static int xfrm_bundle_ok(struct xfrm_dst *first)
{
	struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
	struct dst_entry *dst = &first->u.dst;
	struct xfrm_dst *xdst;
	int start_from, nr;
	u32 mtu;

	if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
	    (dst->dev && !netif_running(dst->dev)))
		return 0;

	if (dst->flags & DST_XFRM_QUEUE)
		return 1;

	start_from = nr = 0;
	do {
		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;

		if (dst->xfrm->km.state != XFRM_STATE_VALID)
			return 0;
		if (xdst->xfrm_genid != dst->xfrm->genid)
			return 0;
		if (xdst->num_pols > 0 &&
		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
			return 0;

		bundle[nr++] = xdst;

		mtu = dst_mtu(xfrm_dst_child(dst));
		if (xdst->child_mtu_cached != mtu) {
			start_from = nr;
			xdst->child_mtu_cached = mtu;
		}

		if (!dst_check(xdst->route, xdst->route_cookie))
			return 0;
		mtu = dst_mtu(xdst->route);
		if (xdst->route_mtu_cached != mtu) {
			start_from = nr;
			xdst->route_mtu_cached = mtu;
		}

		dst = xfrm_dst_child(dst);
	} while (dst->xfrm);

	if (likely(!start_from))
		return 1;

	xdst = bundle[start_from - 1];
	mtu = xdst->child_mtu_cached;
	while (start_from--) {
		dst = &xdst->u.dst;

		mtu = xfrm_state_mtu(dst->xfrm, mtu);
		if (mtu > xdst->route_mtu_cached)
			mtu = xdst->route_mtu_cached;
		dst_metric_set(dst, RTAX_MTU, mtu);
		if (!start_from)
			break;

		xdst = bundle[start_from - 1];
		xdst->child_mtu_cached = mtu;
	}

	return 1;
}


static int __net_init xfrm_policy_init(struct net *net)
{
	unsigned int hmask, sz;
	int dir, err;

	if (net_eq(net, &init_net)) {
		xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache",
					   sizeof(struct xfrm_dst),
					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
					   NULL);
		err = rhashtable_init(&xfrm_policy_inexact_table,
				      &xfrm_pol_inexact_params);
		BUG_ON(err);
	}

	hmask = 8 - 1;
	sz = (hmask+1) * sizeof(struct hlist_head);

	net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
	if (!net->xfrm.policy_byidx)
		goto out_byidx;
	net->xfrm.policy_idx_hmask = hmask;

	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
		struct xfrm_policy_hash *htab;

		net->xfrm.policy_count[dir] = 0;
		net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
		INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);

		htab = &net->xfrm.policy_bydst[dir];
		htab->table = xfrm_hash_alloc(sz);
		if (!htab->table)
			goto out_bydst;
		htab->hmask = hmask;
		htab->dbits4 = 32;
		htab->sbits4 = 32;
		htab->dbits6 = 128;
		htab->sbits6 = 128;
	}
	net->xfrm.policy_hthresh.lbits4 = 32;
	net->xfrm.policy_hthresh.rbits4 = 32;
	net->xfrm.policy_hthresh.lbits6 = 128;
	net->xfrm.policy_hthresh.rbits6 = 128;

	seqlock_init(&net->xfrm.policy_hthresh.lock);

	INIT_LIST_HEAD(&net->xfrm.policy_all);
	INIT_LIST_HEAD(&net->xfrm.inexact_bins);
	INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
	INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
	return 0;

out_bydst:
	for (dir--; dir >= 0; dir--) {
		struct xfrm_policy_hash *htab;

		htab = &net->xfrm.policy_bydst[dir];
		xfrm_hash_free(htab->table, sz);
	}
	xfrm_hash_free(net->xfrm.policy_byidx, sz);
out_byidx:
	return -ENOMEM;
}

xfrm: xfrm_policy: fix a possible double xfrm_pols_put() in xfrm_bundle_lookup()

xfrm_policy_lookup() will call xfrm_pol_hold_rcu() to get a refcount of
pols[0]. This refcount can be dropped in xfrm_expand_policies() when
xfrm_expand_policies() return error. pols[0]'s refcount is balanced in
here. But xfrm_bundle_lookup() will also call xfrm_pols_put() with
num_pols == 1 to drop this refcount when xfrm_expand_policies() return
error.

This patch also fix an illegal address access. pols[0] will save a error
point when xfrm_policy_lookup fails. This lead to xfrm_pols_put to resolve
an illegal address in xfrm_bundle_lookup's error path.

Fix these by setting num_pols = 0 in xfrm_expand_policies()'s error path.

Fixes: 80c802f3073e ("xfrm: cache bundles instead of policies for outgoing flows")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>


static int xfrm_get_tos(const struct flowi *fl, int family)
{
	if (family == AF_INET)
		return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos;

	return 0;
}


static void xfrm_policy_kill(struct xfrm_policy *policy)
{
	write_lock_bh(&policy->lock);
	policy->walk.dead = 1;
	write_unlock_bh(&policy->lock);

	atomic_inc(&policy->genid);

	if (del_timer(&policy->polq.hold_timer))
		xfrm_pol_put(policy);
	skb_queue_purge(&policy->polq.hold_queue);

	if (del_timer(&policy->timer))
		xfrm_pol_put(policy);

	xfrm_pol_put(policy);
}


static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
					      const struct flowi *fl,
					      u16 family, u8 dir, u32 if_id)
{
#ifdef CONFIG_XFRM_SUB_POLICY
	struct xfrm_policy *pol;

	pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
					dir, if_id);
	if (pol != NULL)
		return pol;
#endif
	return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
					 dir, if_id);
}


int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
{
	struct net *net = sock_net(sk);
	struct xfrm_policy *old_pol;

#ifdef CONFIG_XFRM_SUB_POLICY
	if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
		return -EINVAL;
#endif

	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	old_pol = rcu_dereference_protected(sk->sk_policy[dir],
				lockdep_is_held(&net->xfrm.xfrm_policy_lock));
	if (pol) {
		pol->curlft.add_time = ktime_get_real_seconds();
		pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
		xfrm_sk_policy_link(pol, dir);
	}
	rcu_assign_pointer(sk->sk_policy[dir], pol);
	if (old_pol) {
		if (pol)
			xfrm_policy_requeue(old_pol, pol);

		/* Unlinking succeeds always. This is the only function
		 * allowed to delete or replace socket policy.
		 */
		xfrm_sk_policy_unlink(old_pol, dir);
	}
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);

	if (old_pol) {
		xfrm_policy_kill(old_pol);
	}
	return 0;
}


static void xfrm_hash_rebuild(struct work_struct *work)
{
	struct net *net = container_of(work, struct net,
				       xfrm.policy_hthresh.work);
	unsigned int hmask;
	struct xfrm_policy *pol;
	struct xfrm_policy *policy;
	struct hlist_head *chain;
	struct hlist_head *odst;
	struct hlist_node *newpos;
	int i;
	int dir;
	unsigned seq;
	u8 lbits4, rbits4, lbits6, rbits6;

	mutex_lock(&hash_resize_mutex);

	/* read selector prefixlen thresholds */
	do {
		seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);

		lbits4 = net->xfrm.policy_hthresh.lbits4;
		rbits4 = net->xfrm.policy_hthresh.rbits4;
		lbits6 = net->xfrm.policy_hthresh.lbits6;
		rbits6 = net->xfrm.policy_hthresh.rbits6;
	} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));

	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);

	/* make sure that we can insert the indirect policies again before
	 * we start with destructive action.
	 */
	list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
		struct xfrm_pol_inexact_bin *bin;
		u8 dbits, sbits;

		dir = xfrm_policy_id2dir(policy->index);
		if (policy->walk.dead || dir >= XFRM_POLICY_MAX)
			continue;

		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
			if (policy->family == AF_INET) {
				dbits = rbits4;
				sbits = lbits4;
			} else {
				dbits = rbits6;
				sbits = lbits6;
			}
		} else {
			if (policy->family == AF_INET) {
				dbits = lbits4;
				sbits = rbits4;
			} else {
				dbits = lbits6;
				sbits = rbits6;
			}
		}

		if (policy->selector.prefixlen_d < dbits ||
		    policy->selector.prefixlen_s < sbits)
			continue;

		bin = xfrm_policy_inexact_alloc_bin(policy, dir);
		if (!bin)
			goto out_unlock;

		if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
			goto out_unlock;
	}

	/* reset the bydst and inexact table in all directions */
	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
		struct hlist_node *n;

		hlist_for_each_entry_safe(policy, n,
					  &net->xfrm.policy_inexact[dir],
					  bydst_inexact_list) {
			hlist_del_rcu(&policy->bydst);
			hlist_del_init(&policy->bydst_inexact_list);
		}

		hmask = net->xfrm.policy_bydst[dir].hmask;
		odst = net->xfrm.policy_bydst[dir].table;
		for (i = hmask; i >= 0; i--) {
			hlist_for_each_entry_safe(policy, n, odst + i, bydst)
				hlist_del_rcu(&policy->bydst);
		}
		if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
			/* dir out => dst = remote, src = local */
			net->xfrm.policy_bydst[dir].dbits4 = rbits4;
			net->xfrm.policy_bydst[dir].sbits4 = lbits4;
			net->xfrm.policy_bydst[dir].dbits6 = rbits6;
			net->xfrm.policy_bydst[dir].sbits6 = lbits6;
		} else {
			/* dir in/fwd => dst = local, src = remote */
			net->xfrm.policy_bydst[dir].dbits4 = lbits4;
			net->xfrm.policy_bydst[dir].sbits4 = rbits4;
			net->xfrm.policy_bydst[dir].dbits6 = lbits6;
			net->xfrm.policy_bydst[dir].sbits6 = rbits6;
		}
	}

	/* re-insert all policies by order of creation */
	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
		if (policy->walk.dead)
			continue;
		dir = xfrm_policy_id2dir(policy->index);
		if (dir >= XFRM_POLICY_MAX) {
			/* skip socket policies */
			continue;
		}
		newpos = NULL;
		chain = policy_hash_bysel(net, &policy->selector,
					  policy->family, dir);

		if (!chain) {
			void *p = xfrm_policy_inexact_insert(policy, dir, 0);

			WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
			continue;
		}

		hlist_for_each_entry(pol, chain, bydst) {
			if (policy->priority >= pol->priority)
				newpos = &pol->bydst;
			else
				break;
		}
		if (newpos)
			hlist_add_behind_rcu(&policy->bydst, newpos);
		else
			hlist_add_head_rcu(&policy->bydst, chain);
	}

out_unlock:
	__xfrm_policy_inexact_flush(net);
	write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);

	mutex_unlock(&hash_resize_mutex);
}


xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
		 u8 type, int dir, u32 id, int delete, int *err)
{
	struct xfrm_policy *pol, *ret;
	struct hlist_head *chain;

	*err = -ENOENT;
	if (xfrm_policy_id2dir(id) != dir)
		return NULL;

	*err = 0;
	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	chain = net->xfrm.policy_byidx + idx_hash(net, id);
	ret = NULL;
	hlist_for_each_entry(pol, chain, byidx) {
		if (pol->type == type && pol->index == id &&
		    pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
			xfrm_pol_hold(pol);
			if (delete) {
				*err = security_xfrm_policy_delete(
								pol->security);
				if (*err) {
					spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
					return pol;
				}
				__xfrm_policy_unlink(pol, dir);
			}
			ret = pol;
			break;
		}
	}
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);

	if (ret && delete)
		xfrm_policy_kill(ret);
	return ret;
}


xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
			       const struct flowi *fl, u16 family,
			       struct dst_entry *dst_orig)
{
	struct net *net = xp_net(pols[0]);
	struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
	struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
	struct xfrm_dst *xdst;
	struct dst_entry *dst;
	int err;

	/* Try to instantiate a bundle */
	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
	if (err <= 0) {
		if (err == 0)
			return NULL;

		if (err != -EAGAIN)
			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
		return ERR_PTR(err);
	}

	dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
	if (IS_ERR(dst)) {
		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
		return ERR_CAST(dst);
	}

	xdst = (struct xfrm_dst *)dst;
	xdst->num_xfrms = err;
	xdst->num_pols = num_pols;
	memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
	xdst->policy_genid = atomic_read(&pols[0]->genid);

	return xdst;
}


void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
{
	while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
		dst->dev = blackhole_netdev;
		dev_hold(dst->dev);
		dev_put(dev);
	}
}


static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
			    const void *ptr)
{
	const struct xfrm_pol_inexact_key *key = arg->key;
	const struct xfrm_pol_inexact_bin *b = ptr;
	int ret;

	if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
		return -1;

	ret = b->k.dir ^ key->dir;
	if (ret)
		return ret;

	ret = b->k.type ^ key->type;
	if (ret)
		return ret;

	ret = b->k.family ^ key->family;
	if (ret)
		return ret;

	return b->k.if_id ^ key->if_id;
}


__xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
			u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
			struct xfrm_sec_ctx *ctx)
{
	struct xfrm_policy *pol;

	if (!chain)
		return NULL;

	hlist_for_each_entry(pol, chain, bydst) {
		if (pol->type == type &&
		    pol->if_id == if_id &&
		    xfrm_policy_mark_match(mark, pol) &&
		    !selector_cmp(sel, &pol->selector) &&
		    xfrm_sec_ctx_match(ctx, pol->security))
			return pol;
	}

	return NULL;
}


xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
	       xfrm_address_t *remote, unsigned short family, u32 mark)
{
	int err;
	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);

	if (unlikely(afinfo == NULL))
		return -EINVAL;
	err = afinfo->get_saddr(net, oif, local, remote, mark);
	rcu_read_unlock();
	return err;
}


static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
					       int family, u8 prefixlen)
{
	if (xfrm_addr_any(addr, family))
		return true;

	if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
		return true;

	if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
		return true;

	return false;
}


int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
			  unsigned int family, int reverse)
{
	switch (family) {
	case AF_INET:
		decode_session4(skb, fl, reverse);
		break;
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
		decode_session6(skb, fl, reverse);
		break;
#endif
	default:
		return -EAFNOSUPPORT;
	}

	return security_xfrm_decode_session(skb, &fl->flowi_secid);
}


xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
{
	struct xfrm_policy *pol;
	int err = 0;

	list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
		if (pol->walk.dead ||
		    xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
		    pol->type != type)
			continue;

		err = security_xfrm_policy_delete(pol->security);
		if (err) {
			xfrm_audit_policy_delete(pol, 0, task_valid);
			return err;
		}
	}
	return err;
}


int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
{
	struct net *net = dev_net(skb->dev);
	struct flowi fl;
	struct dst_entry *dst;
	int res = 1;

	if (xfrm_decode_session(skb, &fl, family) < 0) {
		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
		return 0;
	}

	skb_dst_force(skb);
	if (!skb_dst(skb)) {
		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
		return 0;
	}

