diff --git a/src/utils/common.c b/src/utils/common.c
index 39751d4..7dc4797 100644
--- a/src/utils/common.c
+++ b/src/utils/common.c
@@ -350,7 +350,7 @@
 	size_t i;
 
 	for (i = 0; i < len; i++) {
-		if (txt + 4 > end)
+		if (txt + 4 >= end)
 			break;
 
 		switch (data[i]) {
diff --git a/src/utils/utils_module_tests.c b/src/utils/utils_module_tests.c
index 75b169e..9a9ec40 100644
--- a/src/utils/utils_module_tests.c
+++ b/src/utils/utils_module_tests.c
@@ -67,6 +67,23 @@
 		}
 	}
 
+	buf[5] = 'A';
+	printf_encode(buf, 5, (const u8 *) "abcde", 5);
+	if (buf[5] != 'A') {
+		wpa_printf(MSG_ERROR, "Error in bounds checking#1");
+		errors++;
+	}
+
+	for (i = 5; i < 10; i++) {
+		buf[i] = 'A';
+		printf_encode(buf, i, (const u8 *) "\xdd\xdd\xdd\xdd\xdd", 5);
+		if (buf[i] != 'A') {
+			wpa_printf(MSG_ERROR, "Error in bounds checking#2(%d)",
+				   i);
+			errors++;
+		}
+	}
+
 	if (errors) {
 		wpa_printf(MSG_ERROR, "%d printf test(s) failed", errors);
 		return -1;