[FFmpeg-cvslog] avcodec/alsdec: Fix undefined behavior in decode_rice()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Wed Jun 19 23:17:31 2019 +0200| [51f6870c37cc29e1ea7e0c66df2fe505938b7561] | committer: Michael Niedermayer

avcodec/alsdec: Fix undefined behavior in decode_rice()

Fixes: left shift of 72 by 26 places cannot be represented in type 'int'
Fixes: 15279/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALS_fuzzer-5700665621348352

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=51f6870c37cc29e1ea7e0c66df2fe505938b7561
---

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

diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c
index 2660747472..e54440910c 100644
--- a/libavcodec/alsdec.c
+++ b/libavcodec/alsdec.c
@@ -487,7 +487,7 @@ static void parse_bs_info(const uint32_t bs_info, unsigned int n,
 static int32_t decode_rice(GetBitContext *gb, unsigned int k)
 {
     int max = get_bits_left(gb) - k;
-    int q   = get_unary(gb, 0, max);
+    unsigned q = get_unary(gb, 0, max);
     int r   = k ? get_bits1(gb) : !(q & 1);
 
     if (k > 1) {