From: Minsung Kim <ms925.kim@samsung.com>
Date: Sun, 19 Jan 2014 05:32:42 +0000 (+0900)
Subject: cpufreq: interactive: fix NULL pointer dereference at sysfs ops
X-Git-Tag: firefly_0821_release~2958^2~256
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8385286d765f9bd4cdb3eff094a000af32eb8c3b;p=firefly-linux-kernel-4.4.55.git

cpufreq: interactive: fix NULL pointer dereference at sysfs ops

sysfs ops for target_loads and above_hispeed_delay can be called before
initializing tunables at CPUFREQ_GOV_POLICY_INIT. Create sysfs entries after
initialization.

Change-Id: I50356198d7629731c0d32a3066d61fe8354e0001
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
---

diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c
index 9f63bd1e4fee..8297ac69863b 100644
--- a/drivers/cpufreq/cpufreq_interactive.c
+++ b/drivers/cpufreq/cpufreq_interactive.c
@@ -1178,13 +1178,6 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
 			return -ENOMEM;
 		}
 
-		rc = sysfs_create_group(get_governor_parent_kobj(policy),
-				get_sysfs_attr());
-		if (rc) {
-			kfree(tunables);
-			return rc;
-		}
-
 		tunables->usage_count = 1;
 		tunables->above_hispeed_delay = default_above_hispeed_delay;
 		tunables->nabove_hispeed_delay =
@@ -1200,16 +1193,26 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
 		spin_lock_init(&tunables->target_loads_lock);
 		spin_lock_init(&tunables->above_hispeed_delay_lock);
 
+		policy->governor_data = tunables;
+		if (!have_governor_per_policy())
+			common_tunables = tunables;
+
+		rc = sysfs_create_group(get_governor_parent_kobj(policy),
+				get_sysfs_attr());
+		if (rc) {
+			kfree(tunables);
+			policy->governor_data = NULL;
+			if (!have_governor_per_policy())
+				common_tunables = NULL;
+			return rc;
+		}
+
 		if (!policy->governor->initialized) {
 			idle_notifier_register(&cpufreq_interactive_idle_nb);
 			cpufreq_register_notifier(&cpufreq_notifier_block,
 					CPUFREQ_TRANSITION_NOTIFIER);
 		}
 
-		policy->governor_data = tunables;
-		if (!have_governor_per_policy())
-			common_tunables = tunables;
-
 		break;
 
 	case CPUFREQ_GOV_POLICY_EXIT: