22	       (req->bRequestType == USB_RECIP_ENDPOINT) &&
 23	       (req->wValue == USB_ENDPOINT_HALT);
 24}
 25
 26static int is_set_interface_cmd(struct urb *urb)
 27{
 28	struct usb_ctrlrequest *req;
 29
 30	req = (struct usb_ctrlrequest *) urb->setup_packet;
 31
 32	return (req->bRequest == USB_REQ_SET_INTERFACE) &&
 33		(req->bRequestType == USB_RECIP_INTERFACE);
 34}
 35
 36static int is_set_configuration_cmd(struct urb *urb)
 37{
 38	struct usb_ctrlrequest *req;
 39
 40	req = (struct usb_ctrlrequest *) urb->setup_packet;
 41
 42	return (req->bRequest == USB_REQ_SET_CONFIGURATION) &&
 43		(req->bRequestType == USB_RECIP_DEVICE);
 44}
 45
 46static int is_reset_device_cmd(struct urb *urb)
 47{
 48	struct usb_ctrlrequest *req;
 49	__u16 value;
 50	__u16 index;
 51
 52	req = (struct usb_ctrlrequest *) urb->setup_packet;
 53	value = le16_to_cpu(req->wValue);
 54	index = le16_to_cpu(req->wIndex);
 55
 56	if ((req->bRequest == USB_REQ_SET_FEATURE) &&
 57	    (req->bRequestType == USB_RT_PORT) &&
 58	    (value == USB_PORT_FEAT_RESET)) {
 59		usbip_dbg_stub_rx("reset_device_cmd, port %u\n", index);
 60		return 1;
 61	} else
 62		return 0;
 63}
 64
 65static int tweak_clear_halt_cmd(struct urb *urb)
 66{
 67	struct usb_ctrlrequest *req;
 68	int target_endp;
 69	int target_dir;
 70	int target_pipe;
 71	int ret;
 72
 73	req = (struct usb_ctrlrequest *) urb->setup_packet;
 74
 75	/*
 76	 * The stalled endpoint is specified in the wIndex value. The endpoint
 77	 * of the urb is the target of this clear_halt request (i.e., control
 78	 * endpoint).
 79	 */
 80	target_endp = le16_to_cpu(req->wIndex) & 0x000f;
 81
 82	/* the stalled endpoint direction is IN or OUT?. USB_DIR_IN is 0x80.  */
 83	target_dir = le16_to_cpu(req->wIndex) & 0x0080;
 84
 85	if (target_dir)
 86		target_pipe = usb_rcvctrlpipe(urb->dev, target_endp);
 87	else
 88		target_pipe = usb_sndctrlpipe(urb->dev, target_endp);
 89
 90	ret = usb_clear_halt(urb->dev, target_pipe);
 91	if (ret < 0)
 92		dev_err(&urb->dev->dev,
 93			"usb_clear_halt error: devnum %d endp %d ret %d\n",
 94			urb->dev->devnum, target_endp, ret);
 95	else
 96		dev_info(&urb->dev->dev,
 97			 "usb_clear_halt done: devnum %d endp %d\n",
 98			 urb->dev->devnum, target_endp);
 99
100	return ret;
101}
102
103static int tweak_set_interface_cmd(struct urb *urb)
104{
105	struct usb_ctrlrequest *req;
106	__u16 alternate;
107	__u16 interface;
108	int ret;
109
110	req = (struct usb_ctrlrequest *) urb->setup_packet;
111	alternate = le16_to_cpu(req->wValue);
112	interface = le16_to_cpu(req->wIndex);
113
114	usbip_dbg_stub_rx("set_interface: inf %u alt %u\n",
115			  interface, alternate);
116
117	ret = usb_set_interface(urb->dev, interface, alternate);
118	if (ret < 0)
119		dev_err(&urb->dev->dev,
120			"usb_set_interface error: inf %u alt %u ret %d\n",
121			interface, alternate, ret);
122	else
123		dev_info(&urb->dev->dev,
124			"usb_set_interface done: inf %u alt %u\n",
125			interface, alternate);
126
127	return ret;
128}
129
130static int tweak_set_configuration_cmd(struct urb *urb)
131{
132	struct stub_priv *priv = (struct stub_priv *) urb->context;
133	struct stub_device *sdev = priv->sdev;
134	struct usb_ctrlrequest *req;
135	__u16 config;
136	int err;
137
138	req = (struct usb_ctrlrequest *) urb->setup_packet;
139	config = le16_to_cpu(req->wValue);
140
141	usb_lock_device(sdev->udev);
142	err = usb_set_configuration(sdev->udev, config);
143	usb_unlock_device(sdev->udev);
144	if (err && err != -ENODEV)
145		dev_err(&sdev->udev->dev, "can't set config #%d, error %d\n",
146			config, err);
147	return err;
148}
149
150static int tweak_reset_device_cmd(struct urb *urb)
151{
152	struct stub_priv *priv = (struct stub_priv *) urb->context;
153	struct stub_device *sdev = priv->sdev;
154	int err;
155
156	dev_info(&urb->dev->dev, "usb_queue_reset_device\n");
157
158	err = usb_lock_device_for_reset(sdev->udev, NULL);
159	if (err < 0) {
 