	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
	if (IS_ERR(dst)) {
		res = 0;
		dst = NULL;
	}
	skb_dst_set(skb, dst);
	return res;
}


static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
{
	struct net *net = read_pnet(&b->k.net);

	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	__xfrm_policy_inexact_prune_bin(b, false);
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
}


struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
					struct dst_entry *dst_orig,
					const struct flowi *fl,
					const struct sock *sk,
					int flags, u32 if_id)
{
	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
	struct xfrm_dst *xdst;
	struct dst_entry *dst, *route;
	u16 family = dst_orig->ops->family;
	u8 dir = XFRM_POLICY_OUT;
	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;

	dst = NULL;
	xdst = NULL;
	route = NULL;

	sk = sk_const_to_full_sk(sk);
	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
		num_pols = 1;
		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
						if_id);
		err = xfrm_expand_policies(fl, family, pols,
					   &num_pols, &num_xfrms);
		if (err < 0)
			goto dropdst;

		if (num_pols) {
			if (num_xfrms <= 0) {
				drop_pols = num_pols;
				goto no_transform;
			}

			xdst = xfrm_resolve_and_create_bundle(
					pols, num_pols, fl,
					family, dst_orig);

			if (IS_ERR(xdst)) {
				xfrm_pols_put(pols, num_pols);
				err = PTR_ERR(xdst);
				if (err == -EREMOTE)
					goto nopol;

				goto dropdst;
			} else if (xdst == NULL) {
				num_xfrms = 0;
				drop_pols = num_pols;
				goto no_transform;
			}

			route = xdst->route;
		}
	}

	if (xdst == NULL) {
		struct xfrm_flo xflo;

		xflo.dst_orig = dst_orig;
		xflo.flags = flags;

		/* To accelerate a bit...  */
		if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
			       !net->xfrm.policy_count[XFRM_POLICY_OUT]))
			goto nopol;

		xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
		if (xdst == NULL)
			goto nopol;
		if (IS_ERR(xdst)) {
			err = PTR_ERR(xdst);
			goto dropdst;
		}

		num_pols = xdst->num_pols;
		num_xfrms = xdst->num_xfrms;
		memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
		route = xdst->route;
	}

	dst = &xdst->u.dst;
	if (route == NULL && num_xfrms > 0) {
		/* The only case when xfrm_bundle_lookup() returns a
		 * bundle with null route, is when the template could
		 * not be resolved. It means policies are there, but
		 * bundle could not be created, since we don't yet
		 * have the xfrm_state's. We need to wait for KM to
		 * negotiate new SA's or bail out with error.*/
		if (net->xfrm.sysctl_larval_drop) {
			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
			err = -EREMOTE;
			goto error;
		}

		err = -EAGAIN;

		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
		goto error;
	}

no_transform:
	if (num_pols == 0)
		goto nopol;

	if ((flags & XFRM_LOOKUP_ICMP) &&
	    !(pols[0]->flags & XFRM_POLICY_ICMP)) {
		err = -ENOENT;
		goto error;
	}

	for (i = 0; i < num_pols; i++)
		pols[i]->curlft.use_time = ktime_get_real_seconds();

	if (num_xfrms < 0) {
		/* Prohibit the flow */
		XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
		err = -EPERM;
		goto error;
	} else if (num_xfrms > 0) {
		/* Flow transformed */
		dst_release(dst_orig);
	} else {
		/* Flow passes untransformed */
		dst_release(dst);
		dst = dst_orig;
	}
ok:
	xfrm_pols_put(pols, drop_pols);
	if (dst && dst->xfrm &&
	    dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
		dst->flags |= DST_XFRM_TUNNEL;
	return dst;

nopol:
	if (!(dst_orig->dev->flags & IFF_LOOPBACK) &&
	    net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
		err = -EPERM;
		goto error;
	}
	if (!(flags & XFRM_LOOKUP_ICMP)) {
		dst = dst_orig;
		goto ok;
	}
	err = -ENOENT;
error:
	dst_release(dst);
dropdst:
	if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
		dst_release(dst_orig);
	xfrm_pols_put(pols, drop_pols);
	return ERR_PTR(err);
}


static void __net_exit xfrm_net_exit(struct net *net)
{
	xfrm_sysctl_fini(net);
	xfrm_policy_fini(net);
	xfrm_state_fini(net);
	xfrm_statistics_fini(net);
}


static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
						     const struct flowi *fl,
						     u16 family, u8 dir,
						     u32 if_id)
{
	struct xfrm_pol_inexact_candidates cand;
	const xfrm_address_t *daddr, *saddr;
	struct xfrm_pol_inexact_bin *bin;
	struct xfrm_policy *pol, *ret;
	struct hlist_head *chain;
	unsigned int sequence;
	int err;

	daddr = xfrm_flowi_daddr(fl, family);
	saddr = xfrm_flowi_saddr(fl, family);
	if (unlikely(!daddr || !saddr))
		return NULL;

	rcu_read_lock();
 retry:
	do {
		sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
		chain = policy_hash_direct(net, daddr, saddr, family, dir);
	} while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));

	ret = NULL;
	hlist_for_each_entry_rcu(pol, chain, bydst) {
		err = xfrm_policy_match(pol, fl, type, family, dir, if_id);
		if (err) {
			if (err == -ESRCH)
				continue;
			else {
				ret = ERR_PTR(err);
				goto fail;
			}
		} else {
			ret = pol;
			break;
		}
	}
	bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
	if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
							 daddr))
		goto skip_inexact;

	pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
					  family, dir, if_id);
	if (pol) {
		ret = pol;
		if (IS_ERR(pol))
			goto fail;
	}

skip_inexact:
	if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
		goto retry;

	if (ret && !xfrm_pol_hold_rcu(ret))
		goto retry;
fail:
	rcu_read_unlock();

	return ret;
}


static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
					const void *daddr)
{
	while (dst->xfrm) {
		const struct xfrm_state *xfrm = dst->xfrm;

		dst = xfrm_dst_child(dst);

		if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
			continue;
		if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
			daddr = xfrm->coaddr;
		else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
			daddr = &xfrm->id.daddr;
	}
	return daddr;
}


static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
{
	const struct xfrm_pol_inexact_key *k = data;
	u32 a = k->type << 24 | k->dir << 16 | k->family;

	return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
			    seed);
}


static void xfrm_policy_fini(struct net *net)
{
	struct xfrm_pol_inexact_bin *b, *t;
	unsigned int sz;
	int dir;

	flush_work(&net->xfrm.policy_hash_work);
#ifdef CONFIG_XFRM_SUB_POLICY
	xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
#endif
	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);

	WARN_ON(!list_empty(&net->xfrm.policy_all));

	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
		struct xfrm_policy_hash *htab;

		WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));

		htab = &net->xfrm.policy_bydst[dir];
		sz = (htab->hmask + 1) * sizeof(struct hlist_head);
		WARN_ON(!hlist_empty(htab->table));
		xfrm_hash_free(htab->table, sz);
	}

	sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
	WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
	xfrm_hash_free(net->xfrm.policy_byidx, sz);

	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
		__xfrm_policy_inexact_prune_bin(b, true);
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
}


static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
					    struct xfrm_state **xfrm,
					    struct xfrm_dst **bundle,
					    int nx,
					    const struct flowi *fl,
					    struct dst_entry *dst)
{
	const struct xfrm_state_afinfo *afinfo;
	const struct xfrm_mode *inner_mode;
	struct net *net = xp_net(policy);
	unsigned long now = jiffies;
	struct net_device *dev;
	struct xfrm_dst *xdst_prev = NULL;
	struct xfrm_dst *xdst0 = NULL;
	int i = 0;
	int err;
	int header_len = 0;
	int nfheader_len = 0;
	int trailer_len = 0;
	int tos;
	int family = policy->selector.family;
	xfrm_address_t saddr, daddr;

	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);

	tos = xfrm_get_tos(fl, family);

	dst_hold(dst);

	for (; i < nx; i++) {
		struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
		struct dst_entry *dst1 = &xdst->u.dst;

		err = PTR_ERR(xdst);
		if (IS_ERR(xdst)) {
			dst_release(dst);
			goto put_states;
		}

		bundle[i] = xdst;
		if (!xdst_prev)
			xdst0 = xdst;
		else
			/* Ref count is taken during xfrm_alloc_dst()
			 * No need to do dst_clone() on dst1
			 */
			xfrm_dst_set_child(xdst_prev, &xdst->u.dst);

		if (xfrm[i]->sel.family == AF_UNSPEC) {
			inner_mode = xfrm_ip2inner_mode(xfrm[i],
							xfrm_af2proto(family));
			if (!inner_mode) {
				err = -EAFNOSUPPORT;
				dst_release(dst);
				goto put_states;
			}
		} else
			inner_mode = &xfrm[i]->inner_mode;

		xdst->route = dst;
		dst_copy_metrics(dst1, dst);

		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
			__u32 mark = 0;
			int oif;

			if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
				mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);

			family = xfrm[i]->props.family;
			oif = fl->flowi_oif ? : fl->flowi_l3mdev;
			dst = xfrm_dst_lookup(xfrm[i], tos, oif,
					      &saddr, &daddr, family, mark);
			err = PTR_ERR(dst);
			if (IS_ERR(dst))
				goto put_states;
		} else
			dst_hold(dst);

		dst1->xfrm = xfrm[i];
		xdst->xfrm_genid = xfrm[i]->genid;

		dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
		dst1->lastuse = now;

		dst1->input = dst_discard;

		rcu_read_lock();
		afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
		if (likely(afinfo))
			dst1->output = afinfo->output;
		else
			dst1->output = dst_discard_out;
		rcu_read_unlock();

		xdst_prev = xdst;

		header_len += xfrm[i]->props.header_len;
		if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
			nfheader_len += xfrm[i]->props.header_len;
		trailer_len += xfrm[i]->props.trailer_len;
	}

	xfrm_dst_set_child(xdst_prev, dst);
	xdst0->path = dst;

	err = -ENODEV;
	dev = dst->dev;
	if (!dev)
		goto free_dst;

	xfrm_init_path(xdst0, dst, nfheader_len);
	xfrm_init_pmtu(bundle, nx);

	for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
	     xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
		err = xfrm_fill_dst(xdst_prev, dev, fl);
		if (err)
			goto free_dst;

		xdst_prev->u.dst.header_len = header_len;
		xdst_prev->u.dst.trailer_len = trailer_len;
		header_len -= xdst_prev->u.dst.xfrm->props.header_len;
		trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
	}

	return &xdst0->u.dst;

put_states:
	for (; i < nx; i++)
		xfrm_state_put(xfrm[i]);
free_dst:
	if (xdst0)
		dst_release_immediate(&xdst0->u.dst);

	return ERR_PTR(err);
}


static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
						 struct xfrm_flo *xflo,
						 const struct flowi *fl,
						 int num_xfrms,
						 u16 family)
{
	int err;
	struct net_device *dev;
	struct dst_entry *dst;
	struct dst_entry *dst1;
	struct xfrm_dst *xdst;

	xdst = xfrm_alloc_dst(net, family);
	if (IS_ERR(xdst))
		return xdst;

	if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
	    net->xfrm.sysctl_larval_drop ||
	    num_xfrms <= 0)
		return xdst;

	dst = xflo->dst_orig;
	dst1 = &xdst->u.dst;
	dst_hold(dst);
	xdst->route = dst;

	dst_copy_metrics(dst1, dst);

	dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
	dst1->flags |= DST_XFRM_QUEUE;
	dst1->lastuse = jiffies;

	dst1->input = dst_discard;
	dst1->output = xdst_queue_output;

	dst_hold(dst);
	xfrm_dst_set_child(xdst, dst);
	xdst->path = dst;

	xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);

	err = -ENODEV;
	dev = dst->dev;
	if (!dev)
		goto free_dst;

	err = xfrm_fill_dst(xdst, dev, fl);
	if (err)
		goto free_dst;

out:
	return xdst;

free_dst:
	dst_release(dst1);
	xdst = ERR_PTR(err);
	goto out;
}


xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
				struct xfrm_policy *policy, u8 dir)
{
	struct xfrm_pol_inexact_node *n;
	struct net *net;

	net = xp_net(policy);
	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);

	if (xfrm_policy_inexact_insert_use_any_list(policy))
		return &bin->hhead;

	if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
					       policy->family,
					       policy->selector.prefixlen_d)) {
		write_seqcount_begin(&bin->count);
		n = xfrm_policy_inexact_insert_node(net,
						    &bin->root_s,
						    &policy->selector.saddr,
						    policy->family,
						    policy->selector.prefixlen_s,
						    dir);
		write_seqcount_end(&bin->count);
		if (!n)
			return NULL;

		return &n->hhead;
	}

	/* daddr is fixed */
	write_seqcount_begin(&bin->count);
	n = xfrm_policy_inexact_insert_node(net,
					    &bin->root_d,
					    &policy->selector.daddr,
					    policy->family,
					    policy->selector.prefixlen_d, dir);
	write_seqcount_end(&bin->count);
	if (!n)
		return NULL;

