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Date: Fri, 2 Apr 2010 10:46:24 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Oleg Nesterov <oleg@redhat.com>
cc: Andrew Morton <akpm@linux-foundation.org>, Alan Cox <alan@linux.intel.com>,
       Greg KH <greg@kroah.com>, Catalin Marinas <catalin.marinas@arm.com>,
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       "Eric W. Biederman" <ebiederm@xmission.com>,
       Sukadev Bhattiprolu <sukadev@us.ibm.com>, stable@kernel.org
Subject: Re: [PATCH 1/1] tty: release_one_tty() forgets to put pids
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On Fri, 2 Apr 2010, Oleg Nesterov wrote:
>
> release_one_tty(tty) can be called when tty still has a reference
> to pgrp/session. In this case we leak the pid.

Hmm. Maybe we should have cleared this in tty_release() already. We 
already do some of the session clearing there (but we clear the session in 
the _tasks_ associated with the tty, not the tty session pointer).

But:

> The patch needs the ack from someone who understand tty magic.

I think the patch is simpler than worrying about the much more complex 
release logic. So I think I actually prefer this patch over something that 
tries to be clever in tty_release.

We might even push it into "free_tty_struct()", although I think that the 
only non-release_one_tty() callers of that are the ones that allocated the 
tty but due to some failure never connected it to anything. So on the 
whole I think you picked the right spot.

So I'll ACK it. But maybe Alan sees some problem/issue I didn't see.

			Linus