--- sys/compat/linux/linux_misc.c.orig
+++ sys/compat/linux/linux_misc.c
@@ -1304,9 +1304,11 @@
 	if (error)
 		goto out;
 	newcred = crget();
+	crextend(newcred, ngrp + 1);
 	p = td->td_proc;
 	PROC_LOCK(p);
-	oldcred = crcopysafe(p, newcred);
+	oldcred = p->p_ucred;
+	crcopy(newcred, oldcred);
 
 	/*
 	 * cr_groups[0] holds egid. Setting the whole set from
--- sys/kern/kern_prot.c.orig
+++ sys/kern/kern_prot.c
@@ -88,7 +88,6 @@
 
 SYSCTL_NODE(_security, OID_AUTO, bsd, CTLFLAG_RW, 0, "BSD security policy");
 
-static void crextend(struct ucred *cr, int n);
 static void crsetgroups_locked(struct ucred *cr, int ngrp,
     gid_t *groups);
 
@@ -1997,7 +1996,7 @@
 /*
  * Extend the passed in credential to hold n items.
  */
-static void
+void
 crextend(struct ucred *cr, int n)
 {
 	int cnt;
--- sys/sys/ucred.h.orig
+++ sys/sys/ucred.h
@@ -105,6 +105,7 @@
 void	crcopy(struct ucred *dest, struct ucred *src);
 struct ucred	*crcopysafe(struct proc *p, struct ucred *cr);
 struct ucred	*crdup(struct ucred *cr);
+void	crextend(struct ucred *cr, int n);
 void	cred_update_thread(struct thread *td);
 void	crfree(struct ucred *cr);
 struct ucred	*crget(void);