From 638a151a877c27a46c15643db26c9ba726feecde Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 14 Jan 2021 18:41:41 +0100 Subject: [PATCH] avformat/bfi: Check chunk_header Fixes: signed integer overflow: -2147483648 - 3 cannot be represented in type 'int' Fixes: 26910/clusterfuzz-testcase-minimized-ffmpeg_dem_BFI_fuzzer-6665764123836416 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavformat/bfi.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavformat/bfi.c b/libavformat/bfi.c index 29e2cf8cf4..2dab986f3a 100644 --- a/libavformat/bfi.c +++ b/libavformat/bfi.c @@ -69,6 +69,9 @@ static int bfi_read_header(AVFormatContext * s) /* Set the total number of frames. */ avio_skip(pb, 8); chunk_header = avio_rl32(pb); + if (chunk_header < 3) + return AVERROR_INVALIDDATA; + bfi->nframes = avio_rl32(pb); avio_rl32(pb); avio_rl32(pb);