diff --git a/sys/kern/kern_prot.c b/sys/kern/kern_prot.c
--- a/sys/kern/kern_prot.c
+++ b/sys/kern/kern_prot.c
@@ -422,7 +422,7 @@
  *	pid must be in same session (EPERM)
  *	pid can't have done an exec (EACCES)
  * if pgid != pid
- * 	there must exist some pid in same session having pgid (EPERM)
+ *	there must exist some pid in same session having pgid (EPERM)
  * pid must not be session leader (EPERM)
  */
 #ifndef _SYS_SYSPROTO_H_
@@ -2792,10 +2792,6 @@
 
 	MPASS(oldcred != NULL);
 	PROC_LOCK_ASSERT(p, MA_OWNED);
-	KASSERT(newcred->cr_users == 0, ("%s: users %d not 0 on cred %p",
-	    __func__, newcred->cr_users, newcred));
-	KASSERT(newcred->cr_ref == 1, ("%s: ref %ld not 1 on cred %p",
-	    __func__, newcred->cr_ref, newcred));
 
 	if (newcred->cr_ruidinfo != oldcred->cr_ruidinfo) {
 		/*
@@ -2821,8 +2817,10 @@
 	    __func__, oldcred->cr_users, oldcred));
 	oldcred->cr_users--;
 	mtx_unlock(&oldcred->cr_mtx);
+	mtx_lock(&newcred->cr_mtx);
+	++newcred->cr_users;
+	mtx_unlock(&newcred->cr_mtx);
 	p->p_ucred = newcred;
-	newcred->cr_users = 1;
 	PROC_UPDATE_COW(p);
 	if (newcred->cr_ruidinfo != oldcred->cr_ruidinfo)
 		(void)chgproccnt(oldcred->cr_ruidinfo, -1, 0);