[PATCH v3 1/1] pinctrl: freescale: Fix a memory out of bounds when num_configs is 1

Xiaolei Wang
2023-05-04T00:34:39Z

The config passed in by pad wakeup is 1, When num_configs is 1,
configs[1] should not be obtained, which will generate the
following memory out-of-bounds situation:

BUG: KASAN: stack out of bounds in imx_pinconf_set_scu+0x9c/0x160
Read size 8 at address ffff8000104c7558 by task sh/664
CPU: 3 PID: 664 Communication: sh Tainted: G WC 6.1.20 #1
Hardware name: Freescale i.MX8QM MEK (DT)
Call trace:
dump_backtrace.part.0+0xe0/0xf0
show stack+0x18/0x30
dump_stack_lvl+0x64/0x80
print report +0x154/0x458
kasan_report+0xb8/0x100
__asan_load8+0x80/0xac
imx_pinconf_set_scu+0x9c/0x160
imx_pinconf_set+0x6c/0x214
pinconf_set_config+0x68/0x90
pinctrl_gpio_set_config+0x138/0x170
gpiochip_generic_config+0x44/0x60
mxc_gpio_set_pad_wakeup+0x100/0x140

Fixes: f60c9eac54af ("gpio: mxc: enable pad wakeup on i.MX8x platforms")
Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
---
drivers/pinctrl/freescale/pinctrl-scu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/freescale/pinctrl-scu.c b/drivers/pinctrl/freescale/pinctrl-scu.c
index ea261b6e7458..3b252d684d72 100644
--- a/drivers/pinctrl/freescale/pinctrl-scu.c
+++ b/drivers/pinctrl/freescale/pinctrl-scu.c
@@ -90,7 +90,7 @@ int imx_pinconf_set_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
struct imx_sc_msg_req_pad_set msg;
struct imx_sc_rpc_msg *hdr = &msg.hdr;
unsigned int mux = configs[0];
- unsigned int conf = configs[1];
+ unsigned int conf;
unsigned int val;
int ret;

@@ -115,6 +115,7 @@ int imx_pinconf_set_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
* Set mux and conf together in one IPC call
*/
WARN_ON(num_configs != 2);
+ conf = configs[1];

val = conf | BM_PAD_CTL_IFMUX_ENABLE | BM_PAD_CTL_GP_ENABLE;
val |= mux << BP_PAD_CTL_IFMUX;
--
2.25.1