From 2ecaef745556684ba3d446994a570214e6fac7ce Mon Sep 17 00:00:00 2001 From: James Almer Date: Mon, 1 Apr 2024 21:13:04 -0300 Subject: [PATCH] avformat/mov: ensure all items id referenced by a grid are valid Fixes: null pointer dereference Fixes: 67494/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-6528714521247744 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Tested-by: Michael Niedermayer Signed-off-by: James Almer --- libavformat/mov.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/libavformat/mov.c b/libavformat/mov.c index c93a09d385..917a69fa34 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -9396,8 +9396,9 @@ static int mov_parse_tiles(AVFormatContext *s) for (int j = 0; j < grid->nb_tiles; j++) { int tile_id = grid->tile_id_list[j]; + int k; - for (int k = 0; k < mov->nb_heif_item; k++) { + for (k = 0; k < mov->nb_heif_item; k++) { HEIFItem *item = &mov->heif_item[k]; AVStream *st = item->st; @@ -9423,6 +9424,13 @@ static int mov_parse_tiles(AVFormatContext *s) break; } + if (k == grid->nb_tiles) { + av_log(s, AV_LOG_WARNING, "HEIF item id %d referenced by grid id %d doesn't " + "exist\n", + tile_id, grid->item->item_id); + ff_remove_stream_group(s, stg); + loop = 0; + } if (!loop) break; }