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Date: Fri, 2 Apr 2010 17:29:22 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
       Catalin Marinas <catalin.marinas@arm.com>,
       Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
       linux-kernel@vger.kernel.org,
       "Eric W. Biederman" <ebiederm@xmission.com>,
       Sukadev Bhattiprolu <sukadev@us.ibm.com>
Subject: Re: [2.6.31 and later] "struct pid" leak.
Message-ID: <20100402152922.GA17727@redhat.com>
References: <201003272121.ADE39095.JLFHOOMtSVOFQF@I-love.SAKURA.ne.jp> <tnxbpe5ygfy.fsf@e102109-lin.cambridge.arm.com> <20100331151719.8a92b302.akpm@linux-foundation.org> <20100401165247.GB19551@redhat.com> <20100401172120.GA3111@us.ibm.com>
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Serge, Catalin, thanks a lot for the debugging output you sent
me privately ;)

On 04/01, Serge E. Hallyn wrote:
>
> Quoting Oleg Nesterov (oleg@redhat.com):
> >
> > Oh. It is hardly possibly to find the unbalanced get_pid() via grep.
>
> Looking through vt_ioctl.c,

Yes, my first reaction was "it must be tty" too ;)

I seem to understand what happens. If I am right, it is possible
to leak the pid even without X.

I'll try to check my theory and send the patch soon...

Oleg.