[FFmpeg-devel] [PATCH 5/5] avutil/frame: Use av_realloc_array(), improve overflow check

[Jan Ekström]

On Fri, Mar 22, 2024 at 4:41 PM Andreas Rheinhardt
<andreas.rheinhardt at outlook.com> wrote:
>
> Also use sizeof of the proper type, namely sizeof(**sd)
> and not sizeof(*sd).
>
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  libavutil/frame.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/libavutil/frame.c b/libavutil/frame.c
> index 7dd37e5490..d7a32cdc92 100644
> --- a/libavutil/frame.c
> +++ b/libavutil/frame.c
> @@ -721,10 +721,11 @@ static AVFrameSideData *add_side_data_from_buf(AVFrameSideData ***sd,
>      if (!buf)
>          return NULL;
>
> -    if (*nb_sd > INT_MAX / sizeof(*sd) - 1)
> +    // *nb_sd + 1 needs to fit into an int and a size_t.
> +    if ((unsigned)*nb_sd >= FFMIN(INT_MAX, SIZE_MAX))
>          return NULL;
>
> -    tmp = av_realloc(*sd, (*nb_sd + 1) * sizeof(*sd));
> +    tmp = av_realloc_array(*sd, sizeof(**sd), *nb_sd + 1);
>      if (!tmp)
>          return NULL;
>      *sd = tmp;
> --

Thanks for noticing these things like the AVClass-usage, figuring out
a workaround for the getter and improving on the overflow check as
well as doing the AVBPrint to snprintf switch.

Will have to think why I thought that AVClass thing was somehow a good idea.

Set LGTM.

Jan