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  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