avcodec/mlp_parser: Check if synccode is within buffer
authorMichael Niedermayer <michael@niedermayer.cc>
Sun, 29 Jul 2018 11:16:37 +0000 (13:16 +0200)
committerMichael Niedermayer <michael@niedermayer.cc>
Fri, 3 Aug 2018 00:08:16 +0000 (02:08 +0200)
Fixes: undefined shift
Fixes: 9216/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TRUEHD_fuzzer-6281404575907840

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

index 185bd4d..eb3435b 100644 (file)
@@ -320,7 +320,7 @@ static int mlp_parse(AVCodecParserContext *s,
         mp->bytes_left = 0;
     }
 
-    sync_present = (AV_RB32(buf + 4) & 0xfffffffe) == 0xf8726fba;
+    sync_present = buf_size >= 8 && (AV_RB32(buf + 4) & 0xfffffffe) == 0xf8726fba;
 
     if (!sync_present) {
         /* The first nibble of a frame is a parity check of the 4-byte