Re: [Patch net] af_unix: move unix_mknod() out of bindlock

From: Cong Wang <redacted>
Date: Mon, 23 Jan 2017 11:17:35 -0800

Dmitry reported a deadlock scenario:

unix_bind() path:
u->bindlock ==> sb_writer

do_splice() path:
sb_writer ==> pipe->mutex ==> u->bindlock

In the unix_bind() code path, unix_mknod() does not have to
be done with u->bindlock held, since it is a pure fs operation,
so we can just move unix_mknod() out.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Rainer Weikusat <redacted>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Cong Wang <redacted>

Applied and queued up for -stable, thanks.