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2019-12-18net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookupSabrina Dubroca2-6/+7
[ Upstream commit 6c8991f41546c3c472503dff1ea9daaddf9331c2 ] ipv6_stub uses the ip6_dst_lookup function to allow other modules to perform IPv6 lookups. However, this function skips the XFRM layer entirely. All users of ipv6_stub->ip6_dst_lookup use ip_route_output_flow (via the ip_route_output_key and ip_route_output helpers) for their IPv4 lookups, which calls xfrm_lookup_route(). This patch fixes this inconsistent behavior by switching the stub to ip6_dst_lookup_flow, which also calls xfrm_lookup_route(). This requires some changes in all the callers, as these two functions take different arguments and have different return types. Fixes: 5f81bd2e5d80 ("ipv6: export a stub for IPv6 symbols used by vxlan") Reported-by: Xiumei Mu <xmu@redhat.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-18net: ipv6: add net argument to ip6_dst_lookup_flowSabrina Dubroca7-12/+12
[ Upstream commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e ] This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow, as some modules currently pass a net argument without a socket to ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument"). Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-29ipv6/route: return if there is no fib_nh_gw_familyHangbin Liu1-1/+1
[ Upstream commit 004b39427f945696db30abb2c4e1a3856ffff819 ] Previously we will return directly if (!rt || !rt->fib6_nh.fib_nh_gw_family) in function rt6_probe(), but after commit cc3a86c802f0 ("ipv6: Change rt6_probe to take a fib6_nh"), the logic changed to return if there is fib_nh_gw_family. Fixes: cc3a86c802f0 ("ipv6: Change rt6_probe to take a fib6_nh") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12ipv6: fixes rt6_probe() and fib6_nh->last_probe initEric Dumazet1-3/+10
[ Upstream commit 1bef4c223b8588cf50433bdc2c6953d82949b3b3 ] While looking at a syzbot KCSAN report [1], I found multiple issues in this code : 1) fib6_nh->last_probe has an initial value of 0. While probably okay on 64bit kernels, this causes an issue on 32bit kernels since the time_after(jiffies, 0 + interval) might be false ~24 days after boot (for HZ=1000) 2) The data-race found by KCSAN I could use READ_ONCE() and WRITE_ONCE(), but we also can take the opportunity of not piling-up too many rt6_probe_deferred() works by using instead cmpxchg() so that only one cpu wins the race. [1] BUG: KCSAN: data-race in find_match / find_match write to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 1: rt6_probe net/ipv6/route.c:663 [inline] find_match net/ipv6/route.c:757 [inline] find_match+0x5bd/0x790 net/ipv6/route.c:733 __find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831 find_rr_leaf net/ipv6/route.c:852 [inline] rt6_select net/ipv6/route.c:896 [inline] fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164 ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200 ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452 fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117 ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484 ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497 ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049 ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150 inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106 inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline] tcp_xmit_probe_skb+0x19b/0x1d0 net/ipv4/tcp_output.c:3735 read to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 0: rt6_probe net/ipv6/route.c:657 [inline] find_match net/ipv6/route.c:757 [inline] find_match+0x521/0x790 net/ipv6/route.c:733 __find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831 find_rr_leaf net/ipv6/route.c:852 [inline] rt6_select net/ipv6/route.c:896 [inline] fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164 ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200 ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452 fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117 ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484 ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497 ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049 ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150 inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106 inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 18894 Comm: udevd Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: cc3a86c802f0 ("ipv6: Change rt6_probe to take a fib6_nh") Fixes: f547fac624be ("ipv6: rate-limit probes for neighbourless routes") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-10net: ensure correct skb->tstamp in various fragmentersEric Dumazet2-0/+6
[ Upstream commit 9669fffc1415bb0c30e5d2ec98a8e1c3a418cb9c ] Thomas found that some forwarded packets would be stuck in FQ packet scheduler because their skb->tstamp contained timestamps far in the future. We thought we addressed this point in commit 8203e2d844d3 ("net: clear skb->tstamp in forwarding paths") but there is still an issue when/if a packet needs to be fragmented. In order to meet EDT requirements, we have to make sure all fragments get the original skb->tstamp. Note that this original skb->tstamp should be zero in forwarding path, but might have a non zero value in output path if user decided so. Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thomas Bartschies <Thomas.Bartschies@cvk.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-10net: annotate accesses to sk->sk_incoming_cpuEric Dumazet2-2/+2
[ Upstream commit 7170a977743b72cf3eb46ef6ef89885dc7ad3621 ] This socket field can be read and written by concurrent cpus. Use READ_ONCE() and WRITE_ONCE() annotations to document this, and avoid some compiler 'optimizations'. KCSAN reported : BUG: KCSAN: data-race in tcp_v4_rcv / tcp_v4_rcv write to 0xffff88812220763c of 4 bytes by interrupt on cpu 0: sk_incoming_cpu_update include/net/sock.h:953 [inline] tcp_v4_rcv+0x1b3c/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189 read to 0xffff88812220763c of 4 bytes by interrupt on cpu 1: sk_incoming_cpu_update include/net/sock.h:952 [inline] tcp_v4_rcv+0x181a/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-10erspan: fix the tun_info options_len check for erspanXin Long1-2/+2
