[PATCH 5/8] ext4 crypto: enforce crypto policy restrictions on cross-renames

Theodore Ts'o
2015-05-28T23:48:28Z

Thanks to Chao Yu <chao2.yu@samsung.com> for pointing out the need for
this check.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
fs/ext4/namei.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 1e7d65d..401b099 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -3647,6 +3647,15 @@ static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
u8 new_file_type;
int retval;

+ if ((ext4_encrypted_inode(old_dir) ||
+ ext4_encrypted_inode(new_dir)) &&
+ (old_dir != new_dir) &&
+ (!ext4_is_child_context_consistent_with_parent(new_dir,
+ old.inode) ||
+ !ext4_is_child_context_consistent_with_parent(old_dir,
+ new.inode)))
+ return -EPERM;
+
dquot_initialize(old.dir);
dquot_initialize(new.dir);

--
2.3.0