X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fsnowdec.c;h=0146a2a4c9ba0ddf79f51ba9c33d111816afbe65;hb=23f447294487958e0c7e8c01b9f9abedb1c7ba78;hp=a9bdb8da5ef0f4279f46fd319e114988d44e0c10;hpb=d268094f889479a8edee43d8c847da8838b8bf0f;p=ffmpeg

diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c
index a9bdb8da5ef..0146a2a4c9b 100644
--- a/libavcodec/snowdec.c
+++ b/libavcodec/snowdec.c
@@ -363,9 +363,10 @@ static int decode_header(SnowContext *s){
                 int htaps, i, sum=0;
                 Plane *p= &s->plane[plane_index];
                 p->diag_mc= get_rac(&s->c, s->header_state);
-                htaps= get_symbol(&s->c, s->header_state, 0)*2 + 2;
-                if((unsigned)htaps >= HTAPS_MAX || htaps==0)
+                htaps= get_symbol(&s->c, s->header_state, 0);
+                if((unsigned)htaps >= HTAPS_MAX/2 - 1)
                     return AVERROR_INVALIDDATA;
+                htaps = htaps*2 + 2;
                 p->htaps= htaps;
                 for(i= htaps/2; i; i--){
                     p->hcoeff[i]= get_symbol(&s->c, s->header_state, 0) * (1-2*(i&1));