dquot: For now explicitly don't support filesystems outside of init_user_ns

Mostly supporting filesystems outside of init_user_ns is
s/&init_usre_ns/dquot->dq_sb->s_user_ns/.  An actual need for
supporting quotas on filesystems outside of s_user_ns is quite a ways
away and to be done responsibily needs an audit on what can happen
with hostile quota files.  Until that audit is complete don't attempt
to support quota files on filesystems outside of s_user_ns.

Cc: Jan Kara <jack@suse.cz>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2016-07-05 10:41:57 -05:00
parent cfd4c70a18
commit 5c0048280b

View file

@ -2271,6 +2271,11 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
error = -EINVAL;
goto out_fmt;
}
/* Filesystems outside of init_user_ns not yet supported */
if (sb->s_user_ns != &init_user_ns) {
error = -EINVAL;
goto out_fmt;
}
/* Usage always has to be set... */
if (!(flags & DQUOT_USAGE_ENABLED)) {
error = -EINVAL;