tiffdec: Prevent illegal memory access caused by recycled pointers.

Message ID 20120314210242.6D8D55E088@aruru.libav.org
State New
Headers show

Commit Message

Janne Grunau March 14, 2012, 9:02 p.m.
Module: libav
Branch: release/0.8
Commit: 2744fdbd9e1ee6a10f7627147be6556d04c1a88a

Author:    Alex Converse <alex.converse@gmail.com>
Committer: Reinhard Tartler <siretart@tauware.de>
Date:      Tue Mar  6 17:00:29 2012 -0800

tiffdec: Prevent illegal memory access caused by recycled pointers.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
(cherry picked from commit fd0be63049ed46660993d0550a4f0847a0b942ea)

Signed-off-by: Reinhard Tartler <siretart@tauware.de>

---

 libavcodec/tiff.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

Patch

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index d807149..a0db1f1 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -535,6 +535,8 @@  static int decode_frame(AVCodecContext *avctx,
         av_log(avctx, AV_LOG_ERROR, "The answer to life, universe and everything is not correct!\n");
         return -1;
     }
+    // Reset these pointers so we can tell if they were set this frame
+    s->stripsizes = s->stripdata = NULL;
     /* parse image file directory */
     off = tget_long(&buf, le);
     if (off >= UINT_MAX - 14 || end_buf - orig_buf < off + 14) {