linux/net/ipv6/netfilter.c

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/*
* IPv6 specific functions of netfilter core
*
* Rusty Russell (C) 2000 -- This code is GPL.
* Patrick McHardy (C) 2006-2012
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/ipv6.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <linux/export.h>
netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6 Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812: [ ip6tables -m addrtype ] When I tried to use in the nat/PREROUTING it messes up the routing cache even if the rule didn't matched at all. [..] If I remove the --limit-iface-in from the non-working scenario, so just use the -m addrtype --dst-type LOCAL it works! This happens when LOCAL type matching is requested with --limit-iface-in, and the default ipv6 route is via the interface the packet we test arrived on. Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation creates an unwanted cached entry, and the packet won't make it to the real/expected destination. Silently ignoring --limit-iface-in makes the routing work but it breaks rule matching (--dst-type LOCAL with limit-iface-in is supposed to only match if the dst address is configured on the incoming interface; without --limit-iface-in it will match if the address is reachable via lo). The test should call ipv6_chk_addr() instead. However, this would add a link-time dependency on ipv6. There are two possible solutions: 1) Revert the commit that moved ipt_addrtype to xt_addrtype, and put ipv6 specific code into ip6t_addrtype. 2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions. While the former might seem preferable, Pablo pointed out that there are more xt modules with link-time dependeny issues regarding ipv6, so lets go for 2). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-17 03:56:10 +00:00
#include <net/addrconf.h>
#include <net/dst.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
#include <net/netfilter/nf_queue.h>
#include <net/netfilter/nf_conntrack_bridge.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
#include "../bridge/br_private.h"
netfilter: use actual socket sk rather than skb sk when routing harder If netfilter changes the packet mark when mangling, the packet is rerouted using the route_me_harder set of functions. Prior to this commit, there's one big difference between route_me_harder and the ordinary initial routing functions, described in the comment above __ip_queue_xmit(): /* Note: skb->sk can be different from sk, in case of tunnels */ int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, That function goes on to correctly make use of sk->sk_bound_dev_if, rather than skb->sk->sk_bound_dev_if. And indeed the comment is true: a tunnel will receive a packet in ndo_start_xmit with an initial skb->sk. It will make some transformations to that packet, and then it will send the encapsulated packet out of a *new* socket. That new socket will basically always have a different sk_bound_dev_if (otherwise there'd be a routing loop). So for the purposes of routing the encapsulated packet, the routing information as it pertains to the socket should come from that socket's sk, rather than the packet's original skb->sk. For that reason __ip_queue_xmit() and related functions all do the right thing. One might argue that all tunnels should just call skb_orphan(skb) before transmitting the encapsulated packet into the new socket. But tunnels do *not* do this -- and this is wisely avoided in skb_scrub_packet() too -- because features like TSQ rely on skb->destructor() being called when that buffer space is truely available again. Calling skb_orphan(skb) too early would result in buffers filling up unnecessarily and accounting info being all wrong. Instead, additional routing must take into account the new sk, just as __ip_queue_xmit() notes. So, this commit addresses the problem by fishing the correct sk out of state->sk -- it's already set properly in the call to nf_hook() in __ip_local_out(), which receives the sk as part of its normal functionality. So we make sure to plumb state->sk through the various route_me_harder functions, and then make correct use of it following the example of __ip_queue_xmit(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-29 02:56:06 +00:00
