[FFmpeg-cvslog] asfdec: fix assert failure on invalid files

[Uoti Urpala]

ffmpeg | branch: master | Uoti Urpala <uoti.urpala.pp1.inet.fi> | Sun Apr 24 07:21:30 2011 +0300| [0bd433a916cd8d98fce47742fbf6d0f90ec941c4] | committer: Ronald S. Bultje

asfdec: fix assert failure on invalid files

Add an extra size validity check in asf_read_frame_header(). Without
this asf->packet_size_left may become negative, which triggers an
assertion failure later.

Signed-off-by: Ronald S. Bultje <rsbultje at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0bd433a916cd8d98fce47742fbf6d0f90ec941c4
---

 libavformat/asfdec.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/libavformat/asfdec.c b/libavformat/asfdec.c
index 637ceed..77c8449 100644
--- a/libavformat/asfdec.c
+++ b/libavformat/asfdec.c
@@ -864,6 +864,10 @@ static int asf_read_frame_header(AVFormatContext *s, AVIOContext *pb){
         }
         //printf("Fragsize %d\n", asf->packet_frag_size);
     } else {
+        if (rsize > asf->packet_size_left) {
+            av_log(s, AV_LOG_ERROR, "packet_replic_size is invalid\n");
+            return -1;
+        }
         asf->packet_frag_size = asf->packet_size_left - rsize;
         //printf("Using rest  %d %d %d\n", asf->packet_frag_size, asf->packet_size_left, rsize);
     }