diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1c4b91136fd08..c676b04f89f0e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2683,6 +2683,12 @@ struct net *dev_net(const struct net_device *dev) return read_pnet(&dev->nd_net); } +static inline +struct net *dev_net_rcu(const struct net_device *dev) +{ + return read_pnet_rcu(&dev->nd_net); +} + static inline void dev_net_set(struct net_device *dev, struct net *net) { diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index d8ddfd69d0b35..3e7fb0bf340f2 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -350,21 +350,30 @@ static inline void put_net_track(struct net *net, netns_tracker *tracker) typedef struct { #ifdef CONFIG_NET_NS - struct net *net; + struct net __rcu *net; #endif } possible_net_t; static inline void write_pnet(possible_net_t *pnet, struct net *net) { #ifdef CONFIG_NET_NS - pnet->net = net; + rcu_assign_pointer(pnet->net, net); #endif } static inline struct net *read_pnet(const possible_net_t *pnet) { #ifdef CONFIG_NET_NS - return pnet->net; + return rcu_dereference_protected(pnet->net, true); +#else + return &init_net; +#endif +} + +static inline struct net *read_pnet_rcu(const possible_net_t *pnet) +{ +#ifdef CONFIG_NET_NS + return rcu_dereference(pnet->net); #else return &init_net; #endif diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 2ab784484ca27..c9f12ddc5a3b9 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -414,15 +414,11 @@ 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; @@ -433,7 +429,9 @@ 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; }