Skip to content
  1. Jan 22, 2023
  3. Jan 16, 2023
    • Kees Cook's avatar
      media: uvcvideo: Silence memcpy() run-time false positive warnings · b8392129
      Kees Cook authored 
      

The memcpy() in uvc_video_decode_meta() intentionally copies across the
length and flags members and into the trailing buf flexible array.
Split the copy so that the compiler can better reason about (the lack
of) buffer overflows here. Avoid the run-time false positive warning:

  memcpy: detected field-spanning write (size 12) of single field "&meta->length" at drivers/media/usb/uvc/uvc_video.c:1355 (size 1)

Additionally fix a typo in the documentation for struct uvc_meta_buf.

Reported-by: default avatar <ionut_n2001@yahoo.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216810


Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
      b8392129
    • Ricardo Ribalda's avatar
      media: uvcvideo: Quirk for autosuspend in Logitech B910 and C910 · 136effa7
      Ricardo Ribalda authored 
      

Logitech B910 and C910 firmware are unable to recover from a USB
autosuspend. When it resumes, the device is in a state where it only
produces invalid frames. Eg:

$ echo 0xFFFF > /sys/module/uvcvideo/parameters/trace # enable verbose log
$ yavta -c1 -n1 --file='frame#.jpg' --format MJPEG --size=1920x1080 /dev/video1
[350438.435219] uvcvideo: uvc_v4l2_open
[350438.529794] uvcvideo: Resuming interface 2
[350438.529801] uvcvideo: Resuming interface 3
[350438.529991] uvcvideo: Trying format 0x47504a4d (MJPG): 1920x1080.
[350438.529996] uvcvideo: Using default frame interval 33333.3 us (30.0 fps).
[350438.551496] uvcvideo: uvc_v4l2_mmap
[350438.555890] uvcvideo: Device requested 3060 B/frame bandwidth.
[350438.555896] uvcvideo: Selecting alternate setting 11 (3060 B/frame bandwidth).
[350438.556362] uvcvideo: Allocated 5 URB buffers of 32x3060 bytes each.
[350439.316468] uvcvideo: Marking buffer as bad (error bit set).
[350439.316475] uvcvideo: Frame complete (EOF found).
[350439.316477] uvcvideo: EOF in empty payload.
[350439.316484] uvcvideo: frame 1 stats: 149/261/417 packets, 1/149/417 pts (early initial), 416/417 scr, last pts/stc/sof 2976325734/2978107243/249
[350439.384510] uvcvideo: Marking buffer as bad (error bit set).
[350439.384516] uvcvideo: Frame complete (EOF found).
[350439.384518] uvcvideo: EOF in empty payload.
[350439.384525] uvcvideo: frame 2 stats: 265/379/533 packets, 1/265/533 pts (early initial), 532/533 scr, last pts/stc/sof 2979524454/2981305193/316
[350439.448472] uvcvideo: Marking buffer as bad (error bit set).
[350439.448478] uvcvideo: Frame complete (EOF found).
[350439.448480] uvcvideo: EOF in empty payload.
[350439.448487] uvcvideo: frame 3 stats: 265/377/533 packets, 1/265/533 pts (early initial), 532/533 scr, last pts/stc/sof 2982723174/2984503144/382
...(loop)...

The devices can leave this invalid state if the alternate setting of
the streaming interface is toggled.

This patch adds a quirk for this device so it can be autosuspended
properly.

lsusb -v:
Bus 001 Device 049: ID 046d:0821 Logitech, Inc. HD Webcam C910
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0        64
  idVendor           0x046d Logitech, Inc.
  idProduct          0x0821 HD Webcam C910
  bcdDevice            0.10
  iManufacturer           0
  iProduct                0
  iSerial                 1 390022B0
  bNumConfigurations      1

Signed-off-by: default avatarRicardo Ribalda <ribalda@chromium.org>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
      136effa7
    • Ricardo Ribalda's avatar
      media: uvcvideo: Fix race condition with usb_kill_urb · 619d9b71
      Ricardo Ribalda authored 
      

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: e5225c82 ("media: uvcvideo: Send a control event when a Control Change interrupt arrives")
Reviewed-by: default avatarYunke Cao <yunkec@chromium.org>
Signed-off-by: default avatarRicardo Ribalda <ribalda@chromium.org>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
      619d9b71