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Date:   Mon, 15 Mar 2021 14:19:12 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     Cyrill Gorcunov <gorcunov@gmail.com>
Cc:     Alexey Dobriyan <adobriyan@gmail.com>, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, security@kernel.org
Subject: Re: [PATCH] prctl: fix PR_SET_MM_AUXV kernel stack leak
Message-ID: <20210315131911.GB13620@redhat.com>
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 <20210315120803.GA13620@redhat.com>
 <YE9ZGl9jlnDz1OBP@grain>
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On 03/15, Cyrill Gorcunov wrote:
>
> On Mon, Mar 15, 2021 at 01:08:03PM +0100, Oleg Nesterov wrote:
>
> >
> > And why task_lock(current) ? What does it try to protect?
>
> As far as I remember this was related to reading from procfs
> at time the patch was written for first time. Looks like this
> not relevant anymore and could be dropped.

I think this was never relevant, ->alloc_lock is per-thread, not per mm.

Oleg.