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Date: Sat, 22 Mar 2003 12:44:47 -0800
From: Andrew Morton <akpm@digeo.com>
To: Manfred Spraul <manfred@colorfullife.com>
Cc: zwane@holomorphy.com, linux-kernel@vger.kernel.org, jochen@jochen.org
Subject: Re: BUG: Use after free in detach_pid
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Manfred Spraul <manfred@colorfullife.com> wrote:
>
> You mentioned that the last detach_pid() within __unhash_process oopsed. That means the reference count of the task structure was off by one, and the
> 	put_task_struct(pid->task)
> within 
> 	detach_pid(p,PIDTYPE_PGID);
> freed the task structure.
> 

Might be related to http://bugme.osdl.org/show_bug.cgi?id=482
in which someone did put_task_struct() on an already-freed task_struct.

And that was a uniprocessor without pgcl gunk.

It is not known whether preemption was enabled?

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