tree 27a8565988791e2971d631e19c7a9a0057386668
parent 4041bcdc7bef06a2fb29c57394c713a74bd13b08
author Al Viro <viro@zeniv.linux.org.uk> 1326252288 -0500
committer Al Viro <viro@zeniv.linux.org.uk> 1326259198 -0500

autofs4: catatonic_mode vs. notify_daemon race

we need to hold ->wq_mutex while we are forming the packet to send,
lest we have autofs4_catatonic_mode() setting wq->name.name to NULL
just as autofs4_notify_daemon() decides to memcpy() from it...

We do have check for catatonic mode immediately after that (under
->wq_mutex, as it ought to be) and packet won't be actually sent,
but it'll be too late for us if we oops on that memcpy() from NULL...

Fix is obvious - just extend the area covered by ->wq_mutex over
that switch and check whether it's catatonic *before* doing anything
else.

Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>