	/* saddr is wildcard */
	if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
					       policy->family,
					       policy->selector.prefixlen_s))
		return &n->hhead;

	write_seqcount_begin(&bin->count);
	n = xfrm_policy_inexact_insert_node(net,
					    &n->root,
					    &policy->selector.saddr,
					    policy->family,
					    policy->selector.prefixlen_s, dir);
	write_seqcount_end(&bin->count);
	if (!n)
		return NULL;

	return &n->hhead;
}


static void xfrm_policy_insert_inexact_list(struct hlist_head *chain,
					    struct xfrm_policy *policy)
{
	struct xfrm_policy *pol, *delpol = NULL;
	struct hlist_node *newpos = NULL;
	int i = 0;

	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
		if (pol->type == policy->type &&
		    pol->if_id == policy->if_id &&
		    !selector_cmp(&pol->selector, &policy->selector) &&
		    xfrm_policy_mark_match(&policy->mark, pol) &&
		    xfrm_sec_ctx_match(pol->security, policy->security) &&
		    !WARN_ON(delpol)) {
			delpol = pol;
			if (policy->priority > pol->priority)
				continue;
		} else if (policy->priority >= pol->priority) {
			newpos = &pol->bydst_inexact_list;
			continue;
		}
		if (delpol)
			break;
	}

	if (newpos)
		hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos);
	else
		hlist_add_head_rcu(&policy->bydst_inexact_list, chain);

	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
		pol->pos = i;
		i++;
	}
}


int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
		 struct xfrm_migrate *m, int num_migrate,
		 struct xfrm_kmaddress *k, struct net *net,
		 struct xfrm_encap_tmpl *encap, u32 if_id)
{
	int i, err, nx_cur = 0, nx_new = 0;
	struct xfrm_policy *pol = NULL;
	struct xfrm_state *x, *xc;
	struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
	struct xfrm_state *x_new[XFRM_MAX_DEPTH];
	struct xfrm_migrate *mp;

	/* Stage 0 - sanity checks */
	if ((err = xfrm_migrate_check(m, num_migrate)) < 0)
		goto out;

	if (dir >= XFRM_POLICY_MAX) {
		err = -EINVAL;
		goto out;
	}

	/* Stage 1 - find policy */
	if ((pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id)) == NULL) {
		err = -ENOENT;
		goto out;
	}

	/* Stage 2 - find and update state(s) */
	for (i = 0, mp = m; i < num_migrate; i++, mp++) {
		if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
			x_cur[nx_cur] = x;
			nx_cur++;
			xc = xfrm_state_migrate(x, mp, encap);
			if (xc) {
				x_new[nx_new] = xc;
				nx_new++;
			} else {
				err = -ENODATA;
				goto restore_state;
			}
		}
	}

	/* Stage 3 - update policy */
	if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 0)
		goto restore_state;

	/* Stage 4 - delete old state(s) */
	if (nx_cur) {
		xfrm_states_put(x_cur, nx_cur);
		xfrm_states_delete(x_cur, nx_cur);
	}

	/* Stage 5 - announce */
	km_migrate(sel, dir, type, m, num_migrate, k, encap);

	xfrm_pol_put(pol);

	return 0;
out:
	return err;

restore_state:
	if (pol)
		xfrm_pol_put(pol);
	if (nx_cur)
		xfrm_states_put(x_cur, nx_cur);
	if (nx_new)
		xfrm_states_delete(x_new, nx_new);

	return err;
}


static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
{
	return dst_metric_advmss(xfrm_dst_path(dst));
}


static void xfrm_bydst_resize(struct net *net, int dir)
{
	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
	unsigned int nhashmask = xfrm_new_hash_mask(hmask);
	unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
	struct hlist_head *ndst = xfrm_hash_alloc(nsize);
	struct hlist_head *odst;
	int i;

	if (!ndst)
		return;

	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);

	odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
				lockdep_is_held(&net->xfrm.xfrm_policy_lock));

	for (i = hmask; i >= 0; i--)
		xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);

	rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
	net->xfrm.policy_bydst[dir].hmask = nhashmask;

	write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);

	synchronize_rcu();

	xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
}


static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
{
	write_seqcount_begin(&b->count);
	xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
	xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
	write_seqcount_end(&b->count);

	if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
	    !hlist_empty(&b->hhead)) {
		WARN_ON_ONCE(net_exit);
		return;
	}

	if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
				   xfrm_pol_inexact_params) == 0) {
		list_del(&b->inexact_bins);
		kfree_rcu(b, rcu);
	}
}


static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
						    u8 dir, u8 type, struct net *net, u32 if_id)
{
	struct xfrm_policy *pol, *ret = NULL;
	struct hlist_head *chain;
	u32 priority = ~0U;

	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
	hlist_for_each_entry(pol, chain, bydst) {
		if ((if_id == 0 || pol->if_id == if_id) &&
		    xfrm_migrate_selector_match(sel, &pol->selector) &&
		    pol->type == type) {
			ret = pol;
			priority = ret->priority;
			break;
		}
	}
	chain = &net->xfrm.policy_inexact[dir];
	hlist_for_each_entry(pol, chain, bydst_inexact_list) {
		if ((pol->priority >= priority) && ret)
			break;

		if ((if_id == 0 || pol->if_id == if_id) &&
		    xfrm_migrate_selector_match(sel, &pol->selector) &&
		    pol->type == type) {
			ret = pol;
			break;
		}
	}

	xfrm_pol_hold(ret);

	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);

	return ret;
}


static int xfrm_policy_addr_delta(const xfrm_address_t *a,
				  const xfrm_address_t *b,
				  u8 prefixlen, u16 family)
{
	u32 ma, mb, mask;
	unsigned int pdw, pbi;
	int delta = 0;

	switch (family) {
	case AF_INET:
		if (prefixlen == 0)
			return 0;
		mask = ~0U << (32 - prefixlen);
		ma = ntohl(a->a4) & mask;
		mb = ntohl(b->a4) & mask;
		if (ma < mb)
			delta = -1;
		else if (ma > mb)
			delta = 1;
		break;
	case AF_INET6:
		pdw = prefixlen >> 5;
		pbi = prefixlen & 0x1f;

		if (pdw) {
			delta = memcmp(a->a6, b->a6, pdw << 2);
			if (delta)
				return delta;
		}
		if (pbi) {
			mask = ~0U << (32 - pbi);
			ma = ntohl(a->a6[pdw]) & mask;
			mb = ntohl(b->a6[pdw]) & mask;
			if (ma < mb)
				delta = -1;
			else if (ma > mb)
				delta = 1;
		}
		break;
	default:
		break;
	}

	return delta;
}


static void __xfrm_policy_inexact_flush(struct net *net)
{
	struct xfrm_pol_inexact_bin *bin, *t;

	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);

	list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
		__xfrm_policy_inexact_prune_bin(bin, false);
}


static void xfrm_policy_inexact_list_reinsert(struct net *net,
					      struct xfrm_pol_inexact_node *n,
					      u16 family)
{
	unsigned int matched_s, matched_d;
	struct xfrm_policy *policy, *p;

	matched_s = 0;
	matched_d = 0;

	list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
		struct hlist_node *newpos = NULL;
		bool matches_s, matches_d;

		if (!policy->bydst_reinsert)
			continue;

		WARN_ON_ONCE(policy->family != family);

		policy->bydst_reinsert = false;
		hlist_for_each_entry(p, &n->hhead, bydst) {
			if (policy->priority > p->priority)
				newpos = &p->bydst;
			else if (policy->priority == p->priority &&
				 policy->pos > p->pos)
				newpos = &p->bydst;
			else
				break;
		}

		if (newpos)
			hlist_add_behind_rcu(&policy->bydst, newpos);
		else
			hlist_add_head_rcu(&policy->bydst, &n->hhead);

		/* paranoia checks follow.
		 * Check that the reinserted policy matches at least
		 * saddr or daddr for current node prefix.
		 *
		 * Matching both is fine, matching saddr in one policy
		 * (but not daddr) and then matching only daddr in another
		 * is a bug.
		 */
		matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
						   &n->addr,
						   n->prefixlen,
						   family) == 0;
		matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
						   &n->addr,
						   n->prefixlen,
						   family) == 0;
		if (matches_s && matches_d)
			continue;

		WARN_ON_ONCE(!matches_s && !matches_d);
		if (matches_s)
			matched_s++;
		if (matches_d)
			matched_d++;
		WARN_ON_ONCE(matched_s && matched_d);
	}
}


static void xfrm_policy_timer(struct timer_list *t)
{
	struct xfrm_policy *xp = from_timer(xp, t, timer);
	time64_t now = ktime_get_real_seconds();
	time64_t next = TIME64_MAX;
	int warn = 0;
	int dir;

	read_lock(&xp->lock);

	if (unlikely(xp->walk.dead))
		goto out;

	dir = xfrm_policy_id2dir(xp->index);

	if (xp->lft.hard_add_expires_seconds) {
		time64_t tmo = xp->lft.hard_add_expires_seconds +
			xp->curlft.add_time - now;
		if (tmo <= 0)
			goto expired;
		if (tmo < next)
			next = tmo;
	}
	if (xp->lft.hard_use_expires_seconds) {
		time64_t tmo = xp->lft.hard_use_expires_seconds +
			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
		if (tmo <= 0)
			goto expired;
		if (tmo < next)
			next = tmo;
	}
	if (xp->lft.soft_add_expires_seconds) {
		time64_t tmo = xp->lft.soft_add_expires_seconds +
			xp->curlft.add_time - now;
		if (tmo <= 0) {
			warn = 1;
			tmo = XFRM_KM_TIMEOUT;
		}
		if (tmo < next)
			next = tmo;
	}
	if (xp->lft.soft_use_expires_seconds) {
		time64_t tmo = xp->lft.soft_use_expires_seconds +
			(xp->curlft.use_time ? : xp->curlft.add_time) - now;
		if (tmo <= 0) {
			warn = 1;
			tmo = XFRM_KM_TIMEOUT;
		}
		if (tmo < next)
			next = tmo;
	}

	if (warn)
		km_policy_expired(xp, dir, 0, 0);
	if (next != TIME64_MAX &&
	    !mod_timer(&xp->timer, jiffies + make_jiffies(next)))
		xfrm_pol_hold(xp);

out:
	read_unlock(&xp->lock);
	xfrm_pol_put(xp);
	return;

expired:
	read_unlock(&xp->lock);
	if (!xfrm_policy_delete(xp, dir))
		km_policy_expired(xp, dir, 1, 0);
	xfrm_pol_put(xp);
}


static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
{
	const struct xfrm_pol_inexact_bin *b = data;

	return xfrm_pol_bin_key(&b->k, 0, seed);
}


xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
{
	struct sec_path *sp = skb_sec_path(skb);
	struct xfrm_state *x;

	if (!sp || idx < 0 || idx >= sp->len)
		return 0;
	x = sp->xvec[idx];
	if (!x->type->reject)
		return 0;
	return x->type->reject(x, skb, fl);
}


static void xfrm_policy_inexact_node_reinsert(struct net *net,
					      struct xfrm_pol_inexact_node *n,
					      struct rb_root *new,
					      u16 family)
{
	struct xfrm_pol_inexact_node *node;
	struct rb_node **p, *parent;

	/* we should not have another subtree here */
	WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
restart:
	parent = NULL;
	p = &new->rb_node;
	while (*p) {
		u8 prefixlen;
		int delta;

		parent = *p;
		node = rb_entry(*p, struct xfrm_pol_inexact_node, node);

		prefixlen = min(node->prefixlen, n->prefixlen);

		delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
					       prefixlen, family);
		if (delta < 0) {
			p = &parent->rb_left;
		} else if (delta > 0) {
			p = &parent->rb_right;
		} else {
			bool same_prefixlen = node->prefixlen == n->prefixlen;
			struct xfrm_policy *tmp;

			hlist_for_each_entry(tmp, &n->hhead, bydst) {
				tmp->bydst_reinsert = true;
				hlist_del_rcu(&tmp->bydst);
			}

			node->prefixlen = prefixlen;

			xfrm_policy_inexact_list_reinsert(net, node, family);

			if (same_prefixlen) {
				kfree_rcu(n, rcu);
				return;
			}

			rb_erase(*p, new);
			kfree_rcu(n, rcu);
			n = node;
			goto restart;
		}
	}

	rb_link_node_rcu(&n->node, parent, p);
	rb_insert_color(&n->node, new);
}


static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
{
	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
	struct net *net = xp_net(old);

	if (newp) {
		newp->selector = old->selector;
		if (security_xfrm_policy_clone(old->security,
					       &newp->security)) {
			kfree(newp);
			return NULL;  /* ENOMEM */
		}
		newp->lft = old->lft;
		newp->curlft = old->curlft;
		newp->mark = old->mark;
		newp->if_id = old->if_id;
		newp->action = old->action;
		newp->flags = old->flags;
		newp->xfrm_nr = old->xfrm_nr;
		newp->index = old->index;
		newp->type = old->type;
		newp->family = old->family;
		memcpy(newp->xfrm_vec, old->xfrm_vec,
		       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
		spin_lock_bh(&net->xfrm.xfrm_policy_lock);
		xfrm_sk_policy_link(newp, dir);
		spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
		xfrm_pol_put(newp);
	}
	return newp;
}


xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
			    struct xfrm_policy *prefer,
			    const struct flowi *fl,
			    u8 type, u16 family, int dir, u32 if_id)
{
	struct xfrm_policy *tmp;
	int i;

	for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
		tmp = __xfrm_policy_eval_candidates(cand->res[i],
						    prefer,
						    fl, type, family, dir,
						    if_id);
		if (!tmp)
			continue;

		if (IS_ERR(tmp))
			return tmp;
		prefer = tmp;
	}

	return prefer;
}


static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
{
	/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
	 * to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
	 * get validated by dst_ops->check on every use.  We do this
	 * because when a normal route referenced by an XFRM dst is
	 * obsoleted we do not go looking around for all parent
	 * referencing XFRM dsts so that we can invalidate them.  It
	 * is just too much work.  Instead we make the checks here on
	 * every use.  For example:
	 *
	 *	XFRM dst A --> IPv4 dst X
	 *
	 * X is the "xdst->route" of A (X is also the "dst->path" of A
	 * in this example).  If X is marked obsolete, "A" will not
	 * notice.  That's what we are validating here via the
	 * stale_bundle() check.
	 *
	 * When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
	 * be marked on it.
	 * This will force stale_bundle() to fail on any xdst bundle with
	 * this dst linked in it.
	 */
	if (dst->obsolete < 0 && !stale_bundle(dst))
		return dst;

	return NULL;
}


static void xfrm_policy_inexact_node_merge(struct net *net,
					   struct xfrm_pol_inexact_node *v,
					   struct xfrm_pol_inexact_node *n,
					   u16 family)
{
	struct xfrm_pol_inexact_node *node;
	struct xfrm_policy *tmp;
	struct rb_node *rnode;

