diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2016-12-15 12:10:37 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-12 11:39:45 +0100 |
| commit | cf365b117388a50902d56988e69dd6f70b7662fc (patch) | |
| tree | b9e8681010b1451d89deb7b85ae31fce3b463278 /kernel | |
| parent | 34db201f0de7138d3646946f5d33e178c93efca6 (diff) | |
tick/broadcast: Prevent NULL pointer dereference
commit c1a9eeb938b5433947e5ea22f89baff3182e7075 upstream.
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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/tick-broadcast.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index f6aae7977824..d2a20e83ebae 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -871,6 +871,9 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { int cpu = smp_processor_id(); + if (!bc) + return; + /* Set it up only once ! */ if (bc->event_handler != tick_handle_oneshot_broadcast) { int was_periodic = clockevent_state_periodic(bc); |