linux/net/netfilter
Julian Anastasov f719e3754e ipvs: drop first packet to redirect conntrack
Jiri Bohac is reporting for a problem where the attempt
to reschedule existing connection to another real server
needs proper redirect for the conntrack used by the IPVS
connection. For example, when IPVS connection is created
to NAT-ed real server we alter the reply direction of
conntrack. If we later decide to select different real
server we can not alter again the conntrack. And if we
expire the old connection, the new connection is left
without conntrack.

So, the only way to redirect both the IPVS connection and
the Netfilter's conntrack is to drop the SYN packet that
hits existing connection, to wait for the next jiffie
to expire the old connection and its conntrack and to rely
on client's retransmission to create new connection as
usually.

Jiri Bohac provided a fix that drops all SYNs on rescheduling,
I extended his patch to do such drops only for connections
that use conntrack. Here is the original report from Jiri Bohac:

Since commit dc7b3eb900 ("ipvs: Fix reuse connection if real server
is dead"), new connections to dead servers are redistributed
immediately to new servers.  The old connection is expired using
ip_vs_conn_expire_now() which sets the connection timer to expire
immediately.

However, before the timer callback, ip_vs_conn_expire(), is run
to clean the connection's conntrack entry, the new redistributed
connection may already be established and its conntrack removed
instead.

Fix this by dropping the first packet of the new connection
instead, like we do when the destination server is not available.
The timer will have deleted the old conntrack entry long before
the first packet of the new connection is retransmitted.

Fixes: dc7b3eb900 ("ipvs: Fix reuse connection if real server is dead")
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2016-03-07 11:53:30 +09:00
..
ipset netfilter: ipset: allow a 0 netmask with hash_netiface type 2016-01-13 14:03:43 +01:00
ipvs ipvs: drop first packet to redirect conntrack 2016-03-07 11:53:30 +09:00
core.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-24 06:54:12 -07:00
Kconfig netfilter: tee: select NF_DUP_IPV6 unconditionally 2016-02-08 12:58:28 +01:00
Makefile netfilter: nf_tables: add forward expression to the netdev family 2016-01-04 17:48:38 +01:00
nf_conntrack_acct.c netfilter: Remove uses of seq_<foo> return values 2015-03-18 10:51:35 +01:00
nf_conntrack_amanda.c net: Remove state argument from skb_find_text() 2015-02-22 15:59:54 -05:00
nf_conntrack_broadcast.c
nf_conntrack_core.c netfilter: conntrack: resched in nf_ct_iterate_cleanup 2016-02-01 00:15:26 +01:00
nf_conntrack_ecache.c netfilter: conntrack: remove timer from ecache extension 2014-06-25 19:15:38 +02:00
nf_conntrack_expect.c netfilter: Set /proc/net entries owner to root in namespace 2015-11-25 13:54:09 +01:00
nf_conntrack_extend.c
nf_conntrack_ftp.c netfilter: nf_ct_helper: define pr_fmt() 2016-01-04 17:48:51 +01:00
nf_conntrack_h323_asn1.c
nf_conntrack_h323_main.c ipv6: Remove external dependency on rt6i_gateway and RTF_ANYCAST 2015-05-25 13:25:33 -04:00
nf_conntrack_h323_types.c
nf_conntrack_helper.c netfilter: nf_conntrack: use safer way to lock all buckets 2016-01-20 14:15:31 +01:00
nf_conntrack_irc.c netfilter: nf_ct_helper: define pr_fmt() 2016-01-04 17:48:51 +01:00
nf_conntrack_l3proto_generic.c netfilter: Convert print_tuple functions to return void 2014-11-05 14:10:33 -05:00
nf_conntrack_labels.c netfilter: connlabels: Export setting connlabel length 2015-08-27 11:40:43 -07:00
nf_conntrack_netbios_ns.c