	/* To-be-merged node v has a subtree.
	 *
	 * Dismantle it and insert its nodes to n->root.
	 */
	while ((rnode = rb_first(&v->root)) != NULL) {
		node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
		rb_erase(&node->node, &v->root);
		xfrm_policy_inexact_node_reinsert(net, node, &n->root,
						  family);
	}

	hlist_for_each_entry(tmp, &v->hhead, bydst) {
		tmp->bydst_reinsert = true;
		hlist_del_rcu(&tmp->bydst);
	}

	xfrm_policy_inexact_list_reinsert(net, n, family);
}


xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
{
	struct xfrm_pol_inexact_node *node;

	node = kzalloc(sizeof(*node), GFP_ATOMIC);
	if (node)
		xfrm_pol_inexact_node_init(node, addr, prefixlen);

	return node;
}


static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
{
	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
	struct dst_ops *dst_ops;
	struct xfrm_dst *xdst;

	if (!afinfo)
		return ERR_PTR(-EINVAL);

	switch (family) {
	case AF_INET:
		dst_ops = &net->xfrm.xfrm4_dst_ops;
		break;
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
		dst_ops = &net->xfrm.xfrm6_dst_ops;
		break;
#endif
	default:
		BUG();
	}
	xdst = dst_alloc(dst_ops, NULL, 1, DST_OBSOLETE_NONE, 0);

	if (likely(xdst)) {
		memset_after(xdst, 0, u.dst);
	} else
		xdst = ERR_PTR(-ENOBUFS);

	rcu_read_unlock();

	return xdst;
}


static int xfrm_policy_match(const struct xfrm_policy *pol,
			     const struct flowi *fl,
			     u8 type, u16 family, int dir, u32 if_id)
{
	const struct xfrm_selector *sel = &pol->selector;
	int ret = -ESRCH;
	bool match;

	if (pol->family != family ||
	    pol->if_id != if_id ||
	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
	    pol->type != type)
		return ret;

	match = xfrm_selector_match(sel, fl, family);
	if (match)
		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
	return ret;
}


int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
			unsigned short family)
{
	struct net *net = dev_net(skb->dev);
	struct xfrm_policy *pol;
	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
	int npols = 0;
	int xfrm_nr;
	int pi;
	int reverse;
	struct flowi fl;
	int xerr_idx = -1;
	const struct xfrm_if_cb *ifcb;
	struct sec_path *sp;
	struct xfrm_if *xi;
	u32 if_id = 0;

	rcu_read_lock();
	ifcb = xfrm_if_get_cb();

	if (ifcb) {
		xi = ifcb->decode_session(skb, family);
		if (xi) {
			if_id = xi->p.if_id;
			net = xi->net;
		}
	}
	rcu_read_unlock();

	reverse = dir & ~XFRM_POLICY_MASK;
	dir &= XFRM_POLICY_MASK;

	if (__xfrm_decode_session(skb, &fl, family, reverse) < 0) {
		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
		return 0;
	}

	nf_nat_decode_session(skb, &fl, family);

	/* First, check used SA against their selectors. */
	sp = skb_sec_path(skb);
	if (sp) {
		int i;

		for (i = sp->len - 1; i >= 0; i--) {
			struct xfrm_state *x = sp->xvec[i];
			if (!xfrm_selector_match(&x->sel, &fl, family)) {
				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
				return 0;
			}
		}
	}

	pol = NULL;
	sk = sk_to_full_sk(sk);
	if (sk && sk->sk_policy[dir]) {
		pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
		if (IS_ERR(pol)) {
			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
			return 0;
		}
	}

	if (!pol)
		pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);

	if (IS_ERR(pol)) {
		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
		return 0;
	}

	if (!pol) {
		if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
			return 0;
		}

		if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
			xfrm_secpath_reject(xerr_idx, skb, &fl);
			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
			return 0;
		}
		return 1;
	}

	pol->curlft.use_time = ktime_get_real_seconds();

	pols[0] = pol;
	npols++;
#ifdef CONFIG_XFRM_SUB_POLICY
	if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
		pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
						    &fl, family,
						    XFRM_POLICY_IN, if_id);
		if (pols[1]) {
			if (IS_ERR(pols[1])) {
				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
				return 0;
			}
			pols[1]->curlft.use_time = ktime_get_real_seconds();
			npols++;
		}
	}
#endif

	if (pol->action == XFRM_POLICY_ALLOW) {
		static struct sec_path dummy;
		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
		struct xfrm_tmpl **tpp = tp;
		int ti = 0;
		int i, k;

		sp = skb_sec_path(skb);
		if (!sp)
			sp = &dummy;

		for (pi = 0; pi < npols; pi++) {
			if (pols[pi] != pol &&
			    pols[pi]->action != XFRM_POLICY_ALLOW) {
				XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
				goto reject;
			}
			if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
				goto reject_error;
			}
			for (i = 0; i < pols[pi]->xfrm_nr; i++)
				tpp[ti++] = &pols[pi]->xfrm_vec[i];
		}
		xfrm_nr = ti;

		if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK &&
		    !xfrm_nr) {
			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
			goto reject;
		}

		if (npols > 1) {
			xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
			tpp = stp;
		}

		/* For each tunnel xfrm, find the first matching tmpl.
		 * For each tmpl before that, find corresponding xfrm.
		 * Order is _important_. Later we will implement
		 * some barriers, but at the moment barriers
		 * are implied between each two transformations.
		 */
		for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
			k = xfrm_policy_ok(tpp[i], sp, k, family);
			if (k < 0) {
				if (k < -1)
					/* "-2 - errored_index" returned */
					xerr_idx = -(2+k);
				XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
				goto reject;
			}
		}

		if (secpath_has_nontransport(sp, k, &xerr_idx)) {
			XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
			goto reject;
		}

		xfrm_pols_put(pols, npols);
		return 1;
	}
	XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);

reject:
	xfrm_secpath_reject(xerr_idx, skb, &fl);
reject_error:
	xfrm_pols_put(pols, npols);
	return 0;
}


xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
{
	struct xfrm_pol_inexact_bin *bin;
	struct xfrm_policy *delpol;
	struct hlist_head *chain;
	struct net *net;

	bin = xfrm_policy_inexact_alloc_bin(policy, dir);
	if (!bin)
		return ERR_PTR(-ENOMEM);

	net = xp_net(policy);
	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);

	chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
	if (!chain) {
		__xfrm_policy_inexact_prune_bin(bin, false);
		return ERR_PTR(-ENOMEM);
	}

	delpol = xfrm_policy_insert_list(chain, policy, excl);
	if (delpol && excl) {
		__xfrm_policy_inexact_prune_bin(bin, false);
		return ERR_PTR(-EEXIST);
	}

	chain = &net->xfrm.policy_inexact[dir];
	xfrm_policy_insert_inexact_list(chain, policy);

	if (delpol)
		__xfrm_policy_inexact_prune_bin(bin, false);

	return delpol;
}


xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
			       u8 dir, u32 if_id)
{
	struct xfrm_pol_inexact_key k = {
		.family = family,
		.type = type,
		.dir = dir,
		.if_id = if_id,
	};

	write_pnet(&k.net, net);

	return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
				 xfrm_pol_inexact_params);
}


xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
			   u8 dir, u32 if_id)
{
	struct xfrm_pol_inexact_bin *bin;

	lockdep_assert_held(&net->xfrm.xfrm_policy_lock);

	rcu_read_lock();
	bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
	rcu_read_unlock();

	return bin;
}


xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
				seqcount_spinlock_t *count,
				const xfrm_address_t *addr, u16 family)
{
	const struct rb_node *parent;
	int seq;

again:
	seq = read_seqcount_begin(count);

	parent = rcu_dereference_raw(r->rb_node);
	while (parent) {
		struct xfrm_pol_inexact_node *node;
		int delta;

		node = rb_entry(parent, struct xfrm_pol_inexact_node, node);

		delta = xfrm_policy_addr_delta(addr, &node->addr,
					       node->prefixlen, family);
		if (delta < 0) {
			parent = rcu_dereference_raw(parent->rb_left);
			continue;
		} else if (delta > 0) {
			parent = rcu_dereference_raw(parent->rb_right);
			continue;
		}

		return node;
	}

	if (read_seqcount_retry(count, seq))
		goto again;

	return NULL;
}


xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
		      u8 type, int dir, struct xfrm_selector *sel,
		      struct xfrm_sec_ctx *ctx, int delete, int *err)
{
	struct xfrm_pol_inexact_bin *bin = NULL;
	struct xfrm_policy *pol, *ret = NULL;
	struct hlist_head *chain;

	*err = 0;
	spin_lock_bh(&net->xfrm.xfrm_policy_lock);
	chain = policy_hash_bysel(net, sel, sel->family, dir);
	if (!chain) {
		struct xfrm_pol_inexact_candidates cand;
		int i;

		bin = xfrm_policy_inexact_lookup(net, type,
						 sel->family, dir, if_id);
		if (!bin) {
			spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
			return NULL;
		}

		if (!xfrm_policy_find_inexact_candidates(&cand, bin,
							 &sel->saddr,
							 &sel->daddr)) {
			spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
			return NULL;
		}

		pol = NULL;
		for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
			struct xfrm_policy *tmp;

			tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
						      if_id, type, dir,
						      sel, ctx);
			if (!tmp)
				continue;

			if (!pol || tmp->pos < pol->pos)
				pol = tmp;
		}
	} else {
		pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
					      sel, ctx);
	}

	if (pol) {
		xfrm_pol_hold(pol);
		if (delete) {
			*err = security_xfrm_policy_delete(pol->security);
			if (*err) {
				spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
				return pol;
			}
			__xfrm_policy_unlink(pol, dir);
		}
		ret = pol;
	}
	spin_unlock_bh(&net->xfrm.xfrm_policy_lock);

	if (ret && delete)
		xfrm_policy_kill(ret);
	if (bin && delete)
		xfrm_policy_inexact_prune_bin(bin);
	return ret;
}


static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
					   struct sk_buff *skb,
					   const void *daddr)
{
	const struct dst_entry *path = xfrm_dst_path(dst);

	if (!skb)
		daddr = xfrm_get_dst_nexthop(dst, daddr);
	return path->ops->neigh_lookup(path, skb, daddr);
}


static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
{
	while (nr--) {
		struct xfrm_dst *xdst = bundle[nr];
		u32 pmtu, route_mtu_cached;
		struct dst_entry *dst;

		dst = &xdst->u.dst;
		pmtu = dst_mtu(xfrm_dst_child(dst));
		xdst->child_mtu_cached = pmtu;

		pmtu = xfrm_state_mtu(dst->xfrm, pmtu);

		route_mtu_cached = dst_mtu(xdst->route);
		xdst->route_mtu_cached = route_mtu_cached;

		if (pmtu > route_mtu_cached)
			pmtu = route_mtu_cached;

		dst_metric_set(dst, RTAX_MTU, pmtu);
	}
}


static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
						   struct xfrm_policy *policy,
						   bool excl)
{
	struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;

	hlist_for_each_entry(pol, chain, bydst) {
		if (pol->type == policy->type &&
		    pol->if_id == policy->if_id &&
		    !selector_cmp(&pol->selector, &policy->selector) &&
		    xfrm_policy_mark_match(&policy->mark, pol) &&
		    xfrm_sec_ctx_match(pol->security, policy->security) &&
		    !WARN_ON(delpol)) {
			if (excl)
				return ERR_PTR(-EEXIST);
			delpol = pol;
			if (policy->priority > pol->priority)
				continue;
		} else if (policy->priority >= pol->priority) {
			newpos = pol;
			continue;
		}
		if (delpol)
			break;
	}

	if (newpos)
		hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
	else
		hlist_add_head_rcu(&policy->bydst, chain);

	return delpol;
}


static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
				       const xfrm_address_t *addr, u8 prefixlen)
{
	node->addr = *addr;
	node->prefixlen = prefixlen;
}


static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
						int dir)
{
	struct net *net = xp_net(pol);

	if (list_empty(&pol->walk.all))
		return NULL;

