diff --git a/lib/test-string_helpers.c b/lib/test-string_helpers.c
index 41d3447bc3b4..9a68849a5d55 100644
--- a/lib/test-string_helpers.c
+++ b/lib/test-string_helpers.c
@@ -587,7 +587,7 @@ static int __init test_string_helpers_init(void)
 	for (i = 0; i < UNESCAPE_ALL_MASK + 1; i++)
 		test_string_unescape("unescape", i, false);
 	test_string_unescape("unescape inplace",
-			     get_random_u32_below(UNESCAPE_ANY + 1), true);
+			     get_random_u32_below(UNESCAPE_ALL_MASK + 1), true);
 
 	/* Without dictionary */
 	for (i = 0; i < ESCAPE_ALL_MASK + 1; i++)