1 files changed, 22 insertions, 14 deletions

diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c
index b87f41187c6a..9365ce407426 100644
--- a/kernel/trace/trace_events_user.c
+++ b/kernel/trace/trace_events_user.c
@@ -50,18 +50,6 @@
 #define EVENT_STATUS_OTHER BIT(7)
 
 /*
- * User register flags are not allowed yet, keep them here until we are
- * ready to expose them out to the user ABI.
- */
-enum user_reg_flag {
-	/* Event will not delete upon last reference closing */
-	USER_EVENT_REG_PERSIST		= 1U << 0,
-
-	/* This value or above is currently non-ABI */
-	USER_EVENT_REG_MAX		= 1U << 1,
-};
-
-/*
  * Stores the system name, tables, and locks for a group of events. This
  * allows isolation for events by various means.
  */
@@ -220,6 +208,17 @@ static u32 user_event_key(char *name)
 	return jhash(name, strlen(name), 0);
 }
 
+static bool user_event_capable(u16 reg_flags)
+{
+	/* Persistent events require CAP_PERFMON / CAP_SYS_ADMIN */
+	if (reg_flags & USER_EVENT_REG_PERSIST) {
+		if (!perfmon_capable())
+			return false;
+	}
+
+	return true;
+}
+
 static struct user_event *user_event_get(struct user_event *user)
 {
 	refcount_inc(&user->refcnt);
@@ -1811,6 +1810,9 @@ static int user_event_free(struct dyn_event *ev)
 	if (!user_event_last_ref(user))
 		return -EBUSY;
 
+	if (!user_event_capable(user->reg_flags))
+		return -EPERM;
+
 	return destroy_user_event(user);
 }
 
@@ -1926,10 +1928,13 @@ static int user_event_parse(struct user_event_group *group, char *name,
 	int argc = 0;
 	char **argv;
 
-	/* User register flags are not ready yet */
-	if (reg_flags != 0 || flags != NULL)
+	/* Currently don't support any text based flags */
+	if (flags != NULL)
 		return -EINVAL;
 
+	if (!user_event_capable(reg_flags))
+		return -EPERM;
+
 	/* Prevent dyn_event from racing */
 	mutex_lock(&event_mutex);
 	user = find_user_event(group, name, &key);
@@ -2062,6 +2067,9 @@ static int delete_user_event(struct user_event_group *group, char *name)
 	if (!user_event_last_ref(user))
 		return -EBUSY;
 
+	if (!user_event_capable(user->reg_flags))
+		return -EPERM;
+
 	return destroy_user_event(user);
 }