1 files changed, 24 insertions, 19 deletions

diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index 75bf1bcb4a8a..d1fa19773cc8 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -9,7 +9,7 @@
  *
  */
 
-
+#include <linux/security.h>
 #include <linux/list.h>
 #include <linux/slab.h>
 #include <linux/rbtree.h>
@@ -72,9 +72,7 @@ static void destroy_session(struct stat_session *session)
 	kfree(session);
 }
 
-typedef int (*cmp_stat_t)(void *, void *);
-
-static int insert_stat(struct rb_root *root, void *stat, cmp_stat_t cmp)
+static int insert_stat(struct rb_root *root, void *stat, cmp_func_t cmp)
 {
 	struct rb_node **new = &(root->rb_node), *parent = NULL;
 	struct stat_node *data;
@@ -112,7 +110,7 @@ static int insert_stat(struct rb_root *root, void *stat, cmp_stat_t cmp)
  * This one will force an insertion as right-most node
  * in the rbtree.
  */
-static int dummy_cmp(void *p1, void *p2)
+static int dummy_cmp(const void *p1, const void *p2)
 {
 	return -1;
 }
@@ -238,6 +236,10 @@ static int tracing_stat_open(struct inode *inode, struct file *file)
 	struct seq_file *m;
 	struct stat_session *session = inode->i_private;
 
+	ret = security_locked_down(LOCKDOWN_TRACEFS);
+	if (ret)
+		return ret;
+
 	ret = stat_seq_init(session);
 	if (ret)
 		return ret;
@@ -278,18 +280,22 @@ static int tracing_stat_init(void)
 
 	d_tracing = tracing_init_dentry();
 	if (IS_ERR(d_tracing))
-		return 0;
+		return -ENODEV;
 
 	stat_dir = tracefs_create_dir("trace_stat", d_tracing);
-	if (!stat_dir)
+	if (!stat_dir) {
 		pr_warn("Could not create tracefs 'trace_stat' entry\n");
+		return -ENOMEM;
+	}
 	return 0;
 }
 
 static int init_stat_file(struct stat_session *session)
 {
-	if (!stat_dir && tracing_stat_init())
-		return -ENODEV;
+	int ret;
+
+	if (!stat_dir && (ret = tracing_stat_init()))
+		return ret;
 
 	session->file = tracefs_create_file(session->ts->name, 0644,
 					    stat_dir,
@@ -302,7 +308,7 @@ static int init_stat_file(struct stat_session *session)
 int register_stat_tracer(struct tracer_stat *trace)
 {
 	struct stat_session *session, *node;
-	int ret;
+	int ret = -EINVAL;
 
 	if (!trace)
 		return -EINVAL;
@@ -313,17 +319,15 @@ int register_stat_tracer(struct tracer_stat *trace)
 	/* Already registered? */
 	mutex_lock(&all_stat_sessions_mutex);
 	list_for_each_entry(node, &all_stat_sessions, session_list) {
-		if (node->ts == trace) {
-			mutex_unlock(&all_stat_sessions_mutex);
-			return -EINVAL;
-		}
+		if (node->ts == trace)
+			goto out;
 	}
-	mutex_unlock(&all_stat_sessions_mutex);
 
+	ret = -ENOMEM;
 	/* Init the session */
 	session = kzalloc(sizeof(*session), GFP_KERNEL);
 	if (!session)
-		return -ENOMEM;
+		goto out;
 
 	session->ts = trace;
 	INIT_LIST_HEAD(&session->session_list);
@@ -332,15 +336,16 @@ int register_stat_tracer(struct tracer_stat *trace)
 	ret = init_stat_file(session);
 	if (ret) {
 		destroy_session(session);
-		return ret;
+		goto out;
 	}
 
+	ret = 0;
 	/* Register */
-	mutex_lock(&all_stat_sessions_mutex);
 	list_add_tail(&session->session_list, &all_stat_sessions);
+ out:
 	mutex_unlock(&all_stat_sessions_mutex);
 
-	return 0;
+	return ret;
 }
 
 void unregister_stat_tracer(struct tracer_stat *trace)