diff options
author | Michael Niedermayer <michael@niedermayer.cc> | 2021-08-22 21:57:28 +0200 |
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committer | Michael Niedermayer <michael@niedermayer.cc> | 2021-08-28 20:03:54 +0200 |
commit | 104a8399ae96f022a3662bd67668ad07e53e3093 (patch) | |
tree | 7b69d0cb9dfb7a2ef98c8c3ad916a97cbac4b70f | |
parent | 909faca929cf30dcd439fa33479177e76fb5121d (diff) |
avcodec/mjpegbdec: Skip SOS on AVDISCARD_ALL as does mjpeg
Fixes: NULL pointer dereference
Fixes: 36342/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MJPEGB_fuzzer-4579188072906752
Fixes: 36344/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MJPEGB_fuzzer-5049579300061184
Fixes: 36345/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MJPEGB_fuzzer-5301149845553152
Fixes: 36374/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MJPEGB_fuzzer-6056312352931840
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
-rw-r--r-- | libavcodec/mjpegbdec.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/libavcodec/mjpegbdec.c b/libavcodec/mjpegbdec.c index 87eebb8771..218be41192 100644 --- a/libavcodec/mjpegbdec.c +++ b/libavcodec/mjpegbdec.c @@ -119,9 +119,13 @@ read_header: 8 * FFMIN(field_size, buf_end - buf_ptr - sos_offs)); s->mjpb_skiptosod = (sod_offs - sos_offs - show_bits(&s->gb, 16)); s->start_code = SOS; - ret = ff_mjpeg_decode_sos(s, NULL, 0, NULL); - if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) - return ret; + if (avctx->skip_frame == AVDISCARD_ALL) { + skip_bits(&s->gb, get_bits_left(&s->gb)); + } else { + ret = ff_mjpeg_decode_sos(s, NULL, 0, NULL); + if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) + return ret; + } } if (s->interlaced) { |