summaryrefslogtreecommitdiff
path: root/net/ipv6
AgeCommit message (Collapse)AuthorFilesLines
2024-06-20Merge tag 'nf-24-06-19' of ↵Paolo Abeni1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 fixes the suspicious RCU usage warning that resulted from the recent fix for the race between namespace cleanup and gc in ipset left out checking the pernet exit phase when calling rcu_dereference_protected(), from Jozsef Kadlecsik. Patch #2 fixes incorrect input and output netdevice in SRv6 prerouting hooks, from Jianguo Wu. Patch #3 moves nf_hooks_lwtunnel sysctl toggle to the netfilter core. The connection tracking system is loaded on-demand, this ensures availability of this knob regardless. Patch #4-#5 adds selftests for SRv6 netfilter hooks also from Jianguo Wu. netfilter pull request 24-06-19 * tag 'nf-24-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: selftests: add selftest for the SRv6 End.DX6 behavior with netfilter selftests: add selftest for the SRv6 End.DX4 behavior with netfilter netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors netfilter: ipset: Fix suspicious rcu_dereference_protected() ==================== Link: https://lore.kernel.org/r/20240619170537.2846-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-20ipv6: bring NLM_DONE out to a separate recv() againJakub Kicinski1-1/+2
Commit under Fixes optimized the number of recv() calls needed during RTM_GETROUTE dumps, but we got multiple reports of applications hanging on recv() calls. Applications expect that a route dump will be terminated with a recv() reading an individual NLM_DONE message. Coalescing NLM_DONE is perfectly legal in netlink, but even tho reporters fixed the code in respective projects, chances are it will take time for those applications to get updated. So revert to old behavior (for now)? This is an IPv6 version of commit 460b0d33cf10 ("inet: bring NLM_DONE out to a separate recv() again"). Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com> Link: https://lore.kernel.org/all/CANP3RGc1RG71oPEBXNx_WZFP9AyphJefdO4paczN92n__ds4ow@mail.gmail.com Reported-by: Stefano Brivio <sbrivio@redhat.com> Link: https://lore.kernel.org/all/20240315124808.033ff58d@elisabeth Reported-by: Ilya Maximets <i.maximets@ovn.org> Link: https://lore.kernel.org/all/02b50aae-f0e9-47a4-8365-a977a85975d3@ovn.org Fixes: 5fc68320c1fb ("ipv6: remove RTNL protection from inet6_dump_fib()") Tested-by: Ilya Maximets <i.maximets@ovn.org> Link: https://lore.kernel.org/r/20240618193914.561782-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-19seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 ↵Jianguo Wu1-4/+4
behaviors input_action_end_dx4() and input_action_end_dx6() are called NF_HOOK() for PREROUTING hook, in PREROUTING hook, we should passing a valid indev, and a NULL outdev to NF_HOOK(), otherwise may trigger a NULL pointer dereference, as below: [74830.647293] BUG: kernel NULL pointer dereference, address: 0000000000000090 [74830.655633] #PF: supervisor read access in kernel mode [74830.657888] #PF: error_code(0x0000) - not-present page [74830.659500] PGD 0 P4D 0 [74830.660450] Oops: 0000 [#1] PREEMPT SMP PTI ... [74830.664953] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [74830.666569] RIP: 0010:rpfilter_mt+0x44/0x15e [ipt_rpfilter] ... [74830.689725] Call Trace: [74830.690402] <IRQ> [74830.690953] ? show_trace_log_lvl+0x1c4/0x2df [74830.692020] ? show_trace_log_lvl+0x1c4/0x2df [74830.693095] ? ipt_do_table+0x286/0x710 [ip_tables] [74830.694275] ? __die_body.cold+0x8/0xd [74830.695205] ? page_fault_oops+0xac/0x140 [74830.696244] ? exc_page_fault+0x62/0x150 [74830.697225] ? asm_exc_page_fault+0x22/0x30 [74830.698344] ? rpfilter_mt+0x44/0x15e [ipt_rpfilter] [74830.699540] ipt_do_table+0x286/0x710 [ip_tables] [74830.700758] ? ip6_route_input+0x19d/0x240 [74830.701752] nf_hook_slow+0x3f/0xb0 [74830.702678] input_action_end_dx4+0x19b/0x1e0 [74830.703735] ? input_action_end_t+0xe0/0xe0 [74830.704734] seg6_local_input_core+0x2d/0x60 [74830.705782] lwtunnel_input+0x5b/0xb0 [74830.706690] __netif_receive_skb_one_core+0x63/0xa0 [74830.707825] process_backlog+0x99/0x140 [74830.709538] __napi_poll+0x2c/0x160 [74830.710673] net_rx_action+0x296/0x350 [74830.711860] __do_softirq+0xcb/0x2ac [74830.713049] do_softirq+0x63/0x90 input_action_end_dx4() passing a NULL indev to NF_HOOK(), and finally trigger a NULL dereference in rpfilter_mt()->rpfilter_is_loopback(): static bool rpfilter_is_loopback(const struct sk_buff *skb, const struct net_device *in) { // in is NULL return skb->pkt_type == PACKET_LOOPBACK || in->flags & IFF_LOOPBACK; } Fixes: 7a3f5b0de364 ("netfilter: add netfilter hooks to SRv6 data plane") Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-06-18xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr()Eric Dumazet1-1/+7
ip6_dst_idev() can return NULL, xfrm6_get_saddr() must act accordingly. syzbot reported: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker RIP: 0010:xfrm6_get_saddr+0x93/0x130 net/ipv6/xfrm6_policy.c:64 Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 97 00 00 00 4c 8b ab d8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 00 00 00 4d 8b 6d 00 e8 ca 13 47 01 48 b8 00 RSP: 0018:ffffc90000117378 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: ffff88807b079dc0 RCX: ffffffff89a0d6d7 RDX: 0000000000000000 RSI: ffffffff89a0d6e9 RDI: ffff88807b079e98 RBP: ffff88807ad73248 R08: 0000000000000007 R09: fffffffffffff000 R10: ffff88807b079dc0 R11: 0000000000000007 R12: ffffc90000117480 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4586d00440 CR3: 0000000079042000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> xfrm_get_saddr net/xfrm/xfrm_policy.c:2452 [inline] xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2481 [inline] xfrm_tmpl_resolve+0xa26/0xf10 net/xfrm/xfrm_policy.c:2541 xfrm_resolve_and_create_bundle+0x140/0x2570 net/xfrm/xfrm_policy.c:2835 xfrm_bundle_lookup net/xfrm/xfrm_policy.c:3070 [inline] xfrm_lookup_with_ifid+0x4d1/0x1e60 net/xfrm/xfrm_policy.c:3201 xfrm_lookup net/xfrm/xfrm_policy.c:3298 [inline] xfrm_lookup_route+0x3b/0x200 net/xfrm/xfrm_policy.c:3309 ip6_dst_lookup_flow+0x15c/0x1d0 net/ipv6/ip6_output.c:1256 send6+0x611/0xd20 drivers/net/wireguard/socket.c:139 wg_socket_send_skb_to_peer+0xf9/0x220 drivers/net/wireguard/socket.c:178 wg_socket_send_buffer_to_peer+0x12b/0x190 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation+0x227/0x360 drivers/net/wireguard/send.c:40 wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240615154231.234442-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-18ipv6: prevent possible NULL dereference in rt6_probe()Eric Dumazet1-0/+2
