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* tcp: avoid two atomic ops for syncookiesEric Dumazet2015-10-05
| | | | | | | | | | | | inet_reqsk_alloc() is used to allocate a temporary request in order to generate a SYNACK with a cookie. Then later, syncookie validation also uses a temporary request. These paths already took a reference on listener refcount, we can avoid a couple of atomic operations. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: fix fastopen races vs lockless listenerEric Dumazet2015-10-05
| | | | | | | | | | | | | | | | | | | | | | There are multiple races that need fixes : 1) skb_get() + queue skb + kfree_skb() is racy An accept() can be done on another cpu, data consumed immediately. tcp_recvmsg() uses __kfree_skb() as it is assumed all skb found in socket receive queue are private. Then the kfree_skb() in tcp_rcv_state_process() uses an already freed skb 2) tcp_reqsk_record_syn() needs to be done before tcp_try_fastopen() for the same reasons. 3) We want to send the SYNACK before queueing child into accept queue, otherwise we might reintroduce the ooo issue fixed in commit 7c85af881044 ("tcp: avoid reorders for TFO passive connections") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: do not lock listener to process SYN packetsEric Dumazet2015-10-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Everything should now be ready to finally allow SYN packets processing without holding listener lock. Tested: 3.5 Mpps SYNFLOOD. Plenty of cpu cycles available. Next bottleneck is the refcount taken on listener, that could be avoided if we remove SLAB_DESTROY_BY_RCU strict semantic for listeners, and use regular RCU. 13.18% [kernel] [k] __inet_lookup_listener 9.61% [kernel] [k] tcp_conn_request 8.16% [kernel] [k] sha_transform 5.30% [kernel] [k] inet_reqsk_alloc 4.22% [kernel] [k] sock_put 3.74% [kernel] [k] tcp_make_synack 2.88% [kernel] [k] ipt_do_table 2.56% [kernel] [k] memcpy_erms 2.53% [kernel] [k] sock_wfree 2.40% [kernel] [k] tcp_v4_rcv 2.08% [kernel] [k] fib_table_lookup 1.84% [kernel] [k] tcp_openreq_init_rwin Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: add a reschedule point in inet_csk_listen_stop()Eric Dumazet2015-10-03
| | | | | | | | If a listener with thousands of children in accept queue is dismantled, it can take a while to close all of them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: remove max_qlen_logEric Dumazet2015-10-03
| | | | | | | | | | | | This control variable was set at first listen(fd, backlog) call, but not updated if application tried to increase or decrease backlog. It made sense at the time listener had a non resizeable hash table. Also rounding to powers of two was not very friendly. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: remove struct listen_sockEric Dumazet2015-10-03
| | | | | | | | | | | | It is enough to check listener sk_state, no need for an extra condition. max_qlen_log can be moved into struct request_sock_queue We can remove syn_wait_lock and the alignment it enforced. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: attach SYNACK messages to request sockets instead of listenerEric Dumazet2015-10-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a listen backlog is very big (to avoid syncookies), then the listener sk->sk_wmem_alloc is the main source of false sharing, as we need to touch it twice per SYNACK re-transmit and TX completion. (One SYN packet takes listener lock once, but up to 6 SYNACK are generated) By attaching the skb to the request socket, we remove this source of contention. Tested: listen(fd, 10485760); // single listener (no SO_REUSEPORT) 16 RX/TX queue NIC Sustain a SYNFLOOD attack of ~320,000 SYN per second, Sending ~1,400,000 SYNACK per second. Perf profiles now show listener spinlock being next bottleneck. 20.29% [kernel] [k] queued_spin_lock_slowpath 10.06% [kernel] [k] __inet_lookup_established 5.12% [kernel] [k] reqsk_timer_handler 3.22% [kernel] [k] get_next_timer_interrupt 3.00% [kernel] [k] tcp_make_synack 2.77% [kernel] [k] ipt_do_table 2.70% [kernel] [k] run_timer_softirq 2.50% [kernel] [k] ip_finish_output 2.04% [kernel] [k] cascade Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: install syn_recv requests into ehash tableEric Dumazet2015-10-03
