fs/ntfs3: Correct hard links updating when dealing with DOS names

[ Upstream commit 1918c10e137eae266b8eb0ab1cc14421dcb0e3e2 ]

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/ntfs3/record.c b/fs/ntfs3/record.c
index 938fc286963f298288e49a1d8dc4cf62572a805a..ac43e4a6d57d1d0ec82f2a657805fa48e1a257e4 100644 (file)
--- a/fs/ntfs3/record.c
+++ b/fs/ntfs3/record.c
@@ -509,8 +509,20 @@ bool mi_remove_attr(struct ntfs_inode *ni, struct mft_inode *mi,
                return false;
 
        if (ni && is_attr_indexed(attr)) {
-               le16_add_cpu(&ni->mi.mrec->hard_links, -1);
-               ni->mi.dirty = true;
+               u16 links = le16_to_cpu(ni->mi.mrec->hard_links);
+               struct ATTR_FILE_NAME *fname =
+                       attr->type != ATTR_NAME ?
+                               NULL :
+                               resident_data_ex(attr,
+                                                SIZEOF_ATTRIBUTE_FILENAME);
+               if (fname && fname->type == FILE_NAME_DOS) {
+                       /* Do not decrease links count deleting DOS name. */
+               } else if (!links) {
+                       /* minor error. Not critical. */
+               } else {
+                       ni->mi.mrec->hard_links = cpu_to_le16(links - 1);
+                       ni->mi.dirty = true;
+               }
        }
 
        used -= asize;