syzbot caught a NULL dereference in rt6_probe() [1] Bail out if __in6_dev_get() returns NULL. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc00000000cb: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000658-0x000000000000065f] CPU: 1 PID: 22444 Comm: syz-executor.0 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 RIP: 0010:rt6_probe net/ipv6/route.c:656 [inline] RIP: 0010:find_match+0x8c4/0xf50 net/ipv6/route.c:758 Code: 14 fd f7 48 8b 85 38 ff ff ff 48 c7 45 b0 00 00 00 00 48 8d b8 5c 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 19 RSP: 0018:ffffc900034af070 EFLAGS: 00010203 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90004521000 RDX: 00000000000000cb RSI: ffffffff8990d0cd RDI: 000000000000065c RBP: ffffc900034af150 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000002 R12: 000000000000000a R13: 1ffff92000695e18 R14: ffff8880244a1d20 R15: 0000000000000000 FS: 00007f4844a5a6c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31b27000 CR3: 000000002d42c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> rt6_nh_find_match+0xfa/0x1a0 net/ipv6/route.c:784 nexthop_for_each_fib6_nh+0x26d/0x4a0 net/ipv4/nexthop.c:1496 __find_rr_leaf+0x6e7/0xe00 net/ipv6/route.c:825 find_rr_leaf net/ipv6/route.c:853 [inline] rt6_select net/ipv6/route.c:897 [inline] fib6_table_lookup+0x57e/0xa30 net/ipv6/route.c:2195 ip6_pol_route+0x1cd/0x1150 net/ipv6/route.c:2231 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x386/0x720 net/ipv6/fib6_rules.c:121 ip6_route_output_flags_noref net/ipv6/route.c:2639 [inline] ip6_route_output_flags+0x1d0/0x640 net/ipv6/route.c:2651 ip6_dst_lookup_tail.constprop.0+0x961/0x1760 net/ipv6/ip6_output.c:1147 ip6_dst_lookup_flow+0x99/0x1d0 net/ipv6/ip6_output.c:1250 rawv6_sendmsg+0xdab/0x4340 net/ipv6/raw.c:898 inet_sendmsg+0x119/0x140 net/ipv4/af_inet.c:853 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x4b8/0x5c0 net/socket.c:1160 new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6b6/0x1140 fs/read_write.c:590 ksys_write+0x1f8/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 52e1635631b3 ("[IPV6]: ROUTE: Add router_probe_interval sysctl.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240615151454.166404-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-18ipv6: prevent possible NULL deref in fib6_nh_init()Eric Dumazet1-1/+1
syzbot reminds us that in6_dev_get() can return NULL. fib6_nh_init() ip6_validate_gw( &idev ) ip6_route_check_nh( idev ) *idev = in6_dev_get(dev); // can be NULL Oops: general protection fault, probably for non-canonical address 0xdffffc00000000bc: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x00000000000005e0-0x00000000000005e7] CPU: 0 PID: 11237 Comm: syz-executor.3 Not tainted 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:fib6_nh_init+0x640/0x2160 net/ipv6/route.c:3606 Code: 00 00 fc ff df 4c 8b 64 24 58 48 8b 44 24 28 4c 8b 74 24 30 48 89 c1 48 89 44 24 28 48 8d 98 e0 05 00 00 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 b3 17 00 00 8b 1b 31 ff 89 de e8 b8 8b RSP: 0018:ffffc900032775a0 EFLAGS: 00010202 RAX: 00000000000000bc RBX: 00000000000005e0 RCX: 0000000000000000 RDX: 0000000000000010 RSI: ffffc90003277a54 RDI: ffff88802b3a08d8 RBP: ffffc900032778b0 R08: 00000000000002fc R09: 0000000000000000 R10: 00000000000002fc R11: 0000000000000000 R12: ffff88802b3a08b8 R13: 1ffff9200064eec8 R14: ffffc90003277a00 R15: dffffc0000000000 FS: 00007f940feb06c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000245e8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ip6_route_info_create+0x99e/0x12b0 net/ipv6/route.c:3809 ip6_route_add+0x28/0x160 net/ipv6/route.c:3853 ipv6_route_ioctl+0x588/0x870 net/ipv6/route.c:4483 inet6_ioctl+0x21a/0x280 net/ipv6/af_inet6.c:579 sock_do_ioctl+0x158/0x460 net/socket.c:1222 sock_ioctl+0x629/0x8e0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f940f07cea9 Fixes: 428604fb118f ("ipv6: do not set routes if disable_ipv6 has been enabled") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Lorenzo Bianconi <lorenzo@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240614082002.26407-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-13net/ipv6: Fix the RT cache flush via sysctl using a previous delayPetr Pavlu1-2/+2
The net.ipv6.route.flush system parameter takes a value which specifies a delay used during the flush operation for aging exception routes. The written value is however not used in the currently requested flush and instead utilized only in the next one. A problem is that ipv6_sysctl_rtcache_flush() first reads the old value of net->ipv6.sysctl.flush_delay into a local delay variable and then calls proc_dointvec() which actually updates the sysctl based on the provided input. Fix the problem by switching the order of the two operations. Fixes: 4990509f19e8 ("[NETNS][IPV6]: Make sysctls route per namespace.") Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240607112828.30285-1-petr.pavlu@suse.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-11netfilter: Use flowlabel flow key when re-routing mangled packetsFlorian Westphal1-0/+1
'ip6 dscp set $v' in an nftables outpute route chain has no effect. While nftables does detect the dscp change and calls the reroute hook. But ip6_route_me_harder never sets the dscp/flowlabel: flowlabel/dsfield routing rules are ignored and no reroute takes place. Thanks to Yi Chen for an excellent reproducer script that I used to validate this change. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Yi Chen <yiche@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-06-10tcp: fix race in tcp_v6_syn_recv_sock()Eric Dumazet1-1/+2
tcp_v6_syn_recv_sock() calls ip6_dst_store() before inet_sk(newsk)->pinet6 has been set up. This means ip6_dst_store() writes over the parent (listener) np->dst_cookie. This is racy because multiple threads could share the same parent and their final np->dst_cookie could be wrong. Move ip6_dst_store() call after inet_sk(newsk)->pinet6 has been changed and after the copy of parent ipv6_pinfo. Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-06ipv6: fix possible race in __fib6_drop_pcpu_from()Eric Dumazet2-1/+6
