[FFmpeg-cvslog] avcodec/g723_1dec: Clip bits2 in both directions

[Michael Niedermayer]

ffmpeg | branch: release/3.3 | Michael Niedermayer <michael at niedermayer.cc> | Fri May 25 21:56:04 2018 +0200| [45ce622f909354847bbbab9b650b2264d33f2d58] | committer: Michael Niedermayer

avcodec/g723_1dec: Clip bits2 in both directions

Fixes: shift exponent 33 is too large for 32-bit type 'int'
Fixes: 6743/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G723_1_fuzzer-5823772687859712

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 53f241218d9eac368e2e1c58bcca9bbdf10fd0e1)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=45ce622f909354847bbbab9b650b2264d33f2d58
---

 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 aaa26c24ef..3522c91bd6 100644
--- a/libavcodec/g723_1dec.c
+++ b/libavcodec/g723_1dec.c
@@ -549,7 +549,7 @@ static void gain_scale(G723_1_Context *p, int16_t * buf, int energy)
         denom <<= bits2;
 
         bits2 = 5 + bits1 - bits2;
-        bits2 = FFMAX(0, bits2);
+        bits2 = av_clip_uintp2(bits2, 5);
 
         gain = (num >> 1) / (denom >> 16);
         gain = square_root(gain << 16 >> bits2);