[FFmpeg-cvslog] avcodec/g723_1dec: Fix runtime error: left shift of negative value -1

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Fri May 12 13:13:46 2017 +0200| [c4c0245686bc2fcc545644101c7b328fed71f268] | committer: Michael Niedermayer

avcodec/g723_1dec: Fix runtime error: left shift of negative value -1

Fixes: 1504/clusterfuzz-testcase-minimized-6249212138225664

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=c4c0245686bc2fcc545644101c7b328fed71f268
---

 libavcodec/g723_1dec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/g723_1dec.c b/libavcodec/g723_1dec.c
index 6d452df189..89089f5f64 100644
--- a/libavcodec/g723_1dec.c
+++ b/libavcodec/g723_1dec.c
@@ -695,13 +695,13 @@ static int estimate_sid_gain(G723_1_Context *p)
     if (y <= 0) {
         t = seg * 32 + (val + 1 << seg2);
         t = t * t - x;
-        val = (seg2 - 1 << 4) + val;
+        val = (seg2 - 1) * 16 + val;
         if (t >= y)
             val++;
     } else {
         t = seg * 32 + (val - 1 << seg2);
         t = t * t - x;
-        val = (seg2 - 1 << 4) + val;
+        val = (seg2 - 1) * 16 + val;
         if (t >= y)
             val--;
     }