syzbot found a race in __fib6_drop_pcpu_from() [1] If compiler reads more than once (*ppcpu_rt), second read could read NULL, if another cpu clears the value in rt6_get_pcpu_route(). Add a READ_ONCE() to prevent this race. Also add rcu_read_lock()/rcu_read_unlock() because we rely on RCU protection while dereferencing pcpu_rt. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097] CPU: 0 PID: 7543 Comm: kworker/u8:17 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: netns cleanup_net RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10a/0x370 net/ipv6/ip6_fib.c:984 Code: f8 48 c1 e8 03 80 3c 28 00 0f 85 16 02 00 00 4d 8b 3f 4d 85 ff 74 31 e8 74 a7 fa f7 49 8d bf 90 00 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 1e 02 00 00 49 8b 87 90 00 00 00 48 8b 0c 24 48 RSP: 0018:ffffc900040df070 EFLAGS: 00010206 RAX: 0000000000000012 RBX: 0000000000000001 RCX: ffffffff89932e16 RDX: ffff888049dd1e00 RSI: ffffffff89932d7c RDI: 0000000000000091 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000007 R10: 0000000000000001 R11: 0000000000000006 R12: ffff88807fa080b8 R13: fffffbfff1a9a07d R14: ffffed100ff41022 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32c26000 CR3: 000000005d56e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __fib6_drop_pcpu_from net/ipv6/ip6_fib.c:966 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1027 [inline] fib6_purge_rt+0x7f2/0x9f0 net/ipv6/ip6_fib.c:1038 fib6_del_route net/ipv6/ip6_fib.c:1998 [inline] fib6_del+0xa70/0x17b0 net/ipv6/ip6_fib.c:2043 fib6_clean_node+0x426/0x5b0 net/ipv6/ip6_fib.c:2205 fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2127 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2175 fib6_clean_tree+0xd7/0x120 net/ipv6/ip6_fib.c:2255 __fib6_clean_all+0x100/0x2d0 net/ipv6/ip6_fib.c:2271 rt6_sync_down_dev net/ipv6/route.c:4906 [inline] rt6_disable_ip+0x7ed/0xa00 net/ipv6/route.c:4911 addrconf_ifdown.isra.0+0x117/0x1b40 net/ipv6/addrconf.c:3855 addrconf_notify+0x223/0x19e0 net/ipv6/addrconf.c:3778 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] dev_close_many+0x333/0x6a0 net/core/dev.c:1585 unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11193 unregister_netdevice_many net/core/dev.c:11276 [inline] default_device_exit_batch+0x85b/0xae0 net/core/dev.c:11759 ops_exit_list+0x128/0x180 net/core/net_namespace.c:178 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Fixes: d52d3997f843 ("ipv6: Create percpu rt6_info") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/r/20240604193549.981839-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-04ila: block BH in ila_output()Eric Dumazet1-1/+6
As explained in commit 1378817486d6 ("tipc: block BH before using dst_cache"), net/core/dst_cache.c helpers need to be called with BH disabled. ila_output() is called from lwtunnel_output() possibly from process context, and under rcu_read_lock(). We might be interrupted by a softirq, re-enter ila_output() and corrupt dst_cache data structures. Fix the race by using local_bh_disable(). Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240531132636.2637995-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-04ipv6: sr: block BH in seg6_output_core() and seg6_input_core()Eric Dumazet1-8/+6
As explained in commit 1378817486d6 ("tipc: block BH before using dst_cache"), net/core/dst_cache.c helpers need to be called with BH disabled. Disabling preemption in seg6_output_core() is not good enough, because seg6_output_core() is called from process context, lwtunnel_output() only uses rcu_read_lock(). We might be interrupted by a softirq, re-enter seg6_output_core() and corrupt dst_cache data structures. Fix the race by using local_bh_disable() instead of preempt_disable(). Apply a similar change in seg6_input_core(). Fixes: fa79581ea66c ("ipv6: sr: fix several BUGs when preemption is enabled") Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Lebrun <dlebrun@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240531132636.2637995-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-04net: ipv6: rpl_iptunnel: block BH in rpl_output() and rpl_input()Eric Dumazet1-8/+6
As explained in commit 1378817486d6 ("tipc: block BH before using dst_cache"), net/core/dst_cache.c helpers need to be called with BH disabled. Disabling preemption in rpl_output() is not good enough, because rpl_output() is called from process context, lwtunnel_output() only uses rcu_read_lock(). We might be interrupted by a softirq, re-enter rpl_output() and corrupt dst_cache data structures. Fix the race by using local_bh_disable() instead of preempt_disable(). Apply a similar change in rpl_input(). Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Alexander Aring <aahringo@redhat.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240531132636.2637995-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-04ipv6: ioam: block BH from ioam6_output()Eric Dumazet1-4/+4
As explained in commit 1378817486d6 ("tipc: block BH before using dst_cache"), net/core/dst_cache.c helpers need to be called with BH disabled. Disabling preemption in ioam6_output() is not good enough, because ioam6_output() is called from process context, lwtunnel_output() only uses rcu_read_lock(). We might be interrupted by a softirq, re-enter ioam6_output() and corrupt dst_cache data structures. Fix the race by using local_bh_disable() instead of preempt_disable(). Fixes: 8cb3bf8bff3c ("ipv6: ioam: Add support for the ip6ip6 encapsulation") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Justin Iurman <justin.iurman@uliege.be> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20240531132636.2637995-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-30net: fix __dst_negative_advice() raceEric Dumazet1-14/+15
