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Date: Wed, 19 Oct 2016 11:33:27 -0700
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] mm: kmemleak: Ensure that the task stack is not freed
 during scanning
Message-Id: <20161019113327.3e796893d89333f6ebe65d79@linux-foundation.org>
In-Reply-To: <1476266223-14325-1-git-send-email-catalin.marinas@arm.com>
References: <1476266223-14325-1-git-send-email-catalin.marinas@arm.com>
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To: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andy Lutomirski <luto@kernel.org>, CAI Qian <caiqian@redhat.com>

On Wed, 12 Oct 2016 10:57:03 +0100 Catalin Marinas <catalin.marinas@arm.com> wrote:

> Commit 68f24b08ee89 ("sched/core: Free the stack early if
> CONFIG_THREAD_INFO_IN_TASK") may cause the task->stack to be freed
> during kmemleak_scan() execution, leading to either a NULL pointer
> fault (if task->stack is NULL) or kmemleak accessing already freed
> memory. This patch uses the new try_get_task_stack() API to ensure that
> the task stack is not freed during kmemleak stack scanning.
> 
> Fixes: 68f24b08ee89 ("sched/core: Free the stack early if CONFIG_THREAD_INFO_IN_TASK")
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: CAI Qian <caiqian@redhat.com>
> Reported-by: CAI Qian <caiqian@redhat.com>
> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

I'll add

Cc: <stable@vger.kernel.org>    [4.8.x]

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