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| author | Maciej Matraszek <m.matraszek@samsung.com> | 2014-09-15 05:14:48 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2014-09-23 16:13:43 -0300 |
| commit | 3bacc10cd4a85bc70bc0b6c001d3bf995c7fe04c (patch) | |
| tree | eba9c1053dacf1e0aadd3148d7c0b1e9191394b9 /drivers/media | |
| parent | 43c3ea312c49efa01dc3b6cd5d78dd8bed27f347 (diff) | |
| download | linux-3bacc10cd4a85bc70bc0b6c001d3bf995c7fe04c.tar.bz2 | |
[media] v4l2-common: fix overflow in v4l_bound_align_image()
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 changeset: b0d3159be9a3
Signed-off-by: Maciej Matraszek <m.matraszek@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-common.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c index ccaa38f65cf1..2e9d81f4c1a5 100644 --- a/drivers/media/v4l2-core/v4l2-common.c +++ b/drivers/media/v4l2-core/v4l2-common.c @@ -435,16 +435,13 @@ static unsigned int clamp_align(unsigned int x, unsigned int min, /* Bits that must be zero to be aligned */ unsigned int mask = ~((1 << align) - 1); + /* Clamp to aligned min and max */ + x = clamp(x, (min + ~mask) & mask, max & mask); + /* Round to nearest aligned value */ if (align) x = (x + (1 << (align - 1))) & mask; - /* Clamp to aligned value of min and max */ - if (x < min) - x = (min + ~mask) & mask; - else if (x > max) - x = max & mask; - return x; } |