__dst_negative_advice() does not enforce proper RCU rules when sk->dst_cache must be cleared, leading to possible UAF. RCU rules are that we must first clear sk->sk_dst_cache, then call dst_release(old_dst). Note that sk_dst_reset(sk) is implementing this protocol correctly, while __dst_negative_advice() uses the wrong order. Given that ip6_negative_advice() has special logic against RTF_CACHE, this means each of the three ->negative_advice() existing methods must perform the sk_dst_reset() themselves. Note the check against NULL dst is centralized in __dst_negative_advice(), there is no need to duplicate it in various callbacks. Many thanks to Clement Lecigne for tracking this issue. This old bug became visible after the blamed commit, using UDP sockets. Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets") Reported-by: Clement Lecigne <clecigne@google.com> Diagnosed-by: Clement Lecigne <clecigne@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <tom@herbertland.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-28tcp: reduce accepted window in NEW_SYN_RECV stateEric Dumazet1-6/+1
Jason commit made checks against ACK sequence less strict and can be exploited by attackers to establish spoofed flows with less probes. Innocent users might use tcp_rmem[1] == 1,000,000,000, or something more reasonable. An attacker can use a regular TCP connection to learn the server initial tp->rcv_wnd, and use it to optimize the attack. If we make sure that only the announced window (smaller than 65535) is used for ACK validation, we force an attacker to use 65537 packets to complete the 3WHS (assuming server ISN is unknown) Fixes: 378979e94e95 ("tcp: remove 64 KByte limit for initial tp->rcv_wnd value") Link: https://datatracker.ietf.org/meeting/119/materials/slides-119-tcpm-ghost-acks-00 Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://lore.kernel.org/r/20240523130528.60376-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-28net: gro: initialize network_offset in network layerWillem de Bruijn1-1/+1
Syzkaller was able to trigger kernel BUG at net/core/gro.c:424 ! RIP: 0010:gro_pull_from_frag0 net/core/gro.c:424 [inline] RIP: 0010:gro_try_pull_from_frag0 net/core/gro.c:446 [inline] RIP: 0010:dev_gro_receive+0x242f/0x24b0 net/core/gro.c:571 Due to using an incorrect NAPI_GRO_CB(skb)->network_offset. The referenced commit sets this offset to 0 in skb_gro_reset_offset. That matches the expected case in dev_gro_receive: pp = INDIRECT_CALL_INET(ptype->callbacks.gro_receive, ipv6_gro_receive, inet_gro_receive, &gro_list->list, skb); But syzkaller injected an skb with protocol ETH_P_TEB into an ip6gre device (by writing the IP6GRE encapsulated version to a TAP device). The result was a first call to eth_gro_receive, and thus an extra ETH_HLEN in network_offset that should not be there. First issue hit is when computing offset from network header in ipv6_gro_pull_exthdrs. Initialize both offsets in the network layer gro_receive. This pairs with all reads in gro_receive, which use skb_gro_receive_network_offset(). Fixes: 186b1ea73ad8 ("net: gro: use cb instead of skb->network_header") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Willem de Bruijn <willemb@google.com> CC: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240523141434.1752483-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-21ipv6: sr: fix memleak in seg6_hmac_init_algoHangbin Liu1-14/+28
seg6_hmac_init_algo returns without cleaning up the previous allocations if one fails, so it's going to leak all that memory and the crypto tfms. Update seg6_hmac_exit to only free the memory when allocated, so we can reuse the code directly. Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support") Reported-by: Sabrina Dubroca <sd@queasysnail.net> Closes: https://lore.kernel.org/netdev/Zj3bh-gE7eT6V6aH@hog/ Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Link: https://lore.kernel.org/r/20240517005435.2600277-1-liuhangbin@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-20ipv6: sr: fix missing sk_buff release in seg6_input_coreAndrea Mayer1-5/+6
The seg6_input() function is responsible for adding the SRH into a packet, delegating the operation to the seg6_input_core(). This function uses the skb_cow_head() to ensure that there is sufficient headroom in the sk_buff for accommodating the link-layer header. In the event that the skb_cow_header() function fails, the seg6_input_core() catches the error but it does not release the sk_buff, which will result in a memory leak. This issue was introduced in commit af3b5158b89d ("ipv6: sr: fix BUG due to headroom too small after SRH push") and persists even after commit 7a3f5b0de364 ("netfilter: add netfilter hooks to SRv6 data plane"), where the entire seg6_input() code was refactored to deal with netfilter hooks. The proposed patch addresses the identified memory leak by requiring the seg6_input_core() function to release the sk_buff in the event that skb_cow_head() fails. Fixes: af3b5158b89d ("ipv6: sr: fix BUG due to headroom too small after SRH push") Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-17net/ipv6: Fix route deleting failure when metric equals 0xu xin1-1/+4
Problem ========= After commit 67f695134703 ("ipv6: Move setting default metric for routes"), we noticed that the logic of assigning the default value of fc_metirc changed in the ioctl process. That is, when users use ioctl(fd, SIOCADDRT, rt) with a non-zero metric to add a route, then they may fail to delete a route with passing in a metric value of 0 to the kernel by ioctl(fd, SIOCDELRT, rt). But iproute can succeed in deleting it. As a reference, when using iproute tools by netlink to delete routes with a metric parameter equals 0, like the command as follows: ip -6 route del fe80::/64 via fe81::5054:ff:fe11:3451 dev eth0 metric 0 the user can still succeed in deleting the route entry with the smallest metric. Root Reason =========== After commit 67f695134703 ("ipv6: Move setting default metric for routes"), When ioctl() pass in SIOCDELRT with a zero metric, rtmsg_to_fib6_config() will set a defalut value (1024) to cfg->fc_metric in kernel, and in ip6_route_del() and the line 4074 at net/ipv3/route.c, it will check by if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric) continue; and the condition is true and skip the later procedure (deleting route) because cfg->fc_metric != rt->fib6_metric. But before that commit, cfg->fc_metric is still zero there, so the condition is false and it will do the following procedure (deleting). Solution ======== In order to keep a consistent behaviour across netlink() and ioctl(), we should allow to delete a route with a metric value of 0. So we only do the default setting of fc_metric in route adding. CC: stable@vger.kernel.org # 5.4+ Fixes: 67f695134703 ("ipv6: Move setting default metric for routes") Co-developed-by: Fan Yu <fan.yu9@zte.com.cn> Signed-off-by: Fan Yu <fan.yu9@zte.com.cn> Signed-off-by: xu xin <xu.xin16@zte.com.cn> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240514201102055dD2Ba45qKbLlUMxu_DTHP@zte.com.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+4
