2023-10-12 07:46:30

by Ma Ke

Subject: [PATCH v2] media: videobuf2: Fix IS_ERR checking in vb2_dc_put_userptr()

In order to avoid error pointers from frame_vector_pages(), we could
use IS_ERR() to check the return value to fix this. This checking
operation could make sure that vector contains pages.

Signed-off-by: Ma Ke <[email protected]>
---
.../media/common/videobuf2/videobuf2-dma-contig.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
index 2fa455d4a048..3d4fd4ef5310 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
@@ -542,13 +542,14 @@ static void vb2_dc_put_userptr(void *buf_priv)
*/
dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,
DMA_ATTR_SKIP_CPU_SYNC);
- pages = frame_vector_pages(buf->vec);
- /* sgt should exist only if vector contains pages... */
- BUG_ON(IS_ERR(pages));
if (buf->dma_dir == DMA_FROM_DEVICE ||
- buf->dma_dir == DMA_BIDIRECTIONAL)
- for (i = 0; i < frame_vector_count(buf->vec); i++)
- set_page_dirty_lock(pages[i]);
+ buf->dma_dir == DMA_BIDIRECTIONAL) {
+ pages = frame_vector_pages(buf->vec);
+ /* sgt should exist only if vector contains pages... */
+ if (!WARN_ON_ONCE(IS_ERR(pages)))
+ for (i = 0; i < frame_vector_count(buf->vec); i++)
+ set_page_dirty_lock(pages[i]);
+ }
sg_free_table(sgt);
kfree(sgt);
} else {
--
2.37.2

2023-10-12 08:21:02

by Tomasz Figa

Subject: Re: [PATCH v2] media: videobuf2: Fix IS_ERR checking in vb2_dc_put_userptr()

On Thu, Oct 12, 2023 at 4:45 PM Ma Ke <[email protected]> wrote:
>
> In order to avoid error pointers from frame_vector_pages(), we could
> use IS_ERR() to check the return value to fix this. This checking
> operation could make sure that vector contains pages.
>
> Signed-off-by: Ma Ke <[email protected]>
> ---
> .../media/common/videobuf2/videobuf2-dma-contig.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> index 2fa455d4a048..3d4fd4ef5310 100644
> --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
> @@ -542,13 +542,14 @@ static void vb2_dc_put_userptr(void *buf_priv)
> */
> dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,
> DMA_ATTR_SKIP_CPU_SYNC);
> - pages = frame_vector_pages(buf->vec);
> - /* sgt should exist only if vector contains pages... */
> - BUG_ON(IS_ERR(pages));
> if (buf->dma_dir == DMA_FROM_DEVICE ||
> - buf->dma_dir == DMA_BIDIRECTIONAL)
> - for (i = 0; i < frame_vector_count(buf->vec); i++)
> - set_page_dirty_lock(pages[i]);
> + buf->dma_dir == DMA_BIDIRECTIONAL) {
> + pages = frame_vector_pages(buf->vec);
> + /* sgt should exist only if vector contains pages... */
> + if (!WARN_ON_ONCE(IS_ERR(pages)))
> + for (i = 0; i < frame_vector_count(buf->vec); i++)
> + set_page_dirty_lock(pages[i]);
> + }
> sg_free_table(sgt);
> kfree(sgt);
> } else {
> --
> 2.37.2
>

Thanks for fixing it up.

Acked-by: Tomasz Figa <[email protected]>

Best regards,
Tomasz