[ Upstream commit 2eb8d6d2910cfe3dc67dc056f26f3dd9c63d47cd ] The check for !md doens't really work for ip_tunnel_info_opts(info) which only does info + 1. Also to avoid out-of-bounds access on info, it should ensure options_len is not less than erspan_metadata in both erspan_xmit() and ip6erspan_tunnel_xmit(). Fixes: 1a66a836da ("gre: add collect_md mode to ERSPAN tunnel") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-29net: ipv6: fix listify ip6_rcv_finish in case of forwardingXin Long1-1/+3
[ Upstream commit c7a42eb49212f93a800560662d17d5293960d3c3 ] We need a similar fix for ipv6 as Commit 0761680d5215 ("net: ipv4: fix listify ip_rcv_finish in case of forwarding") does for ipv4. This issue can be reprocuded by syzbot since Commit 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs") on net-next. The call trace was: kernel BUG at include/linux/skbuff.h:2225! RIP: 0010:__skb_pull include/linux/skbuff.h:2225 [inline] RIP: 0010:skb_pull+0xea/0x110 net/core/skbuff.c:1902 Call Trace: sctp_inq_pop+0x2f1/0xd80 net/sctp/inqueue.c:202 sctp_endpoint_bh_rcv+0x184/0x8d0 net/sctp/endpointola.c:385 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80 sctp_rcv+0x2807/0x3590 net/sctp/input.c:256 sctp6_rcv+0x17/0x30 net/sctp/ipv6.c:1049 ip6_protocol_deliver_rcu+0x2fe/0x1660 net/ipv6/ip6_input.c:397 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:438 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip6_input+0xe4/0x3f0 net/ipv6/ip6_input.c:447 dst_input include/net/dst.h:442 [inline] ip6_sublist_rcv_finish+0x98/0x1e0 net/ipv6/ip6_input.c:84 ip6_list_rcv_finish net/ipv6/ip6_input.c:118 [inline] ip6_sublist_rcv+0x80c/0xcf0 net/ipv6/ip6_input.c:282 ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:316 __netif_receive_skb_list_ptype net/core/dev.c:5049 [inline] __netif_receive_skb_list_core+0x5fc/0x9d0 net/core/dev.c:5097 __netif_receive_skb_list net/core/dev.c:5149 [inline] netif_receive_skb_list_internal+0x7eb/0xe60 net/core/dev.c:5244 gro_normal_list.part.0+0x1e/0xb0 net/core/dev.c:5757 gro_normal_list net/core/dev.c:5755 [inline] gro_normal_one net/core/dev.c:5769 [inline] napi_frags_finish net/core/dev.c:5782 [inline] napi_gro_frags+0xa6a/0xea0 net/core/dev.c:5855 tun_get_user+0x2e98/0x3fa0 drivers/net/tun.c:1974 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2020 Fixes: d8269e2cbf90 ("net: ipv6: listify ipv6_rcv() and ip6_rcv_finish()") Fixes: 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs") Reported-by: syzbot+eb349eeee854e389c36d@syzkaller.appspotmail.com Reported-by: syzbot+4a0643a653ac375612d1@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07udp: only do GSO if # of segs > 1Josh Hunt1-4/+7
[ Upstream commit 4094871db1d65810acab3d57f6089aa39ef7f648 ] Prior to this change an application sending <= 1MSS worth of data and enabling UDP GSO would fail if the system had SW GSO enabled, but the same send would succeed if HW GSO offload is enabled. In addition to this inconsistency the error in the SW GSO case does not get back to the application if sending out of a real device so the user is unaware of this failure. With this change we only perform GSO if the # of segments is > 1 even if the application has enabled segmentation. I've also updated the relevant udpgso selftests. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Josh Hunt <johunt@akamai.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07udp: fix gso_segs calculationsJosh Hunt1-0/+2
[ Upstream commit 44b321e5020d782ad6e8ae8183f09b163be6e6e2 ] Commit dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload") added gso_segs calculation, but incorrectly got sizeof() the pointer and not the underlying data type. In addition let's fix the v6 case. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Fixes: dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload") Signed-off-by: Josh Hunt <johunt@akamai.com> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07ipv6: Handle missing host route in __ipv6_ifa_notifyDavid Ahern1-5/+12
[ Upstream commit 2d819d250a1393a3e725715425ab70a0e0772a71 ] Rajendra reported a kernel panic when a link was taken down: [ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8 [ 6870.271856] IP: [<ffffffff8efc5764>] __ipv6_ifa_notify+0x154/0x290 <snip> [ 6870.570501] Call Trace: [ 6870.573238] [<ffffffff8efc58c6>] ? ipv6_ifa_notify+0x26/0x40 [ 6870.579665] [<ffffffff8efc98ec>] ? addrconf_dad_completed+0x4c/0x2c0 [ 6870.586869] [<ffffffff8efe70c6>] ? ipv6_dev_mc_inc+0x196/0x260 [ 6870.593491] [<ffffffff8efc9c6a>] ? addrconf_dad_work+0x10a/0x430 [ 6870.600305] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70 [ 6870.606732] [<ffffffff8ea93a7a>] ? process_one_work+0x18a/0x430 [ 6870.613449] [<ffffffff8ea93d6d>] ? worker_thread+0x4d/0x490 [ 6870.619778] [<ffffffff8ea93d20>] ? process_one_work+0x430/0x430 [ 6870.626495] [<ffffffff8ea99dd9>] ? kthread+0xd9/0xf0 [ 6870.632145] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70 [ 6870.638573] [<ffffffff8ea99d00>] ? kthread_park+0x60/0x60 [ 6870.644707] [<ffffffff8f01ae77>] ? ret_from_fork+0x57/0x70 [ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0 addrconf_dad_work is kicked to be scheduled when a device is brought up. There is a race between addrcond_dad_work getting scheduled and taking the rtnl lock and a process taking the link down (under rtnl). The latter removes the host route from the inet6_addr as part of addrconf_ifdown which is run for NETDEV_DOWN. The former attempts to use the host route in __ipv6_ifa_notify. If the down event removes the host route due to the race to the rtnl, then the BUG listed above occurs. Since the DAD sequence can not be aborted, add a check for the missing host route in __ipv6_ifa_notify. The only way this should happen is due to the previously mentioned race. The host route is created when the address is added to an interface; it is only removed on a down event where the address is kept. Add a warning if the host route is missing AND the device is up; this is a situation that should never happen. Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") Reported-by: Rajendra Dendukuri <rajendra.dendukuri@broadcom.com> Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07ipv6: drop incoming packets having a v4mapped source addressEric Dumazet1-0/+10