Merge in late fixes to prepare for the 6.10 net-next PR. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-14tcp: rstreason: handle timewait cases in the receive pathJason Xing1-1/+1
There are two possible cases where TCP layer can send an RST. Since they happen in the same place, I think using one independent reason is enough to identify this special situation. Signed-off-by: Jason Xing <kernelxing@tencent.com> Link: https://lore.kernel.org/r/20240510122502.27850-5-kerneljasonxing@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-14net: gro: move L3 flush checks to tcp_gro_receive and udp_gro_receive_segmentRichard Gobert1-11/+0
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are used in all merging UDP and TCP flows. These checks need to be done only once and only against the found p skb, since they only affect flush and not same_flow. This patch leverages correct network header offsets from the cb for both outer and inner network headers - allowing these checks to be done only once, in tcp_gro_receive and udp_gro_receive_segment. As a result, NAPI_GRO_CB(p)->flush is not used at all. In addition, flush_id checks are more declarative and contained in inet_gro_flush, thus removing the need for flush_id in napi_gro_cb. This results in less parsing code for non-loop flush tests for TCP and UDP flows. To make sure results are not within noise range - I've made netfilter drop all TCP packets, and measured CPU performance in GRO (in this case GRO is responsible for about 50% of the CPU utilization). perf top while replaying 64 parallel IP/TCP streams merging in GRO: (gro_receive_network_flush is compiled inline to tcp_gro_receive) net-next: 6.94% [kernel] [k] inet_gro_receive 3.02% [kernel] [k] tcp_gro_receive patch applied: 4.27% [kernel] [k] tcp_gro_receive 4.22% [kernel] [k] inet_gro_receive perf top while replaying 64 parallel IP/IP/TCP streams merging in GRO (same results for any encapsulation, in this case inet_gro_receive is top offender in net-next) net-next: 10.09% [kernel] [k] inet_gro_receive 2.08% [kernel] [k] tcp_gro_receive patch applied: 6.97% [kernel] [k] inet_gro_receive 3.68% [kernel] [k] tcp_gro_receive Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240509190819.2985-3-richardbgobert@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-14net: gro: use cb instead of skb->network_headerRichard Gobert2-4/+4
This patch converts references of skb->network_header to napi_gro_cb's network_offset and inner_network_offset. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240509190819.2985-2-richardbgobert@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13Merge tag 'nf-next-24-05-12' of ↵Jakub Kicinski1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next: Patch #1 skips transaction if object type provides no .update interface. Patch #2 skips NETDEV_CHANGENAME which is unused. Patch #3 enables conntrack to handle Multicast Router Advertisements and Multicast Router Solicitations from the Multicast Router Discovery protocol (RFC4286) as untracked opposed to invalid packets. From Linus Luessing. Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of dropping them, from Jason Xing. Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0, also from Jason. Patch #6 removes reference in netfilter's sysctl documentation on pickup entries which were already removed by Florian Westphal. Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which allows to evict entries from the conntrack table, also from Florian. Patches #8 to #16 updates nf_tables pipapo set backend to allocate the datastructure copy on-demand from preparation phase, to better deal with OOM situations where .commit step is too late to fail. Series from Florian Westphal. Patch #17 adds a selftest with packetdrill to cover conntrack TCP state transitions, also from Florian. Patch #18 use GFP_KERNEL to clone elements from control plane to avoid quick atomic reserves exhaustion with large sets, reporter refers to million entries magnitude. * tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next: netfilter: nf_tables: allow clone callbacks to sleep selftests: netfilter: add packetdrill based conntrack tests netfilter: nft_set_pipapo: remove dirty flag netfilter: nft_set_pipapo: move cloning of match info to insert/removal path netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone netfilter: nft_set_pipapo: merge deactivate helper into caller netfilter: nft_set_pipapo: prepare walk function for on-demand clone netfilter: nft_set_pipapo: prepare destroy function for on-demand clone netfilter: nft_set_pipapo: make pipapo_clone helper return NULL netfilter: nft_set_pipapo: move prove_locking helper around netfilter: conntrack: remove flowtable early-drop test netfilter: conntrack: documentation: remove reference to non-existent sysctl netfilter: use NF_DROP instead of -NF_DROP netfilter: conntrack: dccp: try not to drop skb in conntrack netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler netfilter: nf_tables: skip transaction if update object is not implemented ==================== Link: https://lore.kernel.org/r/20240512161436.168973-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-11ipv6: sr: fix invalid unregister error pathHangbin Liu1-0/+2
The error path of seg6_init() is wrong in case CONFIG_IPV6_SEG6_LWTUNNEL is not defined. In that case if seg6_hmac_init() fails, the genl_unregister_family() isn't called. This issue exist since commit 46738b1317e1 ("ipv6: sr: add option to control lwtunnel support"), and commit 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") replaced unregister_pernet_subsys() with genl_unregister_family() in this error path. Fixes: 46738b1317e1 ("ipv6: sr: add option to control lwtunnel support") Reported-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240509131812.1662197-4-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-11ipv6: sr: fix incorrect unregister orderHangbin Liu1-1/+1
Commit 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") changed the register order in seg6_init(). But the unregister order in seg6_exit() is not updated. Fixes: 5559cea2d5aa ("ipv6: sr: fix possible use-after-free and null-ptr-deref") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240509131812.1662197-3-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-11ipv6: sr: add missing seg6_local_exitHangbin Liu1-0/+1
