[FFmpeg-cvslog] avcodec/xface: Add asserts to limit nb_words from becoming too large

[Michael Niedermayer]

ffmpeg | branch: release/2.5 | Michael Niedermayer <michaelni at gmx.at> | Tue Dec 16 18:09:16 2014 +0100| [71b1abe6385601a7ef2a797c8e659f388a247dc3] | committer: Michael Niedermayer

avcodec/xface: Add asserts to limit nb_words from becoming too large

Approved-by: Stefano Sabatini <stefasab at gmail.com>
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
(cherry picked from commit 211200e0c0efa48b2815ce93fda10dab43526d1b)

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=71b1abe6385601a7ef2a797c8e659f388a247dc3
---

 libavcodec/xface.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavcodec/xface.c b/libavcodec/xface.c
index 0ebf2f2..8c0cbfd 100644
--- a/libavcodec/xface.c
+++ b/libavcodec/xface.c
@@ -24,6 +24,8 @@
  * X-Face common data and utilities definition.
  */
 
+#include "libavutil/avassert.h"
+
 #include "xface.h"
 
 void ff_big_add(BigInt *b, uint8_t a)
@@ -43,6 +45,7 @@ void ff_big_add(BigInt *b, uint8_t a)
         c >>= XFACE_BITSPERWORD;
     }
     if (i == b->nb_words && c) {
+        av_assert0(b->nb_words < XFACE_MAX_WORDS);
         b->nb_words++;
         *w = c & XFACE_WORDMASK;
     }
@@ -98,6 +101,7 @@ void ff_big_mul(BigInt *b, uint8_t a)
         return;
     if (a == 0) {
         /* treat this as a == WORDCARRY and just shift everything left a WORD */
+        av_assert0(b->nb_words < XFACE_MAX_WORDS);
         i = b->nb_words++;
         w = b->words + i;
         while (i--) {
@@ -116,6 +120,7 @@ void ff_big_mul(BigInt *b, uint8_t a)
         c >>= XFACE_BITSPERWORD;
     }
     if (c) {
+        av_assert0(b->nb_words < XFACE_MAX_WORDS);
         b->nb_words++;
         *w = c & XFACE_WORDMASK;
     }