Fix util_is_printable_string

The method used did not account for multi-part strings.

Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>

util.c

@@ -72,7 +72,7 @@ char *join_path(const char *path, const char *name)
 int util_is_printable_string(const void *data, int len)
 {
 	const char *s = data;
-	const char *ss;
+	const char *ss, *se;
 
 	/* zero length is not */
 	if (len == 0)
@@ -82,14 +82,20 @@ int util_is_printable_string(const void *data, int len)
 	if (s[len - 1] != '\0')
 		return 0;
 
+	se = s + len;
+
+	while (s < se) {
 		ss = s;
-	while (*s && isprint(*s))
+		while (s < se && *s && isprint(*s))
 			s++;
 
 		/* not zero, or not done yet */
-	if (*s != '\0' || (s + 1 - ss) < len)
+		if (*s != '\0' || s == ss)
 			return 0;
 
+		s++;
+	}
+
 	return 1;
 }