Commit 60d98457 authored by Liang He's avatar Liang He Committed by Zheng Zengkai
Browse files

gpio: gpiolib-of: Fix refcount bugs in of_mm_gpiochip_add_data() 

stable inclusion
from stable-v5.10.137
commit 26975d8ea96b478897f8cb91a9bc2395d7f3393c
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=26975d8ea96b478897f8cb91a9bc2395d7f3393c



--------------------------------

[ Upstream commit 5d07a692 ]

We should use of_node_get() when a new reference of device_node
is created. It is noted that the old reference stored in
'mm_gc->gc.of_node' should also be decreased.

This patch is based on the fact that there is a call site in function
'qe_add_gpiochips()' of src file 'drivers\soc\fsl\qe\gpio.c'. In this
function, of_mm_gpiochip_add_data() is contained in an iteration of
for_each_compatible_node() which will automatically increase and
decrease the refcount. So we need additional of_node_get() for the
reference escape in of_mm_gpiochip_add_data().

Fixes: a19e3da5 ("of/gpio: Kill of_gpio_chip and add members directly to gpio_chip")
Signed-off-by: default avatarLiang He <windhl@126.com>
Signed-off-by: default avatarBartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: default avatarWei Li <liwei391@huawei.com>
parent 130aebe1

drivers/gpio/gpiolib-of.c

+3 −1
Original line number Diff line number Diff line
@@ -863,7 +863,8 @@ int of_mm_gpiochip_add_data(struct device_node *np, 
	if (mm_gc->save_regs)

		mm_gc->save_regs(mm_gc);



	mm_gc->gc.of_node = np;

	of_node_put(mm_gc->gc.of_node);

	mm_gc->gc.of_node = of_node_get(np);



	ret = gpiochip_add_data(gc, data);

	if (ret)
@@ -871,6 +872,7 @@ int of_mm_gpiochip_add_data(struct device_node *np, 


	return 0;

err2:

	of_node_put(np);

	iounmap(mm_gc->regs);

err1:

	kfree(gc->label);