[PATCH] pinctrl: single: fix potential NULL dereference

[Maxim Korotkov]

Added checking of pointer "function" in pcs_set_mux().
pinmux_generic_get_function() can return NULL and the pointer
"function" was dereferenced without checking against NULL.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 571aec4df5b7 ("pinctrl: single: Use generic pinmux helpers for managing functions")
Signed-off-by: Maxim Korotkov <korotkov.maxim.s at gmail.com>
---
 drivers/pinctrl/pinctrl-single.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 67bec7ea0f8b..5655a2da5413 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -372,6 +372,8 @@ static int pcs_set_mux(struct pinctrl_dev *pctldev, unsigned fselector,
 	if (!pcs->fmask)
 		return 0;
 	function = pinmux_generic_get_function(pctldev, fselector);
+	if (!function)
+		return -EINVAL;
 	func = function->data;
 	if (!func)
 		return -EINVAL;
-- 
2.17.1