In commit d9cdc9033181 ("ext4 crypto: enforce context consistency") we
declared that:
2) All files or directories in a directory must be protected using the
same key as their containing directory.
But in f2fs_cross_rename there is a vulnerability that allow to cross
rename unencrypted file into encrypted directory, it needs to be refused.
Signed-off-by: Chao Yu <yuch...@huawei.com>
---
fs/f2fs/namei.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 25c073f6c7d4..8de684b84cb9 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -855,6 +855,10 @@ static int f2fs_cross_rename(struct inode *old_dir, struct
dentry *old_dentry,
!fscrypt_has_encryption_key(new_dir)))
return -ENOKEY;
+ if (f2fs_encrypted_inode(old_dir) && !f2fs_encrypted_inode(new_inode) ||
+ f2fs_encrypted_inode(new_dir) &&
!f2fs_encrypted_inode(old_inode))
+ return -EPERM;
+
if ((f2fs_encrypted_inode(old_dir) || f2fs_encrypted_inode(new_dir)) &&
(old_dir != new_dir) &&
(!fscrypt_has_permitted_context(new_dir, old_inode) ||
--
2.8.2.295.g3f1c1d0
