ext4: require encryption feature for EXT4_IOC_SET_ENCRYPTION_POLICY

commit 9a200d075e5d05be1fcad4547a0f8aee4e2f9a04 upstream.

...otherwise an user can enable encryption for certain files even
when the filesystem is unable to support it.
Such a case would be a filesystem created by mkfs.ext4's default
settings, 1KiB block size. Ext4 supports encyption only when block size
is equal to PAGE_SIZE.
But this constraint is only checked when the encryption feature flag
is set.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Richard Weinberger 2016-09-30 01:49:55 -04:00 committed by Greg Kroah-Hartman
parent fee1f42b96
commit e2968fb8e7

View file

@ -622,6 +622,9 @@ resizefs_out:
struct ext4_encryption_policy policy;
int err = 0;
if (!ext4_has_feature_encrypt(sb))
return -EOPNOTSUPP;
if (copy_from_user(&policy,
(struct ext4_encryption_policy __user *)arg,
sizeof(policy))) {