[PATCH 3/4] timens: Use mutex guard in proc_timens_set_offset()

[Thomas Weißschuh]

Simplify the logic in proc_timens_set_offset() by converting the mutex
usage to a guard().

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
---
 kernel/time/namespace.c | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c
index ae9a3a5d53ab..fbf026e63104 100644
--- a/kernel/time/namespace.c
+++ b/kernel/time/namespace.c
@@ -270,7 +270,7 @@ int proc_timens_set_offset(struct file *file, struct task_struct *p,
 	struct ns_common *ns;
 	struct time_namespace *time_ns __free(time_ns) = NULL;
 	struct timespec64 tp;
-	int i, err;
+	int i;
 
 	ns = timens_for_children_get(p);
 	if (!ns)
@@ -307,13 +307,10 @@ int proc_timens_set_offset(struct file *file, struct task_struct *p,
 			return -ERANGE;
 	}
 
-	mutex_lock(&timens_offset_lock);
-	if (time_ns->frozen_offsets) {
-		err = -EACCES;
-		goto out_unlock;
-	}
+	guard(mutex)(&timens_offset_lock);
+	if (time_ns->frozen_offsets)
+		return -EACCES;
 
-	err = 0;
 	/* Don't report errors after this line */
 	for (i = 0; i < noffsets; i++) {
 		struct proc_timens_offset *off = &offsets[i];
@@ -331,10 +328,7 @@ int proc_timens_set_offset(struct file *file, struct task_struct *p,
 		*offset = off->val;
 	}
 
-out_unlock:
-	mutex_unlock(&timens_offset_lock);
-
-	return err;
+	return 0;
 }
 
 const struct proc_ns_operations timens_operations = {

-- 
2.53.0