From: Michael Niedermayer <[email protected]>

Fixes CVE-2011-3937

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <[email protected]>
---
 libavcodec/h263dec.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index 4f0e456..c808be5 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -556,8 +556,7 @@ retry:
 #if HAVE_MMX
     if (s->codec_id == CODEC_ID_MPEG4 && s->xvid_build>=0 && avctx->idct_algo 
== FF_IDCT_AUTO && (av_get_cpu_flags() & AV_CPU_FLAG_MMX)) {
         avctx->idct_algo= FF_IDCT_XVIDMMX;
-        avctx->coded_width= 0; // force reinit
-//        ff_dsputil_init(&s->dsp, avctx);
+        ff_dct_common_init(s);
         s->picture_number=0;
     }
 #endif
@@ -571,6 +570,12 @@ retry:
         || s->height != avctx->coded_height) {
         /* H.263 could change picture size any time */
         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to 
avformat
+
+        if (HAVE_THREADS && (s->avctx->active_thread_type&FF_THREAD_FRAME)) {
+            av_log_missing_feature(s->avctx, "Width/height/bit depth/chroma 
idc changing with threads is", 0);
+            return -1;   // width / height changed during parallelized decoding
+        }
+
         s->parse_context.buffer=0;
         ff_MPV_common_end(s);
         s->parse_context= pc;
-- 
1.7.7.3

_______________________________________________
libav-devel mailing list
[email protected]
https://lists.libav.org/mailman/listinfo/libav-devel

Reply via email to