tweaks: some extra checks on lengths

src/util.cpp

@@ -241,6 +241,9 @@ int __acc_cdecl_qsort le64_compare_signed(const void *e1, const void *e2) {
 int find(const void *b, int blen, const void *what, int wlen) {
     if (b == NULL || blen <= 0 || what == NULL || wlen <= 0)
         return -1;
+    // Fast exit if the wanted string is longer than the buffer.
+    if (wlen > blen)
+        return -1;
 
     int i;
     const unsigned char *base = (const unsigned char *) b;