6.1-stable patches

added patches:
	media-uvcvideo-fix-race-condition-with-usb_kill_urb.patch

diff --git a/queue-6.1/media-uvcvideo-fix-race-condition-with-usb_kill_urb.patch b/queue-6.1/media-uvcvideo-fix-race-condition-with-usb_kill_urb.patch
new file mode 100644 (file)
index 0000000..f9e71d5
--- /dev/null
+++ b/queue-6.1/media-uvcvideo-fix-race-condition-with-usb_kill_urb.patch
@@ -0,0 +1,140 @@
+From 619d9b710cf06f7a00a17120ca92333684ac45a8 Mon Sep 17 00:00:00 2001
+From: Ricardo Ribalda <ribalda@chromium.org>
+Date: Thu, 5 Jan 2023 15:31:29 +0100
+Subject: media: uvcvideo: Fix race condition with usb_kill_urb
+
+From: Ricardo Ribalda <ribalda@chromium.org>
+
+commit 619d9b710cf06f7a00a17120ca92333684ac45a8 upstream.
+
+usb_kill_urb warranties that all the handlers are finished when it
+returns, but does not protect against threads that might be handling
+asynchronously the urb.
+
+For UVC, the function uvc_ctrl_status_event_async() takes care of
+control changes asynchronously.
+
+If the code is executed in the following order:
+
+CPU 0                                  CPU 1
+=====                                  =====
+uvc_status_complete()
+                                       uvc_status_stop()
+uvc_ctrl_status_event_work()
+                                       uvc_status_start() -> FAIL
+
+Then uvc_status_start will keep failing and this error will be shown:
+
+<4>[    5.540139] URB 0000000000000000 submitted while active
+drivers/usb/core/urb.c:378 usb_submit_urb+0x4c3/0x528
+
+Let's improve the current situation, by not re-submiting the urb if
+we are stopping the status event. Also process the queued work
+(if any) during stop.
+
+CPU 0                                  CPU 1
+=====                                  =====
+uvc_status_complete()
+                                       uvc_status_stop()
+                                       uvc_status_start()
+uvc_ctrl_status_event_work() -> FAIL
+
+Hopefully, with the usb layer protection this should be enough to cover
+all the cases.
+
+Cc: stable@vger.kernel.org
+Fixes: e5225c820c05 ("media: uvcvideo: Send a control event when a Control Change interrupt arrives")
+Reviewed-by: Yunke Cao <yunkec@chromium.org>
+Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
+Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/media/usb/uvc/uvc_ctrl.c   |    5 +++++
+ drivers/media/usb/uvc/uvc_status.c |   37 +++++++++++++++++++++++++++++++++++++
+ drivers/media/usb/uvc/uvcvideo.h   |    1 +
+ 3 files changed, 43 insertions(+)
+
+--- a/drivers/media/usb/uvc/uvc_ctrl.c
++++ b/drivers/media/usb/uvc/uvc_ctrl.c
+@@ -6,6 +6,7 @@
+  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+  */
+ 
++#include <asm/barrier.h>
+ #include <linux/bitops.h>
+ #include <linux/kernel.h>
+ #include <linux/list.h>
+@@ -1509,6 +1510,10 @@ static void uvc_ctrl_status_event_work(s
+ 
+       uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
+ 
++      /* The barrier is needed to synchronize with uvc_status_stop(). */
++      if (smp_load_acquire(&dev->flush_status))
++              return;
++
+       /* Resubmit the URB. */
+       w->urb->interval = dev->int_ep->desc.bInterval;
+       ret = usb_submit_urb(w->urb, GFP_KERNEL);
+--- a/drivers/media/usb/uvc/uvc_status.c
++++ b/drivers/media/usb/uvc/uvc_status.c
+@@ -6,6 +6,7 @@
+  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+  */
+ 
++#include <asm/barrier.h>
+ #include <linux/kernel.h>
+ #include <linux/input.h>
+ #include <linux/slab.h>
+@@ -309,5 +310,41 @@ int uvc_status_start(struct uvc_device *
+ 
+ void uvc_status_stop(struct uvc_device *dev)
+ {
++      struct uvc_ctrl_work *w = &dev->async_ctrl;
++
++      /*
++       * Prevent the asynchronous control handler from requeing the URB. The
++       * barrier is needed so the flush_status change is visible to other
++       * CPUs running the asynchronous handler before usb_kill_urb() is
++       * called below.
++       */
++      smp_store_release(&dev->flush_status, true);
++
++      /*
++       * Cancel any pending asynchronous work. If any status event was queued,
++       * process it synchronously.
++       */
++      if (cancel_work_sync(&w->work))
++              uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
++
++      /* Kill the urb. */
+       usb_kill_urb(dev->int_urb);
++
++      /*
++       * The URB completion handler may have queued asynchronous work. This
++       * won't resubmit the URB as flush_status is set, but it needs to be
++       * cancelled before returning or it could then race with a future
++       * uvc_status_start() call.
++       */
++      if (cancel_work_sync(&w->work))
++              uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
++
++      /*
++       * From this point, there are no events on the queue and the status URB
++       * is dead. No events will be queued until uvc_status_start() is called.
++       * The barrier is needed to make sure that flush_status is visible to
++       * uvc_ctrl_status_event_work() when uvc_status_start() will be called
++       * again.
++       */
++      smp_store_release(&dev->flush_status, false);
+ }
+--- a/drivers/media/usb/uvc/uvcvideo.h
++++ b/drivers/media/usb/uvc/uvcvideo.h
+@@ -558,6 +558,7 @@ struct uvc_device {
+       /* Status Interrupt Endpoint */
+       struct usb_host_endpoint *int_ep;
+       struct urb *int_urb;
++      bool flush_status;
+       u8 *status;
+       struct input_dev *input;
+       char input_phys[64];

diff --git a/queue-6.1/series b/queue-6.1/series
index 78a84ec43ea27164f9ab7ad40a820f404ebc018d..0fa60d40b7504baecb46a2b7b4b2ff440cfa42bd 100644 (file)
--- a/queue-6.1/series
+++ b/queue-6.1/series
@@ -191,3 +191,4 @@ drm-display-dp_mst-fix-down-message-handling-after-a-packet-reception-error.patc
 drm-display-dp_mst-fix-payload-addition-on-a-disconnected-sink.patch
 drm-i915-dp_mst-add-the-mst-topology-state-for-modesetted-crtcs.patch
 drm-i915-fix-system-suspend-without-fbdev-being-initialized.patch
+media-uvcvideo-fix-race-condition-with-usb_kill_urb.patch