 
 
 
160		dev_err(&urb->dev->dev, "could not obtain lock to reset device\n");
161		return err;
162	}
163	err = usb_reset_device(sdev->udev);
164	usb_unlock_device(sdev->udev);
165
166	return err;
167}
168
169/*
170 * clear_halt, set_interface, and set_configuration require special tricks.
171 * Returns 1 if request was tweaked, 0 otherwise.
172 */
173static int tweak_special_requests(struct urb *urb)
174{
175	int err;
176
177	if (!urb || !urb->setup_packet)
178		return 0;
179
180	if (usb_pipetype(urb->pipe) != PIPE_CONTROL)
181		return 0;
182
183	if (is_clear_halt_cmd(urb))
184		/* tweak clear_halt */
185		err = tweak_clear_halt_cmd(urb);
186
187	else if (is_set_interface_cmd(urb))
188		/* tweak set_interface */
189		err = tweak_set_interface_cmd(urb);
190
191	else if (is_set_configuration_cmd(urb))
192		/* tweak set_configuration */
193		err = tweak_set_configuration_cmd(urb);
194
195	else if (is_reset_device_cmd(urb))
196		err = tweak_reset_device_cmd(urb);
197	else {
198		usbip_dbg_stub_rx("no need to tweak\n");
199		return 0;
200	}
201
202	return !err;
203}
204
205/*
206 * stub_recv_unlink() unlinks the URB by a call to usb_unlink_urb().
207 * By unlinking the urb asynchronously, stub_rx can continuously
208 * process coming urbs.  Even if the urb is unlinked, its completion
209 * handler will be called and stub_tx will send a return pdu.
210 *
211 * See also comments about unlinking strategy in vhci_hcd.c.
212 */
213static int stub_recv_cmd_unlink(struct stub_device *sdev,
214				struct usbip_header *pdu)
215{
216	int ret, i;
217	unsigned long flags;
218	struct stub_priv *priv;
219
220	spin_lock_irqsave(&sdev->priv_lock, flags);
221
222	list_for_each_entry(priv, &sdev->priv_init, list) {
223		if (priv->seqnum != pdu->u.cmd_unlink.seqnum)
224			continue;
225
 
 
 