nf_conntrack_netlink.c netfilter: nf_conntrack: use safer way to lock all buckets 2016-01-20 14:15:31 +01:00
nf_conntrack_pptp.c netfilter: nf_conntrack: push zone object into functions 2015-08-11 12:29:01 +02:00
nf_conntrack_proto_dccp.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto_generic.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto_gre.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto_sctp.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto_tcp.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto_udp.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto_udplite.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
nf_conntrack_proto.c netfilter: nf_conntrack: remove dead code 2014-01-03 23:41:37 +01:00
nf_conntrack_sane.c netfilter: nf_ct_helper: define pr_fmt() 2016-01-04 17:48:51 +01:00
nf_conntrack_seqadj.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
nf_conntrack_sip.c netfilter: nf_ct_helper: define pr_fmt() 2016-01-04 17:48:51 +01:00
nf_conntrack_snmp.c
nf_conntrack_standalone.c netfilter: Set /proc/net entries owner to root in namespace 2015-11-25 13:54:09 +01:00
nf_conntrack_tftp.c netfilter: nf_ct_helper: define pr_fmt() 2016-01-04 17:48:51 +01:00
nf_conntrack_timeout.c netfilter: cttimeout: add netns support 2015-12-14 12:48:58 +01:00
nf_conntrack_timestamp.c netfilter: nf_ct_timestamp: Fix BUG_ON after netns deletion 2013-12-20 14:58:29 +01:00
nf_dup_netdev.c netfilter: nf_tables: add packet duplication to the netdev family 2016-01-03 21:04:23 +01:00
nf_internals.h netfilter: nf_queue: fix nf_queue_nf_hook_drop() 2015-07-23 16:17:58 +02:00
nf_log_common.c netfilter: bridge: add helpers for fetching physin/outdev 2015-04-08 16:49:08 +02:00
nf_log.c netfilter: nf_log: wait for rcu grace after logger unregistration 2015-09-17 13:37:31 +02:00
nf_nat_amanda.c
nf_nat_core.c netfilter: Pass net into nf_xfrm_me_harder 2015-09-18 22:00:22 +02:00
nf_nat_ftp.c
nf_nat_helper.c netfilter: nf_conntrack: make sequence number adjustments usuable without NAT 2013-08-28 00:26:48 +02:00
nf_nat_irc.c netfilter: nf_nat: fix access to uninitialized buffer in IRC NAT helper 2014-01-06 14:17:17 +01:00
nf_nat_proto_common.c netfilter: use IS_ENABLED() macro 2014-06-30 11:38:03 +02:00
nf_nat_proto_dccp.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
nf_nat_proto_sctp.c netfilter: use IS_ENABLED() macro 2014-06-30 11:38:03 +02:00
nf_nat_proto_tcp.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
nf_nat_proto_udp.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
nf_nat_proto_udplite.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
nf_nat_proto_unknown.c
nf_nat_redirect.c netfilter: nf_nat_redirect: add missing NULL pointer check 2015-10-27 06:54:56 +01:00
nf_nat_sip.c netfilter: replace strnicmp with strncasecmp 2014-10-14 02:18:24 +02:00
nf_nat_tftp.c
nf_queue.c netfilter: nf_queue: remove rcu_read_lock calls 2015-10-16 18:22:41 +02:00
nf_sockopt.c netfilter: don't use mutex_lock_interruptible() 2014-08-08 16:47:23 +02:00
nf_synproxy_core.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2015-09-05 21:57:42 -07:00
nf_tables_api.c netfilter: nf_tables: Add new attributes into nft_set to store user data. 2016-01-08 13:25:08 +01:00
nf_tables_core.c netfilter: nf_tables: fix nf_log_trace based tracing 2015-12-09 16:53:46 +01:00
nf_tables_inet.c netfilter: nf_tables: release objects on netns destruction 2015-12-28 18:34:35 +01:00
nf_tables_netdev.c netfilter: nf_tables_netdev: fix error path in module initialization 2016-01-18 13:53:37 +01:00
nf_tables_trace.c netfilter: nf_tables: wrap tracing with a static key 2015-12-09 13:23:13 +01:00
