From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	patches@lists.linux.dev,
	Jiayu Du <jiayu.riscv@isrc.iscas.ac.cn>,
	Linus Walleij <linusw@kernel.org>,
	Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.18 491/641] pinctrl: canaan: k230: Fix NULL pointer dereference when parsing devicetree
Date: Tue, 24 Feb 2026 17:23:37 -0800
Message-ID: <20260225012400.412715934@linuxfoundation.org>
In-Reply-To: <20260225012348.915798704@linuxfoundation.org>
References: <20260225012348.915798704@linuxfoundation.org>
User-Agent: quilt/0.69
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

6.18-stable review patch.  If anyone has any objections, please let me know.

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

From: Jiayu Du <jiayu.riscv@isrc.iscas.ac.cn>

[ Upstream commit d8c128fb6c2277d95f3f6a4ce28b82c8370031f6 ]

When probing the k230 pinctrl driver, the kernel triggers a NULL pointer
dereference. The crash trace showed:
[    0.732084] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000068
[    0.740737] ...
[    0.776296] epc : k230_pinctrl_probe+0x1be/0x4fc

In k230_pinctrl_parse_functions(), we attempt to retrieve the device
pointer via info->pctl_dev->dev, but info->pctl_dev is only initialized
after k230_pinctrl_parse_dt() completes.

At the time of DT parsing, info->pctl_dev is still NULL, leading to
the invalid dereference of info->pctl_dev->dev.

Use the already available device pointer from platform_device
instead of accessing through uninitialized pctl_dev.

Fixes: d94a32ac688f ("pinctrl: canaan: k230: Fix order of DT parse and pinctrl register")
Signed-off-by: Jiayu Du <jiayu.riscv@isrc.iscas.ac.cn>
Signed-off-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pinctrl/pinctrl-k230.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-k230.c b/drivers/pinctrl/pinctrl-k230.c
index d716f23d837f7..20f7c0f70eb77 100644
--- a/drivers/pinctrl/pinctrl-k230.c
+++ b/drivers/pinctrl/pinctrl-k230.c
@@ -65,6 +65,7 @@ struct k230_pmx_func {
 };
 
 struct k230_pinctrl {
+	struct device		*dev;
 	struct pinctrl_desc	pctl;
 	struct pinctrl_dev	*pctl_dev;
 	struct regmap		*regmap_base;
@@ -470,7 +471,7 @@ static int k230_pinctrl_parse_groups(struct device_node *np,
 				     struct k230_pinctrl *info,
 				     unsigned int index)
 {
-	struct device *dev = info->pctl_dev->dev;
+	struct device *dev = info->dev;
 	const __be32 *list;
 	int size, i, ret;
 
@@ -511,7 +512,7 @@ static int k230_pinctrl_parse_functions(struct device_node *np,
 					struct k230_pinctrl *info,
 					unsigned int index)
 {
-	struct device *dev = info->pctl_dev->dev;
+	struct device *dev = info->dev;
 	struct k230_pmx_func *func;
 	struct k230_pin_group *grp;
 	static unsigned int idx, i;
@@ -596,6 +597,8 @@ static int k230_pinctrl_probe(struct platform_device *pdev)
 	if (!info)
 		return -ENOMEM;
 
+	info->dev = dev;
+
 	pctl = &info->pctl;
 
 	pctl->name	= "k230-pinctrl";
-- 
2.51.0