[FFmpeg-devel] [PATCH] avcodec/zmbv: Check decomp_size

Michael Niedermayer michael at niedermayer.cc
Wed Aug 16 06:04:42 EEST 2017


Fixes: OOM
Fixes: 2710/clusterfuzz-testcase-minimized-4750001420894208

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/zmbv.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libavcodec/zmbv.c b/libavcodec/zmbv.c
index f126515bd1..861098a0f2 100644
--- a/libavcodec/zmbv.c
+++ b/libavcodec/zmbv.c
@@ -589,8 +589,12 @@ static av_cold int decode_init(AVCodecContext *avctx)
     // Needed if zlib unused or init aborted before inflateInit
     memset(&c->zstream, 0, sizeof(z_stream));
 
-    c->decomp_size = (avctx->width + 255) * 4 * (avctx->height + 64);
+    if ((avctx->width + 255ULL) * (avctx->height + 64ULL) > avctx->max_pixels) {
+        av_log(avctx, AV_LOG_ERROR, "Internal buffer larger than max_pixels\n");
+        return AVERROR_INVALIDDATA;
+    }
 
+    c->decomp_size = (avctx->width + 255) * 4 * (avctx->height + 64);
     /* Allocate decompression buffer */
     if (c->decomp_size) {
         if (!(c->decomp_buf = av_mallocz(c->decomp_size))) {
-- 
2.14.1



More information about the ffmpeg-devel mailing list