linux/net/openvswitch
Joe Stringer 49e261a8a2 openvswitch: Orphan skbs before IPv6 defrag
This is the IPv6 counterpart to commit 8282f27449 ("inet: frag: Always
orphan skbs inside ip_defrag()").

Prior to commit 029f7f3b87 ("netfilter: ipv6: nf_defrag: avoid/free
clone operations"), ipv6 fragments sent to nf_ct_frag6_gather() would be
cloned (implicitly orphaning) prior to queueing for reassembly. As such,
when the IPv6 message is eventually reassembled, the skb->sk for all
fragments would be NULL. After that commit was introduced, rather than
cloning, the original skbs were queued directly without orphaning. The
end result is that all frags except for the first and last may have a
socket attached.

This commit explicitly orphans such skbs during nf_ct_frag6_gather() to
prevent BUG_ON(skb->sk) during a later call to ip6_fragment().

kernel BUG at net/ipv6/ip6_output.c:631!
[...]
Call Trace:
 <IRQ>
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffffa042c7c0>] ? do_output.isra.28+0x1b0/0x1b0 [openvswitch]
 [<ffffffff810bb8a2>] ? __lock_is_held+0x52/0x70
 [<ffffffffa042c587>] ovs_fragment+0x1f7/0x280 [openvswitch]
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff817be416>] ? _raw_spin_unlock_irqrestore+0x36/0x50
 [<ffffffff81697ea0>] ? dst_discard_out+0x20/0x20
 [<ffffffff81697e80>] ? dst_ifdown+0x80/0x80
 [<ffffffffa042c703>] do_output.isra.28+0xf3/0x1b0 [openvswitch]
 [<ffffffffa042d279>] do_execute_actions+0x709/0x12c0 [openvswitch]
 [<ffffffffa04340a4>] ? ovs_flow_stats_update+0x74/0x1e0 [openvswitch]
 [<ffffffffa04340d1>] ? ovs_flow_stats_update+0xa1/0x1e0 [openvswitch]
 [<ffffffff817be387>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffffa042de75>] ovs_execute_actions+0x45/0x120 [openvswitch]
 [<ffffffffa0432d65>] ovs_dp_process_packet+0x85/0x150 [openvswitch]
 [<ffffffff817be387>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffffa042def4>] ovs_execute_actions+0xc4/0x120 [openvswitch]
 [<ffffffffa0432d65>] ovs_dp_process_packet+0x85/0x150 [openvswitch]
 [<ffffffffa04337f2>] ? key_extract+0x442/0xc10 [openvswitch]
 [<ffffffffa043b26d>] ovs_vport_receive+0x5d/0xb0 [openvswitch]
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffff817be416>] ? _raw_spin_unlock_irqrestore+0x36/0x50
 [<ffffffffa043c11d>] internal_dev_xmit+0x6d/0x150 [openvswitch]
 [<ffffffffa043c0b5>] ? internal_dev_xmit+0x5/0x150 [openvswitch]
 [<ffffffff8168fb5f>] dev_hard_start_xmit+0x2df/0x660
 [<ffffffff8168f5ea>] ? validate_xmit_skb.isra.105.part.106+0x1a/0x2b0
 [<ffffffff81690925>] __dev_queue_xmit+0x8f5/0x950
 [<ffffffff81690080>] ? __dev_queue_xmit+0x50/0x950
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff81690990>] dev_queue_xmit+0x10/0x20
 [<ffffffff8169a418>] neigh_resolve_output+0x178/0x220
 [<ffffffff81752759>] ? ip6_finish_output2+0x219/0x7b0
 [<ffffffff81752759>] ip6_finish_output2+0x219/0x7b0
 [<ffffffff817525a5>] ? ip6_finish_output2+0x65/0x7b0
 [<ffffffff816cde2b>] ? ip_idents_reserve+0x6b/0x80
 [<ffffffff8175488f>] ? ip6_fragment+0x93f/0xc50
 [<ffffffff81754af1>] ip6_fragment+0xba1/0xc50
 [<ffffffff81752540>] ? ip6_flush_pending_frames+0x40/0x40
 [<ffffffff81754c6b>] ip6_finish_output+0xcb/0x1d0
 [<ffffffff81754dcf>] ip6_output+0x5f/0x1a0
 [<ffffffff81754ba0>] ? ip6_fragment+0xc50/0xc50
 [<ffffffff81797fbd>] ip6_local_out+0x3d/0x80
 [<ffffffff817554df>] ip6_send_skb+0x2f/0xc0
 [<ffffffff817555bd>] ip6_push_pending_frames+0x4d/0x50
 [<ffffffff817796cc>] icmpv6_push_pending_frames+0xac/0xe0
 [<ffffffff8177a4be>] icmpv6_echo_reply+0x42e/0x500
 [<ffffffff8177acbf>] icmpv6_rcv+0x4cf/0x580
 [<ffffffff81755ac7>] ip6_input_finish+0x1a7/0x690
 [<ffffffff81755925>] ? ip6_input_finish+0x5/0x690
 [<ffffffff817567a0>] ip6_input+0x30/0xa0
 [<ffffffff81755920>] ? ip6_rcv_finish+0x1a0/0x1a0
 [<ffffffff817557ce>] ip6_rcv_finish+0x4e/0x1a0
 [<ffffffff8175640f>] ipv6_rcv+0x45f/0x7c0
 [<ffffffff81755fe6>] ? ipv6_rcv+0x36/0x7c0
 [<ffffffff81755780>] ? ip6_make_skb+0x1c0/0x1c0
 [<ffffffff8168b649>] __netif_receive_skb_core+0x229/0xb80
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff8168c07f>] ? process_backlog+0x6f/0x230
 [<ffffffff8168bfb6>] __netif_receive_skb+0x16/0x70
 [<ffffffff8168c088>] process_backlog+0x78/0x230
 [<ffffffff8168c0ed>] ? process_backlog+0xdd/0x230
 [<ffffffff8168db43>] net_rx_action+0x203/0x480
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff817c156e>] __do_softirq+0xde/0x49f
 [<ffffffff81752768>] ? ip6_finish_output2+0x228/0x7b0
 [<ffffffff817c070c>] do_softirq_own_stack+0x1c/0x30
 <EOI>
 [<ffffffff8106f88b>] do_softirq.part.18+0x3b/0x40
 [<ffffffff8106f946>] __local_bh_enable_ip+0xb6/0xc0
 [<ffffffff81752791>] ip6_finish_output2+0x251/0x7b0
 [<ffffffff81754af1>] ? ip6_fragment+0xba1/0xc50
 [<ffffffff816cde2b>] ? ip_idents_reserve+0x6b/0x80
 [<ffffffff8175488f>] ? ip6_fragment+0x93f/0xc50
 [<ffffffff81754af1>] ip6_fragment+0xba1/0xc50
 [<ffffffff81752540>] ? ip6_flush_pending_frames+0x40/0x40
 [<ffffffff81754c6b>] ip6_finish_output+0xcb/0x1d0
 [<ffffffff81754dcf>] ip6_output+0x5f/0x1a0
 [<ffffffff81754ba0>] ? ip6_fragment+0xc50/0xc50
 [<ffffffff81797fbd>] ip6_local_out+0x3d/0x80
 [<ffffffff817554df>] ip6_send_skb+0x2f/0xc0
 [<ffffffff817555bd>] ip6_push_pending_frames+0x4d/0x50
 [<ffffffff81778558>] rawv6_sendmsg+0xa28/0xe30
 [<ffffffff81719097>] ? inet_sendmsg+0xc7/0x1d0
 [<ffffffff817190d6>] inet_sendmsg+0x106/0x1d0
 [<ffffffff81718fd5>] ? inet_sendmsg+0x5/0x1d0
 [<ffffffff8166d078>] sock_sendmsg+0x38/0x50
 [<ffffffff8166d4d6>] SYSC_sendto+0xf6/0x170
 [<ffffffff8100201b>] ? trace_hardirqs_on_thunk+0x1b/0x1d
 [<ffffffff8166e38e>] SyS_sendto+0xe/0x10
 [<ffffffff817bebe5>] entry_SYSCALL_64_fastpath+0x18/0xa8
Code: 06 48 83 3f 00 75 26 48 8b 87 d8 00 00 00 2b 87 d0 00 00 00 48 39 d0 72 14 8b 87 e4 00 00 00 83 f8 01 75 09 48 83 7f 18 00 74 9a <0f> 0b 41 8b 86 cc 00 00 00 49 8#
RIP  [<ffffffff8175468a>] ip6_fragment+0x73a/0xc50
 RSP <ffff880072803120>