[ Upstream commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3 ] This began with a syzbot report. syzkaller was injecting IPv6 TCP SYN packets having a v4mapped source address. After an unsuccessful 4-tuple lookup, TCP creates a request socket (SYN_RECV) and calls reqsk_queue_hash_req() reqsk_queue_hash_req() calls sk_ehashfn(sk) At this point we have AF_INET6 sockets, and the heuristic used by sk_ehashfn() to either hash the IPv4 or IPv6 addresses is to use ipv6_addr_v4mapped(&sk->sk_v6_daddr) For the particular spoofed packet, we end up hashing V4 addresses which were not initialized by the TCP IPv6 stack, so KMSAN fired a warning. I first fixed sk_ehashfn() to test both source and destination addresses, but then faced various problems, including user-space programs like packetdrill that had similar assumptions. Instead of trying to fix the whole ecosystem, it is better to admit that we have a dual stack behavior, and that we can not build linux kernels without V4 stack anyway. The dual stack API automatically forces the traffic to be IPv4 if v4mapped addresses are used at bind() or connect(), so it makes no sense to allow IPv6 traffic to use the same v4mapped class. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05ipv6: fix a typo in fib6_rule_lookup()Eric Dumazet1-1/+1
[ Upstream commit 7b09c2d052db4b4ad0b27b97918b46a7746966fa ] Yi Ren reported an issue discovered by syzkaller, and bisected to the cited commit. Many thanks to Yi, this trivial patch does not reflect the patient work that has been done. Fixes: d64a1f574a29 ("ipv6: honor RT6_LOOKUP_F_DST_NOREF in rule lookup logic") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Wei Wang <weiwan@google.com> Bisected-and-reported-by: Yi Ren <c4tren@gmail.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05ipv6: do not free rt if FIB_LOOKUP_NOREF is set on suppress ruleJason A. Donenfeld1-1/+2
[ Upstream commit ca7a03c4175366a92cee0ccc4fec0038c3266e26 ] Commit 7d9e5f422150 removed references from certain dsts, but accounting for this never translated down into the fib6 suppression code. This bug was triggered by WireGuard users who use wg-quick(8), which uses the "suppress-prefix" directive to ip-rule(8) for routing all of their internet traffic without routing loops. The test case added here causes the reference underflow by causing packets to evaluate a suppress rule. Fixes: 7d9e5f422150 ("ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-21udp: correct reuseport selection with connected socketsWillem de Bruijn2-2/+5
[ Upstream commit acdcecc61285faed359f1a3568c32089cc3a8329 ] UDP reuseport groups can hold a mix unconnected and connected sockets. Ensure that connections only receive all traffic to their 4-tuple. Fast reuseport returns on the first reuseport match on the assumption that all matches are equal. Only if connections are present, return to the previous behavior of scoring all sockets. Record if connections are present and if so (1) treat such connected sockets as an independent match from the group, (2) only return 2-tuple matches from reuseport and (3) do not return on the first 2-tuple reuseport match to allow for a higher scoring match later. New field has_conns is set without locks. No other fields in the bitmap are modified at runtime and the field is only ever set unconditionally, so an RMW cannot miss a change. Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection") Link: http://lkml.kernel.org/r/CA+FuTSfRP09aJNYRt04SS6qj22ViiOEWaWmLAwX0psk8-PGNxw@mail.gmail.com Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Craig Gallek <kraig@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-21ip6_gre: fix a dst leak in ip6erspan_tunnel_xmitXin Long1-1/+1
[ Upstream commit 28e486037747c2180470b77c290d4090ad42f259 ] In ip6erspan_tunnel_xmit(), if the skb will not be sent out, it has to be freed on the tx_err path. Otherwise when deleting a netns, it would cause dst/dev to leak, and dmesg shows: unregister_netdevice: waiting for lo to become free. Usage count = 1 Fixes: ef7baf5e083c ("ip6_gre: add ip6 erspan collect_md mode") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-12ipv6: Fix the link time qualifier of 'ping_v6_proc_exit_net()'Christophe JAILLET1-1/+1
The '.exit' functions from 'pernet_operations' structure should be marked as __net_exit, not __net_init. Fixes: d862e5461423 ("net: ipv6: Implement /proc/net/icmp6.") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-07ipv6: addrconf_f6i_alloc - fix non-null pointer check to !IS_ERR()Maciej Żenczykowski1-1/+1
Fixes a stupid bug I recently introduced... ip6_route_info_create() returns an ERR_PTR(err) and not a NULL on error. Fixes: d55a2e374a94 ("net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)'") Cc: David Ahern <dsahern@gmail.com> Cc: Lorenzo Colitti <lorenzo@google.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Maciej Żenczykowski <maze@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-05net: Properly update v4 routes with v6 nexthopDonald Sharp1-5/+6
When creating a v4 route that uses a v6 nexthop from a nexthop group. Allow the kernel to properly send the nexthop as v6 via the RTA_VIA attribute. Broken behavior: $ ip nexthop add via fe80::9 dev eth0 $ ip nexthop show id 1 via fe80::9 dev eth0 scope link $ ip route add 4.5.6.7/32 nhid 1 $ ip route show default via 10.0.2.2 dev eth0 4.5.6.7 nhid 1 via 254.128.0.0 dev eth0 10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15 $ Fixed behavior: $ ip nexthop add via fe80::9 dev eth0 $ ip nexthop show id 1 via fe80::9 dev eth0 scope link $ ip route add 4.5.6.7/32 nhid 1 $ ip route show default via 10.0.2.2 dev eth0 4.5.6.7 nhid 1 via inet6 fe80::9 dev eth0 10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15 $ v2, v3: Addresses code review comments from David Ahern Fixes: dcb1ecb50edf (“ipv4: Prepare for fib6_nh from a nexthop object”) Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-05ipv6: Fix RTA_MULTIPATH with nexthop objectsDavid Ahern1-1/+1
A change to the core nla helpers was missed during the push of the nexthop changes. rt6_fill_node_nexthop should be calling nla_nest_start_noflag not nla_nest_start. Currently, iproute2 does not print multipath data because of parsing issues with the attribute. Fixes: f88d8ea67fbd ("ipv6: Plumb support for nexthop object in a fib6_info") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-05net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)Maciej Żenczykowski1-2/+6