Currently, we only call seg6_local_exit() in seg6_init() if seg6_local_init() failed. But forgot to call it in seg6_exit(). Fixes: d1df6fd8a1d2 ("ipv6: sr: define core operations for seg6local lightweight tunnel") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240509131812.1662197-2-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-10net: ipv6: fix wrong start position when receive hop-by-hop fragmentgaoxingwang1-1/+1
In IPv6, ipv6_rcv_core will parse the hop-by-hop type extension header and increase skb->transport_header by one extension header length. But if there are more other extension headers like fragment header at this time, the skb->transport_header points to the second extension header, not the transport layer header or the first extension header. This will result in the start and nexthdrp variable not pointing to the same position in ipv6frag_thdr_trunced, and ipv6_skip_exthdr returning incorrect offset and frag_off.Sometimes,the length of the last sharded packet is smaller than the calculated incorrect offset, resulting in packet loss. We can use network header to offset and calculate the correct position to solve this problem. Fixes: 9d9e937b1c8b (ipv6/netfilter: Discard first fragment not including all headers) Signed-off-by: Gao Xingwang <gaoxingwang1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-10tcp: get rid of twsk_unique()Eric Dumazet2-2/+3
DCCP is going away soon, and had no twsk_unique() method. We can directly call tcp_twsk_unique() for TCP sockets. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240507164140.940547-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-4/+12
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c 35d92abfbad8 ("net: hns3: fix kernel crash when devlink reload during initialization") 2a1a1a7b5fd7 ("net: hns3: add command queue trace for hns3") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-09ipv6: prevent NULL dereference in ip6_output()Eric Dumazet1-1/+1
According to syzbot, there is a chance that ip6_dst_idev() returns NULL in ip6_output(). Most places in IPv6 stack deal with a NULL idev just fine, but not here. syzbot reported: general protection fault, probably for non-canonical address 0xdffffc00000000bc: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x00000000000005e0-0x00000000000005e7] CPU: 0 PID: 9775 Comm: syz-executor.4 Not tainted 6.9.0-rc5-syzkaller-00157-g6a30653b604a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:ip6_output+0x231/0x3f0 net/ipv6/ip6_output.c:237 Code: 3c 1e 00 49 89 df 74 08 4c 89 ef e8 19 58 db f7 48 8b 44 24 20 49 89 45 00 49 89 c5 48 8d 9d e0 05 00 00 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 4c 8b 74 24 28 0f 85 61 01 00 00 8b 1b 31 ff RSP: 0018:ffffc9000927f0d8 EFLAGS: 00010202 RAX: 00000000000000bc RBX: 00000000000005e0 RCX: 0000000000040000 RDX: ffffc900131f9000 RSI: 0000000000004f47 RDI: 0000000000004f48 RBP: 0000000000000000 R08: ffffffff8a1f0b9a R09: 1ffffffff1f51fad R10: dffffc0000000000 R11: fffffbfff1f51fae R12: ffff8880293ec8c0 R13: ffff88805d7fc000 R14: 1ffff1100527d91a R15: dffffc0000000000 FS: 00007f135c6856c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000080 CR3: 0000000064096000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> NF_HOOK include/linux/netfilter.h:314 [inline] ip6_xmit+0xefe/0x17f0 net/ipv6/ip6_output.c:358 sctp_v6_xmit+0x9f2/0x13f0 net/sctp/ipv6.c:248 sctp_packet_transmit+0x26ad/0x2ca0 net/sctp/output.c:653 sctp_packet_singleton+0x22c/0x320 net/sctp/outqueue.c:783 sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline] sctp_outq_flush+0x6d5/0x3e20 net/sctp/outqueue.c:1212 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x59cc/0x60c0 net/sctp/sm_sideeffect.c:1169 sctp_primitive_ASSOCIATE+0x95/0xc0 net/sctp/primitive.c:73 __sctp_connect+0x9cd/0xe30 net/sctp/socket.c:1234 sctp_connect net/sctp/socket.c:4819 [inline] sctp_inet_connect+0x149/0x1f0 net/sctp/socket.c:4834 __sys_connect_file net/socket.c:2048 [inline] __sys_connect+0x2df/0x310 net/socket.c:2065 __do_sys_connect net/socket.c:2075 [inline] __se_sys_connect net/socket.c:2072 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2072 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 778d80be5269 ("ipv6: Add disable_ipv6 sysctl to disable IPv6 operaion on specific interface.") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com> Link: https://lore.kernel.org/r/20240507161842.773961-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-09ipv6: fib6_rules: avoid possible NULL dereference in fib6_rule_action()Eric Dumazet1-1/+5
syzbot is able to trigger the following crash [1], caused by unsafe ip6_dst_idev() use. Indeed ip6_dst_idev() can return NULL, and must always be checked. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 31648 Comm: syz-executor.0 Not tainted 6.9.0-rc4-next-20240417-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__fib6_rule_action net/ipv6/fib6_rules.c:237 [inline] RIP: 0010:fib6_rule_action+0x241/0x7b0 net/ipv6/fib6_rules.c:267 Code: 02 00 00 49 8d 9f d8 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 f9 32 bf f7 48 8b 1b 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 e0 32 bf f7 4c 8b 03 48 89 ef 4c RSP: 0018:ffffc9000fc1f2f0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1a772f98c8186700 RDX: 0000000000000003 RSI: ffffffff8bcac4e0 RDI: ffffffff8c1f9760 RBP: ffff8880673fb980 R08: ffffffff8fac15ef R09: 1ffffffff1f582bd R10: dffffc0000000000 R11: fffffbfff1f582be R12: dffffc0000000000 R13: 0000000000000080 R14: ffff888076509000 R15: ffff88807a029a00 FS: 00007f55e82ca6c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31d23000 CR3: 0000000022b66000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> fib_rules_lookup+0x62c/0xdb0 net/core/fib_rules.c:317 fib6_rule_lookup+0x1fd/0x790 net/ipv6/fib6_rules.c:108 ip6_route_output_flags_noref net/ipv6/route.c:2637 [inline] ip6_route_output_flags+0x38e/0x610 net/ipv6/route.c:2649 ip6_route_output include/net/ip6_route.h:93 [inline] ip6_dst_lookup_tail+0x189/0x11a0 net/ipv6/ip6_output.c:1120 ip6_dst_lookup_flow+0xb9/0x180 net/ipv6/ip6_output.c:1250 sctp_v6_get_dst+0x792/0x1e20 net/sctp/ipv6.c:326 sctp_transport_route+0x12c/0x2e0 net/sctp/transport.c:455 sctp_assoc_add_peer+0x614/0x15c0 net/sctp/associola.c:662 sctp_connect_new_asoc+0x31d/0x6c0 net/sctp/socket.c:1099 __sctp_connect+0x66d/0xe30 net/sctp/socket.c:1197 sctp_connect net/sctp/socket.c:4819 [inline] sctp_inet_connect+0x149/0x1f0 net/sctp/socket.c:4834 __sys_connect_file net/socket.c:2048 [inline] __sys_connect+0x2df/0x310 net/socket.c:2065 __do_sys_connect net/socket.c:2075 [inline] __se_sys_connect net/socket.c:2072 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2072 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 5e5f3f0f8013 ("[IPV6] ADDRCONF: Convert ipv6_get_saddr() to ipv6_dev_get_saddr().") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240507163145.835254-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-08ipv6: Fix potential uninit-value access in __ip6_make_skb()Shigeru Yoshida1-1/+1
