[PATCH 5.19 051/207] gpio: mockup: fix NULL pointer dereference when removing debugfs

Greg Kroah-Hartman
2022-09-26T11:57:00Z

From: Bartosz Golaszewski <brgl@bgdev.pl>

commit b7df41a6f79dfb18ba2203f8c5f0e9c0b9b57f68 upstream.

We now remove the device's debugfs entries when unbinding the driver.
This now causes a NULL-pointer dereference on module exit because the
platform devices are unregistered *after* the global debugfs directory
has been recursively removed. Fix it by unregistering the devices first.

Fixes: 303e6da99429 ("gpio: mockup: remove gpio debugfs when remove device")
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpio/gpio-mockup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -597,9 +597,9 @@ static int __init gpio_mockup_init(void)

static void __exit gpio_mockup_exit(void)
{
+ gpio_mockup_unregister_pdevs();
debugfs_remove_recursive(gpio_mockup_dbg_dir);
platform_driver_unregister(&gpio_mockup_driver);
- gpio_mockup_unregister_pdevs();
}

module_init(gpio_mockup_init);