There is a subtle change in behaviour introduced by: commit c7a1ce397adacaf5d4bb2eab0a738b5f80dc3e43 'ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create' Before that patch /proc/net/ipv6_route includes: 00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo Afterwards /proc/net/ipv6_route includes: 00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80240001 lo ie. the above commit causes the ::1/128 local (automatic) route to be flagged with RTF_ADDRCONF (0x040000). AFAICT, this is incorrect since these routes are *not* coming from RA's. As such, this patch restores the old behaviour. Fixes: c7a1ce397ada ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create") Cc: David Ahern <dsahern@gmail.com> Cc: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-29mld: fix memory leak in mld_del_delrec()Eric Dumazet1-2/+3
Similar to the fix done for IPv4 in commit e5b1c6c6277d ("igmp: fix memory leak in igmpv3_del_delrec()"), we need to make sure mca_tomb and mca_sources are not blindly overwritten. Using swap() then a call to ip6_mc_clear_src() will take care of the missing free. BUG: memory leak unreferenced object 0xffff888117d9db00 (size 64): comm "syz-executor247", pid 6918, jiffies 4294943989 (age 25.350s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 fe 88 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000005b463030>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<000000005b463030>] slab_post_alloc_hook mm/slab.h:522 [inline] [<000000005b463030>] slab_alloc mm/slab.c:3319 [inline] [<000000005b463030>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548 [<00000000939cbf94>] kmalloc include/linux/slab.h:552 [inline] [<00000000939cbf94>] kzalloc include/linux/slab.h:748 [inline] [<00000000939cbf94>] ip6_mc_add1_src net/ipv6/mcast.c:2236 [inline] [<00000000939cbf94>] ip6_mc_add_src+0x31f/0x420 net/ipv6/mcast.c:2356 [<00000000d8972221>] ip6_mc_source+0x4a8/0x600 net/ipv6/mcast.c:449 [<000000002b203d0d>] do_ipv6_setsockopt.isra.0+0x1b92/0x1dd0 net/ipv6/ipv6_sockglue.c:748 [<000000001f1e2d54>] ipv6_setsockopt+0x89/0xd0 net/ipv6/ipv6_sockglue.c:944 [<00000000c8f7bdf9>] udpv6_setsockopt+0x4e/0x90 net/ipv6/udp.c:1558 [<000000005a9a0c5e>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3139 [<00000000910b37b2>] __sys_setsockopt+0x10f/0x220 net/socket.c:2084 [<00000000e9108023>] __do_sys_setsockopt net/socket.c:2100 [inline] [<00000000e9108023>] __se_sys_setsockopt net/socket.c:2097 [inline] [<00000000e9108023>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2097 [<00000000f4818160>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296 [<000000008d367e8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when set link down") Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-24ipv6: propagate ipv6_add_dev's error returns out of ipv6_find_idevSabrina Dubroca1-8/+8
Currently, ipv6_find_idev returns NULL when ipv6_add_dev fails, ignoring the specific error value. This results in addrconf_add_dev returning ENOBUFS in all cases, which is unfortunate in cases such as: # ip link add dummyX type dummy # ip link set dummyX mtu 1200 up # ip addr add 2000::/64 dev dummyX RTNETLINK answers: No buffer space available Commit a317a2f19da7 ("ipv6: fail early when creating netdev named all or default") introduced error returns in ipv6_add_dev. Before that, that function would simply return NULL for all failures. Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-22ipv6/addrconf: allow adding multicast addr if IFA_F_MCAUTOJOIN is setHangbin Liu1-1/+2
In commit 93a714d6b53d ("multicast: Extend ip address command to enable multicast group join/leave on") we added a new flag IFA_F_MCAUTOJOIN to make user able to add multicast address on ethernet interface. This works for IPv4, but not for IPv6. See the inet6_addr_add code. static int inet6_addr_add() { ... if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) { ipv6_mc_config(net->ipv6.mc_autojoin_sk, true...) } ifp = ipv6_add_addr(idev, cfg, true, extack); <- always fail with maddr if (!IS_ERR(ifp)) { ... } else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) { ipv6_mc_config(net->ipv6.mc_autojoin_sk, false...) } } But in ipv6_add_addr() it will check the address type and reject multicast address directly. So this feature is never worked for IPv6. We should not remove the multicast address check totally in ipv6_add_addr(), but could accept multicast address only when IFA_F_MCAUTOJOIN flag supplied. v2: update commit description Fixes: 93a714d6b53d ("multicast: Extend ip address command to enable multicast group join/leave on") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-09inet: frags: re-introduce skb coalescing for local deliveryGuillaume Nault2-2/+2
Before commit d4289fcc9b16 ("net: IP6 defrag: use rbtrees for IPv6 defrag"), a netperf UDP_STREAM test[0] using big IPv6 datagrams (thus generating many fragments) and running over an IPsec tunnel, reported more than 6Gbps throughput. After that patch, the same test gets only 9Mbps when receiving on a be2net nic (driver can make a big difference here, for example, ixgbe doesn't seem to be affected). By reusing the IPv4 defragmentation code, IPv6 lost fragment coalescing (IPv4 fragment coalescing was dropped by commit 14fe22e33462 ("Revert "ipv4: use skb coalescing in defragmentation"")). Without fragment coalescing, be2net runs out of Rx ring entries and starts to drop frames (ethtool reports rx_drops_no_frags errors). Since the netperf traffic is only composed of UDP fragments, any lost packet prevents reassembly of the full datagram. Therefore, fragments which have no possibility to ever get reassembled pile up in the reassembly queue, until the memory accounting exeeds the threshold. At that point no fragment is accepted anymore, which effectively discards all netperf traffic. When reassembly timeout expires, some stale fragments are removed from the reassembly queue, so a few packets can be received, reassembled and delivered to the netperf receiver. But the nic still drops frames and soon the reassembly queue gets filled again with stale fragments. These long time frames where no datagram can be received