[libav-stable] pngdec: Stop trying to decode once inflate returns Z_STREAM_END

Martin Storsjö git at libav.org
Sun Sep 29 19:07:52 CEST 2013


Module: libav
Branch: master
Commit: a81cad8f86d1feb7e4bfae29e43f3e994935a5c7

Author:    Martin Storsjö <martin at martin.st>
Committer: Martin Storsjö <martin at martin.st>
Date:      Sun Sep 29 00:12:04 2013 +0300

pngdec: Stop trying to decode once inflate returns Z_STREAM_END

If the input buffer contains more data after the deflate stream,
the loop previously left running infinitely, with inflate returning
Z_STREAM_END.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable at libav.org
Signed-off-by: Martin Storsjö <martin at martin.st>

---

 libavcodec/pngdec.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index ec44d56..8864e4a 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -378,6 +378,10 @@ static int png_decode_idat(PNGDecContext *s, int length)
             s->zstream.avail_out = s->crow_size;
             s->zstream.next_out  = s->crow_buf;
         }
+        if (ret == Z_STREAM_END && s->zstream.avail_in > 0) {
+            av_log(NULL, AV_LOG_WARNING, "%d undecompressed bytes left in buffer\n", s->zstream.avail_in);
+            return 0;
+        }
     }
     return 0;
 }



More information about the libav-stable mailing list