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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>, akpm@osdl.org,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Remove BKL from sysctl(2)
References: <20080122202727.GB1975@martell.zuzino.mipt.ru>
	<20080123105140.3406e25b@lxorguk.ukuu.org.uk>
From: Andi Kleen <andi@firstfloor.org>
Date: 23 Jan 2008 12:09:05 +0100
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Alan Cox <alan@lxorguk.ukuu.org.uk> writes:
> 
> There are cases that updating the corepath name and dumping a core at the
> same moment can result in the wrong thing being exec()'d or a file being
> opened which is a mix of the old and new name and could go anywhere.
> 
> I see two variants on your patch that work
> 
> #1	Replace the lock_kernel with a sysctl_update mutex and fix both
> paths
> #2	Add locking specifically to the corename path

Doesn't that apply to pretty much all proc_dostring users, not just
corename? 

Some of them might be already broken if their readers don't take BKL.
Also possibly some of the proc_dointvec for multiple numbers.

-Andi