sysctl: Allow creating permanently empty directories that serve as mountpoints.
authorEric W. Biederman <ebiederm@xmission.com>
Sun, 10 May 2015 03:09:14 +0000 (22:09 -0500)
committerEric W. Biederman <ebiederm@xmission.com>
Wed, 1 Jul 2015 15:36:39 +0000 (10:36 -0500)
commitf9bd6733d3f11e24f3949becf277507d422ee1eb
tree79d33823e26cb5be0af93bae37b2abca3fdaa5dc
parentfbabfd0f4ee2e8847bf56edf481249ad1bb8c44d
sysctl: Allow creating permanently empty directories that serve as mountpoints.

Add a magic sysctl table sysctl_mount_point that when used to
create a directory forces that directory to be permanently empty.

Update the code to use make_empty_dir_inode when accessing permanently
empty directories.

Update the code to not allow adding to permanently empty directories.

Update /proc/sys/fs/binfmt_misc to be a permanently empty directory.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
fs/proc/proc_sysctl.c
include/linux/sysctl.h
kernel/sysctl.c