[FFmpeg-cvslog] avcodec/wmaprodec: Fix integer overflow in sfb_offsets initialization

[Michael Niedermayer]

ffmpeg | branch: release/0.7 | Michael Niedermayer <michaelni at gmx.at> | Mon Nov 10 23:07:50 2014 +0100| [f78f7eca1a5ce67db6b1f8a159dc47cc57e8d43a] | committer: Michael Niedermayer

avcodec/wmaprodec: Fix integer overflow in sfb_offsets initialization

Fixes out of array read
Fixes: asan_heap-oob_2aec5b0_1828_classical_22_16_2_16000_v3c_0_exclusive_0_29.wma
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
(cherry picked from commit 5dcb99033df16eccc4dbbc4a099ad64457f9f090)

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f78f7eca1a5ce67db6b1f8a159dc47cc57e8d43a
---

 libavcodec/wmaprodec.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/wmaprodec.c b/libavcodec/wmaprodec.c
index 816d95f..67c62a4 100644
--- a/libavcodec/wmaprodec.c
+++ b/libavcodec/wmaprodec.c
@@ -404,6 +404,9 @@ static av_cold int decode_init(AVCodecContext *avctx)
             offset &= ~3;
             if (offset > s->sfb_offsets[i][band - 1])
                 s->sfb_offsets[i][band++] = offset;
+
+            if (offset >= subframe_len)
+                break;
         }
         s->sfb_offsets[i][band - 1] = subframe_len;
         s->num_sfb[i]               = band - 1;