int ip6_route_me_harder(struct net *net, struct sock *sk_partial, struct sk_buff *skb)
{
const struct ipv6hdr *iph = ipv6_hdr(skb);
netfilter: use actual socket sk rather than skb sk when routing harder If netfilter changes the packet mark when mangling, the packet is rerouted using the route_me_harder set of functions. Prior to this commit, there's one big difference between route_me_harder and the ordinary initial routing functions, described in the comment above __ip_queue_xmit(): /* Note: skb->sk can be different from sk, in case of tunnels */ int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, That function goes on to correctly make use of sk->sk_bound_dev_if, rather than skb->sk->sk_bound_dev_if. And indeed the comment is true: a tunnel will receive a packet in ndo_start_xmit with an initial skb->sk. It will make some transformations to that packet, and then it will send the encapsulated packet out of a *new* socket. That new socket will basically always have a different sk_bound_dev_if (otherwise there'd be a routing loop). So for the purposes of routing the encapsulated packet, the routing information as it pertains to the socket should come from that socket's sk, rather than the packet's original skb->sk. For that reason __ip_queue_xmit() and related functions all do the right thing. One might argue that all tunnels should just call skb_orphan(skb) before transmitting the encapsulated packet into the new socket. But tunnels do *not* do this -- and this is wisely avoided in skb_scrub_packet() too -- because features like TSQ rely on skb->destructor() being called when that buffer space is truely available again. Calling skb_orphan(skb) too early would result in buffers filling up unnecessarily and accounting info being all wrong. Instead, additional routing must take into account the new sk, just as __ip_queue_xmit() notes. So, this commit addresses the problem by fishing the correct sk out of state->sk -- it's already set properly in the call to nf_hook() in __ip_local_out(), which receives the sk as part of its normal functionality. So we make sure to plumb state->sk through the various route_me_harder functions, and then make correct use of it following the example of __ip_queue_xmit(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-29 02:56:06 +00:00
struct sock *sk = sk_to_full_sk(sk_partial);
struct flow_keys flkeys;
unsigned int hh_len;
struct dst_entry *dst;
int strict = (ipv6_addr_type(&iph->daddr) &
(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
struct flowi6 fl6 = {
.flowi6_oif = sk && sk->sk_bound_dev_if ? sk->sk_bound_dev_if :
strict ? skb_dst(skb)->dev->ifindex : 0,
.flowi6_mark = skb->mark,
.flowi6_uid = sock_net_uid(net, sk),
.daddr = iph->daddr,
.saddr = iph->saddr,
};
int err;
fib6_rules_early_flow_dissect(net, skb, &fl6, &flkeys);
dst = ip6_route_output(net, sk, &fl6);
err = dst->error;
if (err) {
IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
net_dbg_ratelimited("ip6_route_me_harder: No more route\n");
dst_release(dst);
return err;
}
/* Drop old route. */
skb_dst_drop(skb);
skb_dst_set(skb, dst);
#ifdef CONFIG_XFRM
if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) {
skb_dst_set(skb, NULL);
dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
if (IS_ERR(dst))
return PTR_ERR(dst);
skb_dst_set(skb, dst);
}
#endif
/* Change in oif may mean change in hh_len. */
hh_len = skb_dst(skb)->dev->hard_header_len;
if (skb_headroom(skb) < hh_len &&
pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)),
0, GFP_ATOMIC))
return -ENOMEM;
return 0;
}
EXPORT_SYMBOL(ip6_route_me_harder);
static int nf_ip6_reroute(struct sk_buff *skb,
const struct nf_queue_entry *entry)
{
struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
if (entry->state.hook == NF_INET_LOCAL_OUT) {
const struct ipv6hdr *iph = ipv6_hdr(skb);
if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
!ipv6_addr_equal(&iph->saddr, &rt_info->saddr) ||
skb->mark != rt_info->mark)