nfnetlink_acct.c netfilter: nfnetlink_acct: validate NFACCT_FILTER parameters 2016-02-29 13:27:21 +01:00
nfnetlink_cthelper.c netfilter: nfnetlink: pass down netns pointer to call() and call_rcu() 2015-12-28 18:41:41 +01:00
nfnetlink_cttimeout.c netfilter: cttimeout: fix deadlock due to erroneous unlock/lock conversion 2016-02-01 00:15:28 +01:00
nfnetlink_log.c netfilter: nfnetlink_log: just returns error for unknown command 2016-01-08 13:25:07 +01:00
nfnetlink_queue.c netfilter: nfnetlink_queue: autoload nf_conntrack_netlink module NFQA_CFG_F_CONNTRACK config flag 2016-01-08 13:25:06 +01:00
nfnetlink.c netfilter: nfnetlink: correctly validate length of batch messages 2016-02-08 12:56:54 +01:00
nft_bitwise.c netfilter: nf_tables: support variable sized data in nft_data_init() 2015-04-13 17:17:30 +02:00
nft_byteorder.c netfilter: nft_byteorder: avoid unneeded le/be conversion steps 2016-01-13 14:02:59 +01:00
nft_cmp.c netfilter: nf_tables: support variable sized data in nft_data_init() 2015-04-13 17:17:30 +02:00
nft_compat.c netfilter: nfnetlink: pass down netns pointer to call() and call_rcu() 2015-12-28 18:41:41 +01:00
nft_counter.c netfilter: nft_counter: fix erroneous return values 2016-02-08 13:05:02 +01:00
nft_ct.c netfilter: nft_ct: keep counters away from CONFIG_NF_CONNTRACK_LABELS 2016-01-14 19:41:16 +01:00
nft_dup_netdev.c netfilter: nf_tables: add packet duplication to the netdev family 2016-01-03 21:04:23 +01:00
nft_dynset.c netfilter: nf_tables: add clone interface to expression operations 2015-11-10 23:47:32 +01:00
nft_exthdr.c netfilter: nf_tables: switch registers to 32 bit addressing 2015-04-13 17:17:29 +02:00
nft_fwd_netdev.c netfilter: nf_tables: add forward expression to the netdev family 2016-01-04 17:48:38 +01:00
nft_hash.c netfilter: nf_tables: variable sized set element keys / data 2015-04-13 17:17:31 +02:00
nft_immediate.c netfilter: nf_tables: support variable sized data in nft_data_init() 2015-04-13 17:17:30 +02:00
nft_limit.c netfilter: nft_limit: allow to invert matching criteria 2016-01-03 20:58:52 +01:00
nft_log.c netfilter: nf_tables: Use pkt->net instead of computing net from the passed net_devices 2015-09-18 21:58:49 +02:00
nft_lookup.c netfilter: nf_tables: add flag to indicate set contains expressions 2015-04-13 20:12:32 +02:00
nft_masq.c netfilter: nf_tables: validate hooks in NAT expressions 2015-01-19 14:52:39 +01:00
nft_meta.c netfilter: meta: add support for setting skb->pkttype 2015-12-18 14:12:56 +01:00
nft_nat.c netfilter: nf_tables: switch registers to 32 bit addressing 2015-04-13 17:17:29 +02:00
nft_payload.c netfilter: nft_payload: add packet mangling support 2015-11-25 13:54:51 +01:00
nft_queue.c netfilter: nf_tables: kill nft_pktinfo.ops 2015-09-18 21:58:01 +02:00
nft_rbtree.c netfilter: nf_tables: variable sized set element keys / data 2015-04-13 17:17:31 +02:00
nft_redir.c netfilter: nf_tables: add register parsing/dumping helpers 2015-04-13 17:17:28 +02:00
nft_reject_inet.c ipv4: Push struct net down into nf_send_reset 2015-09-29 20:21:31 +02:00
nft_reject.c netfilter; Add some missing default cases to switch statements in nft_reject. 2015-04-27 13:20:34 -04:00
x_tables.c netfilter: Set /proc/net entries owner to root in namespace 2015-11-25 13:54:09 +01:00
xt_addrtype.c netfilter: x_tables: Use par->net instead of computing from the passed net devices 2015-09-18 21:58:25 +02:00
xt_AUDIT.c netfilter: Convert uses of __constant_<foo> to <foo> 2014-03-13 14:13:19 +01:00
xt_bpf.c net: filter: split 'struct sk_filter' into socket and bpf parts 2014-08-02 15:03:58 -07:00
