6.4-stable review patch. If anyone has any objections, please let me know.
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From: Bartosz Golaszewski bartosz.golaszewski@linaro.org
[ Upstream commit ab4109f91b328ff5cb5e1279f64d443241add2d1 ]
If a GPIO simulator device is unbound with interrupts still requested, we will hit a use-after-free issue in __irq_domain_deactivate_irq(). The owner of the irq domain must dispose of all mappings before destroying the domain object.
Fixes: cb8c474e79be ("gpio: sim: new testing module") Signed-off-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpio/gpio-sim.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/drivers/gpio/gpio-sim.c b/drivers/gpio/gpio-sim.c index f1f6f1c329877..8fb11a5395eb8 100644 --- a/drivers/gpio/gpio-sim.c +++ b/drivers/gpio/gpio-sim.c @@ -291,6 +291,15 @@ static void gpio_sim_mutex_destroy(void *data) mutex_destroy(lock); }
+static void gpio_sim_dispose_mappings(void *data) +{ + struct gpio_sim_chip *chip = data; + unsigned int i; + + for (i = 0; i < chip->gc.ngpio; i++) + irq_dispose_mapping(irq_find_mapping(chip->irq_sim, i)); +} + static void gpio_sim_sysfs_remove(void *data) { struct gpio_sim_chip *chip = data; @@ -406,6 +415,10 @@ static int gpio_sim_add_bank(struct fwnode_handle *swnode, struct device *dev) if (IS_ERR(chip->irq_sim)) return PTR_ERR(chip->irq_sim);
+ ret = devm_add_action_or_reset(dev, gpio_sim_dispose_mappings, chip); + if (ret) + return ret; + mutex_init(&chip->lock); ret = devm_add_action_or_reset(dev, gpio_sim_mutex_destroy, &chip->lock);