diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c
index 5fcfa96463ebb820cef33b83460fc8d1a9bea8b2..85521d6b023707c39a7809e441449b0d72ef3703 100644
--- a/fs/udf/unicode.c
+++ b/fs/udf/unicode.c
@@ -247,7 +247,7 @@ static int udf_name_from_CS0(struct super_block *sb,
 	}
 
 	if (translate) {
-		if (str_o_len <= 2 && str_o[0] == '.' &&
+		if (str_o_len > 0 && str_o_len <= 2 && str_o[0] == '.' &&
 		    (str_o_len == 1 || str_o[1] == '.'))
 			needsCRC = 1;
 		if (needsCRC) {