fork: Use RCU_INIT_POINTER() instead of rcu_access_pointer()

Madhuparna Bhowmik · Christian Brauner · commit 0c282b068eb2 · 2020-02-28T13:34:36.000+01:00
Use RCU_INIT_POINTER() instead of rcu_access_pointer() in copy_sighand(). Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> [christian.brauner@ubuntu.com: edit commit message] Link: https://lore.kernel.org/r/20200127175821.10833-1-madhuparnabhowmik10@gmail.com Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
diff --git a/kernel/fork.c b/kernel/fork.c
@@ -1508,7 +1508,7 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
 		return 0;
 	}
 	sig = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);
-	rcu_assign_pointer(tsk->sighand, sig);
+	RCU_INIT_POINTER(tsk->sighand, sig);
 	if (!sig)
 		return -ENOMEM;
 

Original file line number	Diff line number	Diff line change
`@@ -1508,7 +1508,7 @@ static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)`
`1508`	`1508`	`return 0;`
`1509`	`1509`	`}`
`1510`	`1510`	`sig = kmem_cache_alloc(sighand_cachep, GFP_KERNEL);`
`1511`		`- rcu_assign_pointer(tsk->sighand, sig);`
	`1511`	`+ RCU_INIT_POINTER(tsk->sighand, sig);`
`1512`	`1512`	`if (!sig)`
`1513`	`1513`	`return -ENOMEM;`
`1514`	`1514`