[FFmpeg-cvslog] golomb: check log validity before shifting

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Sat Jan 12 22:14:25 2013 +0100| [fd165ace7b2791af75c74652364d47957d4ea932] | committer: Michael Niedermayer

golomb: check log validity before shifting

Fixes invalid right shift in fate-cavs

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fd165ace7b2791af75c74652364d47957d4ea932
---

 libavcodec/golomb.h |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/libavcodec/golomb.h b/libavcodec/golomb.h
index 0629c78..9f82c74 100644
--- a/libavcodec/golomb.h
+++ b/libavcodec/golomb.h
@@ -66,10 +66,14 @@ static inline int get_ue_golomb(GetBitContext *gb){
         return ff_ue_golomb_vlc_code[buf];
     }else{
         log= 2*av_log2(buf) - 31;
-        buf>>= log;
-        buf--;
         LAST_SKIP_BITS(re, gb, 32 - log);
         CLOSE_READER(re, gb);
+        if (CONFIG_FTRAPV && log < 0) {
+            av_log(0, AV_LOG_ERROR, "Invalid UE golomb code\n");
+            return AVERROR_INVALIDDATA;
+        }
+        buf>>= log;
+        buf--;
 
         return buf;
     }