Re: [PATCH v3 03/11] media: videobuf2: Remove VB2_MAX_FRAME limit on buffer storage

[Dan Carpenter]

On Thu, Jun 22, 2023 at 03:13:41PM +0200, Benjamin Gaignard wrote:
> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index f1ff7af34a9f..86e1e926fa45 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -455,9 +455,9 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
>  	struct vb2_buffer *vb;
>  	int ret;
>  
> -	/* Ensure that q->num_buffers+num_buffers is below VB2_MAX_FRAME */
> +	/* Ensure that q->num_buffers + num_buffers is UINT_MAX */
>  	num_buffers = min_t(unsigned int, num_buffers,
> -			    VB2_MAX_FRAME - q->num_buffers);
> +			    UINT_MAX - q->num_buffers);
>  
>  	for (buffer = 0; buffer < num_buffers; ++buffer) {
>  		/* Allocate vb2 buffer structures */

Ah...  Here's one of the integer overflow bugs I was talking about.  The
__vb2_queue_alloc() function returns an int so if num_buffers goes over
INT_MAX we are hosed.

regards,
dan carpenter