[PATCH v6 6/6] keys: kill task_struct->replacement_session_keyring

[Oleg Nesterov <oleg@redhat.com>]

Kill the no longer used task_struct->replacement_session_keyring,
update copy_creds() and exit_creds().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
 include/linux/sched.h |    2 --
 kernel/cred.c         |    9 ---------
 2 files changed, 0 insertions(+), 11 deletions(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index e36edfb..ac04a02 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1402,8 +1402,6 @@ struct task_struct {
 					 * credentials (COW) */
 	const struct cred __rcu *cred;	/* effective (overridable) subjective task
 					 * credentials (COW) */
-	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
-
 	char comm[TASK_COMM_LEN]; /* executable name excluding path
 				     - access with [gs]et_task_comm (which lock
 				       it with task_lock())
diff --git a/kernel/cred.c b/kernel/cred.c
index e70683d..9570736 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -198,13 +198,6 @@ void exit_creds(struct task_struct *tsk)
 	validate_creds(cred);
 	alter_cred_subscribers(cred, -1);
 	put_cred(cred);
-
-	cred = (struct cred *) tsk->replacement_session_keyring;
-	if (cred) {
-		tsk->replacement_session_keyring = NULL;
-		validate_creds(cred);
-		put_cred(cred);
-	}
 }
 
 /**
@@ -386,8 +379,6 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
 	struct cred *new;
 	int ret;
 
-	p->replacement_session_keyring = NULL;
-
 	if (
 #ifdef CONFIG_KEYS
 		!p->cred->thread_keyring &&
-- 
1.5.5.1