x86/irq: Validate that irq descriptor is still active

commit 36f34c8c63da3e272fd66f91089228c22d2b6e8b upstream.

In fixup_irqs() we unconditionally dereference the irq chip of an irq
descriptor. The descriptor might still be valid, but already cleaned up,
i.e. the chip removed. Add a check for this condition.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joe Lawrence <joe.lawrence@stratus.com>
Cc: Jeremiah Mahler <jmmahler@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: andy.shevchenko@gmail.com
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20151231160106.236423282@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Thomas Gleixner 2015-12-31 16:30:45 +00:00 committed by Greg Kroah-Hartman
parent e4d1544b1e
commit 053c8ecc22

View File

@ -470,6 +470,15 @@ void fixup_irqs(void)
}
chip = irq_data_get_irq_chip(data);
/*
* The interrupt descriptor might have been cleaned up
* already, but it is not yet removed from the radix tree
*/
if (!chip) {
raw_spin_unlock(&desc->lock);
continue;
}
if (!irqd_can_move_in_process_context(data) && chip->irq_mask)
chip->irq_mask(data);