diff --git a/sys/kern/kern_prot.c b/sys/kern/kern_prot.c
index 7929d73316d..f395f4a98e1 100644
--- a/sys/kern/kern_prot.c
+++ b/sys/kern/kern_prot.c
@@ -1995,10 +1995,9 @@ proc_set_cred_init(struct proc *p, struct ucred *newcred)
  * only used when the process is about to be freed, at which point it should
  * not be visible anymore).
  */
-struct ucred *
+void
 proc_set_cred(struct proc *p, struct ucred *newcred)
 {
-	struct ucred *oldcred;
 
 	MPASS(p->p_ucred != NULL);
 	if (newcred == NULL)
@@ -2006,11 +2005,9 @@ proc_set_cred(struct proc *p, struct ucred *newcred)
 	else
 		PROC_LOCK_ASSERT(p, MA_OWNED);
 
-	oldcred = p->p_ucred;
 	p->p_ucred = newcred;
 	if (newcred != NULL)
 		PROC_UPDATE_COW(p);
-	return (oldcred);
 }
 
 struct ucred *
diff --git a/sys/sys/ucred.h b/sys/sys/ucred.h
index 9713623de6c..43849aac76b 100644
--- a/sys/sys/ucred.h
+++ b/sys/sys/ucred.h
@@ -112,7 +112,7 @@ struct ucred	*crcopysafe(struct proc *p, struct ucred *cr);
 struct ucred	*crdup(struct ucred *cr);
 void	crextend(struct ucred *cr, int n);
 void	proc_set_cred_init(struct proc *p, struct ucred *cr);
-struct ucred	*proc_set_cred(struct proc *p, struct ucred *cr);
+void	proc_set_cred(struct proc *p, struct ucred *cr);
 void	crfree(struct ucred *cr);
 struct ucred	*crget(void);
 struct ucred	*crhold(struct ucred *cr);