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Date: Mon, 6 Mar 2017 13:47:24 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        syzkaller <syzkaller@googlegroups.com>
Subject: Re: perf: use-after-free in perf_release
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On Mon, Mar 06, 2017 at 01:27:41PM +0100, Dmitry Vyukov wrote:

> I think you will also need the attached patch. It seems that it was
> found due to it. Going to send it out soon.

Yuck, that's nasty. Although I don't see an alternative there.

You might also want to do the bitops, they suffer the same problem.