[PATCH AUTOSEL 5.4 163/175] platform/x86: hp-wmi: Convert simple_strtoul() to kstrtou32()

From: Sasha Levin
Date: Mon Jun 08 2020 - 19:28:00 EST


From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

[ Upstream commit 5cdc45ed3948042f0d73c6fec5ee9b59e637d0d2 ]

First of all, unsigned long can overflow u32 value on 64-bit machine.
Second, simple_strtoul() doesn't check for overflow in the input.

Convert simple_strtoul() to kstrtou32() to eliminate above issues.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/platform/x86/hp-wmi.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/x86/hp-wmi.c b/drivers/platform/x86/hp-wmi.c
index a881b709af25..a44a2ec33287 100644
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -461,8 +461,14 @@ static ssize_t postcode_show(struct device *dev, struct device_attribute *attr,
static ssize_t als_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
- u32 tmp = simple_strtoul(buf, NULL, 10);
- int ret = hp_wmi_perform_query(HPWMI_ALS_QUERY, HPWMI_WRITE, &tmp,
+ u32 tmp;
+ int ret;
+
+ ret = kstrtou32(buf, 10, &tmp);
+ if (ret)
+ return ret;
+
+ ret = hp_wmi_perform_query(HPWMI_ALS_QUERY, HPWMI_WRITE, &tmp,
sizeof(tmp), sizeof(tmp));
if (ret)
return ret < 0 ? ret : -EINVAL;
--
2.25.1