[FFmpeg-cvslog] avcodec/jpeg2000dec: Check nonzerobits more completely

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Fri Jun 16 19:57:08 2017 +0200| [dfb61ea2630029b7aec7911aade769bf1a914eea] | committer: Michael Niedermayer

avcodec/jpeg2000dec: Check nonzerobits more completely

Fixes: runtime error: shift exponent 36 is too large for 32-bit type 'int'
Fixes: 2239/clusterfuzz-testcase-minimized-5639766592716800

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=dfb61ea2630029b7aec7911aade769bf1a914eea
---

 libavcodec/jpeg2000dec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index 09b72933f2..c3d2747675 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -960,9 +960,9 @@ static int jpeg2000_decode_packet(Jpeg2000DecoderContext *s, Jpeg2000Tile *tile,
             if (!cblk->npasses) {
                 int v = expn[bandno] + numgbits - 1 -
                         tag_tree_decode(s, prec->zerobits + cblkno, 100);
-                if (v < 0) {
+                if (v < 0 || v > 30) {
                     av_log(s->avctx, AV_LOG_ERROR,
-                           "nonzerobits %d invalid\n", v);
+                           "nonzerobits %d invalid or unsupported\n", v);
                     return AVERROR_INVALIDDATA;
                 }
                 cblk->nonzerobits = v;