Add proper guarding to cases where declared floor/residue decode size

is *larger* than the current blocksize.  Handle according to spec.



git-svn-id: https://svn.xiph.org/trunk/Tremor@13156 0101bb08-14d6-0310-b084-bc0e0c8e3800

1 files changed, 6 insertions, 4 deletions

diff --git a/floor1.c b/floor1.c
index 80c6dd2..276ed8d 100644
--- a/floor1.c
+++ b/floor1.c
@@ -282,7 +282,7 @@ static const ogg_int32_t FLOOR_fromdB_LOOKUP[256]={
   XdB(0x69f80e9a), XdB(0x70dafda8), XdB(0x78307d76), XdB(0x7fffffff),
 };
   
-static void render_line(int x0,int x1,int y0,int y1,ogg_int32_t *d){
+static void render_line(int n, int x0,int x1,int y0,int y1,ogg_int32_t *d){
   int dy=y1-y0;
   int adx=x1-x0;
   int ady=abs(dy);
@@ -292,11 +292,13 @@ static void render_line(int x0,int x1,int y0,int y1,ogg_int32_t *d){
   int y=y0;
   int err=0;
 
+  if(n>x1)n=x1;
   ady-=abs(base*adx);
 
-  d[x]= MULT31_SHIFT15(d[x],FLOOR_fromdB_LOOKUP[y]);
+  if(x<n)
+    d[x]= MULT31_SHIFT15(d[x],FLOOR_fromdB_LOOKUP[y]);
 
-  while(++x<x1){
+  while(++x<n){
     err=err+ady;
     if(err>=adx){
       err-=adx;
@@ -418,7 +420,7 @@ static int floor1_inverse2(vorbis_block *vb,vorbis_look_floor *in,void *memo,
 	hy*=info->mult;
 	hx=info->postlist[current];
 	
-	render_line(lx,hx,ly,hy,out);
+	render_line(n,lx,hx,ly,hy,out);
 	
 	lx=hx;
 	ly=hy;