226		/*
227		 * This matched urb is not completed yet (i.e., be in
228		 * flight in usb hcd hardware/driver). Now we are
229		 * cancelling it. The unlinking flag means that we are
230		 * now not going to return the normal result pdu of a
231		 * submission request, but going to return a result pdu
232		 * of the unlink request.
233		 */
234		priv->unlinking = 1;
235
236		/*
237		 * In the case that unlinking flag is on, prev->seqnum
238		 * is changed from the seqnum of the cancelling urb to
239		 * the seqnum of the unlink request. This will be used
240		 * to make the result pdu of the unlink request.
241		 */
242		priv->seqnum = pdu->base.seqnum;
243
244		spin_unlock_irqrestore(&sdev->priv_lock, flags);
245
246		/*
247		 * usb_unlink_urb() is now out of spinlocking to avoid
248		 * spinlock recursion since stub_complete() is
249		 * sometimes called in this context but not in the
250		 * interrupt context.  If stub_complete() is executed
251		 * before we call usb_unlink_urb(), usb_unlink_urb()
252		 * will return an error value. In this case, stub_tx
253		 * will return the result pdu of this unlink request
254		 * though submission is completed and actual unlinking
255		 * is not executed. OK?
256		 */
257		/* In the above case, urb->status is not -ECONNRESET,
258		 * so a driver in a client host will know the failure
259		 * of the unlink request ?
260		 */
261		for (i = priv->completed_urbs; i < priv->num_urbs; i++) {
262			ret = usb_unlink_urb(priv->urbs[i]);
263			if (ret != -EINPROGRESS)
264				dev_err(&priv->urbs[i]->dev->dev,
265					"failed to unlink %d/%d urb of seqnum %lu, ret %d\n",
266					i + 1, priv->num_urbs,
267					priv->seqnum, ret);
268		}
269		return 0;
270	}
271
272	usbip_dbg_stub_rx("seqnum %d is not pending\n",
273			  pdu->u.cmd_unlink.seqnum);
274
275	/*
276	 * The urb of the unlink target is not found in priv_init queue. It was
277	 * already completed and its results is/was going to be sent by a
278	 * CMD_RET pdu. In this case, usb_unlink_urb() is not needed. We only
279	 * return the completeness of this unlink request to vhci_hcd.
280	 */
281	stub_enqueue_ret_unlink(sdev, pdu->base.seqnum, 0);
282
283	spin_unlock_irqrestore(&sdev->priv_lock, flags);
284
285	return 0;
286}
287
288static int valid_request(struct stub_device *sdev, struct usbip_header *pdu)
289{
290	struct usbip_device *ud = &sdev->ud;
291	int valid = 0;
292
293	if (pdu->base.devid == sdev->devid) {
294		spin_lock_irq(&ud->lock);
295		if (ud->status == SDEV_ST_USED) {
296			/* A request is valid. */
297			valid = 1;
298		}
299		spin_unlock_irq(&ud->lock);
300	}
301
302	return valid;
303}
304
305static struct stub_priv *stub_priv_alloc(struct stub_device *sdev,
306					 struct usbip_header *pdu)
307{
308	struct stub_priv *priv;
309	struct usbip_device *ud = &sdev->ud;
310	unsigned long flags;
311
312	spin_lock_irqsave(&sdev->priv_lock, flags);
313
314	priv = kmem_cache_zalloc(stub_priv_cache, GFP_ATOMIC);
315	if (!priv) {
316		dev_err(&sdev->udev->dev, "alloc stub_priv\n");
317		spin_unlock_irqrestore(&sdev->priv_lock, flags);
318		usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
319		return NULL;
320	}
321
322	priv->seqnum = pdu->base.seqnum;
323	priv->sdev = sdev;
324
325	/*
326	 * After a stub_priv is linked to a list_head,
327	 * our error handler can free allocated data.
328	 */
329	list_add_tail(&priv->list, &sdev->priv_init);
330
331	spin_unlock_irqrestore(&sdev->priv_lock, flags);
332
333	return priv;
334}
335
336static int get_pipe(struct stub_device *sdev, struct usbip_header *pdu)
337{
338	struct usb_device *udev = sdev->udev;
339	struct usb_host_endpoint *ep;
340	struct usb_endpoint_descriptor *epd = NULL;
341	int epnum = pdu->base.ep;
342	int dir = pdu->base.direction;
343
344	if (epnum < 0 || epnum > 15)
345		goto err_ret;
346
347	if (dir == USBIP_DIR_IN)
348		ep = udev->ep_in[epnum & 0x7f];
349	else
350		ep = udev->ep_out[epnum & 0x7f];
351	if (!ep)
352		goto err_ret;
 
 
 
