diff options
Diffstat (limited to 'net/ipv6/ip6_input.c')
| -rw-r--r-- | net/ipv6/ip6_input.c | 63 |
1 files changed, 51 insertions, 12 deletions
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index c7ed2b6d5a1d..7b089d0ac8cd 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * IPv6 input * Linux INET6 implementation @@ -7,11 +8,6 @@ * Ian P. Morris <I.P.Morris@soton.ac.uk> * * Based in linux/net/ipv4/ip_input.c - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ /* Changes * @@ -29,6 +25,7 @@ #include <linux/icmpv6.h> #include <linux/mroute6.h> #include <linux/slab.h> +#include <linux/indirect_call_wrapper.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv6.h> @@ -47,6 +44,8 @@ #include <net/inet_ecn.h> #include <net/dst_metadata.h> +INDIRECT_CALLABLE_DECLARE(void udp_v6_early_demux(struct sk_buff *)); +INDIRECT_CALLABLE_DECLARE(void tcp_v6_early_demux(struct sk_buff *)); static void ip6_rcv_finish_core(struct net *net, struct sock *sk, struct sk_buff *skb) { @@ -57,7 +56,8 @@ static void ip6_rcv_finish_core(struct net *net, struct sock *sk, ipprot = rcu_dereference(inet6_protos[ipv6_hdr(skb)->nexthdr]); if (ipprot && (edemux = READ_ONCE(ipprot->early_demux))) - edemux(skb); + INDIRECT_CALL_2(edemux, tcp_v6_early_demux, + udp_v6_early_demux, skb); } if (!skb_valid_dst(skb)) ip6_route_input(skb); @@ -80,15 +80,33 @@ static void ip6_sublist_rcv_finish(struct list_head *head) { struct sk_buff *skb, *next; - list_for_each_entry_safe(skb, next, head, list) + list_for_each_entry_safe(skb, next, head, list) { + skb_list_del_init(skb); dst_input(skb); + } +} + +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); @@ -102,9 +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); @@ -221,6 +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); @@ -313,9 +347,13 @@ 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 *)); +INDIRECT_CALLABLE_DECLARE(int tcp_v6_rcv(struct sk_buff *)); + /* * Deliver the packet to the host */ @@ -366,7 +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)); @@ -391,7 +429,8 @@ resubmit_final: !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) goto discard; - ret = ipprot->handler(skb); + ret = INDIRECT_CALL_2(ipprot->handler, tcp_v6_rcv, udpv6_rcv, + skb); if (ret > 0) { if (ipprot->flags & INET6_PROTO_FINAL) { /* Not an extension header, most likely UDP |