[FFmpeg-cvslog] jpeg2000: Check that we have enough components for MCT

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Mon Jul  1 10:01:15 2013 +0200| [cf04af2086be105ff86088357b83d672d38417d9] | committer: Luca Barbato

jpeg2000: Check that we have enough components for MCT

Avoid overread.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
Signed-off-by: Luca Barbato <lu_zero at gentoo.org>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=cf04af2086be105ff86088357b83d672d38417d9
---

 libavcodec/jpeg2000dec.c |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index d0608f9..2abba86 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -343,6 +343,13 @@ static int get_cod(Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *c,
     tmp.nlayers    = bytestream2_get_be16u(&s->g);
     tmp.mct        = bytestream2_get_byteu(&s->g); // multiple component transformation
 
+    if (tmp.mct && s->ncomponents < 3) {
+        av_log(s->avctx, AV_LOG_ERROR,
+               "MCT %d with too few components (%d)\n",
+               tmp.mct, s->ncomponents);
+        return AVERROR_INVALIDDATA;
+    }
+
     if ((ret = get_cox(s, &tmp)) < 0)
         return ret;