| | | | | | | | | | | | | | | | | | | | | | | | In this patch, we insert request sockets into TCP/DCCP regular ehash table (where ESTABLISHED and TIMEWAIT sockets are) instead of using the per listener hash table. ACK packets find SYN_RECV pseudo sockets without having to find and lock the listener. In nominal conditions, this halves pressure on listener lock. Note that this will allow for SO_REUSEPORT refinements, so that we can select a listener using cpu/numa affinities instead of the prior 'consistent hash', since only SYN packets will apply this selection logic. We will shrink listen_sock in the following patch to ease code review. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ying Cai <ycai@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: remove inet_csk_reqsk_queue_added() timeout argumentEric Dumazet2015-10-03
| | | | | | | This is no longer used. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: get_openreq[46]() changesEric Dumazet2015-10-03
| | | | | | | | | | | When request sockets are no longer in a per listener hash table but on regular TCP ehash, we need to access listener uid through req->rsk_listener get_openreq6() also gets a const for its request socket argument. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: remove BUG_ON() in tcp_check_req()Eric Dumazet2015-10-03
| | | | | | | Once listener is lockless, its sk_state can change anytime. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: cleanup tcp_v[46]_inbound_md5_hash()Eric Dumazet2015-10-03
| | | | | | | | | We'll soon have to call tcp_v[46]_inbound_md5_hash() twice. Also add const attribute to the socket, as it might be the unlocked listener for SYN packets. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: call sk_mark_napi_id() on the child, not the listenerEric Dumazet2015-10-03
| | | | | | | | | This fixes a typo : We want to store the NAPI id on child socket. Presumably nobody really uses busy polling, on short lived flows. Fixes: 3d97379a67486 ("tcp: move sk_mark_napi_id() at the right place") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: move synflood_warned into struct request_sock_queueEric Dumazet2015-10-03
| | | | | | | | long term plan is to remove struct listen_sock when its hash table is no longer there. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: move qlen/young out of struct listen_sockEric Dumazet2015-10-03
| | | | | | | | | | | | | qlen_inc & young_inc were protected by listener lock, while qlen_dec & young_dec were atomic fields. Everything needs to be atomic for upcoming lockless listener. Also move qlen/young in request_sock_queue as we'll get rid of struct listen_sock eventually. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: add a spinlock to protect struct request_sock_queueEric Dumazet2015-10-03
| | | | | | | | | | | | struct request_sock_queue fields are currently protected by the listener 'lock' (not a real spinlock) We need to add a private spinlock instead, so that softirq handlers creating children do not have to worry with backlog notion that the listener 'lock' carries. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-10-02
|\ | | | | | | | | | | | | | | | | Conflicts: net/dsa/slave.c net/dsa/slave.c simply had overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: Initialize flow flags in input pathDavid Ahern2015-09-29
| | | | | | | | | | | | | | | | The fib_table_lookup tracepoint found 2 places where the flowi4_flags is not initialized. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller2015-09-29
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following pull request contains Netfilter/IPVS updates for net-next containing 90 patches from Eric Biederman. The main goal of this batch is to avoid recurrent lookups for the netns pointer, that happens over and over again in our Netfilter/IPVS code. The idea consists of passing netns pointer from the hook state to the relevant functions and objects where this may be needed. You can find more information on the IPVS updates from Simon Horman's commit merge message: c3456026adc0 ("Merge tag 'ipvs2-for-v4.4' of https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-next"). Exceptionally, this time, I'm not posting the patches again on netdev, Eric already Cc'ed this mailing list in the original submission. If you need me to make, just let me know. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ipv4: Pass struct net into ip_route_me_harderEric W. Biederman2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | Don't make ip_route_me_harder guess which network namespace it is routing in, pass the network namespace in. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| * | netfilter: ipt_SYNPROXY: Pass snet into synproxy_send_tcpEric W. Biederman2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ip6t_SYNPROXY already does this and this is needed so that we have a struct net that can be passed down into ip_route_me_harder, so that ip_route_me_harder can stop guessing it's context. Along the way pass snet into synproxy_send_client_synack as this is the only caller of synprox_send_tcp that is not passed snet already. