Commit 9dfedb8d authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'net-second-round-to-use-dev_net_rcu' 

Eric Dumazet says:

====================
net: second round to use dev_net_rcu()

dev_net(dev) should either be protected by RTNL or RCU.

There is no LOCKDEP support yet for this helper.

Adding it would trigger too many splats.

This second series fixes some of them.
====================

Link: https://patch.msgid.link/20250207135841.1948589-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents cb6cc8ed 087c1faa

include/net/l3mdev.h

+2 −0
Original line number Diff line number Diff line
@@ -198,10 +198,12 @@ struct sk_buff *l3mdev_l3_out(struct sock *sk, struct sk_buff *skb, u16 proto) 
	if (netif_is_l3_slave(dev)) {

		struct net_device *master;



		rcu_read_lock();

		master = netdev_master_upper_dev_get_rcu(dev);

		if (master && master->l3mdev_ops->l3mdev_l3_out)

			skb = master->l3mdev_ops->l3mdev_l3_out(master, sk,

								skb, proto);

		rcu_read_unlock();

	}



	return skb;

net/core/neighbour.c

+6 −2
Original line number Diff line number Diff line
@@ -3447,10 +3447,12 @@ static const struct seq_operations neigh_stat_seq_ops = { 
static void __neigh_notify(struct neighbour *n, int type, int flags,

			   u32 pid)

{

	struct net *net = dev_net(n->dev);

	struct sk_buff *skb;

	int err = -ENOBUFS;

	struct net *net;



	rcu_read_lock();

	net = dev_net_rcu(n->dev);

	skb = nlmsg_new(neigh_nlmsg_size(), GFP_ATOMIC);

	if (skb == NULL)

		goto errout;
@@ -3463,9 +3465,11 @@ static void __neigh_notify(struct neighbour *n, int type, int flags, 
		goto errout;

	}

	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);

	return;

	goto out;

errout:

	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);

out:

	rcu_read_unlock();

}



void neigh_app_ns(struct neighbour *n)

net/ipv4/arp.c

+3 −1
Original line number Diff line number Diff line
@@ -659,10 +659,12 @@ static int arp_xmit_finish(struct net *net, struct sock *sk, struct sk_buff *skb 
 */

void arp_xmit(struct sk_buff *skb)

{

	rcu_read_lock();

	/* Send it off, maybe filter it using firewalling first.  */

	NF_HOOK(NFPROTO_ARP, NF_ARP_OUT,

		dev_net(skb->dev), NULL, skb, NULL, skb->dev,

		dev_net_rcu(skb->dev), NULL, skb, NULL, skb->dev,

		arp_xmit_finish);

	rcu_read_unlock();

}

EXPORT_SYMBOL(arp_xmit);

net/ipv6/mcast.c

+15 −16
Original line number Diff line number Diff line
@@ -2165,21 +2165,21 @@ static void mld_send_cr(struct inet6_dev *idev) 


static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)

{

	struct net *net = dev_net(dev);

	struct sock *sk = net->ipv6.igmp_sk;

	const struct in6_addr *snd_addr, *saddr;

	int err, len, payload_len, full_len;

	struct in6_addr addr_buf;

	struct inet6_dev *idev;

	struct sk_buff *skb;

	struct mld_msg *hdr;

	const struct in6_addr *snd_addr, *saddr;

	struct in6_addr addr_buf;

	int hlen = LL_RESERVED_SPACE(dev);

	int tlen = dev->needed_tailroom;

	int err, len, payload_len, full_len;

	u8 ra[8] = { IPPROTO_ICMPV6, 0,

		     IPV6_TLV_ROUTERALERT, 2, 0, 0,

		     IPV6_TLV_PADN, 0 };

	struct flowi6 fl6;

	struct dst_entry *dst;

	struct flowi6 fl6;

	struct net *net;

	struct sock *sk;



	if (type == ICMPV6_MGM_REDUCTION)

		snd_addr = &in6addr_linklocal_allrouters;
@@ -2190,19 +2190,21 @@ static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type) 
	payload_len = len + sizeof(ra);

	full_len = sizeof(struct ipv6hdr) + payload_len;



	rcu_read_lock();

	IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_OUTREQUESTS);

	rcu_read_unlock();

	skb = alloc_skb(hlen + tlen + full_len, GFP_KERNEL);



	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);

	rcu_read_lock();



	net = dev_net_rcu(dev);

	idev = __in6_dev_get(dev);

	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);

	if (!skb) {

		rcu_read_lock();

		IP6_INC_STATS(net, __in6_dev_get(dev),

			      IPSTATS_MIB_OUTDISCARDS);

		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);

		rcu_read_unlock();

		return;

	}

	sk = net->ipv6.igmp_sk;

	skb_set_owner_w(skb, sk);



	skb->priority = TC_PRIO_CONTROL;

	skb_reserve(skb, hlen);
@@ -2227,9 +2229,6 @@ static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type) 
					 IPPROTO_ICMPV6,

					 csum_partial(hdr, len, 0));



	rcu_read_lock();

	idev = __in6_dev_get(skb->dev);



	icmpv6_flow_init(sk, &fl6, type,

			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,

			 skb->dev->ifindex);

net/ipv6/ndisc.c

+13 −11
Original line number Diff line number Diff line
@@ -418,15 +418,11 @@ static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, 
{

	int hlen = LL_RESERVED_SPACE(dev);

	int tlen = dev->needed_tailroom;

	struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;

	struct sk_buff *skb;



	skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);

	if (!skb) {

		ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n",

			  __func__);

	if (!skb)

		return NULL;

	}



	skb->protocol = htons(ETH_P_IPV6);

	skb->dev = dev;
@@ -437,7 +433,9 @@ static struct sk_buff *ndisc_alloc_skb(struct net_device *dev, 
	/* Manually assign socket ownership as we avoid calling

	 * sock_alloc_send_pskb() to bypass wmem buffer limits

	 */

	skb_set_owner_w(skb, sk);

	rcu_read_lock();

	skb_set_owner_w(skb, dev_net_rcu(dev)->ipv6.ndisc_sk);

	rcu_read_unlock();



	return skb;

}
@@ -473,16 +471,20 @@ static void ip6_nd_hdr(struct sk_buff *skb, 
void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr,

		    const struct in6_addr *saddr)

{

	struct icmp6hdr *icmp6h = icmp6_hdr(skb);

	struct dst_entry *dst = skb_dst(skb);

	struct net *net = dev_net(skb->dev);

	struct sock *sk = net->ipv6.ndisc_sk;

	struct inet6_dev *idev;

	struct net *net;

	struct sock *sk;

	int err;

	struct icmp6hdr *icmp6h = icmp6_hdr(skb);

	u8 type;



	type = icmp6h->icmp6_type;



	rcu_read_lock();



	net = dev_net_rcu(skb->dev);

	sk = net->ipv6.ndisc_sk;

	if (!dst) {

		struct flowi6 fl6;

		int oif = skb->dev->ifindex;
@@ -490,6 +492,7 @@ void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr, 
		icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);

		dst = icmp6_dst_alloc(skb->dev, &fl6);

		if (IS_ERR(dst)) {

			rcu_read_unlock();

			kfree_skb(skb);

			return;

		}
@@ -504,7 +507,6 @@ void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr, 


	ip6_nd_hdr(skb, saddr, daddr, READ_ONCE(inet6_sk(sk)->hop_limit), skb->len);



	rcu_read_lock();

	idev = __in6_dev_get(dst->dev);

	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
@@ -1694,7 +1696,7 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) 
	bool ret;



	if (netif_is_l3_master(skb->dev)) {

		dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif);

		dev = dev_get_by_index_rcu(dev_net(skb->dev), IPCB(skb)->iif);

		if (!dev)

			return;

	}