[PATCH] pinctrl: fix Null pointer dereference

[clingfei <clf700383@xxxxxxxxx>]

pinmux_generic_get_function may returns NULL, and its retval is
dereferenced without check, which will cause a null pointer dereference.

Signed-off-by: clingfei <clf700383@xxxxxxxxx>
---
 drivers/pinctrl/pinctrl-th1520.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-th1520.c b/drivers/pinctrl/pinctrl-th1520.c
index 1bb78b212fd5..9331f4462480 100644
--- a/drivers/pinctrl/pinctrl-th1520.c
+++ b/drivers/pinctrl/pinctrl-th1520.c
@@ -798,6 +798,8 @@ static int th1520_pinmux_set_mux(struct
pinctrl_dev *pctldev,
    struct th1520_pinctrl *thp = pinctrl_dev_get_drvdata(pctldev);
    const struct function_desc *func =
pinmux_generic_get_function(pctldev, fsel);

+   if (!func)
+       return -EINVAL;
    return th1520_pinmux_set(thp, thp->desc.pins[gsel].number,
                 (uintptr_t)thp->desc.pins[gsel].drv_data & TH1520_PAD_MUXDATA,
                 (uintptr_t)func->data);
--
2.34.1