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| * | netfilter: Push struct net down into nf_afinfo.rerouteEric W. Biederman2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | The network namespace is needed when routing a packet. Stop making nf_afinfo.reroute guess which network namespace is the proper namespace to route the packet in. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| * | ipv4: Push struct net down into nf_send_resetEric W. Biederman2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | This is needed so struct net can be pushed down into ip_route_me_harder. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* | | net: Replace calls to vrf_dev_get_rthDavid Ahern2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | Replace calls to vrf_dev_get_rth with l3mdev_get_rtable. The check on the flow flags is handled in the l3mdev operation. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Replace vrf_dev_table and friendsDavid Ahern2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | Replace calls to vrf_dev_table and friends with l3mdev_fib_table and kin. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Replace vrf_master_ifindex{, _rcu} with l3mdev equivalentsDavid Ahern2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace calls to vrf_master_ifindex_rcu and vrf_master_ifindex with either l3mdev_master_ifindex_rcu or l3mdev_master_ifindex. The pattern: oif = vrf_master_ifindex(dev) ? : dev->ifindex; is replaced with oif = l3mdev_fib_oif(dev); And remove the now unused vrf macros. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Rename IFF_VRF_MASTER to IFF_L3MDEV_MASTERDavid Ahern2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | Rename IFF_VRF_MASTER to IFF_L3MDEV_MASTER and update the name of the netif_is_vrf and netif_index_is_vrf macros. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: prepare fastopen code for upcoming listener changesEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While auditing TCP stack for upcoming 'lockless' listener changes, I found I had to change fastopen_init_queue() to properly init the object before publishing it. Otherwise an other cpu could try to lock the spinlock before it gets properly initialized. Instead of adding appropriate barriers, just remove dynamic memory allocations : - Structure is 28 bytes on 64bit arches. Using additional 8 bytes for holding a pointer seems overkill. - Two listeners can share same cache line and performance would suffer. If we really want to save few bytes, we would instead dynamically allocate whole struct request_sock_queue in the future. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: constify tcp_syn_flood_action() socket argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tcp_syn_flood_action() will soon be called with unlocked socket. In order to avoid SYN flood warning being emitted multiple times, use xchg(). Extend max_qlen_log and synflood_warned fields in struct listen_sock to u32 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: constify tcp_v{4|6}_route_req() sock argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | These functions do not change the listener socket. Goal is to make sure tcp_conn_request() is not messing with listener in a racy way. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: cookie_init_sequence() cleanupsEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | Some common IPv4/IPv6 code can be factorized. Also constify cookie_init_sequence() socket argument. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp/dccp: constify syn_recv_sock() method sock argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | We'll soon no longer hold listener socket lock, these functions do not modify the socket in any way. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: constify tcp_create_openreq_child() socket argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | This method does not touch the listener socket. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | inet: constify __inet_inherit_port() sock argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | socket is not touched, make it const. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | inet: constify inet_csk_route_child_sock() socket argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | The socket points to the (shared) listener. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: remove tcp_rcv_state_process() tcp_hdr argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | Factorize code to get tcp header from skb. It makes no sense to duplicate code in callers. