diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 99c4a868d73b..fc887f163fcc 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -77,7 +77,8 @@ static unsigned long dir_block_index(unsigned int level,
 	unsigned long bidx = 0;
 
 	for (i = 0; i < level; i++)
-		bidx += dir_buckets(i, dir_level) * bucket_blocks(i);
+		bidx += mul_u32_u32(dir_buckets(i, dir_level),
+				    bucket_blocks(i));
 	bidx += idx * bucket_blocks(level);
 	return bidx;
 }