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 06a3c1ef8eee..952544ca0d84 100644 --- a/drivers/platform/x86/hp-wmi.c +++ b/drivers/platform/x86/hp-wmi.c @@ -474,8 +474,14 @@ 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