CVE-2017-14160: fix bounds check on very low sample rates.

lib/psy.c

@@ -602,8 +602,9 @@ static void bark_noise_hybridmp(int n,const long *b,
   for (i = 0, x = 0.f;; i++, x += 1.f) {
 
     lo = b[i] >> 16;
-    if( lo>=0 ) break;
     hi = b[i] & 0xffff;
+    if( lo>=0 ) break;
+    if( hi>=n ) break;
 
     tN = N[hi] + N[-lo];
     tX = X[hi] - X[-lo];