f2fs crypto: check context consistent for rename2
For exchange rename, we should check context consistent of encryption
between new_dir and old_inode or old_dir and new_inode. Otherwise
inheritance of parent's encryption context will be broken.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: sync with ext4 approach]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 55d0d27..1cc24a0 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -756,6 +756,14 @@
int old_nlink = 0, new_nlink = 0;
int err = -ENOENT;
+ if ((f2fs_encrypted_inode(old_dir) || f2fs_encrypted_inode(new_dir)) &&
+ (old_dir != new_dir) &&
+ (!f2fs_is_child_context_consistent_with_parent(new_dir,
+ old_inode) ||
+ !f2fs_is_child_context_consistent_with_parent(old_dir,
+ new_inode)))
+ return -EPERM;
+
f2fs_balance_fs(sbi);
old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);