xt_cgroup.c netfilter: implement xt_cgroup cgroup2 path match 2015-12-14 20:34:55 +01:00
xt_CHECKSUM.c
xt_CLASSIFY.c
xt_cluster.c net: use reciprocal_scale() helper 2014-08-23 12:21:21 -07:00
xt_comment.c
xt_connbytes.c netfilter: Convert pr_warning to pr_warn 2014-09-10 12:40:10 -07:00
xt_connlabel.c netfilter: connlabels: Export setting connlabel length 2015-08-27 11:40:43 -07:00
xt_connlimit.c netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple 2015-09-18 22:00:04 +02:00
xt_connmark.c netfilter: Fix FSF address in file headers 2013-12-06 12:37:57 -05:00
xt_CONNSECMARK.c
xt_conntrack.c
xt_cpu.c
xt_CT.c netfilter: cttimeout: add netns support 2015-12-14 12:48:58 +01:00
xt_dccp.c
xt_devgroup.c
xt_dscp.c
xt_DSCP.c netfilter: fix various sparse warnings 2014-11-13 12:14:42 +01:00
xt_ecn.c
xt_esp.c
xt_hashlimit.c netfilter: Remove checks of seq_printf() return values 2014-11-05 14:11:02 -05:00
xt_helper.c
xt_hl.c
xt_HL.c
xt_HMARK.c net: use reciprocal_scale() helper 2014-08-23 12:21:21 -07:00
xt_IDLETIMER.c netfilter: IDLETIMER: fix lockdep warning 2015-07-13 17:23:25 +02:00
xt_ipcomp.c netfilter: xt_ipcomp: Use ntohs to ease sparse warning 2014-02-19 11:41:25 +01:00
xt_iprange.c
xt_ipvs.c ipvs: Pass ipvs into conn_out_get 2015-09-24 09:34:41 +09:00
xt_l2tp.c netfilter: introduce l2tp match extension 2014-01-09 21:36:39 +01:00
xt_LED.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-08-05 18:46:26 -07:00
xt_length.c
xt_limit.c
xt_LOG.c netfilter: x_tables: Use par->net instead of computing from the passed net devices 2015-09-18 21:58:25 +02:00
xt_mac.c
xt_mark.c netfilter: xt_MARK: Add ARP support 2015-05-14 13:00:27 +02:00
xt_multiport.c
xt_nat.c
xt_NETMAP.c
xt_nfacct.c netfilter: nfacct: per network namespace support 2015-08-07 11:50:56 +02:00
xt_NFLOG.c netfilter: x_tables: Use par->net instead of computing from the passed net devices 2015-09-18 21:58:25 +02:00
xt_NFQUEUE.c netfilter: xt_NFQUEUE: separate reusable code 2013-12-07 23:20:45 +01:00
xt_osf.c netfilter: nfnetlink: pass down netns pointer to call() and call_rcu() 2015-12-28 18:41:41 +01:00
xt_owner.c netfilter: xt_owner: use skb_to_full_sk() helper 2015-11-08 20:56:39 -05:00
xt_physdev.c netfilter: physdev: use helpers 2015-04-08 16:49:09 +02:00
xt_pkttype.c
xt_policy.c
xt_quota.c
xt_rateest.c
xt_RATEEST.c net: sched: make bstats per cpu and estimator RCU safe 2014-09-30 01:02:26 -04:00
xt_realm.c
xt_recent.c netfilter: x_tables: Use par->net instead of computing from the passed net devices 2015-09-18 21:58:25 +02:00
xt_REDIRECT.c netfilter: combine IPv4 and IPv6 nf_nat_redirect code in one module 2014-11-27 13:08:42 +01:00
xt_repldata.h net: netfilter: LLVMLinux: vlais-netfilter 2014-06-07 11:44:39 -07:00
xt_sctp.c
xt_SECMARK.c
xt_set.c netfilter: ipset: Fix coding styles reported by checkpatch.pl 2015-06-14 10:40:18 +02:00
xt_socket.c netfilter: x_tables: Use par->net instead of computing from the passed net devices 2015-09-18 21:58:25 +02:00
xt_state.c
xt_statistic.c net: replace macros net_random and net_srandom with direct calls to prandom 2014-01-14 15:15:25 -08:00
xt_string.c net: Remove state argument from skb_find_text() 2015-02-22 15:59:54 -05:00
xt_tcpmss.c
xt_TCPMSS.c netfilter: xt_TCPMSS: handle CHECKSUM_COMPLETE in tcpmss_tg6() 2016-01-18 12:18:17 +01:00
xt_TCPOPTSTRIP.c net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool 2015-08-17 21:33:06 -07:00
xt_tcpudp.c
xt_TEE.c netfilter: tee: select NF_DUP_IPV6 unconditionally 2016-02-08 12:58:28 +01:00
xt_time.c
xt_TPROXY.c netfilter: x_tables: Use par->net instead of computing from the passed net devices 2015-09-18 21:58:25 +02:00
xt_TRACE.c
xt_u32.c