explain why the performance drop is so significant. Re-introducing fragment coalescing is enough to get the initial performances again (6.6Gbps with be2net): driver doesn't drop frames anymore (no more rx_drops_no_frags errors) and the reassembly engine works at full speed. This patch is quite conservative and only coalesces skbs for local IPv4 and IPv6 delivery (in order to avoid changing skb geometry when forwarding). Coalescing could be extended in the future if need be, as more scenarios would probably benefit from it. [0]: Test configuration Sender: ip xfrm policy flush ip xfrm state flush ip xfrm state add src fc00:1::1 dst fc00:2::1 proto esp spi 0x1000 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:1::1 dst fc00:2::1 ip xfrm policy add src fc00:1::1 dst fc00:2::1 dir in tmpl src fc00:1::1 dst fc00:2::1 proto esp mode transport action allow ip xfrm state add src fc00:2::1 dst fc00:1::1 proto esp spi 0x1001 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:2::1 dst fc00:1::1 ip xfrm policy add src fc00:2::1 dst fc00:1::1 dir out tmpl src fc00:2::1 dst fc00:1::1 proto esp mode transport action allow netserver -D -L fc00:2::1 Receiver: ip xfrm policy flush ip xfrm state flush ip xfrm state add src fc00:2::1 dst fc00:1::1 proto esp spi 0x1001 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:2::1 dst fc00:1::1 ip xfrm policy add src fc00:2::1 dst fc00:1::1 dir in tmpl src fc00:2::1 dst fc00:1::1 proto esp mode transport action allow ip xfrm state add src fc00:1::1 dst fc00:2::1 proto esp spi 0x1000 aead 'rfc4106(gcm(aes))' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b 96 mode transport sel src fc00:1::1 dst fc00:2::1 ip xfrm policy add src fc00:1::1 dst fc00:2::1 dir out tmpl src fc00:1::1 dst fc00:2::1 proto esp mode transport action allow netperf -H fc00:2::1 -f k -P 0 -L fc00:1::1 -l 60 -t UDP_STREAM -I 99,5 -i 5,5 -T5,5 -6 Signed-off-by: Guillaume Nault <gnault@redhat.com> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-05ipv6: Fix unbalanced rcu locking in rt6_update_exception_stamp_rtDavid Ahern1-1/+1
The nexthop path in rt6_update_exception_stamp_rt needs to call rcu_read_unlock if it fails to find a fib6_nh match rather than just returning. Fixes: e659ba31d806 ("ipv6: Handle all fib6_nh in a nexthop in exception handling") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-27ip6_tunnel: fix possible use-after-free on xmitHaishuang Yan1-4/+2
ip4ip6/ip6ip6 tunnels run iptunnel_handle_offloads on xmit which can cause a possible use-after-free accessing iph/ipv6h pointer since the packet will be 'uncloned' running pskb_expand_head if it is a cloned gso skb. Fixes: 0e9a709560db ("ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packets") Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-24ip6_gre: reload ipv6h in prepare_ip6gre_xmit_ipv6Haishuang Yan1-1/+2
Since ip6_tnl_parse_tlv_enc_lim() can call pskb_may_pull() which may change skb->data, so we need to re-load ipv6h at the right place. Fixes: 898b29798e36 ("ip6_gre: Refactor ip6gre xmit codes") Cc: William Tu <u9012063@gmail.com> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Acked-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller2-2/+8
Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: 1) Fix a deadlock when module is requested via netlink_bind() in nfnetlink, from Florian Westphal. 2) Fix ipt_rpfilter and ip6t_rpfilter with VRF, from Miaohe Lin. 3) Skip master comparison in SIP helper to fix expectation clash under two valid scenarios, from xiao ruizhu. 4) Remove obsolete comments in nf_conntrack codebase, from Yonatan Goldschmidt. 5) Fix redirect extension module autoload, from Christian Hesse. 6) Fix incorrect mssg option sent to client in synproxy, from Fernando Fernandez. 7) Fix incorrect window calculations in TCP conntrack, from Florian Westphal. 8) Don't bail out when updating basechain policy due to recent offload works, also from Florian. 9) Allow symhash to use modulus 1 as other hash extensions do, from Laura.Garcia. 10) Missing NAT chain module autoload for the inet family, from Phil Sutter. 11) Fix missing adjustment of TCP RST packet in synproxy, from Fernando Fernandez. 12) Skip EAGAIN path when nft_meta_bridge is built-in or not selected. 13) Conntrack bridge does not depend on nf_tables_bridge. 14) Turn NF_TABLES_BRIDGE into tristate to fix possible link break of nft_meta_bridge, from Arnd Bergmann. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds3-6/+27
Pull networking fixes from David Miller: 1) Fix AF_XDP cq entry leak, from Ilya Maximets. 2) Fix handling of PHY power-down on RTL8411B, from Heiner Kallweit. 3) Add some new PCI IDs to iwlwifi, from Ihab Zhaika. 4) Fix handling of neigh timers wrt. entries added by userspace, from Lorenzo Bianconi. 5) Various cases of missing of_node_put(), from Nishka Dasgupta. 6) The new NET_ACT_CT needs to depend upon NF_NAT, from Yue Haibing. 7) Various RDS layer fixes, from Gerd Rausch. 8) Fix some more fallout from TCQ_F_CAN_BYPASS generalization, from Cong Wang. 9) Fix FIB source validation checks over loopback, also from Cong Wang. 10) Use promisc for unsupported number of filters, from Justin Chen. 11) Missing sibling route unlink on failure in ipv6, from Ido Schimmel. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (90 commits) tcp: fix tcp_set_congestion_control() use from bpf hook ag71xx: fix return value check in ag71xx_probe() ag71xx: fix error return code in ag71xx_probe() usb: qmi_wwan: add D-Link DWM-222 A2 device ID bnxt_en: Fix VNIC accounting when enabling aRFS on 57500 chips. net: dsa: sja1105: Fix missing unlock on error in sk_buff() gve: replace kfree with kvfree selftests/bpf: fix test_xdp_noinline on s390 selftests/bpf: fix "valid read map access into a read-only array 1" on s390 net/mlx5: Replace kfree with kvfree MAINTAINERS: update netsec driver ipv6: Unlink sibling route in case of failure liquidio: Replace vmalloc + memset with vzalloc udp: Fix typo in net/ipv4/udp.c net: bcmgenet: use promisc for unsupported filters ipv6: rt6_check should return NULL if 'from' is NULL tipc: initialize 'validated' field of received packets selftests: add a test case for rp_filter fib: relax source validation check for loopback packets mlxsw: spectrum: Do not process learned records with a dummy FID ...