	/* Socket policies are not hashed. */
	if (!hlist_unhashed(&pol->bydst)) {
		hlist_del_rcu(&pol->bydst);
		hlist_del_init(&pol->bydst_inexact_list);
		hlist_del(&pol->byidx);
	}

	list_del_init(&pol->walk.all);
	net->xfrm.policy_count[dir]--;

	return pol;
}


static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
					  struct xfrm_policy *pol)
{
	return mark->v == pol->mark.v && mark->m == pol->mark.m;
}


static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
						 const struct flowi *fl,
						 u16 family, u32 if_id)
{
	struct xfrm_policy *pol;

	rcu_read_lock();
 again:
	pol = rcu_dereference(sk->sk_policy[dir]);
	if (pol != NULL) {
		bool match;
		int err = 0;

		if (pol->family != family) {
			pol = NULL;
			goto out;
		}

		match = xfrm_selector_match(&pol->selector, fl, family);
		if (match) {
			if ((sk->sk_mark & pol->mark.m) != pol->mark.v ||
			    pol->if_id != if_id) {
				pol = NULL;
				goto out;
			}
			err = security_xfrm_policy_lookup(pol->security,
						      fl->flowi_secid);
			if (!err) {
				if (!xfrm_pol_hold_rcu(pol))
					goto again;
			} else if (err == -ESRCH) {
				pol = NULL;
			} else {
				pol = ERR_PTR(err);
			}
		} else
			pol = NULL;
	}
out:
	rcu_read_unlock();
	return pol;
}


static bool get_bool(struct platform_device *ofdev, const char *s)
{
	u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);

	if (!p) {
		dev_warn(&ofdev->dev, "Parameter %s not found, defaulting to false\n", s);
		return false;
	}

	return (bool)*p;
}

net: xilinx_emaclite: Do not print real IOMEM pointer

Printing kernel pointers is discouraged because they might leak kernel
memory layout.  This fixes smatch warning:

drivers/net/ethernet/xilinx/xilinx_emaclite.c:1191 xemaclite_of_probe() warn:
 argument 4 to %08lX specifier is cast from pointer

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>


static void xemaclite_aligned_write(void *src_ptr, u32 *dest_ptr,
				    unsigned length)
{
	u32 align_buffer;
	u32 *to_u32_ptr;
	u16 *from_u16_ptr, *to_u16_ptr;

	to_u32_ptr = dest_ptr;
	from_u16_ptr = src_ptr;
	align_buffer = 0;

	for (; length > 3; length -= 4) {
		to_u16_ptr = (u16 *)&align_buffer;
		*to_u16_ptr++ = *from_u16_ptr++;
		*to_u16_ptr++ = *from_u16_ptr++;

		/* This barrier resolves occasional issues seen around
		 * cases where the data is not properly flushed out
		 * from the processor store buffers to the destination
		 * memory locations.
		 */
		wmb();

		/* Output a word */
		*to_u32_ptr++ = align_buffer;
	}
	if (length) {
		u8 *from_u8_ptr, *to_u8_ptr;

		/* Set up to output the remaining data */
		align_buffer = 0;
		to_u8_ptr = (u8 *)&align_buffer;
		from_u8_ptr = (u8 *)from_u16_ptr;

		/* Output the remaining data */
		for (; length > 0; length--)
			*to_u8_ptr++ = *from_u8_ptr++;

		/* This barrier resolves occasional issues seen around
		 * cases where the data is not properly flushed out
		 * from the processor store buffers to the destination
		 * memory locations.
		 */
		wmb();
		*to_u32_ptr = align_buffer;
	}
}


static void xemaclite_aligned_read(u32 *src_ptr, u8 *dest_ptr,
				   unsigned length)
{
	u16 *to_u16_ptr, *from_u16_ptr;
	u32 *from_u32_ptr;
	u32 align_buffer;

	from_u32_ptr = src_ptr;
	to_u16_ptr = (u16 *)dest_ptr;

	for (; length > 3; length -= 4) {
		/* Copy each word into the temporary buffer */
		align_buffer = *from_u32_ptr++;
		from_u16_ptr = (u16 *)&align_buffer;

		/* Read data from source */
		*to_u16_ptr++ = *from_u16_ptr++;
		*to_u16_ptr++ = *from_u16_ptr++;
	}

	if (length) {
		u8 *to_u8_ptr, *from_u8_ptr;

		/* Set up to read the remaining data */
		to_u8_ptr = (u8 *)to_u16_ptr;
		align_buffer = *from_u32_ptr++;
		from_u8_ptr = (u8 *)&align_buffer;

		/* Read the remaining data */
		for (; length > 0; length--)
			*to_u8_ptr = *from_u8_ptr;
	}
}


static void xemaclite_ethtools_get_drvinfo(struct net_device *ndev,
					   struct ethtool_drvinfo *ed)
{
	strlcpy(ed->driver, DRIVER_NAME, sizeof(ed->driver));
}


static void xemaclite_rx_handler(struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);
	struct sk_buff *skb;
	unsigned int align;
	u32 len;

	len = ETH_FRAME_LEN + ETH_FCS_LEN;
	skb = netdev_alloc_skb(dev, len + ALIGNMENT);
	if (!skb) {
		/* Couldn't get memory. */
		dev->stats.rx_dropped++;
		dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
		return;
	}

	/* A new skb should have the data halfword aligned, but this code is
	 * here just in case that isn't true. Calculate how many
	 * bytes we should reserve to get the data to start on a word
	 * boundary
	 */
	align = BUFFER_ALIGN(skb->data);
	if (align)
		skb_reserve(skb, align);

	skb_reserve(skb, 2);

	len = xemaclite_recv_data(lp, (u8 *)skb->data, len);

	if (!len) {
		dev->stats.rx_errors++;
		dev_kfree_skb_irq(skb);
		return;
	}

	skb_put(skb, len);	/* Tell the skb how much data we got */

	skb->protocol = eth_type_trans(skb, dev);
	skb_checksum_none_assert(skb);

	dev->stats.rx_packets++;
	dev->stats.rx_bytes += len;

	if (!skb_defer_rx_timestamp(skb))
		netif_rx(skb);	/* Send the packet upstream */
}


static void xemaclite_tx_handler(struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);

	dev->stats.tx_packets++;

	if (!lp->deferred_skb)
		return;

	if (xemaclite_send_data(lp, (u8 *)lp->deferred_skb->data,
				lp->deferred_skb->len))
		return;

	dev->stats.tx_bytes += lp->deferred_skb->len;
	dev_consume_skb_irq(lp->deferred_skb);
	lp->deferred_skb = NULL;
	netif_trans_update(dev); /* prevent tx timeout */
	netif_wake_queue(dev);
}


static int xemaclite_of_probe(struct platform_device *ofdev)
{
	struct resource *res;
	struct net_device *ndev = NULL;
	struct net_local *lp = NULL;
	struct device *dev = &ofdev->dev;

	int rc = 0;

	dev_info(dev, "Device Tree Probing\n");

	/* Create an ethernet device instance */
	ndev = alloc_etherdev(sizeof(struct net_local));
	if (!ndev)
		return -ENOMEM;

	dev_set_drvdata(dev, ndev);
	SET_NETDEV_DEV(ndev, &ofdev->dev);

	lp = netdev_priv(ndev);
	lp->ndev = ndev;

	/* Get IRQ for the device */
	res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
	if (!res) {
		dev_err(dev, "no IRQ found\n");
		rc = -ENXIO;
		goto error;
	}

	ndev->irq = res->start;

	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
	lp->base_addr = devm_ioremap_resource(&ofdev->dev, res);
	if (IS_ERR(lp->base_addr)) {
		rc = PTR_ERR(lp->base_addr);
		goto error;
	}

	ndev->mem_start = res->start;
	ndev->mem_end = res->end;

	spin_lock_init(&lp->reset_lock);
	lp->next_tx_buf_to_use = 0x0;
	lp->next_rx_buf_to_use = 0x0;
	lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
	lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");

	rc = of_get_mac_address(ofdev->dev.of_node, ndev->dev_addr);
	if (rc) {
		dev_warn(dev, "No MAC address found, using random\n");
		eth_hw_addr_random(ndev);
	}

	/* Clear the Tx CSR's in case this is a restart */
	xemaclite_writel(0, lp->base_addr + XEL_TSR_OFFSET);
	xemaclite_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);

	/* Set the MAC address in the EmacLite device */
	xemaclite_update_address(lp, ndev->dev_addr);

	lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
	xemaclite_mdio_setup(lp, &ofdev->dev);

	dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);

	ndev->netdev_ops = &xemaclite_netdev_ops;
	ndev->ethtool_ops = &xemaclite_ethtool_ops;
	ndev->flags &= ~IFF_MULTICAST;
	ndev->watchdog_timeo = TX_TIMEOUT;

	/* Finally, register the device */
	rc = register_netdev(ndev);
	if (rc) {
		dev_err(dev,
			"Cannot register network device, aborting\n");
		goto error;
	}

	dev_info(dev,
		 "Xilinx EmacLite at 0x%08lX mapped to 0x%p, irq=%d\n",
		 (unsigned long __force)ndev->mem_start, lp->base_addr, ndev->irq);
	return 0;

error:
	free_netdev(ndev);
	return rc;
}


static void xemaclite_tx_timeout(struct net_device *dev, unsigned int txqueue)
{
	struct net_local *lp = netdev_priv(dev);
	unsigned long flags;

	dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
		TX_TIMEOUT * 1000UL / HZ);

	dev->stats.tx_errors++;

	/* Reset the device */
	spin_lock_irqsave(&lp->reset_lock, flags);

	/* Shouldn't really be necessary, but shouldn't hurt */
	netif_stop_queue(dev);

	xemaclite_disable_interrupts(lp);
	xemaclite_enable_interrupts(lp);

	if (lp->deferred_skb) {
		dev_kfree_skb(lp->deferred_skb);
		lp->deferred_skb = NULL;
		dev->stats.tx_errors++;
	}

	/* To exclude tx timeout */
	netif_trans_update(dev); /* prevent tx timeout */

	/* We're all ready to go. Start the queue */
	netif_wake_queue(dev);
	spin_unlock_irqrestore(&lp->reset_lock, flags);
}


static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
{
	struct mii_bus *bus;
	int rc;
	struct resource res;
	struct device_node *np = of_get_parent(lp->phy_node);
	struct device_node *npp;

	/* Don't register the MDIO bus if the phy_node or its parent node
	 * can't be found.
	 */
	if (!np) {
		dev_err(dev, "Failed to register mdio bus.\n");
		return -ENODEV;
	}
	npp = of_get_parent(np);

	of_address_to_resource(npp, 0, &res);
	if (lp->ndev->mem_start != res.start) {
		struct phy_device *phydev;
		phydev = of_phy_find_device(lp->phy_node);
		if (!phydev)
			dev_info(dev,
				 "MDIO of the phy is not registered yet\n");
		else
			put_device(&phydev->mdio.dev);
		return 0;
	}

	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
	 * register.
	 */
	xemaclite_writel(XEL_MDIOCTRL_MDIOEN_MASK,
			 lp->base_addr + XEL_MDIOCTRL_OFFSET);

	bus = mdiobus_alloc();
	if (!bus) {
		dev_err(dev, "Failed to allocate mdiobus\n");
		return -ENOMEM;
	}

	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
		 (unsigned long long)res.start);
	bus->priv = lp;
	bus->name = "Xilinx Emaclite MDIO";
	bus->read = xemaclite_mdio_read;
	bus->write = xemaclite_mdio_write;
	bus->parent = dev;

	rc = of_mdiobus_register(bus, np);
	if (rc) {
		dev_err(dev, "Failed to register mdio bus.\n");
		goto err_register;
	}

	lp->mii_bus = bus;

	return 0;

err_register:
	mdiobus_free(bus);
	return rc;
}


static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
{
	bool tx_complete = false;
	struct net_device *dev = dev_id;
	struct net_local *lp = netdev_priv(dev);
	void __iomem *base_addr = lp->base_addr;
	u32 tx_status;

	/* Check if there is Rx Data available */
	if ((xemaclite_readl(base_addr + XEL_RSR_OFFSET) &
			 XEL_RSR_RECV_DONE_MASK) ||
	    (xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
			 & XEL_RSR_RECV_DONE_MASK))

		xemaclite_rx_handler(dev);

	/* Check if the Transmission for the first buffer is completed */
	tx_status = xemaclite_readl(base_addr + XEL_TSR_OFFSET);
	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {

		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
		xemaclite_writel(tx_status, base_addr + XEL_TSR_OFFSET);

		tx_complete = true;
	}

	/* Check if the Transmission for the second buffer is completed */
	tx_status = xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {

		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
		xemaclite_writel(tx_status, base_addr + XEL_BUFFER_OFFSET +
				 XEL_TSR_OFFSET);

		tx_complete = true;
	}

	/* If there was a Tx interrupt, call the Tx Handler */
	if (tx_complete != 0)
		xemaclite_tx_handler(dev);

	return IRQ_HANDLED;
}


static void xemaclite_adjust_link(struct net_device *ndev)
{
	struct net_local *lp = netdev_priv(ndev);
	struct phy_device *phy = lp->phy_dev;
	int link_state;

	/* hash together the state values to decide if something has changed */
	link_state = phy->speed | (phy->duplex << 1) | phy->link;

	if (lp->last_link != link_state) {
		lp->last_link = link_state;
		phy_print_status(phy);
	}
}


static int xemaclite_set_mac_address(struct net_device *dev, void *address)
{
	struct net_local *lp = netdev_priv(dev);
	struct sockaddr *addr = address;

	if (netif_running(dev))
		return -EBUSY;

	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
	xemaclite_update_address(lp, dev->dev_addr);
	return 0;
}


static void xemaclite_enable_interrupts(struct net_local *drvdata)
{
	u32 reg_data;

