From 91510d5959ad9eac451685e3bfc8385b89c23908 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Fri, 16 Feb 2024 11:59:30 +0100 Subject: gpio: cdev: fix a NULL-pointer dereference with DEBUG enabled We are actually passing the gc pointer to chip_dbg() so we have to srcu_dereference() it. Fixes: 8574b5b47610 ("gpio: cdev: use correct pointer accessors with SRCU") Reported-by: Marek Szyprowski Closes: https://lore.kernel.org/lkml/179caa10-5f86-4707-8bb0-fe1b316326d6@samsung.com/ Signed-off-by: Bartosz Golaszewski Tested-by: Marek Szyprowski --- drivers/gpio/gpiolib-cdev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/gpio') diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index 85037fa4925e..f384fa278764 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -2795,8 +2795,8 @@ int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt) return ret; guard(srcu)(&gdev->srcu); - - if (!rcu_access_pointer(gdev->chip)) + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) return -ENODEV; chip_dbg(gc, "added GPIO chardev (%d:%d)\n", MAJOR(devt), gdev->id); -- cgit v1.2.3