353
354	epd = &ep->desc;
355
356	if (usb_endpoint_xfer_control(epd)) {
357		if (dir == USBIP_DIR_OUT)
358			return usb_sndctrlpipe(udev, epnum);
359		else
360			return usb_rcvctrlpipe(udev, epnum);
361	}
362
363	if (usb_endpoint_xfer_bulk(epd)) {
364		if (dir == USBIP_DIR_OUT)
365			return usb_sndbulkpipe(udev, epnum);
366		else
367			return usb_rcvbulkpipe(udev, epnum);
368	}
369
370	if (usb_endpoint_xfer_int(epd)) {
371		if (dir == USBIP_DIR_OUT)
372			return usb_sndintpipe(udev, epnum);
373		else
374			return usb_rcvintpipe(udev, epnum);
375	}
376
377	if (usb_endpoint_xfer_isoc(epd)) {
378		/* validate number of packets */
379		if (pdu->u.cmd_submit.number_of_packets < 0 ||
380		    pdu->u.cmd_submit.number_of_packets >
381		    USBIP_MAX_ISO_PACKETS) {
382			dev_err(&sdev->udev->dev,
383				"CMD_SUBMIT: isoc invalid num packets %d\n",
384				pdu->u.cmd_submit.number_of_packets);
385			return -1;
386		}
387		if (dir == USBIP_DIR_OUT)
388			return usb_sndisocpipe(udev, epnum);
389		else
390			return usb_rcvisocpipe(udev, epnum);
391	}
392
393err_ret:
394	/* NOT REACHED */
395	dev_err(&sdev->udev->dev, "CMD_SUBMIT: invalid epnum %d\n", epnum);
396	return -1;
397}
398
399static void masking_bogus_flags(struct urb *urb)
400{
401	int				xfertype;
402	struct usb_device		*dev;
403	struct usb_host_endpoint	*ep;
404	int				is_out;
405	unsigned int	allowed;
406
407	if (!urb || urb->hcpriv || !urb->complete)
408		return;
409	dev = urb->dev;
410	if ((!dev) || (dev->state < USB_STATE_UNAUTHENTICATED))
411		return;
412
413	ep = (usb_pipein(urb->pipe) ? dev->ep_in : dev->ep_out)
414		[usb_pipeendpoint(urb->pipe)];
415	if (!ep)
416		return;
417
418	xfertype = usb_endpoint_type(&ep->desc);
419	if (xfertype == USB_ENDPOINT_XFER_CONTROL) {
420		struct usb_ctrlrequest *setup =
421			(struct usb_ctrlrequest *) urb->setup_packet;
422
423		if (!setup)
424			return;
425		is_out = !(setup->bRequestType & USB_DIR_IN) ||
426			!setup->wLength;
427	} else {
428		is_out = usb_endpoint_dir_out(&ep->desc);
429	}
430
431	/* enforce simple/standard policy */
432	allowed = (URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT |
433		   URB_DIR_MASK | URB_FREE_BUFFER);
434	switch (xfertype) {
435	case USB_ENDPOINT_XFER_BULK:
436		if (is_out)
437			allowed |= URB_ZERO_PACKET;
438		fallthrough;
 
 
 
439	default:			/* all non-iso endpoints */
440		if (!is_out)
441			allowed |= URB_SHORT_NOT_OK;
442		break;
443	case USB_ENDPOINT_XFER_ISOC:
444		allowed |= URB_ISO_ASAP;
445		break;
446	}
447	urb->transfer_flags &= allowed;
448}
449
450static int stub_recv_xbuff(struct usbip_device *ud, struct stub_priv *priv)
451{
452	int ret;
453	int i;
454
455	for (i = 0; i < priv->num_urbs; i++) {
456		ret = usbip_recv_xbuff(ud, priv->urbs[i]);
457		if (ret < 0)
458			break;
459	}
460
461	return ret;
462}
463
464static void stub_recv_cmd_submit(struct stub_device *sdev,
465				 struct usbip_header *pdu)
466{
 
