[FFmpeg-cvslog] ffv1: fix integer overflow in quant table initialization

[Michael Niedermayer]

ffmpeg | branch: release/0.11 | Michael Niedermayer <michaelni at gmx.at> | Sat Jun  2 02:37:36 2012 +0200| [dc72a59fe53b0003c254b3f17bf0385eeca7e43d] | committer: Michael Niedermayer

ffv1: fix integer overflow in quant table initialization

Fixes part of Ticket1372

Found-by: Piotr Bandurski <ami_stuff at o2.pl>
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
(cherry picked from commit 9ebe6e391071690dbee79a645c51b14bd55c2ff4)

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

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=dc72a59fe53b0003c254b3f17bf0385eeca7e43d
---

 libavcodec/ffv1.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
index 79409e2..21f1761 100644
--- a/libavcodec/ffv1.c
+++ b/libavcodec/ffv1.c
@@ -1651,9 +1651,9 @@ static int read_quant_table(RangeCoder *c, int16_t *quant_table, int scale){
     memset(state, 128, sizeof(state));
 
     for(v=0; i<128 ; v++){
-        int len= get_symbol(c, state, 0) + 1;
+        unsigned len= get_symbol(c, state, 0) + 1;
 
-        if(len + i > 128) return -1;
+        if(len > 128 - i) return -1;
 
         while(len--){
             quant_table[i] = scale*v;