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: remove unused len argument from tcp_rcv_state_process()Eric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | Once we realize tcp_rcv_synsent_state_process() does not use its 'len' argument and we get rid of it, then it becomes clear this argument is no longer used in tcp_rcv_state_process() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp/dccp: constify send_synack and send_reset socket argumentEric Dumazet2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | None of these functions need to change the socket, make it const. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Remove martian_source_keep_err goto labelDavid Ahern2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | err is initialized to -EINVAL when it is declared. It is not reset until fib_lookup which is well after the 3 users of the martian_source jump. So resetting err to -EINVAL at martian_source label is not needed. Removing that line obviates the need for the martian_source_keep_err label so delete it. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: Swap ordering of tests in ip_route_input_mcAlexander Duyck2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch just swaps the ordering of one of the conditional tests in ip_route_input_mc. Specifically it swaps the testing for the source address to see if it is loopback, and the test to see if we allow a loopback source address. The reason for swapping these two tests is because it is much faster to test if an address is loopback than it is to dereference several pointers to get at the net structure to see if the use of loopback is allowed. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net/ipv4: Pass proto as u8 instead of u16 in ip_check_mc_rcuAlexander Duyck2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates ip_check_mc_rcu so that protocol is passed as a u8 instead of a u16. The motivation is just to avoid any unneeded type transitions since some systems will require an instruction to zero extend a u8 field to a u16. Also it makes it a bit more readable as to the fact that protocol is a u8 so there are no byte ordering changes needed to pass it. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: Fix CWV being too strict on thin streamsBendik Rønning Opstad2015-09-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Application limited streams such as thin streams, that transmit small amounts of payload in relatively few packets per RTT, can be prevented from growing the CWND when in congestion avoidance. This leads to increased sojourn times for data segments in streams that often transmit time-dependent data. Currently, a connection is considered CWND limited only after having successfully transmitted at least one packet with new data, while at the same time failing to transmit some unsent data from the output queue because the CWND is full. Applications that produce small amounts of data may be left in a state where it is never considered to be CWND limited, because all unsent data is successfully transmitted each time an incoming ACK opens up for more data to be transmitted in the send window. Fix by always testing whether the CWND is fully used after successful packet transmissions, such that a connection is considered CWND limited whenever the CWND has been filled. This is the correct behavior as specified in RFC2861 (section 3.1). Cc: Andreas Petlund <apetlund@simula.no> Cc: Carsten Griwodz <griff@simula.no> Cc: Jonas Markussen <jonassm@ifi.uio.no> Cc: Kenneth Klette Jonassen <kennetkl@ifi.uio.no> Cc: Mads Johannessen <madsjoh@ifi.uio.no> Signed-off-by: Bendik Rønning Opstad <bro.devel+kernel@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Tested-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | tcp: avoid reorders for TFO passive connectionsEric Dumazet2015-09-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We found that a TCP Fast Open passive connection was vulnerable to reorders, as the exchange might look like [1] C -> S S <FO ...> <request> [2] S -> C S. ack request <options> [3] S -> C . <answer> packets [2] and [3] can be generated at almost the same time. If C receives the 3rd packet before the 2nd, it will drop it as the socket is in SYN_SENT state and expects a SYNACK. S will have to retransmit the answer. Current OOO avoidance in linux is defeated because SYNACK packets are attached to the LISTEN socket, while DATA packets are attached to the children. They might be sent by different cpus, and different TX queues might be selected. It turns out that for TFO, we created a child, which is a full blown socket in TCP_SYN_RECV state, and we simply can attach the SYNACK packet to this socket. This means that at the time tcp_sendmsg() pushes DATA packet, skb->ooo_okay will be set iff the SYNACK packet had been sent and TX completed. This removes the reorder source at the host level. We also removed the export of tcp_try_fastopen(), as it is no longer called from IPv6. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-09-26
