PM / QoS: return -EINVAL for bogus strings

Dan Carpenter · rafaeljw · commit 2ca30331c156 · 2017-07-12T14:42:37.000+02:00
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: 2d984ad (PM / QoS: Introcuce latency tolerance device PM QoS type) Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: 3.15+ <stable@vger.kernel.org> # 3.15+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
@@ -272,6 +272,8 @@ static ssize_t pm_qos_latency_tolerance_store(struct device *dev,
 			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;

Original file line number	Diff line number	Diff line change
`@@ -272,6 +272,8 @@ static ssize_t pm_qos_latency_tolerance_store(struct device *dev,`
`272`	`272`	`value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;`
`273`	`273`	`else if (!strcmp(buf, "any") \|\| !strcmp(buf, "any\n"))`
`274`	`274`	`value = PM_QOS_LATENCY_ANY;`
	`275`	`+ else`
	`276`	`+ return -EINVAL;`
`275`	`277`	`}`
`276`	`278`	`ret = dev_pm_qos_update_user_latency_tolerance(dev, value);`
`277`	`279`	`return ret < 0 ? ret : n;`