[FFmpeg-cvslog] avcodec/jpeg2000dec: Replace the step_x/y assert by a check in the CPRL case as with the PCRL case

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Tue Apr 16 00:54:09 2019 +0200| [6381b6f6a9736f9bae92618c3d43c50b21810146] | committer: Michael Niedermayer

avcodec/jpeg2000dec: Replace the step_x/y assert by a check in the CPRL case as with the PCRL case

Fixes: assertion failure
Fixes: 14246/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_JPEG2000_fuzzer-5758393601490944

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

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6381b6f6a9736f9bae92618c3d43c50b21810146
---

 libavcodec/jpeg2000dec.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index 7749c980e5..9198cf87cb 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -1171,7 +1171,10 @@ static int jpeg2000_decode_packets_po_iteration(Jpeg2000DecoderContext *s, Jpeg2
                 step_x = FFMIN(step_x, rlevel->log2_prec_width  + reducedresno);
                 step_y = FFMIN(step_y, rlevel->log2_prec_height + reducedresno);
             }
-            av_assert0(step_x < 32 && step_y < 32);
+            if (step_x >= 31 || step_y >= 31){
+                avpriv_request_sample(s->avctx, "CPRL with large step");
+                return AVERROR_PATCHWELCOME;
+            }
             step_x = 1<<step_x;
             step_y = 1<<step_y;