avcodec/pngdec: dont skip/read chunk twice

Fixes: out of array access
Fixes: 48567/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PNG_fuzzer-6668158952144896.fuzz

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2023-01-11 23:56:05 +01:00
parent d5bae70406
commit df1a38d520
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1 changed files with 1 additions and 0 deletions

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@ -1238,6 +1238,7 @@ static int decode_frame_common(AVCodecContext *avctx, PNGDecContext *s,
}
av_log(avctx, AV_LOG_ERROR, ", skipping\n");
bytestream2_skip(&s->gb, length + 8); /* tag */
continue;
}
}
tag = bytestream2_get_le32(&s->gb);