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From: Christian Borntraeger <borntraeger@de.ibm.com>
Organization: IBM
To: Evgeniy Polyakov <zbr@ioremap.net>
Subject: Re: [PATCH] connector: Fix sid connector (was: Badness at kernel/softirq.c:143...)
Date: Tue, 29 Sep 2009 16:15:38 +0200
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Cc: Oleg Nesterov <oleg@redhat.com>, Evgeny Polyakov <johnpol@2ka.mipt.ru>,
       Scott James Remnant <scott@ubuntu.com>,
       Linux Kernel <linux-kernel@vger.kernel.org>,
       Matt Helsley <matthltc@us.ibm.com>,
       "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org
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Am Dienstag 29 September 2009 16:07:18 schrieb Evgeniy Polyakov:
> Your patch breaks assumption that task_session(current->group_leader) is
> not equal to new session id, but to check task_session() we need either
> rcu or task lock. Also setsid() return value is not zero or negative
> error, but new session ID or negative error,

Right.

> so I believe attached patch is a proper fix, although it looks rather ugly.
> 
> Also proc_sid_connector() uses GFP_KERNEL allocation which is way too
> wrong to use under any locks.
> 
> Something like this (not tested :)

Patch compiles and seems to work.

Christian