2019-07-19proc/sysctl: add shared variables for range checkMatteo Croce3-15/+8
In the sysctl code the proc_dointvec_minmax() function is often used to validate the user supplied value between an allowed range. This function uses the extra1 and extra2 members from struct ctl_table as minimum and maximum allowed value. On sysctl handler declaration, in every source file there are some readonly variables containing just an integer which address is assigned to the extra1 and extra2 members, so the sysctl range is enforced. The special values 0, 1 and INT_MAX are very often used as range boundary, leading duplication of variables like zero=0, one=1, int_max=INT_MAX in different source files: $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l 248 Add a const int array containing the most commonly used values, some macros to refer more easily to the correct array member, and use them instead of creating a local one for every object file. This is the bloat-o-meter output comparing the old and new binary compiled with the default Fedora config: # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164) Data old new delta sysctl_vals - 12 +12 __kstrtab_sysctl_vals - 12 +12 max 14 10 -4 int_max 16 - -16 one 68 - -68 zero 128 28 -100 Total: Before=20583249, After=20583085, chg -0.00% [mcroce@redhat.com: tipc: remove two unused variables] Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com [akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c] [arnd@arndb.de: proc/sysctl: make firmware loader table conditional] Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de [akpm@linux-foundation.org: fix fs/eventpoll.c] Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18ipv6: Unlink sibling route in case of failureIdo Schimmel1-1/+17
When a route needs to be appended to an existing multipath route, fib6_add_rt2node() first appends it to the siblings list and increments the number of sibling routes on each sibling. Later, the function notifies the route via call_fib6_entry_notifiers(). In case the notification is vetoed, the route is not unlinked from the siblings list, which can result in a use-after-free. Fix this by unlinking the route from the siblings list before returning an error. Audited the rest of the call sites from which the FIB notification chain is called and could not find more problems. Fixes: 2233000cba40 ("net/ipv6: Move call_fib6_entry_notifiers up for route adds") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reported-by: Alexander Petrovskiy <alexpe@mellanox.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-18ipv6: rt6_check should return NULL if 'from' is NULLDavid Ahern1-1/+1
Paul reported that l2tp sessions were broken after the commit referenced in the Fixes tag. Prior to this commit rt6_check returned NULL if the rt6_info 'from' was NULL - ie., the dst_entry was disconnected from a FIB entry. Restore that behavior. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Reported-by: Paul Donohue <linux-kernel@PaulSD.com> Tested-by: Paul Donohue <linux-kernel@PaulSD.com> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-16netfilter: synproxy: fix erroneous tcp mss optionFernando Fernandez Mancera1-0/+2
Now synproxy sends the mss value set by the user on client syn-ack packet instead of the mss value that client announced. Fixes: 48b1de4c110a ("netfilter: add SYNPROXY core/target") Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-07-16netfilter: Fix rpfilter dropping vrf packets by mistakeMiaohe Lin1-2/+6
When firewalld is enabled with ipv4/ipv6 rpfilter, vrf ipv4/ipv6 packets will be dropped. Vrf device will pass through netfilter hook twice. One with enslaved device and another one with l3 master device. So in device may dismatch witch out device because out device is always enslaved device.So failed with the check of the rpfilter and drop the packets by mistake. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-07-14sit: use dst_cache in ipip6_tunnel_xmitHaishuang Yan1-4/+9
Same as other ip tunnel, use dst_cache in xmit action to avoid unnecessary fib lookups. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-12ipv6: fix static key imbalance in fl_create()Eric Dumazet1-3/+6
fl_create() should call static_branch_deferred_inc() only in case of success. Also we should not call fl_free() in error path, as this could cause a static key imbalance. jump label: negative count! WARNING: CPU: 0 PID: 15907 at kernel/jump_label.c:221 static_key_slow_try_dec kernel/jump_label.c:221 [inline] WARNING: CPU: 0 PID: 15907 at kernel/jump_label.c:221 static_key_slow_try_dec+0x1ab/0x1d0 kernel/jump_label.c:206 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 15907 Comm: syz-executor.2 Not tainted 5.2.0-rc6+ #62 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 panic+0x2cb/0x744 kernel/panic.c:219 __warn.cold+0x20/0x4d kernel/panic.c:576 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:986 RIP: 0010:static_key_slow_try_dec kernel/jump_label.c:221 [inline] RIP: 0010:static_key_slow_try_dec+0x1ab/0x1d0 kernel/jump_label.c:206 Code: c0 e8 e9 3e e5 ff 83 fb 01 0f 85 32 ff ff ff e8 5b 3d e5 ff 45 31 ff eb a0 e8 51 3d e5 ff 48 c7 c7 40 99 92 87 e8 13 75 b7 ff <0f> 0b eb 8b 4c 89 e7 e8 a9 c0 1e 00 e9 de fe ff ff e8 bf 6d b7 ff RSP: 0018:ffff88805f9c7450 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000000000000 RDX: 000000000000e3e1 RSI: ffffffff815adb06 RDI: ffffed100bf38e7c RBP: ffff88805f9c74e0 R08: ffff88806acf0700 R09: ffffed1015d060a9 R10: ffffed1015d060a8 R11: ffff8880ae830547 R12: ffffffff89832ce0 R13: ffff88805f9c74b8 R14: 1ffff1100bf38e8b R15: 00000000ffffff01 __static_key_slow_dec_deferred+0x65/0x110 kernel/jump_label.c:272 fl_free+0xa9/0xe0 net/ipv6/ip6_flowlabel.c:121 fl_create+0x6af/0x9f0 net/ipv6/ip6_flowlabel.c:457 ipv6_flowlabel_opt+0x80e/0x2730 net/ipv6/ip6_flowlabel.c:624 do_ipv6_setsockopt.isra.0+0x2119/0x4100 net/ipv6/ipv6_sockglue.c:825 ipv6_setsockopt+0xf6/0x170 net/ipv6/ipv6_sockglue.c:944 tcp_setsockopt net/ipv4/tcp.c:3131 [inline] tcp_setsockopt+0x8f/0xe0 net/ipv4/tcp.c:3125 sock_common_setsockopt+0x94/0xd0 net/core/sock.c:3130 __sys_setsockopt+0x253/0x4b0 net/socket.c:2080 __do_sys_setsockopt net/socket.c:2096 [inline] __se_sys_setsockopt net/socket.c:2093 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2093 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4597c9 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2670556c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004597c9 RDX: 0000000000000020 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 000000000075bfc8 R08: 000000000000fdf7 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00007f26705576d4 R13: 00000000004cec00 R14: 00000000004dd520 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-12ipv6: fix potential crash in ip6_datagram_dst_update()Eric Dumazet1-1/+1
