Merge branch 'for-4.16/remove-immediate' into for-linus
[muen/linux.git] / kernel / livepatch / core.c
index 41be6061b92f28650065019b583b48610f6d7240..3a4656fb7047c24bde87c644cb79902df2a6adba 100644 (file)
@@ -532,22 +532,24 @@ static ssize_t signal_store(struct kobject *kobj, struct kobj_attribute *attr,
        int ret;
        bool val;
 
        int ret;
        bool val;
 
-       patch = container_of(kobj, struct klp_patch, kobj);
-
-       /*
-        * klp_mutex lock is not grabbed here intentionally. It is not really
-        * needed. The race window is harmless and grabbing the lock would only
-        * hold the action back.
-        */
-       if (patch != klp_transition_patch)
-               return -EINVAL;
-
        ret = kstrtobool(buf, &val);
        if (ret)
                return ret;
 
        ret = kstrtobool(buf, &val);
        if (ret)
                return ret;
 
-       if (val)
-               klp_send_signals();
+       if (!val)
+               return count;
+
+       mutex_lock(&klp_mutex);
+
+       patch = container_of(kobj, struct klp_patch, kobj);
+       if (patch != klp_transition_patch) {
+               mutex_unlock(&klp_mutex);
+               return -EINVAL;
+       }
+
+       klp_send_signals();
+
+       mutex_unlock(&klp_mutex);
 
        return count;
 }
 
        return count;
 }
@@ -559,22 +561,24 @@ static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr,
        int ret;
        bool val;
 
        int ret;
        bool val;
 
-       patch = container_of(kobj, struct klp_patch, kobj);
-
-       /*
-        * klp_mutex lock is not grabbed here intentionally. It is not really
-        * needed. The race window is harmless and grabbing the lock would only
-        * hold the action back.
-        */
-       if (patch != klp_transition_patch)
-               return -EINVAL;
-
        ret = kstrtobool(buf, &val);
        if (ret)
                return ret;
 
        ret = kstrtobool(buf, &val);
        if (ret)
                return ret;
 
-       if (val)
-               klp_force_transition();
+       if (!val)
+               return count;
+
+       mutex_lock(&klp_mutex);
+
+       patch = container_of(kobj, struct klp_patch, kobj);
+       if (patch != klp_transition_patch) {
+               mutex_unlock(&klp_mutex);
+               return -EINVAL;
+       }
+
+       klp_force_transition();
+
+       mutex_unlock(&klp_mutex);
 
        return count;
 }
 
        return count;
 }