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Date: Tue, 31 Jan 2017 12:45:07 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Dmitry Vyukov <dvyukov@google.com>
cc: Al Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: timerfd: use-after-free in timerfd_remove_cancel
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On Tue, 31 Jan 2017, Thomas Gleixner wrote:

> On Mon, 30 Jan 2017, Dmitry Vyukov wrote:
> > 
> > Seems that ctx->might_cancel is racy.
> 
> Yes, it is. Fix below.

And the fix is racy as well. Darn, we really need to lock the context to
avoid that mess.