[PATCH 10/11] irqchip/gic-v3-its: Lock VLPI map array before translating it

Marc Zyngier
2019-11-05T16:32:06Z

Obtaining the mapping information for a VLPI should always be
done with the vlpi_lock for this device held. Otherwise, we
expose ourselves to races against a concurrent unmap.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
drivers/irqchip/irq-gic-v3-its.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index dbb994f52e42..58ce231d5ade 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1489,12 +1489,14 @@ static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info)
static int its_vlpi_get(struct irq_data *d, struct its_cmd_info *info)
{
struct its_device *its_dev = irq_data_get_irq_chip_data(d);
- struct its_vlpi_map *map = get_vlpi_map(d);
+ struct its_vlpi_map *map;
int ret = 0;

mutex_lock(&its_dev->event_map.vlpi_lock);

- if (!its_dev->event_map.vm || !map->vm) {
+ map = get_vlpi_map(d);
+
+ if (!its_dev->event_map.vm || !map) {
ret = -EINVAL;
goto out;
}
--
2.20.1