[FFmpeg-cvslog] avcodec/aacdec_fixed: Fix runtime error: shift exponent 34 is too large for 32-bit type 'int'

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sun May 21 16:53:55 2017 +0200| [b5228e44c7f3a5eba537c8a39a45cfbf2961a28d] | committer: Michael Niedermayer

avcodec/aacdec_fixed: Fix runtime error: shift exponent 34 is too large for 32-bit type 'int'

Fixes: 1721/clusterfuzz-testcase-minimized-4719352135811072

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

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b5228e44c7f3a5eba537c8a39a45cfbf2961a28d
---

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

diff --git a/libavcodec/aacdec_fixed.c b/libavcodec/aacdec_fixed.c
index b416cf1d25..7b5e40e484 100644
--- a/libavcodec/aacdec_fixed.c
+++ b/libavcodec/aacdec_fixed.c
@@ -207,7 +207,11 @@ static void noise_scale(int *coefs, int scale, int band_energy, int len)
     c /= band_energy;
     s = 21 + nlz - (s >> 2);
 
-    if (s > 0) {
+    if (s > 31) {
+        for (i=0; i<len; i++) {
+            coefs[i] = 0;
+        }
+    } else if (s > 0) {
         round = 1 << (s-1);
         for (i=0; i<len; i++) {
             out = (int)(((int64_t)coefs[i] * c) >> 32);