[PATCH] Input: mtk-pmic-keys - fix possible null pointer dereference

[PATCH] Input: mtk-pmic-keys - fix possible null pointer dereference

[Gary Bisson]

In mtk_pmic_keys_probe, the regs parameter is only set if the button is
parsed in the device tree. However, on hardware where the button is left
floating, that node will most likely be removed not to enable that
input. In that case the code will try to dereference a null pointer.

Let's use the regs struct instead as it is defined for all supported
platforms. Note that it is ok setting the key reg even if that latter is
disabled as the interrupt won't be enabled anyway.

Fixes: b581acb49aec5 ("Input: mtk-pmic-keys - transfer per-key bit in
mtk_pmic_keys_regs")

Signed-off-by: Gary Bisson <bisson.gary@gmail.com>
---
 drivers/input/keyboard/mtk-pmic-keys.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/input/keyboard/mtk-pmic-keys.c b/drivers/input/keyboard/mtk-pmic-keys.c
index 5ad6be9141603..061d48350df66 100644
--- a/drivers/input/keyboard/mtk-pmic-keys.c
+++ b/drivers/input/keyboard/mtk-pmic-keys.c
@@ -147,8 +147,8 @@ static void mtk_pmic_keys_lp_reset_setup(struct mtk_pmic_keys *keys,
 	u32 value, mask;
 	int error;
 
-	kregs_home = keys->keys[MTK_PMIC_HOMEKEY_INDEX].regs;
-	kregs_pwr = keys->keys[MTK_PMIC_PWRKEY_INDEX].regs;
+	kregs_home = &regs->keys_regs[MTK_PMIC_HOMEKEY_INDEX];
+	kregs_pwr = &regs->keys_regs[MTK_PMIC_PWRKEY_INDEX];
 
 	error = of_property_read_u32(keys->dev->of_node, "power-off-time-sec",
 				     &long_press_debounce);
-- 
2.47.2

Re: [PATCH] Input: mtk-pmic-keys - fix possible null pointer dereference

[Dmitry Torokhov]

On Tue, Apr 29, 2025 at 02:28:15PM +0200, Gary Bisson wrote:
> In mtk_pmic_keys_probe, the regs parameter is only set if the button is
> parsed in the device tree. However, on hardware where the button is left
> floating, that node will most likely be removed not to enable that
> input. In that case the code will try to dereference a null pointer.
> 
> Let's use the regs struct instead as it is defined for all supported
> platforms. Note that it is ok setting the key reg even if that latter is
> disabled as the interrupt won't be enabled anyway.
> 
> Fixes: b581acb49aec5 ("Input: mtk-pmic-keys - transfer per-key bit in
> mtk_pmic_keys_regs")
> 
> Signed-off-by: Gary Bisson <bisson.gary@gmail.com>

Applied, thank you.

-- 
Dmitry