Fixes: 029f7f3b87 ("netfilter: ipv6: nf_defrag: avoid/free clone
operations")
Reported-by: Daniele Di Proietto <diproiettod@vmware.com>
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-21 13:42:05 -04:00
..
actions.c net: use skb_postpush_rcsum instead of own implementations 2016-02-19 23:43:10 -05:00
conntrack.c openvswitch: Orphan skbs before IPv6 defrag 2016-04-21 13:42:05 -04:00
conntrack.h openvswitch: Interface with NAT. 2016-03-14 23:47:29 +01:00
datapath.c ovs: allow nl 'flow set' to use ufid without flow key 2016-03-13 22:18:26 -04:00
datapath.h ovs: propagate per dp max headroom to all vports 2016-03-01 15:54:30 -05:00
dp_notify.c openvswitch: fix hangup on vxlan/gre/geneve device deletion 2015-12-03 14:29:25 -05:00
flow_netlink.c openvswitch: allow output of MPLS packets on tunnel vports 2016-03-18 18:26:38 -04:00
flow_netlink.h openvswitch: Fix egress tunnel info. 2015-10-22 19:39:25 -07:00
flow_table.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-20 06:08:27 -07:00
flow_table.h openvswitch: Zero flows on allocation. 2015-09-22 17:33:41 -07:00
flow.c openvswitch: add tunnel protocol to sw_flow_key 2015-10-07 04:17:59 -07:00
flow.h ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it 2016-03-18 19:38:46 -04:00
Kconfig openvswitch: call only into reachable nf-nat code 2016-03-28 17:58:59 +02:00
Makefile openvswitch: Remove conntrack Kconfig option. 2015-09-06 23:48:33 -07:00
vport-geneve.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2016-03-17 21:38:27 -07:00
vport-gre.c openvswitch: properly refcount vport-vxlan module 2015-12-02 11:50:59 -05:00
vport-internal_dev.c ovs: internal_set_rx_headroom() can be static 2016-03-18 17:50:36 -04:00
vport-internal_dev.h
vport-netdev.c net: use skb_postpush_rcsum instead of own implementations 2016-02-19 23:43:10 -05:00
vport-netdev.h openvswitch: Use dev_queue_xmit for vport send. 2015-10-22 06:46:16 -07:00
vport-vxlan.c lwt: fix rx checksum setting for lwt devices tunneling over ipv6 2016-02-19 15:39:30 -05:00
vport.c openvswitch: properly refcount vport-vxlan module 2015-12-02 11:50:59 -05:00
vport.h net: use skb_postpush_rcsum instead of own implementations 2016-02-19 23:43:10 -05:00