	/* Enable the Tx interrupts for the first Buffer */
	reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET);
	xemaclite_writel(reg_data | XEL_TSR_XMIT_IE_MASK,
			 drvdata->base_addr + XEL_TSR_OFFSET);

	/* Enable the Rx interrupts for the first buffer */
	xemaclite_writel(XEL_RSR_RECV_IE_MASK, drvdata->base_addr + XEL_RSR_OFFSET);

	/* Enable the Global Interrupt Enable */
	xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
}


static int xemaclite_close(struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);

	netif_stop_queue(dev);
	xemaclite_disable_interrupts(lp);
	free_irq(dev->irq, dev);

	if (lp->phy_dev)
		phy_disconnect(lp->phy_dev);
	lp->phy_dev = NULL;

	return 0;
}


static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
	if (!dev->phydev || !netif_running(dev))
		return -EINVAL;

	switch (cmd) {
	case SIOCGMIIPHY:
	case SIOCGMIIREG:
	case SIOCSMIIREG:
		return phy_mii_ioctl(dev->phydev, rq, cmd);
	default:
		return -EOPNOTSUPP;
	}
}


static int xemaclite_send_data(struct net_local *drvdata, u8 *data,
			       unsigned int byte_count)
{
	u32 reg_data;
	void __iomem *addr;

	/* Determine the expected Tx buffer address */
	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;

	/* If the length is too large, truncate it */
	if (byte_count > ETH_FRAME_LEN)
		byte_count = ETH_FRAME_LEN;

	/* Check if the expected buffer is available */
	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
	if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
	     XEL_TSR_XMIT_ACTIVE_MASK)) == 0) {

		/* Switch to next buffer if configured */
		if (drvdata->tx_ping_pong != 0)
			drvdata->next_tx_buf_to_use ^= XEL_BUFFER_OFFSET;
	} else if (drvdata->tx_ping_pong != 0) {
		/* If the expected buffer is full, try the other buffer,
		 * if it is configured in HW
		 */

		addr = (void __iomem __force *)((uintptr_t __force)addr ^
						 XEL_BUFFER_OFFSET);
		reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);

		if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
		     XEL_TSR_XMIT_ACTIVE_MASK)) != 0)
			return -1; /* Buffers were full, return failure */
	} else
		return -1; /* Buffer was full, return failure */

	/* Write the frame to the buffer */
	xemaclite_aligned_write(data, (u32 __force *)addr, byte_count);

	xemaclite_writel((byte_count & XEL_TPLR_LENGTH_MASK),
			 addr + XEL_TPLR_OFFSET);

	/* Update the Tx Status Register to indicate that there is a
	 * frame to send. Set the XEL_TSR_XMIT_ACTIVE_MASK flag which
	 * is used by the interrupt handler to check whether a frame
	 * has been transmitted
	 */
	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
	reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK);
	xemaclite_writel(reg_data, addr + XEL_TSR_OFFSET);

	return 0;
}


xemaclite_poll_controller(struct net_device *ndev)
{
	disable_irq(ndev->irq);
	xemaclite_interrupt(ndev->irq, ndev);
	enable_irq(ndev->irq);
}


static int xemaclite_open(struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);
	int retval;

	/* Just to be safe, stop the device first */
	xemaclite_disable_interrupts(lp);

	if (lp->phy_node) {
		u32 bmcr;

		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
					     xemaclite_adjust_link, 0,
					     PHY_INTERFACE_MODE_MII);
		if (!lp->phy_dev) {
			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
			return -ENODEV;
		}

		/* EmacLite doesn't support giga-bit speeds */
		phy_set_max_speed(lp->phy_dev, SPEED_100);

		/* Don't advertise 1000BASE-T Full/Half duplex speeds */
		phy_write(lp->phy_dev, MII_CTRL1000, 0);

		/* Advertise only 10 and 100mbps full/half duplex speeds */
		phy_write(lp->phy_dev, MII_ADVERTISE, ADVERTISE_ALL |
			  ADVERTISE_CSMA);

		/* Restart auto negotiation */
		bmcr = phy_read(lp->phy_dev, MII_BMCR);
		bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
		phy_write(lp->phy_dev, MII_BMCR, bmcr);

		phy_start(lp->phy_dev);
	}

	/* Set the MAC address each time opened */
	xemaclite_update_address(lp, dev->dev_addr);

	/* Grab the IRQ */
	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
	if (retval) {
		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
			dev->irq);
		if (lp->phy_dev)
			phy_disconnect(lp->phy_dev);
		lp->phy_dev = NULL;

		return retval;
	}

	/* Enable Interrupts */
	xemaclite_enable_interrupts(lp);

	/* We're ready to go */
	netif_start_queue(dev);

	return 0;
}


static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
{
	struct net_local *lp = bus->priv;
	u32 ctrl_reg;
	u32 rc;

	if (xemaclite_mdio_wait(lp))
		return -ETIMEDOUT;

	/* Write the PHY address, register number and set the OP bit in the
	 * MDIO Address register. Set the Status bit in the MDIO Control
	 * register to start a MDIO read transaction.
	 */
	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
	xemaclite_writel(XEL_MDIOADDR_OP_MASK |
			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
			 lp->base_addr + XEL_MDIOADDR_OFFSET);
	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
			 lp->base_addr + XEL_MDIOCTRL_OFFSET);

	if (xemaclite_mdio_wait(lp))
		return -ETIMEDOUT;

	rc = xemaclite_readl(lp->base_addr + XEL_MDIORD_OFFSET);

	dev_dbg(&lp->ndev->dev,
		"%s(phy_id=%i, reg=%x) == %x\n", __func__,
		phy_id, reg, rc);

	return rc;
}


static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
				u16 val)
{
	struct net_local *lp = bus->priv;
	u32 ctrl_reg;

	dev_dbg(&lp->ndev->dev,
		"%s(phy_id=%i, reg=%x, val=%x)\n", __func__,
		phy_id, reg, val);

	if (xemaclite_mdio_wait(lp))
		return -ETIMEDOUT;

	/* Write the PHY address, register number and clear the OP bit in the
	 * MDIO Address register and then write the value into the MDIO Write
	 * Data register. Finally, set the Status bit in the MDIO Control
	 * register to start a MDIO write transaction.
	 */
	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
	xemaclite_writel(~XEL_MDIOADDR_OP_MASK &
			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
			 lp->base_addr + XEL_MDIOADDR_OFFSET);
	xemaclite_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
			 lp->base_addr + XEL_MDIOCTRL_OFFSET);

	return 0;
}


static void xemaclite_disable_interrupts(struct net_local *drvdata)
{
	u32 reg_data;

	/* Disable the Global Interrupt Enable */
	xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);

	/* Disable the Tx interrupts for the first buffer */
	reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET);
	xemaclite_writel(reg_data & (~XEL_TSR_XMIT_IE_MASK),
			 drvdata->base_addr + XEL_TSR_OFFSET);

	/* Disable the Rx interrupts for the first buffer */
	reg_data = xemaclite_readl(drvdata->base_addr + XEL_RSR_OFFSET);
	xemaclite_writel(reg_data & (~XEL_RSR_RECV_IE_MASK),
			 drvdata->base_addr + XEL_RSR_OFFSET);
}


static int xemaclite_of_remove(struct platform_device *of_dev)
{
	struct net_device *ndev = platform_get_drvdata(of_dev);

	struct net_local *lp = netdev_priv(ndev);

	/* Un-register the mii_bus, if configured */
	if (lp->mii_bus) {
		mdiobus_unregister(lp->mii_bus);
		mdiobus_free(lp->mii_bus);
		lp->mii_bus = NULL;
	}

	unregister_netdev(ndev);

	of_node_put(lp->phy_node);
	lp->phy_node = NULL;

	free_netdev(ndev);

	return 0;
}


static int xemaclite_mdio_wait(struct net_local *lp)
{
	u32 val;

	/* wait for the MDIO interface to not be busy or timeout
	 * after some time.
	 */
	return readx_poll_timeout(xemaclite_readl,
				  lp->base_addr + XEL_MDIOCTRL_OFFSET,
				  val, !(val & XEL_MDIOCTRL_MDIOSTS_MASK),
				  1000, 20000);
}


static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data, int maxlen)
{
	void __iomem *addr;
	u16 length, proto_type;
	u32 reg_data;

	/* Determine the expected buffer address */
	addr = (drvdata->base_addr + drvdata->next_rx_buf_to_use);

	/* Verify which buffer has valid data */
	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);

	if ((reg_data & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
		if (drvdata->rx_ping_pong != 0)
			drvdata->next_rx_buf_to_use ^= XEL_BUFFER_OFFSET;
	} else {
		/* The instance is out of sync, try other buffer if other
		 * buffer is configured, return 0 otherwise. If the instance is
		 * out of sync, do not update the 'next_rx_buf_to_use' since it
		 * will correct on subsequent calls
		 */
		if (drvdata->rx_ping_pong != 0)
			addr = (void __iomem __force *)
				((uintptr_t __force)addr ^
				 XEL_BUFFER_OFFSET);
		else
			return 0;	/* No data was available */

		/* Verify that buffer has valid data */
		reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
		if ((reg_data & XEL_RSR_RECV_DONE_MASK) !=
		     XEL_RSR_RECV_DONE_MASK)
			return 0;	/* No data was available */
	}

	/* Get the protocol type of the ethernet frame that arrived
	 */
	proto_type = ((ntohl(xemaclite_readl(addr + XEL_HEADER_OFFSET +
			XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) &
			XEL_RPLR_LENGTH_MASK);

	/* Check if received ethernet frame is a raw ethernet frame
	 * or an IP packet or an ARP packet
	 */
	if (proto_type > ETH_DATA_LEN) {

		if (proto_type == ETH_P_IP) {
			length = ((ntohl(xemaclite_readl(addr +
					XEL_HEADER_IP_LENGTH_OFFSET +
					XEL_RXBUFF_OFFSET)) >>
					XEL_HEADER_SHIFT) &
					XEL_RPLR_LENGTH_MASK);
			length = min_t(u16, length, ETH_DATA_LEN);
			length += ETH_HLEN + ETH_FCS_LEN;

		} else if (proto_type == ETH_P_ARP)
			length = XEL_ARP_PACKET_SIZE + ETH_HLEN + ETH_FCS_LEN;
		else
			/* Field contains type other than IP or ARP, use max
			 * frame size and let user parse it
			 */
			length = ETH_FRAME_LEN + ETH_FCS_LEN;
	} else
		/* Use the length in the frame, plus the header and trailer */
		length = proto_type + ETH_HLEN + ETH_FCS_LEN;

	if (WARN_ON(length > maxlen))
		length = maxlen;

	/* Read from the EmacLite device */
	xemaclite_aligned_read((u32 __force *)(addr + XEL_RXBUFF_OFFSET),
				data, length);

	/* Acknowledge the frame */
	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
	reg_data &= ~XEL_RSR_RECV_DONE_MASK;
	xemaclite_writel(reg_data, addr + XEL_RSR_OFFSET);

	return length;
}


xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
{
	struct net_local *lp = netdev_priv(dev);
	struct sk_buff *new_skb;
	unsigned int len;
	unsigned long flags;

	len = orig_skb->len;

	new_skb = orig_skb;

	spin_lock_irqsave(&lp->reset_lock, flags);
	if (xemaclite_send_data(lp, (u8 *)new_skb->data, len) != 0) {
		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
		 * defer the skb for transmission during the ISR, after the
		 * current transmission is complete
		 */
		netif_stop_queue(dev);
		lp->deferred_skb = new_skb;
		/* Take the time stamp now, since we can't do this in an ISR. */
		skb_tx_timestamp(new_skb);
		spin_unlock_irqrestore(&lp->reset_lock, flags);
		return NETDEV_TX_OK;
	}
	spin_unlock_irqrestore(&lp->reset_lock, flags);

	skb_tx_timestamp(new_skb);

	dev->stats.tx_bytes += len;
	dev_consume_skb_any(new_skb);

	return NETDEV_TX_OK;
}


static void xemaclite_update_address(struct net_local *drvdata,
				     u8 *address_ptr)
{
	void __iomem *addr;
	u32 reg_data;

	/* Determine the expected Tx buffer address */
	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;

	xemaclite_aligned_write(address_ptr, (u32 __force *)addr, ETH_ALEN);

	xemaclite_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET);

	/* Update the MAC address in the EmacLite */
	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
	xemaclite_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET);

