[PATCH v2 35/39] ecryptfs: do not mount on top of idmapped mounts

Prevent ecryptfs from being mounted on top of idmapped mounts until we have ported it to handle this case and added proper testing for it. Cc: Christoph Hellwig <hch(a)lst.de&gt; Cc: David Howells <dhowells(a)redhat.com&gt; Cc: Al Viro <viro(a)zeniv.linux.org.uk&gt; Cc: linux-fsdevel(a)vger.kernel.org Signed-off-by: Christian Brauner <christian.brauner(a)ubuntu.com&gt; --- /* v2 */ patch introduced --- fs/ecryptfs/main.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index e63259fdef28..c739f42157db 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -531,6 +531,12 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags goto out_free; } + if (mnt_idmapped(path.mnt)) { + rc = -EINVAL; + printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n"); + goto out_free; + } + if (check_ruid && !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) { rc = -EPERM; printk(KERN_ERR "Mount of device (uid: %d) not owned by " -- 2.29.2