467	struct stub_priv *priv;
468	struct usbip_device *ud = &sdev->ud;
469	struct usb_device *udev = sdev->udev;
470	struct scatterlist *sgl = NULL, *sg;
471	void *buffer = NULL;
472	unsigned long long buf_len;
473	int nents;
474	int num_urbs = 1;
475	int pipe = get_pipe(sdev, pdu);
476	int use_sg = pdu->u.cmd_submit.transfer_flags & USBIP_URB_DMA_MAP_SG;
477	int support_sg = 1;
478	int np = 0;
479	int ret, i;
480	int is_tweaked;
481
482	if (pipe == -1)
483		return;
484
485	/*
486	 * Smatch reported the error case where use_sg is true and buf_len is 0.
487	 * In this case, It adds SDEV_EVENT_ERROR_MALLOC and stub_priv will be
488	 * released by stub event handler and connection will be shut down.
489	 */
490	priv = stub_priv_alloc(sdev, pdu);
491	if (!priv)
492		return;
493
494	buf_len = (unsigned long long)pdu->u.cmd_submit.transfer_buffer_length;
 
 
 
 
 
495
496	if (use_sg && !buf_len) {
497		dev_err(&udev->dev, "sg buffer with zero length\n");
498		goto err_malloc;
 
499	}
500
501	/* allocate urb transfer buffer, if needed */
502	if (buf_len) {
503		if (use_sg) {
504			sgl = sgl_alloc(buf_len, GFP_KERNEL, &nents);
505			if (!sgl)
506				goto err_malloc;
507
508			/* Check if the server's HCD supports SG */
509			if (!udev->bus->sg_tablesize) {
510				/*
511				 * If the server's HCD doesn't support SG, break
512				 * a single SG request into several URBs and map
513				 * each SG list entry to corresponding URB
514				 * buffer. The previously allocated SG list is
515				 * stored in priv->sgl (If the server's HCD
516				 * support SG, SG list is stored only in
517				 * urb->sg) and it is used as an indicator that
518				 * the server split single SG request into
519				 * several URBs. Later, priv->sgl is used by
520				 * stub_complete() and stub_send_ret_submit() to
521				 * reassemble the divied URBs.
522				 */
523				support_sg = 0;
524				num_urbs = nents;
525				priv->completed_urbs = 0;
526				pdu->u.cmd_submit.transfer_flags &=
527								~USBIP_URB_DMA_MAP_SG;
528			}
529		} else {
530			buffer = kzalloc(buf_len, GFP_KERNEL);
531			if (!buffer)
532				goto err_malloc;
533		}
534	}
535
536	/* allocate urb array */
537	priv->num_urbs = num_urbs;
538	priv->urbs = kmalloc_array(num_urbs, sizeof(*priv->urbs), GFP_KERNEL);
539	if (!priv->urbs)
540		goto err_urbs;
541
542	/* setup a urb */
543	if (support_sg) {
544		if (usb_pipeisoc(pipe))
545			np = pdu->u.cmd_submit.number_of_packets;
546
547		priv->urbs[0] = usb_alloc_urb(np, GFP_KERNEL);
548		if (!priv->urbs[0])
549			goto err_urb;
550
551		if (buf_len) {
552			if (use_sg) {
553				priv->urbs[0]->sg = sgl;
554				priv->urbs[0]->num_sgs = nents;
555				priv->urbs[0]->transfer_buffer = NULL;
556			} else {
557				priv->urbs[0]->transfer_buffer = buffer;
558			}
559		}
560
561		/* copy urb setup packet */
562		priv->urbs[0]->setup_packet = kmemdup(&pdu->u.cmd_submit.setup,
563					8, GFP_KERNEL);
564		if (!priv->urbs[0]->setup_packet) {
565			usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
566			return;
567		}
 
