diff options
Diffstat (limited to 'net/ipv6/ip6_input.c')
-rw-r--r-- | net/ipv6/ip6_input.c | 41 |
1 files changed, 37 insertions, 4 deletions
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index d432d0011c16..7b089d0ac8cd 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -86,11 +86,27 @@ static void ip6_sublist_rcv_finish(struct list_head *head) } } +static bool ip6_can_use_hint(const struct sk_buff *skb, + const struct sk_buff *hint) +{ + return hint && !skb_dst(skb) && + ipv6_addr_equal(&ipv6_hdr(hint)->daddr, &ipv6_hdr(skb)->daddr); +} + +static struct sk_buff *ip6_extract_route_hint(const struct net *net, + struct sk_buff *skb) +{ + if (fib6_routes_require_src(net) || fib6_has_custom_rules(net)) + return NULL; + + return skb; +} + static void ip6_list_rcv_finish(struct net *net, struct sock *sk, struct list_head *head) { + struct sk_buff *skb, *next, *hint = NULL; struct dst_entry *curr_dst = NULL; - struct sk_buff *skb, *next; struct list_head sublist; INIT_LIST_HEAD(&sublist); @@ -104,9 +120,15 @@ static void ip6_list_rcv_finish(struct net *net, struct sock *sk, skb = l3mdev_ip6_rcv(skb); if (!skb) continue; - ip6_rcv_finish_core(net, sk, skb); + + if (ip6_can_use_hint(skb, hint)) + skb_dst_copy(skb, hint); + else + ip6_rcv_finish_core(net, sk, skb); dst = skb_dst(skb); if (curr_dst != dst) { + hint = ip6_extract_route_hint(net, skb); + /* dispatch old sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv_finish(&sublist); @@ -223,6 +245,16 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, if (ipv6_addr_is_multicast(&hdr->saddr)) goto err; + /* While RFC4291 is not explicit about v4mapped addresses + * in IPv6 headers, it seems clear linux dual-stack + * model can not deal properly with these. + * Security models could be fooled by ::ffff:127.0.0.1 for example. + * + * https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02 + */ + if (ipv6_addr_v4mapped(&hdr->saddr)) + goto err; + skb->transport_header = skb->network_header + sizeof(*hdr); IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); @@ -315,7 +347,8 @@ void ipv6_list_rcv(struct list_head *head, struct packet_type *pt, list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ - ip6_sublist_rcv(&sublist, curr_dev, curr_net); + if (!list_empty(&sublist)) + ip6_sublist_rcv(&sublist, curr_dev, curr_net); } INDIRECT_CALLABLE_DECLARE(int udpv6_rcv(struct sk_buff *)); @@ -371,7 +404,7 @@ resubmit_final: /* Free reference early: we don't need it any more, and it may hold ip_conntrack module loaded indefinitely. */ - nf_reset(skb); + nf_reset_ct(skb); skb_postpull_rcsum(skb, skb_network_header(skb), skb_network_header_len(skb)); |