[FFmpeg-devel] [PATCH 1/3] avcodec/clearvideo: Check tile_size to be not too large

Michael Niedermayer michael at niedermayer.cc
Tue Jun 22 00:25:42 EEST 2021


Fixes: left shift of 1 by 31 places cannot be represented in type 'int'
Fixes: 35023/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CLEARVIDEO_fuzzer-6740166587842560

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/clearvideo.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/clearvideo.c b/libavcodec/clearvideo.c
index 5c79376c64..5ed8ac71dc 100644
--- a/libavcodec/clearvideo.c
+++ b/libavcodec/clearvideo.c
@@ -722,8 +722,8 @@ static av_cold int clv_decode_init(AVCodecContext *avctx)
     }
 
     c->tile_shift = av_log2(c->tile_size);
-    if (1U << c->tile_shift != c->tile_size || c->tile_shift < 1) {
-        av_log(avctx, AV_LOG_ERROR, "Tile size: %d, is not power of 2 > 1\n", c->tile_size);
+    if (1U << c->tile_shift != c->tile_size || c->tile_shift < 1 || c->tile_shift > 30) {
+        av_log(avctx, AV_LOG_ERROR, "Tile size: %d, is not power of 2 > 1 and < 2^31\n", c->tile_size);
         return AVERROR_INVALIDDATA;
     }
 
-- 
2.17.1



More information about the ffmpeg-devel mailing list