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | Conflicts: net/ipv4/arp.c The net/ipv4/arp.c conflict was one commit adding a new local variable while another commit was deleting one. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: Fix panic in icmp_route_lookupDavid Ahern2015-09-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andrey reported a panic: [ 7249.865507] BUG: unable to handle kernel pointer dereference at 000000b4 [ 7249.865559] IP: [<c16afeca>] icmp_route_lookup+0xaa/0x320 [ 7249.865598] *pdpt = 0000000030f7f001 *pde = 0000000000000000 [ 7249.865637] Oops: 0000 [#1] ... [ 7249.866811] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.3.0-999-generic #201509220155 [ 7249.866876] Hardware name: MSI MS-7250/MS-7250, BIOS 080014 08/02/2006 [ 7249.866916] task: c1a5ab00 ti: c1a52000 task.ti: c1a52000 [ 7249.866949] EIP: 0060:[<c16afeca>] EFLAGS: 00210246 CPU: 0 [ 7249.866981] EIP is at icmp_route_lookup+0xaa/0x320 [ 7249.867012] EAX: 00000000 EBX: f483ba48 ECX: 00000000 EDX: f2e18a00 [ 7249.867045] ESI: 000000c0 EDI: f483ba70 EBP: f483b9ec ESP: f483b974 [ 7249.867077] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [ 7249.867108] CR0: 8005003b CR2: 000000b4 CR3: 36ee07c0 CR4: 000006f0 [ 7249.867141] Stack: [ 7249.867165] 320310ee 00000000 00000042 320310ee 00000000 c1aeca00 f3920240 f0c69180 [ 7249.867268] f483ba04 f855058b a89b66cd f483ba44 f8962f4b 00000000 e659266c f483ba54 [ 7249.867361] 8004753c f483ba5c f8962f4b f2031140 000003c1 ffbd8fa0 c16b0e00 00000064 [ 7249.867448] Call Trace: [ 7249.867494] [<f855058b>] ? e1000_xmit_frame+0x87b/0xdc0 [e1000e] [ 7249.867534] [<f8962f4b>] ? tcp_in_window+0xeb/0xb10 [nf_conntrack] [ 7249.867576] [<f8962f4b>] ? tcp_in_window+0xeb/0xb10 [nf_conntrack] [ 7249.867615] [<c16b0e00>] ? icmp_send+0xa0/0x380 [ 7249.867648] [<c16b102f>] icmp_send+0x2cf/0x380 [ 7249.867681] [<f89c8126>] nf_send_unreach+0xa6/0xc0 [nf_reject_ipv4] [ 7249.867714] [<f89cd0da>] reject_tg+0x7a/0x9f [ipt_REJECT] [ 7249.867746] [<f88c29a7>] ipt_do_table+0x317/0x70c [ip_tables] [ 7249.867780] [<f895e0a6>] ? __nf_conntrack_find_get+0x166/0x3b0 [nf_conntrack] [ 7249.867838] [<f895eea8>] ? nf_conntrack_in+0x398/0x600 [nf_conntrack] [ 7249.867889] [<f84c0035>] iptable_filter_hook+0x35/0x80 [iptable_filter] [ 7249.867933] [<c16776a1>] nf_iterate+0x71/0x80 [ 7249.867970] [<c1677715>] nf_hook_slow+0x65/0xc0 [ 7249.868002] [<c1681811>] __ip_local_out_sk+0xc1/0xd0 [ 7249.868034] [<c1680f30>] ? ip_forward_options+0x1a0/0x1a0 [ 7249.868066] [<c1681836>] ip_local_out_sk+0x16/0x30 [ 7249.868097] [<c1684054>] ip_send_skb+0x14/0x80 [ 7249.868129] [<c16840f4>] ip_push_pending_frames+0x34/0x40 [ 7249.868163] [<c16844a2>] ip_send_unicast_reply+0x282/0x310 [ 7249.868196] [<c16a0863>] tcp_v4_send_reset+0x1b3/0x380 [ 7249.868227] [<c16a1b63>] tcp_v4_rcv+0x323/0x990 [ 7249.868257] [<c16776a1>] ? nf_iterate+0x71/0x80 [ 7249.868289] [<c167dc2b>] ip_local_deliver_finish+0x8b/0x230 [ 7249.868322] [<c167df4c>] ip_local_deliver+0x4c/0xa0 [ 7249.868353] [<c167dba0>] ? ip_rcv_finish+0x390/0x390 [ 7249.868384] [<c167d88c>] ip_rcv_finish+0x7c/0x390 [ 7249.868415] [<c167e280>] ip_rcv+0x2e0/0x420 ... Prior to the VRF change the oif was not set in the flow struct, so the VRF support should really have only added the vrf_master_ifindex lookup. Fixes: 613d09b30f8b ("net: Use VRF device index for lookups on TX") Cc: Andrey Melnikov <temnota.am@gmail.com> Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | lwtunnel: remove source and destination UDP port config optionJiri Benc2015-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The UDP tunnel config is asymmetric wrt. to the ports used. The source and destination ports from one direction of the tunnel are not related to the ports of the other direction. We need to be able to respond to ARP requests using the correct ports without involving routing. As the consequence, UDP ports need to be fixed property of the tunnel interface and cannot be set per route. Remove the ability to set ports per route. This is still okay to do, as no kernel has been released with these attributes yet. Note that the ability to specify source and destination ports is preserved for other users of the lwtunnel API which don't use routes for tunnel key specification (like openvswitch). If in the future we rework ARP handling to allow port specification, the attributes can be added back. Signed-off-by: Jiri Benc <jbenc@redhat.