[FFmpeg-devel] [PATCH 3/3] avcodec/qdm2: Check checksum_size for 0

[Michael Niedermayer]

Fixes: Infinite loop
Fixes: 15337/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_QDM2_fuzzer-5757428949319680

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/qdm2.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/qdm2.c b/libavcodec/qdm2.c
index 42e10829e9..05519d61a4 100644
--- a/libavcodec/qdm2.c
+++ b/libavcodec/qdm2.c
@@ -1703,8 +1703,8 @@ static av_cold int qdm2_decode_init(AVCodecContext *avctx)
     s->group_size = bytestream2_get_be32(&gb);
     s->fft_size = bytestream2_get_be32(&gb);
     s->checksum_size = bytestream2_get_be32(&gb);
-    if (s->checksum_size >= 1U << 28) {
-        av_log(avctx, AV_LOG_ERROR, "data block size too large (%u)\n", s->checksum_size);
+    if (s->checksum_size >= 1U << 28 || !s->checksum_size) {
+        av_log(avctx, AV_LOG_ERROR, "data block size invalid (%u)\n", s->checksum_size);
         return AVERROR_INVALIDDATA;
     }
 
-- 
2.22.0