[FFmpeg-devel] [PATCH 3/4] avcodec/g723_1dec: fix invalid shift with negative sid_gain

Michael Niedermayer michael at niedermayer.cc
Sun Oct 27 02:15:46 EEST 2019


Fixes: left shift of negative value -1
Fixes: 18395/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G723_1_fuzzer-5710313034350592

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/g723_1dec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/g723_1dec.c b/libavcodec/g723_1dec.c
index a7bf528470..f601d31d00 100644
--- a/libavcodec/g723_1dec.c
+++ b/libavcodec/g723_1dec.c
@@ -677,7 +677,7 @@ static int estimate_sid_gain(G723_1_ChannelContext *p)
             if (p->sid_gain < 0) t = INT32_MIN;
             else                 t = INT32_MAX;
         } else
-            t = p->sid_gain << shift;
+            t = p->sid_gain * (1 << shift);
     } else if(shift < -31) {
         t = (p->sid_gain < 0) ? -1 : 0;
     }else
-- 
2.23.0



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