As it was done in commit fc1092f51567 ("ipv4: Fix uninit-value access in __ip_make_skb()") for IPv4, check FLOWI_FLAG_KNOWN_NH on fl6->flowi6_flags instead of testing HDRINCL on the socket to avoid a race condition which causes uninit-value access. Fixes: ea30388baebc ("ipv6: Fix an uninit variable access bug in __ip6_make_skb()") Signed-off-by: Shigeru Yoshida <syoshida@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-08net: annotate writes on dev->mtu from ndo_change_mtu()Eric Dumazet2-2/+3
Simon reported that ndo_change_mtu() methods were never updated to use WRITE_ONCE(dev->mtu, new_mtu) as hinted in commit 501a90c94510 ("inet: protect against too small mtu values.") We read dev->mtu without holding RTNL in many places, with READ_ONCE() annotations. It is time to take care of ndo_change_mtu() methods to use corresponding WRITE_ONCE() Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Simon Horman <horms@kernel.org> Closes: https://lore.kernel.org/netdev/20240505144608.GB67882@kernel.org/ Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Simon Horman <horms@kernel.org> Acked-by: Shannon Nelson <shannon.nelson@amd.com> Link: https://lore.kernel.org/r/20240506102812.3025432-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-07rtnetlink: allow rtnl_fill_link_netnsid() to run under RCU protectionEric Dumazet1-1/+1
We want to be able to run rtnl_fill_ifinfo() under RCU protection instead of RTNL in the future. All rtnl_link_ops->get_link_net() methods already using dev_net() are ready. I added READ_ONCE() annotations on others. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-07Merge tag 'ipsec-next-2024-05-03' of ↵Jakub Kicinski2-25/+7
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2024-05-03 1) Remove Obsolete UDP_ENCAP_ESPINUDP_NON_IKE Support. This was defined by an early version of an IETF draft that did not make it to a standard. 2) Introduce direction attribute for xfrm states. xfrm states have a direction, a stsate can be used either for input or output packet processing. Add a direction to xfrm states to make it clear for what a xfrm state is used. * tag 'ipsec-next-2024-05-03' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next: xfrm: Restrict SA direction attribute to specific netlink message types xfrm: Add dir validation to "in" data path lookup xfrm: Add dir validation to "out" data path lookup xfrm: Add Direction to the SA in or out udpencap: Remove Obsolete UDP_ENCAP_ESPINUDP_NON_IKE Support ==================== Link: https://lore.kernel.org/r/20240503082732.2835810-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-06netfilter: use NF_DROP instead of -NF_DROPJason Xing1-1/+1
At the beginning in 2009 one patch [1] introduced collecting drop counter in nf_conntrack_in() by returning -NF_DROP. Later, another patch [2] changed the return value of tcp_packet() which now is renamed to nf_conntrack_tcp_packet() from -NF_DROP to NF_DROP. As we can see, that -NF_DROP should be corrected. Similarly, there are other two points where the -NF_DROP is used. Well, as NF_DROP is equal to 0, inverting NF_DROP makes no sense as patch [2] said many years ago. [1] commit 7d1e04598e5e ("netfilter: nf_conntrack: account packets drop by tcp_packet()") [2] commit ec8d540969da ("netfilter: conntrack: fix dropping packet after l4proto->packet()") Signed-off-by: Jason Xing <kernelxing@tencent.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-05-06net: add heuristic for enabling TCP fraglist GROFelix Fietkau1-0/+35
When forwarding TCP after GRO, software segmentation is very expensive, especially when the checksum needs to be recalculated. One case where that's currently unavoidable is when routing packets over PPPoE. Performance improves significantly when using fraglist GRO implemented in the same way as for UDP. When NETIF_F_GRO_FRAGLIST is enabled, perform a lookup for an established socket in the same netns as the receiving device. While this may not cover all relevant use cases in multi-netns configurations, it should be good enough for most configurations that need this. Here's a measurement of running 2 TCP streams through a MediaTek MT7622 device (2-core Cortex-A53), which runs NAT with flow offload enabled from one ethernet port to PPPoE on another ethernet port + cake qdisc set to 1Gbps. rx-gro-list off: 630 Mbit/s, CPU 35% idle rx-gro-list on: 770 Mbit/s, CPU 40% idle Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Felix Fietkau <nbd@nbd.name> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-06net: create tcp_gro_header_pull helper functionFelix Fietkau1-5/+13
Pull the code out of tcp_gro_receive in order to access the tcp header from tcp4/6_gro_receive. Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Felix Fietkau <nbd@nbd.name> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-06net: add code for TCP fraglist GROFelix Fietkau1-0/+9
This implements fraglist GRO similar to how it's handled in UDP, however no functional changes are added yet. The next change adds a heuristic for using fraglist GRO instead of regular GRO. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Felix Fietkau <nbd@nbd.name> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-06net: add support for segmenting TCP fraglist GSO packetsFelix Fietkau1-0/+58
Preparation for adding TCP fraglist GRO support. It expects packets to be combined in a similar way as UDP fraglist GSO packets. For IPv4 packets, NAT is handled in the same way as UDP fraglist GSO. Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Felix Fietkau <nbd@nbd.name> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-04Merge tag 'ipsec-2024-05-02' of ↵Jakub Kicinski1-1/+5
