fs/ntfs3: Fix possible deadlock in mi_read

[ Upstream commit 03b097099eef255fbf85ea6a786ae3c91b11f041 ]

Mutex lock with another subclass used in ni_lock_dir().

Reported-by: syzbot+bc7ca0ae4591cb2550f9@syzkaller.appspotmail.com
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
index a9549e73081fb91bfc379beddbb72a9bcbec5b88..7cad1bc2b314f5b2c6c65313a70f19ee00d03f93 100644 (file)
--- a/fs/ntfs3/namei.c
+++ b/fs/ntfs3/namei.c
@@ -79,7 +79,7 @@ static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *dentry,
                if (err < 0)
                        inode = ERR_PTR(err);
                else {
-                       ni_lock(ni);
+                       ni_lock_dir(ni);
                        inode = dir_search_u(dir, uni, NULL);
                        ni_unlock(ni);
                }