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Date:   Mon, 9 Sep 2019 17:13:43 +0200
From:   Frederic Weisbecker <frederic@kernel.org>
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Ingo Molnar <mingo@kernel.org>,
        Kees Cook <keescook@chromium.org>
Subject: Re: [patch V2 2/6] posix-cpu-timers: Fix permission check regression
Message-ID: <20190909151342.GA2319@lerouge>
References: <20190905120339.561100423@linutronix.de>
 <20190905120539.797994508@linutronix.de>
 <20190905173148.GE18251@lenoir>
 <alpine.DEB.2.21.1909052054200.1902@nanos.tec.linutronix.de>
 <alpine.DEB.2.21.1909052314110.1902@nanos.tec.linutronix.de>
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On Thu, Sep 05, 2019 at 11:15:08PM +0200, Thomas Gleixner wrote:
> +	if (gettime) {
> +		/*
> +		 * For clock_gettime(PROCESS) the task does not need to be
> +		 * the actual group leader. tsk->sighand gives
> +		 * access to the group's clock.
> +		 *
> +		 * Timers need the group leader because they take a
> +		 * reference on it and store the task pointer until the
> +		 * timer is destroyed.

Well, that would work with a non group leader as well but anyway that wouldn't
be pretty.

Reviewed-by: Frederic Weisbecker <frederic@kernel.org>