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ipv4: send arp replies to the correct tunnelJiri Benc2015-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When using ip lwtunnels, the additional data for xmit (basically, the actual tunnel to use) are carried in ip_tunnel_info either in dst->lwtstate or in metadata dst. When replying to ARP requests, we need to send the reply to the same tunnel the request came from. This means we need to construct proper metadata dst for ARP replies. We could perform another route lookup to get a dst entry with the correct lwtstate. However, this won't always ensure that the outgoing tunnel is the same as the incoming one, and it won't work anyway for IPv4 duplicate address detection. The only thing to do is to "reverse" the ip_tunnel_info. Signed-off-by: Jiri Benc <jbenc@redhat.com> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp: add proper TS val into RST packetsEric Dumazet2015-09-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RST packets sent on behalf of TCP connections with TS option (RFC 7323 TCP timestamps) have incorrect TS val (set to 0), but correct TS ecr. A > B: Flags [S], seq 0, win 65535, options [mss 1000,nop,nop,TS val 100 ecr 0], length 0 B > A: Flags [S.], seq 2444755794, ack 1, win 28960, options [mss 1460,nop,nop,TS val 7264344 ecr 100], length 0 A > B: Flags [.], ack 1, win 65535, options [nop,nop,TS val 110 ecr 7264344], length 0 B > A: Flags [R.], seq 1, ack 1, win 28960, options [nop,nop,TS val 0 ecr 110], length 0 We need to call skb_mstamp_get() to get proper TS val, derived from skb->skb_mstamp Note that RFC 1323 was advocating to not send TS option in RST segment, but RFC 7323 recommends the opposite : Once TSopt has been successfully negotiated, that is both <SYN> and <SYN,ACK> contain TSopt, the TSopt MUST be sent in every non-<RST> segment for the duration of the connection, and SHOULD be sent in an <RST> segment (see Section 5.2 for details) Note this RFC recommends to send TS val = 0, but we believe it is premature : We do not know if all TCP stacks are properly handling the receive side : When an <RST> segment is received, it MUST NOT be subjected to the PAWS check by verifying an acceptable value in SEG.TSval, and information from the Timestamps option MUST NOT be used to update connection state information. SEG.TSecr MAY be used to provide stricter <RST> acceptance checks. In 5 years, if/when all TCP stack are RFC 7323 ready, we might consider to decide to send TS val = 0, if it buys something. Fixes: 7faee5c0d514 ("tcp: remove TCP_SKB_CB(skb)->when") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | inet: fix races in reqsk_queue_hash_req()Eric Dumazet2015-09-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before allowing lockless LISTEN processing, we need to make sure to arm the SYN_RECV timer before the req socket is visible in hash tables. Also, req->rsk_hash should be written before we set rsk_refcnt to a non zero value. Fixes: fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ying Cai <ycai@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp/dccp: fix timewait races in timer handlingEric Dumazet2015-09-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When creating a timewait socket, we need to arm the timer before allowing other cpus to find it. The signal allowing cpus to find the socket is setting tw_refcnt to non zero value. As we set tw_refcnt in __inet_twsk_hashdance(), we therefore need to call inet_twsk_schedule() first. This also means we need to remove tw_refcnt changes from inet_twsk_schedule() and let the caller handle it. Note that because we use mod_timer_pinned(), we have the guarantee the timer wont expire before we set tw_refcnt as we run in BH context. To make things more readable I introduced inet_twsk_reschedule() helper. When rearming the timer, we can use mod_timer_pending() to make sure we do not rearm a canceled timer. Note: This bug can possibly trigger if packets of a flow can hit multiple cpus. This does not normally happen, unless flow steering is broken somehow. This explains this bug was spotted ~5 months after its introduction. A similar fix is needed for SYN_RECV sockets in reqsk_queue_hash_req(), but will be provided in a separate patch for proper tracking. Fixes: 789f558cfb36 ("tcp/dccp: get rid of central timewait timer") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Ying Cai <ycai@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>