	/* Wait for EmacLite to finish with the MAC address update */
	while ((xemaclite_readl(addr + XEL_TSR_OFFSET) &
		XEL_TSR_PROG_MAC_ADDR) != 0)
		;
}


int main(int argc, char **argv)
{
	int c, rc = MOUNT_EX_SUCCESS, all = 0, show_labels = 0;
	struct libmnt_context *cxt;
	struct libmnt_table *fstab = NULL;
	char *srcbuf = NULL;
	char *types = NULL;
	unsigned long oper = 0;

	enum {
		MOUNT_OPT_SHARED = CHAR_MAX + 1,
		MOUNT_OPT_SLAVE,
		MOUNT_OPT_PRIVATE,
		MOUNT_OPT_UNBINDABLE,
		MOUNT_OPT_RSHARED,
		MOUNT_OPT_RSLAVE,
		MOUNT_OPT_RPRIVATE,
		MOUNT_OPT_RUNBINDABLE,
		MOUNT_OPT_TARGET,
		MOUNT_OPT_SOURCE
	};

	static const struct option longopts[] = {
		{ "all", 0, 0, 'a' },
		{ "fake", 0, 0, 'f' },
		{ "fstab", 1, 0, 'T' },
		{ "fork", 0, 0, 'F' },
		{ "help", 0, 0, 'h' },
		{ "no-mtab", 0, 0, 'n' },
		{ "read-only", 0, 0, 'r' },
		{ "ro", 0, 0, 'r' },
		{ "verbose", 0, 0, 'v' },
		{ "version", 0, 0, 'V' },
		{ "read-write", 0, 0, 'w' },
		{ "rw", 0, 0, 'w' },
		{ "options", 1, 0, 'o' },
		{ "test-opts", 1, 0, 'O' },
		{ "pass-fd", 1, 0, 'p' },
		{ "types", 1, 0, 't' },
		{ "uuid", 1, 0, 'U' },
		{ "label", 1, 0, 'L'},
		{ "bind", 0, 0, 'B' },
		{ "move", 0, 0, 'M' },
		{ "rbind", 0, 0, 'R' },
		{ "make-shared", 0, 0, MOUNT_OPT_SHARED },
		{ "make-slave", 0, 0, MOUNT_OPT_SLAVE },
		{ "make-private", 0, 0, MOUNT_OPT_PRIVATE },
		{ "make-unbindable", 0, 0, MOUNT_OPT_UNBINDABLE },
		{ "make-rshared", 0, 0, MOUNT_OPT_RSHARED },
		{ "make-rslave", 0, 0, MOUNT_OPT_RSLAVE },
		{ "make-rprivate", 0, 0, MOUNT_OPT_RPRIVATE },
		{ "make-runbindable", 0, 0, MOUNT_OPT_RUNBINDABLE },
		{ "no-canonicalize", 0, 0, 'c' },
		{ "internal-only", 0, 0, 'i' },
		{ "show-labels", 0, 0, 'l' },
		{ "target", 1, 0, MOUNT_OPT_TARGET },
		{ "source", 1, 0, MOUNT_OPT_SOURCE },
		{ NULL, 0, 0, 0 }
	};

	static const ul_excl_t excl[] = {       /* rows and cols in in ASCII order */
		{ 'B','M','R',			/* bind,move,rbind */
		   MOUNT_OPT_SHARED,   MOUNT_OPT_SLAVE,
		   MOUNT_OPT_PRIVATE,  MOUNT_OPT_UNBINDABLE,
		   MOUNT_OPT_RSHARED,  MOUNT_OPT_RSLAVE,
		   MOUNT_OPT_RPRIVATE, MOUNT_OPT_RUNBINDABLE },

		{ 'L','U', MOUNT_OPT_SOURCE },	/* label,uuid,source */
		{ 0 }
	};
	int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;

	sanitize_env();
	setlocale(LC_ALL, "");
	bindtextdomain(PACKAGE, LOCALEDIR);
	textdomain(PACKAGE);
	atexit(close_stdout);

	mnt_init_debug(0);
	cxt = mnt_new_context();
	if (!cxt)
		err(MOUNT_EX_SYSERR, _("libmount context allocation failed"));

	mnt_context_set_tables_errcb(cxt, table_parser_errcb);

	while ((c = getopt_long(argc, argv, "aBcfFhilL:Mno:O:p:rRsU:vVwt:T:",
					longopts, NULL)) != -1) {

		/* only few options are allowed for non-root users */
		if (mnt_context_is_restricted(cxt) &&
		    !strchr("hlLUVvpris", c) &&
		    c != MOUNT_OPT_TARGET &&
		    c != MOUNT_OPT_SOURCE)
			exit_non_root(option_to_longopt(c, longopts));

		err_exclusive_options(c, longopts, excl, excl_st);

		switch(c) {
		case 'a':
			all = 1;
			break;
		case 'c':
			mnt_context_disable_canonicalize(cxt, TRUE);
			break;
		case 'f':
			mnt_context_enable_fake(cxt, TRUE);
			break;
		case 'F':
			mnt_context_enable_fork(cxt, TRUE);
			break;
		case 'h':
			usage(stdout);
			break;
		case 'i':
			mnt_context_disable_helpers(cxt, TRUE);
			break;
		case 'n':
			mnt_context_disable_mtab(cxt, TRUE);
			break;
		case 'r':
			if (mnt_context_append_options(cxt, "ro"))
				err(MOUNT_EX_SYSERR, _("failed to append options"));
			readwrite = 0;
			break;
		case 'v':
			mnt_context_enable_verbose(cxt, TRUE);
			break;
		case 'V':
			print_version();
			break;
		case 'w':
			if (mnt_context_append_options(cxt, "rw"))
				err(MOUNT_EX_SYSERR, _("failed to append options"));
			readwrite = 1;
			break;
		case 'o':
			if (mnt_context_append_options(cxt, optarg))
				err(MOUNT_EX_SYSERR, _("failed to append options"));
			break;
		case 'O':
			if (mnt_context_set_options_pattern(cxt, optarg))
				err(MOUNT_EX_SYSERR, _("failed to set options pattern"));
			break;
		case 'p':
                        warnx(_("--pass-fd is no longer supported"));
			break;
		case 'L':
			xasprintf(&srcbuf, "LABEL=\"%s\"", optarg);
			mnt_context_disable_swapmatch(cxt, 1);
			mnt_context_set_source(cxt, srcbuf);
			free(srcbuf);
			break;
		case 'U':
			xasprintf(&srcbuf, "UUID=\"%s\"", optarg);
			mnt_context_disable_swapmatch(cxt, 1);
			mnt_context_set_source(cxt, srcbuf);
			free(srcbuf);
			break;
		case 'l':
			show_labels = 1;
			break;
		case 't':
			types = optarg;
			break;
		case 'T':
			fstab = append_fstab(cxt, fstab, optarg);
			break;
		case 's':
			mnt_context_enable_sloppy(cxt, TRUE);
			break;
		case 'B':
			oper |= MS_BIND;
			break;
		case 'M':
			oper |= MS_MOVE;
			break;
		case 'R':
			oper |= (MS_BIND | MS_REC);
			break;
		case MOUNT_OPT_SHARED:
			oper |= MS_SHARED;
			break;
		case MOUNT_OPT_SLAVE:
			oper |= MS_SLAVE;
			break;
		case MOUNT_OPT_PRIVATE:
			oper |= MS_PRIVATE;
			break;
		case MOUNT_OPT_UNBINDABLE:
			oper |= MS_UNBINDABLE;
			break;
		case MOUNT_OPT_RSHARED:
			oper |= (MS_SHARED | MS_REC);
			break;
		case MOUNT_OPT_RSLAVE:
			oper |= (MS_SLAVE | MS_REC);
			break;
		case MOUNT_OPT_RPRIVATE:
			oper |= (MS_PRIVATE | MS_REC);
			break;
		case MOUNT_OPT_RUNBINDABLE:
			oper |= (MS_UNBINDABLE | MS_REC);
			break;
		case MOUNT_OPT_TARGET:
			mnt_context_disable_swapmatch(cxt, 1);
			mnt_context_set_target(cxt, optarg);
			break;
		case MOUNT_OPT_SOURCE:
			mnt_context_disable_swapmatch(cxt, 1);
			mnt_context_set_source(cxt, optarg);
			break;
		default:
			usage(stderr);
			break;
		}
	}

	argc -= optind;
	argv += optind;

	if (fstab && !mnt_context_is_nocanonicalize(cxt)) {
		/*
		 * We have external (context independent) fstab instance, let's
		 * make a connection between the fstab and the canonicalization
		 * cache.
		 */
		struct libmnt_cache *cache = mnt_context_get_cache(cxt);
		mnt_table_set_cache(fstab, cache);
	}

	if (!mnt_context_get_source(cxt) &&
	    !mnt_context_get_target(cxt) &&
	    !argc &&
	    !all) {
		if (oper)
			usage(stderr);
		print_all(cxt, types, show_labels);
		goto done;
	}

	if (oper && (types || all || mnt_context_get_source(cxt)))
		usage(stderr);

	if (types && (all || strchr(types, ',') ||
			     strncmp(types, "no", 2) == 0))
		mnt_context_set_fstype_pattern(cxt, types);
	else if (types)
		mnt_context_set_fstype(cxt, types);

	if (all) {
		/*
		 * A) Mount all
		 */
		rc = mount_all(cxt);
		goto done;

	} else if (argc == 0 && (mnt_context_get_source(cxt) ||
				 mnt_context_get_target(cxt))) {
		/*
		 * B) mount -L|-U|--source|--target
		 */
		if (mnt_context_is_restricted(cxt) &&
		    mnt_context_get_source(cxt) &&
		    mnt_context_get_target(cxt))
			exit_non_root(NULL);

	} else if (argc == 1) {
		/*
		 * C) mount [-L|-U|--source] <target>
		 *    mount <source|target>
		 *
		 * non-root may specify source *or* target, but not both
		 */
		if (mnt_context_is_restricted(cxt) &&
		    mnt_context_get_source(cxt))
			exit_non_root(NULL);

		mnt_context_set_target(cxt, argv[0]);

	} else if (argc == 2 && !mnt_context_get_source(cxt)
			     && !mnt_context_get_target(cxt)) {
		/*
		 * D) mount <source> <target>
		 */
		if (mnt_context_is_restricted(cxt))
			exit_non_root(NULL);
		mnt_context_set_source(cxt, argv[0]);
		mnt_context_set_target(cxt, argv[1]);

	} else
		usage(stderr);

	if (mnt_context_is_restricted(cxt))
		sanitize_paths(cxt);

	if (oper) {
		/* MS_PROPAGATION operations, let's set the mount flags */
		mnt_context_set_mflags(cxt, oper);

		/* For -make* or --bind is fstab unnecessary */
		mnt_context_set_optsmode(cxt, MNT_OMODE_NOTAB);
	}

	rc = mnt_context_mount(cxt);
	rc = mk_exit_code(cxt, rc);

	if (rc == MOUNT_EX_SUCCESS && mnt_context_is_verbose(cxt))
		success_message(cxt);
done:
	mnt_free_context(cxt);
	mnt_free_table(fstab);
	return rc;
}

mount: sanitize paths from non-root users

 $ mount /root/.ssh/../../dev/sda2
 mount: only root can mount UUID=17bc65ec-4125-4e7c-8a7d-e2795064c736 on /boot

this is too promiscuous. It seems better to ignore on command line
specified paths which are not resolve-able for non-root users.

Fixed version:

  $ mount /root/.ssh/../../dev/sda2
  mount: /root/.ssh/../../dev/sda2: Permission denied

  $ mount /dev/sda2
  mount: only root can mount UUID=17bc65ec-4125-4e7c-8a7d-e2795064c736 on /boot

Note that this bug has no relation to mount(2) permissions evaluation
in suid mode. The way how non-root user specifies paths on command
line is completely irrelevant for comparison with fstab entries.

Signed-off-by: Karel Zak <kzak@redhat.com>


static void safe_fputs(const char *data)
{
	const char *p;

	for (p = data; p && *p; p++) {
		if (iscntrl((unsigned char) *p))
			fputc('?', stdout);
		else
			fputc(*p, stdout);
	}
}


static void success_message(struct libmnt_context *cxt)
{
	unsigned long mflags = 0;
	const char *tgt, *src;

	if (mnt_context_helper_executed(cxt)
	    || mnt_context_get_status(cxt) != 1)
		return;

	mnt_context_get_mflags(cxt, &mflags);
	tgt = mnt_context_get_target(cxt);
	src = mnt_context_get_source(cxt);

	if (mflags & MS_MOVE)
		warnx(_("%s moved to %s"), src, tgt);
	else if (mflags & MS_BIND)
		warnx(_("%s binded on %s"), src, tgt);
	else if (mflags & MS_PROPAGATION)
		warnx(_("%s propagation flags changed"), tgt);
	else
		warnx(_("%s mounted on %s"), src, tgt);
}


static int table_parser_errcb(struct libmnt_table *tb __attribute__((__unused__)),
			const char *filename, int line)
{
	if (filename)
		warnx(_("%s: parse error: ignore entry at line %d."),
							filename, line);
	return 0;
}


static struct libmnt_table *append_fstab(struct libmnt_context *cxt,
					 struct libmnt_table *fstab,
					 const char *path)
{

	if (!fstab) {
		fstab = mnt_new_table();
		if (!fstab)
			err(MOUNT_EX_SYSERR, _("failed to initialize libmount table"));

		mnt_table_set_parser_errcb(fstab, table_parser_errcb);
		mnt_context_set_fstab(cxt, fstab);
	}

	if (mnt_table_parse_fstab(fstab, path))
		errx(MOUNT_EX_USAGE,_("%s: failed to parse"), path);

	return fstab;
}


static int handle_generic_errors(int rc, const char *msg, ...)
{
	va_list va;

	va_start(va, msg);
	errno = -rc;

	switch(errno) {
	case EINVAL:
	case EPERM:
		vwarn(msg, va);
		rc = MOUNT_EX_USAGE;
		break;
	case ENOMEM:
		vwarn(msg, va);
		rc = MOUNT_EX_SYSERR;
		break;
	default:
		vwarn(msg, va);
		rc = MOUNT_EX_FAIL;
		break;
	}
	va_end(va);
	return rc;
}


static int mk_exit_code(struct libmnt_context *cxt, int rc)
{
	int syserr;
	struct stat st;
	unsigned long uflags = 0, mflags = 0;

	int restricted = mnt_context_is_restricted(cxt);
	const char *tgt = mnt_context_get_target(cxt);
	const char *src = mnt_context_get_source(cxt);

try_readonly:
	if (mnt_context_helper_executed(cxt))
		/*
		 * /sbin/mount.<type> called, return status
		 */
		return mnt_context_get_helper_status(cxt);

	if (rc == 0 && mnt_context_get_status(cxt) == 1) {
		/*
		 * Libmount success && syscall success.
		 */
		selinux_warning(cxt, tgt);

		return MOUNT_EX_SUCCESS;	/* mount(2) success */
	}

	mnt_context_get_mflags(cxt, &mflags);		/* mount(2) flags */
	mnt_context_get_user_mflags(cxt, &uflags);	/* userspace flags */