netfilter: use actual socket sk rather than skb sk when routing harder If netfilter changes the packet mark when mangling, the packet is rerouted using the route_me_harder set of functions. Prior to this commit, there's one big difference between route_me_harder and the ordinary initial routing functions, described in the comment above __ip_queue_xmit(): /* Note: skb->sk can be different from sk, in case of tunnels */ int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, That function goes on to correctly make use of sk->sk_bound_dev_if, rather than skb->sk->sk_bound_dev_if. And indeed the comment is true: a tunnel will receive a packet in ndo_start_xmit with an initial skb->sk. It will make some transformations to that packet, and then it will send the encapsulated packet out of a *new* socket. That new socket will basically always have a different sk_bound_dev_if (otherwise there'd be a routing loop). So for the purposes of routing the encapsulated packet, the routing information as it pertains to the socket should come from that socket's sk, rather than the packet's original skb->sk. For that reason __ip_queue_xmit() and related functions all do the right thing. One might argue that all tunnels should just call skb_orphan(skb) before transmitting the encapsulated packet into the new socket. But tunnels do *not* do this -- and this is wisely avoided in skb_scrub_packet() too -- because features like TSQ rely on skb->destructor() being called when that buffer space is truely available again. Calling skb_orphan(skb) too early would result in buffers filling up unnecessarily and accounting info being all wrong. Instead, additional routing must take into account the new sk, just as __ip_queue_xmit() notes. So, this commit addresses the problem by fishing the correct sk out of state->sk -- it's already set properly in the call to nf_hook() in __ip_local_out(), which receives the sk as part of its normal functionality. So we make sure to plumb state->sk through the various route_me_harder functions, and then make correct use of it following the example of __ip_queue_xmit(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-29 02:56:06 +00:00
return ip6_route_me_harder(entry->state.net, entry->state.sk, skb);
}
return 0;
}
int __nf_ip6_route(struct net *net, struct dst_entry **dst,
struct flowi *fl, bool strict)
{
static const struct ipv6_pinfo fake_pinfo;
static const struct inet_sock fake_sk = {
/* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */
.sk.sk_bound_dev_if = 1,
.pinet6 = (struct ipv6_pinfo *) &fake_pinfo,
};
const void *sk = strict ? &fake_sk : NULL;
struct dst_entry *result;
int err;
result = ip6_route_output(net, sk, &fl->u.ip6);
err = result->error;
if (err)
dst_release(result);
else
*dst = result;
return err;
}
EXPORT_SYMBOL_GPL(__nf_ip6_route);
int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
struct nf_bridge_frag_data *data,
int (*output)(struct net *, struct sock *sk,
const struct nf_bridge_frag_data *data,
struct sk_buff *))
{
int frag_max_size = BR_INPUT_SKB_CB(skb)->frag_max_size;
ktime_t tstamp = skb->tstamp;
struct ip6_frag_state state;
u8 *prevhdr, nexthdr = 0;
unsigned int mtu, hlen;
int hroom, err = 0;
__be32 frag_id;
err = ip6_find_1stfragopt(skb, &prevhdr);
if (err < 0)
goto blackhole;
hlen = err;
nexthdr = *prevhdr;
mtu = skb->dev->mtu;
if (frag_max_size > mtu ||
frag_max_size < IPV6_MIN_MTU)
goto blackhole;
mtu = frag_max_size;
if (mtu < hlen + sizeof(struct frag_hdr) + 8)
goto blackhole;
mtu -= hlen + sizeof(struct frag_hdr);
frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
&ipv6_hdr(skb)->saddr);
if (skb->ip_summed == CHECKSUM_PARTIAL &&
(err = skb_checksum_help(skb)))
goto blackhole;
hroom = LL_RESERVED_SPACE(skb->dev);
if (skb_has_frag_list(skb)) {
unsigned int first_len = skb_pagelen(skb);
struct ip6_fraglist_iter iter;
struct sk_buff *frag2;
if (first_len - hlen > mtu ||
skb_headroom(skb) < (hroom + sizeof(struct frag_hdr)))
goto blackhole;
if (skb_cloned(skb))
goto slow_path;
skb_walk_frags(skb, frag2) {
if (frag2->len > mtu ||
skb_headroom(frag2) < (hlen + hroom + sizeof(struct frag_hdr)))
goto blackhole;
/* Partially cloned skb? */
if (skb_shared(frag2))
goto slow_path;
}
err = ip6_fraglist_init(skb, hlen, prevhdr, nexthdr, frag_id,
&iter);
if (err < 0)
goto blackhole;
for (;;) {
/* Prepare header of the next frame,
* before previous one went down.
