gpio: Restrict usage of GPIO chip irq members before initialization

commit 5467801f1fcbdc46bc7298a84dbf3ca1ff2a7320 upstream.

GPIO chip irq members are exposed before they could be completely
initialized and this leads to race conditions.

One such issue was observed for the gc->irq.domain variable which
was accessed through the I2C interface in gpiochip_to_irq() before
it could be initialized by gpiochip_add_irqchip(). This resulted in
Kernel NULL pointer dereference.

Following are the logs for reference :-

kernel: Call Trace:
kernel:  gpiod_to_irq+0x53/0x70
kernel:  acpi_dev_gpio_irq_get_by+0x113/0x1f0
kernel:  i2c_acpi_get_irq+0xc0/0xd0
kernel:  i2c_device_probe+0x28a/0x2a0
kernel:  really_probe+0xf2/0x460
kernel: RIP: 0010:gpiochip_to_irq+0x47/0xc0

To avoid such scenarios, restrict usage of GPIO chip irq members before
they are completely initialized.

Signed-off-by: Shreeya Patel <shreeya.patel@collabora.com>
Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Shreeya Patel
2022-03-21 19:02:41 +05:30
committed by Greg Kroah-Hartman
parent 9ca11bd822
commit 0912cf021f
2 changed files with 28 additions and 0 deletions

View File

@@ -224,6 +224,15 @@ struct gpio_irq_chip {
unsigned long *valid_mask,
unsigned int ngpios);
/**
* @initialized:
*
* Flag to track GPIO chip irq member's initialization.
* This flag will make sure GPIO chip irq members are not used
* before they are initialized.
*/
bool initialized;
/**
* @valid_mask:
*