[FFmpeg-cvslog] brstm: make sure an ADPC chunk was read for adpcm_thp

[Andreas Cadhalpun]

ffmpeg | branch: release/2.8 | Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com> | Mon Jan  4 12:57:38 2016 +0100| [94b9e7caaea87a8caee587cf9123ec2e31aacf4b] | committer: Andreas Cadhalpun

brstm: make sure an ADPC chunk was read for adpcm_thp

This fixes NULL pointer dereferencing.

Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
(cherry picked from commit d7d37c479fa71639650751648275615e979beb33)
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=94b9e7caaea87a8caee587cf9123ec2e31aacf4b
---

 libavformat/brstm.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavformat/brstm.c b/libavformat/brstm.c
index 6eae9d9..7cb1341 100644
--- a/libavformat/brstm.c
+++ b/libavformat/brstm.c
@@ -389,6 +389,11 @@ static int read_packet(AVFormatContext *s, AVPacket *pkt)
         codec->codec_id == AV_CODEC_ID_ADPCM_THP_LE) {
         uint8_t *dst;
 
+        if (!b->adpc) {
+            av_log(s, AV_LOG_ERROR, "adpcm_thp requires ADPC chunk, but none was found.\n");
+            return AVERROR_INVALIDDATA;
+        }
+
         if (size > (INT_MAX - 32 - 4) ||
             (32 + 4 + size) > (INT_MAX / codec->channels) ||
             (32 + 4 + size) * codec->channels > INT_MAX - 8)