*/
if (iter.frag)
ip6_fraglist_prepare(skb, &iter);
skb->tstamp = tstamp;
err = output(net, sk, data, skb);
if (err || !iter.frag)
break;
skb = ip6_fraglist_next(&iter);
}
kfree(iter.tmp_hdr);
if (!err)
return 0;
net: fix use-after-free in kfree_skb_list syzbot reported nasty use-after-free [1] Lets remove frag_list field from structs ip_fraglist_iter and ip6_fraglist_iter. This seens not needed anyway. [1] : BUG: KASAN: use-after-free in kfree_skb_list+0x5d/0x60 net/core/skbuff.c:706 Read of size 8 at addr ffff888085a3cbc0 by task syz-executor303/8947 CPU: 0 PID: 8947 Comm: syz-executor303 Not tainted 5.2.0-rc2+ #12 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 kfree_skb_list+0x5d/0x60 net/core/skbuff.c:706 ip6_fragment+0x1ef4/0x2680 net/ipv6/ip6_output.c:882 __ip6_finish_output+0x577/0xaa0 net/ipv6/ip6_output.c:144 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:156 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:179 dst_output include/net/dst.h:433 [inline] ip6_local_out+0xbb/0x1b0 net/ipv6/output_core.c:179 ip6_send_skb+0xbb/0x350 net/ipv6/ip6_output.c:1796 ip6_push_pending_frames+0xc8/0xf0 net/ipv6/ip6_output.c:1816 rawv6_push_pending_frames net/ipv6/raw.c:617 [inline] rawv6_sendmsg+0x2993/0x35e0 net/ipv6/raw.c:947 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:802 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:671 ___sys_sendmsg+0x803/0x920 net/socket.c:2292 __sys_sendmsg+0x105/0x1d0 net/socket.c:2330 __do_sys_sendmsg net/socket.c:2339 [inline] __se_sys_sendmsg net/socket.c:2337 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2337 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x44add9 Code: e8 7c e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 1b 05 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f826f33bce8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000006e7a18 RCX: 000000000044add9 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000005 RBP: 00000000006e7a10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e7a1c R13: 00007ffcec4f7ebf R14: 00007f826f33c9c0 R15: 20c49ba5e353f7cf Allocated by task 8947: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc_node mm/slab.c:3269 [inline] kmem_cache_alloc_node+0x131/0x710 mm/slab.c:3579 __alloc_skb+0xd5/0x5e0 net/core/skbuff.c:199 alloc_skb include/linux/skbuff.h:1058 [inline] __ip6_append_data.isra.0+0x2a24/0x3640 net/ipv6/ip6_output.c:1519 ip6_append_data+0x1e5/0x320 net/ipv6/ip6_output.c:1688 rawv6_sendmsg+0x1467/0x35e0 net/ipv6/raw.c:940 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:802 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:671 ___sys_sendmsg+0x803/0x920 net/socket.c:2292 __sys_sendmsg+0x105/0x1d0 net/socket.c:2330 __do_sys_sendmsg net/socket.c:2339 [inline] __se_sys_sendmsg net/socket.c:2337 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2337 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8947: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3698 kfree_skbmem net/core/skbuff.c:625 [inline] kfree_skbmem+0xc5/0x150 net/core/skbuff.c:619 __kfree_skb net/core/skbuff.c:682 [inline] kfree_skb net/core/skbuff.c:699 [inline] kfree_skb+0xf0/0x390 net/core/skbuff.c:693 kfree_skb_list+0x44/0x60 net/core/skbuff.c:708 __dev_xmit_skb net/core/dev.c:3551 [inline] __dev_queue_xmit+0x3034/0x36b0 net/core/dev.c:3850 dev_queue_xmit+0x18/0x20 net/core/dev.c:3914 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1532 neigh_output include/net/neighbour.h:511 [inline] ip6_finish_output2+0x1034/0x2550 net/ipv6/ip6_output.c:120 ip6_fragment+0x1ebb/0x2680 net/ipv6/ip6_output.c:863 __ip6_finish_output+0x577/0xaa0 net/ipv6/ip6_output.c:144 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:156 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x235/0x7f0 net/ipv6/ip6_output.c:179 dst_output include/net/dst.h:433 [inline] ip6_local_out+0xbb/0x1b0 net/ipv6/output_core.c:179 ip6_send_skb+0xbb/0x350 net/ipv6/ip6_output.c:1796 ip6_push_pending_frames+0xc8/0xf0 net/ipv6/ip6_output.c:1816 rawv6_push_pending_frames net/ipv6/raw.c:617 [inline] rawv6_sendmsg+0x2993/0x35e0 net/ipv6/raw.c:947 inet_sendmsg+0x141/0x5d0 net/ipv4/af_inet.c:802 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:671 ___sys_sendmsg+0x803/0x920 net/socket.c:2292 __sys_sendmsg+0x105/0x1d0 net/socket.c:2330 __do_sys_sendmsg