tree 48072d7daf0eaa2e244d6ecf08771c9e72fa62e1
parent 3f5c15d8a7d86fb642fe07df58c2065190f3e531
author Ian Kent <raven@themaw.net> 1534913921 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1534960369 -0700

autofs: fix directory and symlink access

Depending on how it is configured the autofs user space daemon can leave
in use mounts mounted at exit and re-connect to them at start up.  But for
this to work best the state of the autofs file system needs to be left
intact over the restart.

Also, at system shutdown, mounts in an autofs file system might be
umounted exposing a mount point trigger for which subsequent access can
lead to a hang.  So recent versions of automount(8) now does its best to
set autofs file system mounts catatonic at shutdown.

When autofs file system mounts are catatonic it's currently possible to
create and remove directories and symlinks which can be a problem at
restart, as described above.

So return EACCES in the directory, symlink and unlink methods if the
autofs file system is catatonic.

Link: http://lkml.kernel.org/r/152902119090.4144.9561910674530214291.stgit@pluto.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>