tiff: Check that there is no aliasing in pixel format selection

Message ID 20150308181436.8E2B65DDF7@aruru.libav.org
State New
Headers show

Commit Message

Janne Grunau March 8, 2015, 6:14 p.m.
Module: libav
Branch: master
Commit: ae5e1f3d663a8c9a532d89e588cbc61f171c9186

Author:    Anton Khirnov <anton@khirnov.net>
Committer: Luca Barbato <lu_zero@gentoo.org>
Date:      Sat Mar  7 22:06:59 2015 +0100

tiff: Check that there is no aliasing in pixel format selection

Fixes possible issues with unexpected bpp/bppcount values.

CC: libav-stable@libav.org
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Bug-Id: CVE-2014-8544
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

---

 libavcodec/tiff.c |    8 ++++++++
 1 file changed, 8 insertions(+)

Patch

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index 08e8a87..b071c3b 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -252,6 +252,14 @@  static int init_image(TiffContext *s, AVFrame *frame)
 {
     int ret;
 
+    // make sure there is no aliasing in the following switch
+    if (s->bpp >= 100 || s->bppcount >= 10) {
+        av_log(s->avctx, AV_LOG_ERROR,
+               "Unsupported image parameters: bpp=%d, bppcount=%d\n",
+               s->bpp, s->bppcount);
+        return AVERROR_INVALIDDATA;
+    }
+
     switch (s->planar * 1000 + s->bpp * 10 + s->bppcount) {
     case 11:
         s->avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;