Added comment, added null pointer checking.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
---
  fs/ntfs3/inode.c | 8 +++++++-
  1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 8225d0b7c48c..51f9542de7b0 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -137,7 +137,13 @@ static struct inode *ntfs_read_mft(struct inode *inode,
      rsize = attr->non_res ? 0 : le32_to_cpu(attr->res.data_size);
      asize = le32_to_cpu(attr->size);

-    if (le16_to_cpu(attr->name_off) + attr->name_len > asize)
+    /*
+     * Really this check was done in 'ni_enum_attr_ex' -> ... 
'mi_enum_attr'.
+     * There not critical to check this case again
+     */
+    if (attr->name_len &&
+        sizeof(short) * attr->name_len + le16_to_cpu(attr->name_off) >
+            asize)
          goto out;

      if (attr->non_res) {
-- 
2.34.1