ffmpeg | branch: master | Michael Niedermayer <mich...@niedermayer.cc> | Thu May 11 19:10:16 2017 +0200| [15e892aad12b23e9b5686cf66ca6fa739c734ead] | committer: Michael Niedermayer
avcodec/msmpeg4dec: Check for cbpy VLC errors Fixes: runtime error: left shift of negative value -1 Fixes: 1480/clusterfuzz-testcase-minimized-5188321007370240 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=15e892aad12b23e9b5686cf66ca6fa739c734ead --- libavcodec/msmpeg4dec.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/libavcodec/msmpeg4dec.c b/libavcodec/msmpeg4dec.c index b5bc36ece2..4105d4ba7d 100644 --- a/libavcodec/msmpeg4dec.c +++ b/libavcodec/msmpeg4dec.c @@ -169,12 +169,23 @@ static int msmpeg4v12_decode_mb(MpegEncContext *s, int16_t block[6][64]) s->mv[0][0][1] = my; *mb_type_ptr = MB_TYPE_L0 | MB_TYPE_16x16; } else { + int v; if(s->msmpeg4_version==2){ s->ac_pred = get_bits1(&s->gb); - cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors + v = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); + if (v < 0) { + av_log(s->avctx, AV_LOG_ERROR, "cbpy vlc invalid\n"); + return -1; + } + cbp|= v<<2; } else{ s->ac_pred = 0; - cbp|= get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1)<<2; //FIXME check errors + v = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1); + if (v < 0) { + av_log(s->avctx, AV_LOG_ERROR, "cbpy vlc invalid\n"); + return -1; + } + cbp|= v<<2; if(s->pict_type==AV_PICTURE_TYPE_P) cbp^=0x3C; } *mb_type_ptr = MB_TYPE_INTRA; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