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2024-05-02 1) Fix an error pointer dereference in xfrm_in_fwd_icmp. From Antony Antony. 2) Preserve vlan tags for ESP transport mode software GRO. From Paul Davey. 3) Fix a spelling mistake in an uapi xfrm.h comment. From Anotny Antony. * tag 'ipsec-2024-05-02' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec: xfrm: Correct spelling mistake in xfrm.h comment xfrm: Preserve vlan tags for transport mode software GRO xfrm: fix possible derferencing in error path ==================== Link: https://lore.kernel.org/r/20240502084838.2269355-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-03netfilter: Remove the now superfluous sentinel elements from ctl_table arrayJoel Granados1-1/+0
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) * Remove sentinel elements from ctl_table structs * Remove instances where an array element is zeroed out to make it look like a sentinel. This is not longer needed and is safe after commit c899710fe7f9 ("networking: Update to register_net_sysctl_sz") added the array size to the ctl_table registration * Remove the need for having __NF_SYSCTL_CT_LAST_SYSCTL as the sysctl array size is now in NF_SYSCTL_CT_LAST_SYSCTL * Remove extra element in ctl_table arrays declarations Acked-by: Kees Cook <keescook@chromium.org> # loadpin & yama Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-03net: ipv{6,4}: Remove the now superfluous sentinel elements from ctl_table arrayJoel Granados6-19/+6
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) * Remove sentinel element from ctl_table structs. * Remove the zeroing out of an array element (to make it look like a sentinel) in sysctl_route_net_init And ipv6_route_sysctl_init. This is not longer needed and is safe after commit c899710fe7f9 ("networking: Update to register_net_sysctl_sz") added the array size to the ctl_table registration. * Remove extra sentinel element in the declaration of devinet_vars. * Removed the "-1" in __devinet_sysctl_register, sysctl_route_net_init, ipv6_sysctl_net_init and ipv4_sysctl_init_net that adjusted for having an extra empty element when looping over ctl_table arrays * Replace the for loop stop condition in __addrconf_sysctl_register that tests for procname == NULL with one that depends on array size * Removing the unprivileged user check in ipv6_route_sysctl_init is safe as it is replaced by calling ipv6_route_sysctl_table_size; introduced in commit c899710fe7f9 ("networking: Update to register_net_sysctl_sz") * Use a table_size variable to keep the value of ARRAY_SIZE Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-2/+5
Cross-merge networking fixes after downstream PR. Conflicts: include/linux/filter.h kernel/bpf/core.c 66e13b615a0c ("bpf: verifier: prevent userspace memory access") d503a04f8bc0 ("bpf: Add support for certain atomics in bpf_arena to x86 JIT") https://lore.kernel.org/all/20240429114939.210328b0@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-02net: gro: fix udp bad offset in socket lookup by adding ↵Richard Gobert3-2/+5
{inner_}network_offset to napi_gro_cb Commits a602456 ("udp: Add GRO functions to UDP socket") and 57c67ff ("udp: additional GRO support") introduce incorrect usage of {ip,ipv6}_hdr in the complete phase of gro. The functions always return skb->network_header, which in the case of encapsulated packets at the gro complete phase, is always set to the innermost L3 of the packet. That means that calling {ip,ipv6}_hdr for skbs which completed the GRO receive phase (both in gro_list and *_gro_complete) when parsing an encapsulated packet's _outer_ L3/L4 may return an unexpected value. This incorrect usage leads to a bug in GRO's UDP socket lookup. udp{4,6}_lib_lookup_skb functions use ip_hdr/ipv6_hdr respectively. These *_hdr functions return network_header which will point to the innermost L3, resulting in the wrong offset being used in __udp{4,6}_lib_lookup with encapsulated packets. This patch adds network_offset and inner_network_offset to napi_gro_cb, and makes sure both are set correctly. To fix the issue, network_offsets union is used inside napi_gro_cb, in which both the outer and the inner network offsets are saved. Reproduction example: Endpoint configuration example (fou + local address bind) # ip fou add port 6666 ipproto 4 # ip link add name tun1 type ipip remote 2.2.2.1 local 2.2.2.2 encap fou encap-dport 5555 encap-sport 6666 mode ipip # ip link set tun1 up # ip a add 1.1.1.2/24 dev tun1 Netperf TCP_STREAM result on net-next before patch is applied: net-next main, GRO enabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 131072 16384 16384 5.28 2.37 net-next main, GRO disabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 131072 16384 16384 5.01 2745.06 patch applied, GRO enabled: $ netperf -H 1.1.1.2 -t TCP_STREAM -l 5 Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 131072 16384 16384 5.01 2877.38 Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket") Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-01ipv6: anycast: use call_rcu_hurry() in aca_put()Eric Dumazet1-3/+2
This is a followup of commit b5327b9a300e ("ipv6: use call_rcu_hurry() in fib6_info_release()"). I had another pmtu.sh failure, and found another lazy call_rcu() causing this failure. aca_free_rcu() calls fib6_info_release() which releases devices references. We must not delay it too much or risk unregister_netdevice/ref_tracker traces because references to netdev are not released in time. This should speedup device/netns dismantles when CONFIG_RCU_LAZY=y Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-01xfrm: Add dir validation to "in" data path lookupAntony Antony1-0/+7
Introduces validation for the x->dir attribute within the XFRM input data lookup path. If the configured direction does not match the expected direction, input, increment the XfrmInStateDirError counter and drop the packet to ensure data integrity and correct flow handling. grep -vw 0 /proc/net/xfrm_stat XfrmInStateDirError 1 Signed-off-by: Antony Antony <antony.antony@secunet.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-04-29ipv6: introduce dst_rt6_info() helperEric Dumazet11-45/+40
Instead of (struct rt6_info *)dst casts, we can use : #define dst_rt6_info(_ptr) \ container_of_const(_ptr, struct rt6_info, dst) Some places needed missing const qualifiers : ip6_confirm_neigh(), ipv6_anycast_destination(), ipv6_unicast_destination(), has_gateway() v2: added missing parts (David Ahern) Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>