	if (!mnt_context_syscall_called(cxt)) {
		/*
		 * libmount errors (extra library checks)
		 */
		switch (rc) {
		case -EPERM:
			warnx(_("only root can mount %s on %s"), src, tgt);
			return MOUNT_EX_USAGE;
		case -EBUSY:
			warnx(_("%s is already mounted"), src);
			return MOUNT_EX_USAGE;
		case -MNT_ERR_NOFSTAB:
			if (mnt_context_is_swapmatch(cxt)) {
				warnx(_("can't find %s in %s"),
						src ? src : tgt,
						mnt_get_fstab_path());
				return MOUNT_EX_USAGE;
			}
			/* source/target explicitly defined */
			if (tgt)
				warnx(_("can't find mountpoint %s in %s"),
						tgt, mnt_get_fstab_path());
			else
				warnx(_("can't find mount source %s in %s"),
						src, mnt_get_fstab_path());
			return MOUNT_EX_USAGE;
		case -MNT_ERR_NOFSTYPE:
			if (restricted)
				warnx(_("I could not determine the filesystem type, "
					"and none was specified"));
			else
				warnx(_("you must specify the filesystem type"));
			return MOUNT_EX_USAGE;
		case -MNT_ERR_NOSOURCE:
			if (src)
				warnx(_("can't find %s"), src);
			else
				warnx(_("mount source not defined"));
			return MOUNT_EX_USAGE;
		case -MNT_ERR_MOUNTOPT:
			if (errno)
				warn(_("failed to parse mount options"));
			else
				warnx(_("failed to parse mount options"));
			return MOUNT_EX_USAGE;
		case -MNT_ERR_LOOPDEV:
			warn(_("%s: failed to setup loop device"), src);
			return MOUNT_EX_FAIL;
		default:
			return handle_generic_errors(rc, _("%s: mount failed"),
					     tgt ? tgt : src);
		}
	} else if (mnt_context_get_syscall_errno(cxt) == 0) {
		/*
		 * mount(2) syscall success, but something else failed
		 * (probably error in mtab processing).
		 */
		if (rc < 0)
			return handle_generic_errors(rc,
				_("%s: filesystem mounted, but mount(8) failed"),
				tgt ? tgt : src);

		return MOUNT_EX_SOFTWARE;	/* internal error */

	}

	/*
	 * mount(2) errors
	 */
	syserr = mnt_context_get_syscall_errno(cxt);

	switch(syserr) {
	case EPERM:
		if (geteuid() == 0) {
			if (stat(tgt, &st) || !S_ISDIR(st.st_mode))
				warnx(_("mount point %s is not a directory"), tgt);
			else
				warnx(_("permission denied"));
		} else
			warnx(_("must be superuser to use mount"));
	      break;

	case EBUSY:
	{
		struct libmnt_table *tb;

		if (mflags & MS_REMOUNT) {
			warnx(_("%s is busy"), tgt);
			break;
		}

		warnx(_("%s is already mounted or %s busy"), src, tgt);

		if (src && mnt_context_get_mtab(cxt, &tb) == 0) {
			struct libmnt_iter *itr = mnt_new_iter(MNT_ITER_FORWARD);
			struct libmnt_fs *fs;

			while(mnt_table_next_fs(tb, itr, &fs) == 0) {
				const char *s = mnt_fs_get_srcpath(fs),
					   *t = mnt_fs_get_target(fs);

				if (t && s && mnt_fs_streq_srcpath(fs, src))
					fprintf(stderr, _(
						"       %s is already mounted on %s\n"), s, t);
			}
			mnt_free_iter(itr);
		}
		break;
	}
	case ENOENT:
		if (lstat(tgt, &st))
			warnx(_("mount point %s does not exist"), tgt);
		else if (stat(tgt, &st))
			warnx(_("mount point %s is a symbolic link to nowhere"), tgt);
		else if (stat(src, &st)) {
			if (uflags & MNT_MS_NOFAIL)
				return MOUNT_EX_SUCCESS;

			warnx(_("special device %s does not exist"), src);
		} else {
			errno = syserr;
			warn(_("mount(2) failed"));	/* print errno */
		}
		break;

	case ENOTDIR:
		if (stat(tgt, &st) || ! S_ISDIR(st.st_mode))
			warnx(_("mount point %s is not a directory"), tgt);
		else if (stat(src, &st) && errno == ENOTDIR) {
			if (uflags & MNT_MS_NOFAIL)
				return MOUNT_EX_SUCCESS;

			warnx(_("special device %s does not exist "
				 "(a path prefix is not a directory)"), src);
		} else {
			errno = syserr;
			warn(_("mount(2) failed"));     /* print errno */
		}
		break;

	case EINVAL:
		if (mflags & MS_REMOUNT)
			warnx(_("%s not mounted or bad option"), tgt);
		else if (mflags & MS_PROPAGATION)
			warnx(_("%s is not mountpoint or bad option"), tgt);
		else
			warnx(_("wrong fs type, bad option, bad superblock on %s,\n"
				"       missing codepage or helper program, or other error"),
				src);

		if (mnt_fs_is_netfs(mnt_context_get_fs(cxt)))
			fprintf(stderr, _(
				"       (for several filesystems (e.g. nfs, cifs) you might\n"
				"       need a /sbin/mount.<type> helper program)\n"));

		fprintf(stderr, _(
				"       In some cases useful info is found in syslog - try\n"
				"       dmesg | tail or so\n"));
		break;

	case EMFILE:
		warnx(_("mount table full"));
		break;

	case EIO:
		warnx(_("%s: can't read superblock"), src);
		break;

	case ENODEV:
		warnx(_("unknown filesystem type '%s'"), mnt_context_get_fstype(cxt));
		break;

	case ENOTBLK:
		if (uflags & MNT_MS_NOFAIL)
			return MOUNT_EX_SUCCESS;

		if (stat(src, &st))
			warnx(_("%s is not a block device, and stat(2) fails?"), src);
		else if (S_ISBLK(st.st_mode))
			warnx(_("the kernel does not recognize %s as a block device\n"
				"       (maybe `modprobe driver'?)"), src);
		else if (S_ISREG(st.st_mode))
			warnx(_("%s is not a block device (maybe try `-o loop'?)"), src);
		else
			warnx(_(" %s is not a block device"), src);
		break;

	case ENXIO:
		if (uflags & MNT_MS_NOFAIL)
			return MOUNT_EX_SUCCESS;

		warnx(_("%s is not a valid block device"), src);
		break;

	case EACCES:
	case EROFS:
		if (mflags & MS_RDONLY)
			warnx(_("cannot mount %s read-only"), src);

		else if (readwrite)
			warnx(_("%s is write-protected but explicit `-w' flag given"), src);

		else if (mflags & MS_REMOUNT)
			warnx(_("cannot remount %s read-write, is write-protected"), src);

		else {
			warnx(_("%s is write-protected, mounting read-only"), src);

			mnt_context_reset_status(cxt);
			mnt_context_set_mflags(cxt, mflags | MS_RDONLY);
			rc = mnt_context_do_mount(cxt);
			if (!rc)
				rc = mnt_context_finalize_mount(cxt);

			goto try_readonly;
		}
		break;

	case ENOMEDIUM:
		warnx(_("no medium found on %s"), src);
		break;

	default:
		warn(_("mount %s on %s failed"), src, tgt);
		break;
	}

	return MOUNT_EX_FAIL;
}


static void sanitize_paths(struct libmnt_context *cxt)
{
	const char *p;
	struct libmnt_fs *fs = mnt_context_get_fs(cxt);

	if (!fs)
		return;

	p = mnt_fs_get_target(fs);
	if (p) {
		char *np = canonicalize_path_restricted(p);
		if (!np)
			err(MOUNT_EX_USAGE, "%s", p);
		mnt_fs_set_target(fs, np);
		free(np);
	}

	p = mnt_fs_get_srcpath(fs);
	if (p) {
		char *np = canonicalize_path_restricted(p);
		if (!np)
			err(MOUNT_EX_USAGE, "%s", p);
		mnt_fs_set_source(fs, np);
		free(np);
	}
}


static void print_all(struct libmnt_context *cxt, char *pattern, int show_label)
{
	struct libmnt_table *tb;
	struct libmnt_iter *itr = NULL;
	struct libmnt_fs *fs;
	struct libmnt_cache *cache = NULL;

	if (mnt_context_get_mtab(cxt, &tb))
		err(MOUNT_EX_SYSERR, _("failed to read mtab"));

	itr = mnt_new_iter(MNT_ITER_FORWARD);
	if (!itr)
		err(MOUNT_EX_SYSERR, _("failed to initialize libmount iterator"));
	if (show_label)
		cache = mnt_new_cache();

	while (mnt_table_next_fs(tb, itr, &fs) == 0) {
		const char *type = mnt_fs_get_fstype(fs);
		const char *src = mnt_fs_get_source(fs);
		const char *optstr = mnt_fs_get_options(fs);
		char *xsrc = NULL;

		if (type && pattern && !mnt_match_fstype(type, pattern))
			continue;

		if (!mnt_fs_is_pseudofs(fs))
			xsrc = mnt_pretty_path(src, cache);
		printf ("%s on ", xsrc ? xsrc : src);
		safe_fputs(mnt_fs_get_target(fs));

		if (type)
			printf (" type %s", type);
		if (optstr)
			printf (" (%s)", optstr);
		if (show_label && src) {
			char *lb = mnt_cache_find_tag_value(cache, src, "LABEL");
			if (lb)
				printf (" [%s]", lb);
		}
		fputc('\n', stdout);
		free(xsrc);
	}

	mnt_free_cache(cache);
	mnt_free_iter(itr);
}


static void __attribute__((__noreturn__)) usage(FILE *out)
{
	fputs(USAGE_HEADER, out);
	fprintf(out, _(
		" %1$s [-lhV]\n"
		" %1$s -a [options]\n"
		" %1$s [options] [--source] <source> | [--target] <directory>\n"
		" %1$s [options] <source> <directory>\n"
		" %1$s <operation> <mountpoint> [<target>]\n"),
		program_invocation_short_name);

	fputs(USAGE_OPTIONS, out);
	fprintf(out, _(
	" -a, --all               mount all filesystems mentioned in fstab\n"
	" -c, --no-canonicalize   don't canonicalize paths\n"
	" -f, --fake              dry run; skip the mount(2) syscall\n"
	" -F, --fork              fork off for each device (use with -a)\n"
	" -T, --fstab <path>      alternative file to /etc/fstab\n"));
	fprintf(out, _(
	" -h, --help              display this help text and exit\n"
	" -i, --internal-only     don't call the mount.<type> helpers\n"
	" -l, --show-labels       lists all mounts with LABELs\n"
	" -n, --no-mtab           don't write to /etc/mtab\n"));
	fprintf(out, _(
	" -o, --options <list>    comma-separated list of mount options\n"
	" -O, --test-opts <list>  limit the set of filesystems (use with -a)\n"
	" -r, --read-only         mount the filesystem read-only (same as -o ro)\n"
	" -t, --types <list>      limit the set of filesystem types\n"));
	fprintf(out, _(
	"     --source <src>      explicitly specifies source (path, label, uuid)\n"
	"     --target <target>   explicitly specifies mountpoint\n"));
	fprintf(out, _(
	" -v, --verbose           say what is being done\n"
	" -V, --version           display version information and exit\n"
	" -w, --read-write        mount the filesystem read-write (default)\n"));

	fputs(USAGE_SEPARATOR, out);
	fputs(USAGE_HELP, out);
	fputs(USAGE_VERSION, out);

	fprintf(out, _(
	"\nSource:\n"
	" -L, --label <label>     synonym for LABEL=<label>\n"
	" -U, --uuid <uuid>       synonym for UUID=<uuid>\n"
	" LABEL=<label>           specifies device by filesystem label\n"
	" UUID=<uuid>             specifies device by filesystem UUID\n"
	" PARTLABEL=<label>       specifies device by partition label\n"
	" PARTUUID=<uuid>         specifies device by partition UUID\n"));

	fprintf(out, _(
	" <device>                specifies device by path\n"
	" <directory>             mountpoint for bind mounts (see --bind/rbind)\n"
	" <file>                  regular file for loopdev setup\n"));

	fprintf(out, _(
	"\nOperations:\n"
	" -B, --bind              mount a subtree somewhere else (same as -o bind)\n"
	" -M, --move              move a subtree to some other place\n"
	" -R, --rbind             mount a subtree and all submounts somewhere else\n"));
	fprintf(out, _(
	" --make-shared           mark a subtree as shared\n"
	" --make-slave            mark a subtree as slave\n"
	" --make-private          mark a subtree as private\n"
	" --make-unbindable       mark a subtree as unbindable\n"));
	fprintf(out, _(
	" --make-rshared          recursively mark a whole subtree as shared\n"
	" --make-rslave           recursively mark a whole subtree as slave\n"
	" --make-rprivate         recursively mark a whole subtree as private\n"
	" --make-runbindable      recursively mark a whole subtree as unbindable\n"));

	fprintf(out, USAGE_MAN_TAIL("mount(8)"));

	exit(out == stderr ? MOUNT_EX_USAGE : MOUNT_EX_SUCCESS);
}


static void __attribute__((__noreturn__)) print_version(void)
{
	const char *ver = NULL;
	const char **features = NULL, **p;

	mnt_get_library_version(&ver);
	mnt_get_library_features(&features);

	printf(_("%s from %s (libmount %s"),
			program_invocation_short_name,
			PACKAGE_STRING,
			ver);
	p = features;
	while (p && *p) {
		fputs(p == features ? ": " : ", ", stdout);
		fputs(*p++, stdout);
	}
	fputs(")\n", stdout);
	exit(MOUNT_EX_SUCCESS);
}