On 12/13/18 11:40 AM, Sakari Ailus wrote:
> PAGE_ALIGN() may wrap the buffer size around to 0. Prevent this by
> checking that the aligned value is not smaller than the unaligned one.
>
> Note on backporting to stable: the file used to be under
> drivers/media/v4l2-core, it was moved to the current location after 4.14.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Regards,
Hans
> ---
> drivers/media/common/videobuf2/videobuf2-core.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index 0ca81d495bdaf..0234ddbfa4de2 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -207,6 +207,10 @@ static int __vb2_buf_mem_alloc(struct vb2_buffer *vb)
> for (plane = 0; plane < vb->num_planes; ++plane) {
> unsigned long size = PAGE_ALIGN(vb->planes[plane].length);
>
> + /* Did it wrap around? */
> + if (size < vb->planes[plane].length)
> + goto free;
> +
> mem_priv = call_ptr_memop(vb, alloc,
> q->alloc_devs[plane] ? : q->dev,
> q->dma_attrs, size, q->dma_dir, q->gfp_flags);
>