568
569		usbip_pack_pdu(pdu, priv->urbs[0], USBIP_CMD_SUBMIT, 0);
570	} else {
571		for_each_sg(sgl, sg, nents, i) {
572			priv->urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
573			/* The URBs which is previously allocated will be freed
574			 * in stub_device_cleanup_urbs() if error occurs.
575			 */
576			if (!priv->urbs[i])
577				goto err_urb;
578
579			usbip_pack_pdu(pdu, priv->urbs[i], USBIP_CMD_SUBMIT, 0);
580			priv->urbs[i]->transfer_buffer = sg_virt(sg);
581			priv->urbs[i]->transfer_buffer_length = sg->length;
582		}
583		priv->sgl = sgl;
584	}
585
586	for (i = 0; i < num_urbs; i++) {
587		/* set other members from the base header of pdu */
588		priv->urbs[i]->context = (void *) priv;
589		priv->urbs[i]->dev = udev;
590		priv->urbs[i]->pipe = pipe;
591		priv->urbs[i]->complete = stub_complete;
592
593		/*
594		 * all URBs belong to a single PDU, so a global is_tweaked flag is
595		 * enough
596		 */
597		is_tweaked = tweak_special_requests(priv->urbs[i]);
598
599		masking_bogus_flags(priv->urbs[i]);
600	}
601
602	if (stub_recv_xbuff(ud, priv) < 0)
603		return;
604
605	if (usbip_recv_iso(ud, priv->urbs[0]) < 0)
606		return;
607
 
 
 
 
608	/* urb is now ready to submit */
609	for (i = 0; i < priv->num_urbs; i++) {
610		if (!is_tweaked) {
611			ret = usb_submit_urb(priv->urbs[i], GFP_KERNEL);
612
613			if (ret == 0)
614				usbip_dbg_stub_rx("submit urb ok, seqnum %u\n",
615						pdu->base.seqnum);
616			else {
617				dev_err(&udev->dev, "submit_urb error, %d\n", ret);
618				usbip_dump_header(pdu);
619				usbip_dump_urb(priv->urbs[i]);
620
621				/*
622				 * Pessimistic.
623				 * This connection will be discarded.
624				 */
625				usbip_event_add(ud, SDEV_EVENT_ERROR_SUBMIT);
626				break;
627			}
628		} else {
629			/*
630			 * An identical URB was already submitted in
631			 * tweak_special_requests(). Skip submitting this URB to not
632			 * duplicate the request.
633			 */
634			priv->urbs[i]->status = 0;
635			stub_complete(priv->urbs[i]);
636		}
637	}
638
639	usbip_dbg_stub_rx("Leave\n");
640	return;
641
642err_urb:
643	kfree(priv->urbs);
644err_urbs:
645	kfree(buffer);
646	sgl_free(sgl);
647err_malloc:
648	usbip_event_add(ud, SDEV_EVENT_ERROR_MALLOC);
649}
650
651/* recv a pdu */
652static void stub_rx_pdu(struct usbip_device *ud)
653{
654	int ret;
655	struct usbip_header pdu;
656	struct stub_device *sdev = container_of(ud, struct stub_device, ud);
657	struct device *dev = &sdev->udev->dev;
658
659	usbip_dbg_stub_rx("Enter\n");
660
661	memset(&pdu, 0, sizeof(pdu));
662
663	/* receive a pdu header */
664	ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu));
665	if (ret != sizeof(pdu)) {
666		dev_err(dev, "recv a header, %d\n", ret);
667		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
668		return;
669	}
670
671	usbip_header_correct_endian(&pdu, 0);
672
673	if (usbip_dbg_flag_stub_rx)
674		usbip_dump_header(&pdu);
675
676	if (!valid_request(sdev, &pdu)) {
677		dev_err(dev, "recv invalid request\n");
678		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
679		return;
680	}
681
682	switch (pdu.base.command) {
683	case USBIP_CMD_UNLINK:
684		stub_recv_cmd_unlink(sdev, &pdu);
685		break;
686
687	case USBIP_CMD_SUBMIT:
688		stub_recv_cmd_submit(sdev, &pdu);
689		break;
690
691	default:
692		/* NOTREACHED */
693		dev_err(dev, "unknown pdu\n");
694		usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
695		break;
696	}
697}
698
699int stub_rx_loop(void *data)
700{
701	struct usbip_device *ud = data;
702
703	while (!kthread_should_stop()) {
704		if (usbip_event_happened(ud))
705			break;
706
707		stub_rx_pdu(ud);
708	}
709
710	return 0;
711}