Commit a05a1404 authored by Vladimir Zapolskiy's avatar Vladimir Zapolskiy Committed by Linus Walleij
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gpio: don't free unallocated ida on gpiochip_add_data_with_key() error path 



The change corrects the error path in gpiochip_add_data_with_key()
by avoiding to call ida_simple_remove(), if ida_simple_get() returns
an error.

Note that ida_simple_remove()/ida_free() throws a BUG(), if id argument
is negative, it allows to easily check the correctness of the fix by
fuzzing the return value from ida_simple_get().

Fixes: ff2b1359 ("gpio: make the gpiochip a real device")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: default avatarVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent defeea5e

drivers/gpio/gpiolib.c

+3 −2
Original line number Diff line number Diff line
@@ -1295,7 +1295,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, 
	gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);

	if (!gdev->descs) {

		status = -ENOMEM;

		goto err_free_gdev;

		goto err_free_ida;

	}



	if (chip->ngpio == 0) {
@@ -1427,8 +1427,9 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, 
	kfree_const(gdev->label);

err_free_descs:

	kfree(gdev->descs);

err_free_gdev:

err_free_ida:

	ida_simple_remove(&gpio_ida, gdev->id);

err_free_gdev:

	/* failures here can mean systems won't boot... */

	pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,

	       gdev->base, gdev->base + gdev->ngpio - 1,