[PATCH 1/2] pinctrl: renesas: fix possible null-ptr-deref in sh_pfc_map_resources()

From: Yang Yingliang <yangyingliang@huawei.com>
To: <linux-kernel@vger.kernel.org>, <linux-gpio@vger.kernel.org>,
	<linux-renesas-soc@vger.kernel.org>
Cc: <linus.walleij@linaro.org>, <geert+renesas@glider.be>
Subject: [PATCH 1/2] pinctrl: renesas: fix possible null-ptr-deref in sh_pfc_map_resources()
Date: Fri, 29 Apr 2022 16:26:36 +0800	[thread overview]
Message-ID: <20220429082637.1308182-1-yangyingliang@huawei.com> (raw)

It will cause null-ptr-deref when using 'res', if platform_get_resource()
returns NULL, so move using 'res' after devm_ioremap_resource() that
will check it to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.

Fixes: c7977ec4a336 ("pinctrl: sh-pfc: Convert to platform_get_*()")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
---
 drivers/pinctrl/renesas/core.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/pinctrl/renesas/core.c b/drivers/pinctrl/renesas/core.c
index d0d4714731c1..3d8bf521c3e7 100644
--- a/drivers/pinctrl/renesas/core.c
+++ b/drivers/pinctrl/renesas/core.c
@@ -71,12 +71,11 @@ static int sh_pfc_map_resources(struct sh_pfc *pfc,
 
 	/* Fill them. */
 	for (i = 0; i < num_windows; i++) {
-		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
-		windows->phys = res->start;
-		windows->size = resource_size(res);
-		windows->virt = devm_ioremap_resource(pfc->dev, res);
+		windows->virt = devm_platform_get_and_ioremap_resource(pdev, i, &res);
 		if (IS_ERR(windows->virt))
 			return -ENOMEM;
+		windows->phys = res->start;
+		windows->size = resource_size(res);
 		windows++;
 	}
 	for (i = 0; i < num_irqs; i++)
-- 
2.25.1

