[FFmpeg-devel] [PATCH 2/3] avformat/mov: Do not deallocate heif_item in a input dependant way

[James Almer]

On 3/22/2024 8:08 PM, Michael Niedermayer wrote:
> Fixes: out of array access
> Fixes: 67070/clusterfuzz-testcase-minimized-ffmpeg_IO_DEMUXER_fuzzer-5685384082161664
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> ---
>   libavformat/mov.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index f954b924a0..a87ce5cefe 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -8077,7 +8077,7 @@ static int mov_read_iloc(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>       }
>       item_count = (version < 2) ? avio_rb16(pb) : avio_rb32(pb);
>   
> -    heif_item = av_realloc_array(c->heif_item, item_count, sizeof(*c->heif_item));
> +    heif_item = av_realloc_array(c->heif_item, FFMAX(item_count, c->nb_heif_item), sizeof(*c->heif_item));
>       if (!heif_item)
>           return AVERROR(ENOMEM);
>       c->heif_item = heif_item;
> @@ -8202,7 +8202,7 @@ static int mov_read_iinf(MOVContext *c, AVIOContext *pb, MOVAtom atom)
>       avio_rb24(pb);  // flags.
>       entry_count = version ? avio_rb32(pb) : avio_rb16(pb);
>   
> -    heif_item = av_realloc_array(c->heif_item, entry_count, sizeof(*c->heif_item));
> +    heif_item = av_realloc_array(c->heif_item, FFMAX(entry_count, c->nb_heif_item), sizeof(*c->heif_item));
>       if (!heif_item)
>           return AVERROR(ENOMEM);
>       c->heif_item = heif_item;

LGTM.