Willem forgot to change one of the calls to fl6_sock_lookup(), which can now return an error or NULL. syzbot reported : kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 31763 Comm: syz-executor.0 Not tainted 5.2.0-rc6+ #63 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ip6_datagram_dst_update+0x559/0xc30 net/ipv6/datagram.c:83 Code: 00 00 e8 ea 29 3f fb 4d 85 f6 0f 84 96 04 00 00 e8 dc 29 3f fb 49 8d 7e 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 16 06 00 00 4d 8b 6e 20 e8 b4 29 3f fb 4c 89 ee RSP: 0018:ffff88809ba97ae0 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: ffff8880a81254b0 RCX: ffffc90008118000 RDX: 0000000000000003 RSI: ffffffff86319a84 RDI: 000000000000001e RBP: ffff88809ba97c10 R08: ffff888065e9e700 R09: ffffed1015d26c80 R10: ffffed1015d26c7f R11: ffff8880ae9363fb R12: ffff8880a8124f40 R13: 0000000000000001 R14: fffffffffffffffe R15: ffff88809ba97b40 FS: 00007f38e606a700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000202c0140 CR3: 00000000a026a000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __ip6_datagram_connect+0x5e9/0x1390 net/ipv6/datagram.c:246 ip6_datagram_connect+0x30/0x50 net/ipv6/datagram.c:269 ip6_datagram_connect_v6_only+0x69/0x90 net/ipv6/datagram.c:281 inet_dgram_connect+0x14a/0x2d0 net/ipv4/af_inet.c:571 __sys_connect+0x264/0x330 net/socket.c:1824 __do_sys_connect net/socket.c:1835 [inline] __se_sys_connect net/socket.c:1832 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1832 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4597c9 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f38e6069c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004597c9 RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f38e606a6d4 R13: 00000000004bfd07 R14: 00000000004d1838 R15: 00000000ffffffff Modules linked in: RIP: 0010:ip6_datagram_dst_update+0x559/0xc30 net/ipv6/datagram.c:83 Code: 00 00 e8 ea 29 3f fb 4d 85 f6 0f 84 96 04 00 00 e8 dc 29 3f fb 49 8d 7e 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 16 06 00 00 4d 8b 6e 20 e8 b4 29 3f fb 4c 89 ee Fixes: 59c820b2317f ("ipv6: elide flowlabel check if no exclusive leases exist") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-12ipv6: tcp: fix flowlabels reflection for RST packetsEric Dumazet1-1/+6
In 323a53c41292 ("ipv6: tcp: enable flowlabel reflection in some RST packets") and 50a8accf1062 ("ipv6: tcp: send consistent flowlabel in TIME_WAIT state") we took care of IPv6 flowlabel reflections for two cases. This patch takes care of the remaining case, when the RST packet is sent on behalf of a 'full' socket. In Marek use case, this was a socket in TCP_CLOSE state. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Marek Majkowski <marek@cloudflare.com> Tested-by: Marek Majkowski <marek@cloudflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-12ipv6: Use ipv6_authlen for lenyangxingwu7-8/+8
The length of AH header is computed manually as (hp->hdrlen+2)<<2. However, in include/linux/ipv6.h, a macro named ipv6_authlen is already defined for exactly the same job. This commit replaces the manual computation code with the macro. Signed-off-by: yangxingwu <xingwu.yang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds27-1235/+1830
Pull networking updates from David Miller: "Some highlights from this development cycle: 1) Big refactoring of ipv6 route and neigh handling to support nexthop objects configurable as units from userspace. From David Ahern. 2) Convert explored_states in BPF verifier into a hash table, significantly decreased state held for programs with bpf2bpf calls, from Alexei Starovoitov. 3) Implement bpf_send_signal() helper, from Yonghong Song. 4) Various classifier enhancements to mvpp2 driver, from Maxime Chevallier. 5) Add aRFS support to hns3 driver, from Jian Shen. 6) Fix use after free in inet frags by allocating fqdirs dynamically and reworking how rhashtable dismantle occurs, from Eric Dumazet. 7) Add act_ctinfo packet classifier action, from Kevin Darbyshire-Bryant. 8) Add TFO key backup infrastructure, from Jason Baron. 9) Remove several old and unused ISDN drivers, from Arnd Bergmann. 10) Add devlink notifications for flash update status to mlxsw driver, from Jiri Pirko. 11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski. 12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes. 13) Various enhancements to ipv6 flow label handling, from Eric Dumazet and Willem de Bruijn. 14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van der Merwe, and others. 15) Various improvements to axienet driver including converting it to phylink, from Robert Hancock. 16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean. 17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana Radulescu. 18) Add devlink health reporting to mlx5, from Moshe Shemesh. 19) Convert stmmac over to phylink, from Jose Abreu. 20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from Shalom Toledo. 21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera. 22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel. 23) Track spill/fill of constants in BPF verifier, from Alexei Starovoitov. 24) Support bounded loops in BPF, from Alexei Starovoitov. 25) Various page_pool API fixes and improvements, from Jesper Dangaard Brouer. 26) Just like ipv4, support ref-countless ipv6 route handling. From Wei Wang. 27) Support VLAN offloading in aquantia driver, from Igor Russkikh. 28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy. 29) Add flower GRE encap/decap support to nfp driver, from Pieter Jansen van Vuuren. 30) Protect against stack overflow when using act_mirred, from John Hurley. 31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen. 32) Use page_pool API in netsec driver, Ilias Apalodimas. 33) Add Google gve network driver, from Catherine Sullivan. 34) More indirect call avoidance, from Paolo Abeni. 35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan. 36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek. 37) Add MPLS manipulation actions to TC, from John Hurley. 38) Add sending a packet to connection tracking from TC actions, and then allow flower classifier matching on conntrack state. From Paul Blakey. 39) Netfilter hw offload support, from Pablo Neira Ayuso" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits) net/mlx5e: Return in default case statement in tx_post_resync_params mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync(). net: dsa: add support for BRIDGE_MROUTER attribute pkt_sched: Include const.h net: netsec: remove static declaration for netsec_set_tx_de() net: netsec: remove superfluous if statement netfilter: nf_tables: add hardware offload support net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload net: flow_offload: add flow_block_cb_is_busy() and use it net: sched: remove tcf block API drivers: net: use flow block API net: sched: use flow block API net: flow_offload: add flow_block_cb_{priv, incref, decref}() net: flow_offload: add list handling functions net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free() net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_* net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND net: flow_offload: add flow_block_cb_setup_simple() net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC ...