net/socket.c:2339 [inline] __se_sys_sendmsg net/socket.c:2337 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2337 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888085a3cbc0 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 0 bytes inside of 224-byte region [ffff888085a3cbc0, ffff888085a3cca0) The buggy address belongs to the page: page:ffffea0002168f00 refcount:1 mapcount:0 mapping:ffff88821b6f63c0 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00027bbf88 ffffea0002105b88 ffff88821b6f63c0 raw: 0000000000000000 ffff888085a3c080 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888085a3ca80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888085a3cb00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff888085a3cb80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff888085a3cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888085a3cc80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc Fixes: 0feca6190f88 ("net: ipv6: add skbuff fraglist splitter") Fixes: c8b17be0b7a4 ("net: ipv4: add skbuff fraglist splitter") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-02 18:24:18 +00:00
kfree_skb_list(iter.frag);
return err;
}
slow_path:
/* This is a linearized skbuff, the original geometry is lost for us.
* This may also be a clone skbuff, we could preserve the geometry for
* the copies but probably not worth the effort.
*/
ip6_frag_init(skb, hlen, mtu, skb->dev->needed_tailroom,
LL_RESERVED_SPACE(skb->dev), prevhdr, nexthdr, frag_id,
&state);
while (state.left > 0) {
struct sk_buff *skb2;
skb2 = ip6_frag_next(skb, &state);
if (IS_ERR(skb2)) {
err = PTR_ERR(skb2);
goto blackhole;
}
skb2->tstamp = tstamp;
err = output(net, sk, data, skb2);
if (err)
goto blackhole;
}
consume_skb(skb);
return err;
blackhole:
kfree_skb(skb);
return 0;
}
EXPORT_SYMBOL_GPL(br_ip6_fragment);
netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6 Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812: [ ip6tables -m addrtype ] When I tried to use in the nat/PREROUTING it messes up the routing cache even if the rule didn't matched at all. [..] If I remove the --limit-iface-in from the non-working scenario, so just use the -m addrtype --dst-type LOCAL it works! This happens when LOCAL type matching is requested with --limit-iface-in, and the default ipv6 route is via the interface the packet we test arrived on. Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation creates an unwanted cached entry, and the packet won't make it to the real/expected destination. Silently ignoring --limit-iface-in makes the routing work but it breaks rule matching (--dst-type LOCAL with limit-iface-in is supposed to only match if the dst address is configured on the incoming interface; without --limit-iface-in it will match if the address is reachable via lo). The test should call ipv6_chk_addr() instead. However, this would add a link-time dependency on ipv6. There are two possible solutions: 1) Revert the commit that moved ipt_addrtype to xt_addrtype, and put ipv6 specific code into ip6t_addrtype. 2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions. While the former might seem preferable, Pablo pointed out that there are more xt modules with link-time dependeny issues regarding ipv6, so lets go for 2). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-17 03:56:10 +00:00
static const struct nf_ipv6_ops ipv6ops = {
#if IS_MODULE(CONFIG_IPV6)
.chk_addr = ipv6_chk_addr,
.route_me_harder = ip6_route_me_harder,
.dev_get_saddr = ipv6_dev_get_saddr,
.route = __nf_ip6_route,
#if IS_ENABLED(CONFIG_SYN_COOKIES)
.cookie_init_sequence = __cookie_v6_init_sequence,
.cookie_v6_check = __cookie_v6_check,
#endif
#endif
.route_input = ip6_route_input,
.fragment = ip6_fragment,
.reroute = nf_ip6_reroute,
#if IS_MODULE(CONFIG_IPV6)
.br_fragment = br_ip6_fragment,
#endif
netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6 Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812: [ ip6tables -m addrtype ] When I tried to use in the nat/PREROUTING it messes up the routing cache even if the rule didn't matched at all. [..] If I remove the --limit-iface-in from the non-working scenario, so just use the -m addrtype --dst-type LOCAL it works! This happens when LOCAL type matching is requested with --limit-iface-in, and the default ipv6 route is via the interface the packet we test arrived on. Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation creates an unwanted cached entry, and the packet won't make it to the real/expected destination. Silently ignoring --limit-iface-in makes the routing work but it breaks rule matching (--dst-type LOCAL with limit-iface-in is supposed to only match if the dst address is configured on the incoming interface; without --limit-iface-in it will match if the address is reachable via lo). The test should call ipv6_chk_addr() instead. However, this would add a link-time dependency on ipv6. There are two possible solutions: 1) Revert the commit that moved ipt_addrtype to xt_addrtype, and put ipv6 specific code into ip6t_addrtype. 2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions. While the former might seem preferable, Pablo pointed out that there are more xt modules with link-time dependeny issues regarding ipv6, so lets go for 2). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-17 03:56:10 +00:00
};
int __init ipv6_netfilter_init(void)
{
netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6 Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812: [ ip6tables -m addrtype ] When I tried to use in the nat/PREROUTING it messes up the routing cache even if the rule didn't matched at all. [..] If I remove the --limit-iface-in from the non-working scenario, so just use the -m addrtype --dst-type LOCAL it works! This happens when LOCAL type matching is requested with --limit-iface-in, and the default ipv6 route is via the interface the packet we test arrived on. Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation creates an unwanted cached entry, and the packet won't make it to the real/expected destination. Silently ignoring --limit-iface-in makes the routing work but it breaks rule matching (--dst-type LOCAL with limit-iface-in is supposed to only match if the dst address is configured on the incoming interface; without --limit-iface-in it will match if the address is reachable via lo). The test should call ipv6_chk_addr() instead. However, this would add a link-time dependency on ipv6. There are two possible solutions: 1) Revert the commit that moved ipt_addrtype to xt_addrtype, and put ipv6 specific code into ip6t_addrtype. 2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions. While the former might seem preferable, Pablo pointed out that there are more xt modules with link-time dependeny issues regarding ipv6, so lets go for 2). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-17 03:56:10 +00:00
RCU_INIT_POINTER(nf_ipv6_ops, &ipv6ops);
return 0;
}
/* This can be called from inet6_init() on errors, so it cannot
* be marked __exit. -DaveM
*/
void ipv6_netfilter_fini(void)
{
netfilter: add nf_ipv6_ops hook to fix xt_addrtype with IPv6 Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812: [ ip6tables -m addrtype ] When I tried to use in the nat/PREROUTING it messes up the routing cache even if the rule didn't matched at all. [..] If I remove the --limit-iface-in from the non-working scenario, so just use the -m addrtype --dst-type LOCAL it works! This happens when LOCAL type matching is requested with --limit-iface-in, and the default ipv6 route is via the interface the packet we test arrived on. Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation creates an unwanted cached entry, and the packet won't make it to the real/expected destination. Silently ignoring --limit-iface-in makes the routing work but it breaks rule matching (--dst-type LOCAL with limit-iface-in is supposed to only match if the dst address is configured on the incoming interface; without --limit-iface-in it will match if the address is reachable via lo). The test should call ipv6_chk_addr() instead. However, this would add a link-time dependency on ipv6. There are two possible solutions: 1) Revert the commit that moved ipt_addrtype to xt_addrtype, and put ipv6 specific code into ip6t_addrtype. 2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions. While the former might seem preferable, Pablo pointed out that there are more xt modules with link-time dependeny issues regarding ipv6, so lets go for 2). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-05-17 03:56:10 +00:00
RCU_INIT_POINTER(nf_ipv6_ops, NULL);
}