tick/broadcast: Prevent NULL pointer dereference
authorThomas Gleixner <tglx@linutronix.de>
Thu, 15 Dec 2016 11:10:37 +0000 (12:10 +0100)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 15 Dec 2016 11:25:13 +0000 (12:25 +0100)
commitc1a9eeb938b5433947e5ea22f89baff3182e7075
treeb6ebcc09e7d73f78a5f57b1e0ad796655f23586f
parentf082f02c4731900a5065de69eb0d8cb5aab66196
tick/broadcast: Prevent NULL pointer dereference

When a disfunctional timer, e.g. dummy timer, is installed, the tick core
tries to setup the broadcast timer.

If no broadcast device is installed, the kernel crashes with a NULL pointer
dereference in tick_broadcast_setup_oneshot() because the function has no
sanity check.

Reported-by: Mason <slash.tmp@free.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Richard Cochran <rcochran@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Cc: Sebastian Frias <sf84@laposte.net>
Cc: Thibaud Cornic <thibaud_cornic@sigmadesigns.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Link: http://lkml.kernel.org/r/1147ef90-7877-e4d2-bb2b-5c4fa8d3144b@free.fr
kernel/time/tick-broadcast.c