2019-07-09Merge tag 'docs-5.3' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull Documentation updates from Jonathan Corbet: "It's been a relatively busy cycle for docs: - A fair pile of RST conversions, many from Mauro. These create more than the usual number of simple but annoying merge conflicts with other trees, unfortunately. He has a lot more of these waiting on the wings that, I think, will go to you directly later on. - A new document on how to use merges and rebases in kernel repos, and one on Spectre vulnerabilities. - Various improvements to the build system, including automatic markup of function() references because some people, for reasons I will never understand, were of the opinion that :c:func:``function()`` is unattractive and not fun to type. - We now recommend using sphinx 1.7, but still support back to 1.4. - Lots of smaller improvements, warning fixes, typo fixes, etc" * tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits) docs: automarkup.py: ignore exceptions when seeking for xrefs docs: Move binderfs to admin-guide Disable Sphinx SmartyPants in HTML output doc: RCU callback locks need only _bh, not necessarily _irq docs: format kernel-parameters -- as code Doc : doc-guide : Fix a typo platform: x86: get rid of a non-existent document Add the RCU docs to the core-api manual Documentation: RCU: Add TOC tree hooks Documentation: RCU: Rename txt files to rst Documentation: RCU: Convert RCU UP systems to reST Documentation: RCU: Convert RCU linked list to reST Documentation: RCU: Convert RCU basic concepts to reST docs: filesystems: Remove uneeded .rst extension on toctables scripts/sphinx-pre-install: fix out-of-tree build docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/ Documentation: PGP: update for newer HW devices Documentation: Add section about CPU vulnerabilities for Spectre Documentation: platform: Delete x86-laptop-drivers.txt docs: Note that :c:func: should no longer be used ...
2019-07-09ipv6: elide flowlabel check if no exclusive leases existWillem de Bruijn4-9/+28
Processes can request ipv6 flowlabels with cmsg IPV6_FLOWINFO. If not set, by default an autogenerated flowlabel is selected. Explicit flowlabels require a control operation per label plus a datapath check on every connection (every datagram if unconnected). This is particularly expensive on unconnected sockets multiplexing many flows, such as QUIC. In the common case, where no lease is exclusive, the check can be safely elided, as both lease request and check trivially succeed. Indeed, autoflowlabel does the same even with exclusive leases. Elide the check if no process has requested an exclusive lease. fl6_sock_lookup previously returns either a reference to a lease or NULL to denote failure. Modify to return a real error and update all callers. On return NULL, they can use the label and will elide the atomic_dec in fl6_sock_release. This is an optimization. Robust applications still have to revert to requesting leases if the fast path fails due to an exclusive lease. Changes RFC->v1: - use static_key_false_deferred to rate limit jump label operations - call static_key_deferred_flush to stop timers on exit - move decrement out of RCU context - defer optimization also if opt data is associated with a lease - updated all fp6_sock_lookup callers, not just udp Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-09ipv6: Support multipath hashing on inner IP pktsStephen Suryaputra1-0/+36
Make the same support as commit 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts for GRE tunnel") for outer IPv6. The hashing considers both IPv4 and IPv6 pkts when they are tunneled by IPv6 GRE. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-06net: remove unused parameter from skb_checksum_try_convertLi RongQing1-2/+1
the check parameter is never used Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-06Merge branch 'master' of ↵David S. Miller6-170/+7
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2019-07-05 1) A lot of work to remove indirections from the xfrm code. From Florian Westphal. 2) Fix a WARN_ON with ipv6 that triggered because of a forgotten break statement. From Florian Westphal. 3) Remove xfrmi_init_net, it is not needed. From Li RongQing. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-03ipv6: use indirect call wrappers for {tcp, udpv6}_{recv, send}msg()Paolo Abeni1-3/+9
This avoids an indirect call per syscall for common ipv6 transports Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-03ipv6: provide and use ipv6 specific version for {recv, send}msgPaolo Abeni1-4/+31
This will simplify indirect call wrapper invocation in the following patch. No functional change intended, any - out-of-tree - IPv6 user of inet_{recv,send}msg can keep using the existing functions. SCTP code still uses the existing version even for ipv6: as this series will not add ICW for SCTP, moving to the new helper would not give any benefit. The only other in-kernel user of inet_{recv,send}msg is pvcalls_conn_back_read(), but psvcalls explicitly creates only IPv4 socket, so no need to update that code path, too. v1 -> v2: drop inet6_{recv,send}msg declaration from header file, prefer ICW macro instead Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-02blackhole_netdev: use blackhole_netdev to invalidate dst entriesMahesh Bandewar1-1/+1
Use blackhole_netdev instead of 'lo' device with lower MTU when marking dst "dead". Signed-off-by: Mahesh Bandewar <maheshb@google.com> Tested-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-02net/ipv6: Fix misuse of proc_dointvec "flowlabel_reflect"Eiichi Tsukata1-1/+1
/proc/sys/net/ipv6/flowlabel_reflect assumes written value to be in the range of 0 to 3. Use proc_dointvec_minmax instead of proc_dointvec. Fixes: 323a53c41292 ("ipv6: tcp: enable flowlabel reflection in some RST packets") Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: David S. Miller <davem@davemloft.net>