[PATCH 4.12 80/84] PM / QoS: return -EINVAL for bogus strings

From: Greg Kroah-Hartman
Date: Wed Jul 19 2017 - 05:47:54 EST


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

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

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 2ca30331c156ca9e97643ad05dd8930b8fe78b01 upstream.

In the current code, if the user accidentally writes a bogus command to
this sysfs file, then we set the latency tolerance to an uninitialized
variable.

Fixes: 2d984ad132a8 (PM / QoS: Introcuce latency tolerance device PM QoS type)
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/base/power/sysfs.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -272,6 +272,8 @@ static ssize_t pm_qos_latency_tolerance_
value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
else if (!strcmp(buf, "any") || !strcmp(buf, "any\n"))
value = PM_QOS_LATENCY_ANY;
+ else
+ return -EINVAL;
}
ret = dev_pm_qos_update_user_latency_tolerance(dev, value);
return ret < 0 ? ret : n;