3.16.51-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Daniel Mentz <[email protected]> commit 9c7ba1d7634cef490b85bc64c4091ff004821bfd upstream. Certain syscalls like recvmmsg support 64 bit timespec values for the X32 ABI. The helper function compat_put_timespec converts a timespec value to a 32 bit or 64 bit value depending on what ABI is used. The v4l2 compat layer, however, is not designed to support 64 bit timespec values and always uses 32 bit values. Hence, compat_put_timespec must not be used. Without this patch, user space will be provided with bad timestamp values from the VIDIOC_DQEVENT ioctl. Also, fields of the struct v4l2_event32 that come immediately after timestamp get overwritten, namely the field named id. Fixes: 81993e81a994 ("compat: Get rid of (get|put)_compat_time(val|spec)") Cc: H. Peter Anvin <[email protected]> Cc: Laurent Pinchart <[email protected]> Cc: Tiffany Lin <[email protected]> Cc: Ricardo Ribalda Delgado <[email protected]> Cc: Sakari Ailus <[email protected]> Signed-off-by: Daniel Mentz <[email protected]> Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- drivers/media/v4l2-core/v4l2-compat-ioctl32.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/media/v4l2-core/v4l2-compat-ioctl32.c +++ b/drivers/media/v4l2-core/v4l2-compat-ioctl32.c @@ -731,7 +731,8 @@ static int put_v4l2_event32(struct v4l2_ copy_to_user(&up->u, &kp->u, sizeof(kp->u)) || put_user(kp->pending, &up->pending) || put_user(kp->sequence, &up->sequence) || - compat_put_timespec(&kp->timestamp, &up->timestamp) || + put_user(kp->timestamp.tv_sec, &up->timestamp.tv_sec) || + put_user(kp->timestamp.tv_nsec, &up->timestamp.tv_nsec) || put_user(kp->id, &up->id) || copy_to_user(up->reserved, kp->reserved, 8 * sizeof(__u32))) return -EFAULT;
