[FFmpeg-cvslog] avcodec/snowdec: Check width

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Tue May  9 16:08:14 2017 +0200| [78aa93807b3e0674e34d32c0bf6f78d7f5b7927e] | committer: Michael Niedermayer

avcodec/snowdec: Check width

Fixes: out of array read
Fixes: 1419/clusterfuzz-testcase-minimized-6108700873850880

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=78aa93807b3e0674e34d32c0bf6f78d7f5b7927e
---

 libavcodec/snowdec.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c
index 8c35e3e084..bcb3469062 100644
--- a/libavcodec/snowdec.c
+++ b/libavcodec/snowdec.c
@@ -384,6 +384,10 @@ static int decode_header(SnowContext *s){
         av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_count %d too large for size\n", s->spatial_decomposition_count);
         return AVERROR_INVALIDDATA;
     }
+    if (s->avctx->width > 65536-4) {
+        av_log(s->avctx, AV_LOG_ERROR, "Width %d is too large\n", s->avctx->width);
+        return AVERROR_INVALIDDATA;
+    }
 
 
     s->qlog           += get_symbol(&s->c, s->header_state, 1);