On Wed, Sep 10, 2014 at 06:51:09PM +0200, Maciej Matraszek wrote: > Fix clamp_align() used in v4l_bound_align_image() to prevent overflow when > passed large value like UINT32_MAX. In the current implementation: > clamp_align(UINT32_MAX, 8, 8192, 3) > returns 8, because in line: > x = (x + (1 << (align - 1))) & mask; > x overflows to (-1 + 4) & 0x7 = 3, while expected value is 8192. > > v4l_bound_align_image() is heavily used in VIDIOC_S_FMT > and VIDIOC_SUBDEV_S_FMT ioctls handlers, and documentation of the latter > explicitly states that: > > "The modified format should be as close as possible to the original request." > -- http://linuxtv.org/downloads/v4l-dvb-apis/vidioc-subdev-g-fmt.html > > Thus one would expect, that passing UINT32_MAX as format width and height > will result in setting maximum possible resolution for the device. > Particularly, when the driver doesn't support VIDIOC_ENUM_FRAMESIZES ioctl, > which is common in the codebase. > > Fixes: b0d3159be9a3 ("V4L/DVB (11901): v4l2: Create helper function for bounding and aligning images") > Signed-off-by: Maciej Matraszek <m.matraszek@xxxxxxxxxxx> > Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > > --- <formletter> This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read Documentation/stable_kernel_rules.txt for how to do this properly. </formletter> -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
