[FFmpeg-cvslog] avcodec/pgssubdec: Free subtitle on error

[Michael Niedermayer]

ffmpeg | branch: release/2.8 | Michael Niedermayer <michael at niedermayer.cc> | Sat Jan  4 21:58:28 2020 +0100| [9f9cedf29fd8d10aa5dc69031151f02e47e0a04a] | committer: Michael Niedermayer

avcodec/pgssubdec: Free subtitle on error

Fixes: Assertion failure
Fixes: 19753/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGSSUB_fuzzer-5688461843759104

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit b0a718923bb4a75b0c1cbf283fb17a319b840346)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=9f9cedf29fd8d10aa5dc69031151f02e47e0a04a
---

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

diff --git a/libavcodec/pgssubdec.c b/libavcodec/pgssubdec.c
index 136cd950ce..0877ac73e0 100644
--- a/libavcodec/pgssubdec.c
+++ b/libavcodec/pgssubdec.c
@@ -677,8 +677,11 @@ static int decode(AVCodecContext *avctx, void *data, int *data_size,
             ret = AVERROR_INVALIDDATA;
             break;
         }
-        if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
+        if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE)) {
+            avsubtitle_free(data);
+            *data_size = 0;
             return ret;
+        }
 
         buf += segment_length;
     }