From: Joe Stringer Date: Mon, 18 Apr 2016 21:51:47 +0000 (-0700) Subject: openvswitch: Orphan skbs before IPv6 defrag X-Git-Tag: v5.15~13795^2~11 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=49e261a8a21e0960a3f7ff187a453ba1c1149053;p=platform%2Fkernel%2Flinux-starfive.git openvswitch: Orphan skbs before IPv6 defrag This is the IPv6 counterpart to commit 8282f27449bf ("inet: frag: Always orphan skbs inside ip_defrag()"). Prior to commit 029f7f3b8701 ("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: [] ? __lock_acquire+0x927/0x20a0 [] ? do_output.isra.28+0x1b0/0x1b0 [openvswitch] [] ? __lock_is_held+0x52/0x70 [] ovs_fragment+0x1f7/0x280 [openvswitch] [] ? mark_held_locks+0x75/0xa0 [] ? _raw_spin_unlock_irqrestore+0x36/0x50 [] ? dst_discard_out+0x20/0x20 [] ? dst_ifdown+0x80/0x80 [] do_output.isra.28+0xf3/0x1b0 [openvswitch] [] do_execute_actions+0x709/0x12c0 [openvswitch] [] ? ovs_flow_stats_update+0x74/0x1e0 [openvswitch] [] ? ovs_flow_stats_update+0xa1/0x1e0 [openvswitch] [] ? _raw_spin_unlock+0x27/0x40 [] ovs_execute_actions+0x45/0x120 [openvswitch] [] ovs_dp_process_packet+0x85/0x150 [openvswitch] [] ? _raw_spin_unlock+0x27/0x40 [] ovs_execute_actions+0xc4/0x120 [openvswitch] [] ovs_dp_process_packet+0x85/0x150 [openvswitch] [] ? key_extract+0x442/0xc10 [openvswitch] [] ovs_vport_receive+0x5d/0xb0 [openvswitch] [] ? __lock_acquire+0x927/0x20a0 [] ? __lock_acquire+0x927/0x20a0 [] ? __lock_acquire+0x927/0x20a0 [] ? _raw_spin_unlock_irqrestore+0x36/0x50 [] internal_dev_xmit+0x6d/0x150 [openvswitch] [] ? internal_dev_xmit+0x5/0x150 [openvswitch] [] dev_hard_start_xmit+0x2df/0x660 [] ? validate_xmit_skb.isra.105.part.106+0x1a/0x2b0 [] __dev_queue_xmit+0x8f5/0x950 [] ? __dev_queue_xmit+0x50/0x950 [] ? mark_held_locks+0x75/0xa0 [] dev_queue_xmit+0x10/0x20 [] neigh_resolve_output+0x178/0x220 [] ? ip6_finish_output2+0x219/0x7b0 [] ip6_finish_output2+0x219/0x7b0 [] ? ip6_finish_output2+0x65/0x7b0 [] ? ip_idents_reserve+0x6b/0x80 [] ? ip6_fragment+0x93f/0xc50 [] ip6_fragment+0xba1/0xc50 [] ? ip6_flush_pending_frames+0x40/0x40 [] ip6_finish_output+0xcb/0x1d0 [] ip6_output+0x5f/0x1a0 [] ? ip6_fragment+0xc50/0xc50 [] ip6_local_out+0x3d/0x80 [] ip6_send_skb+0x2f/0xc0 [] ip6_push_pending_frames+0x4d/0x50 [] icmpv6_push_pending_frames+0xac/0xe0 [] icmpv6_echo_reply+0x42e/0x500 [] icmpv6_rcv+0x4cf/0x580 [] ip6_input_finish+0x1a7/0x690 [] ? ip6_input_finish+0x5/0x690 [] ip6_input+0x30/0xa0 [] ? ip6_rcv_finish+0x1a0/0x1a0 [] ip6_rcv_finish+0x4e/0x1a0 [] ipv6_rcv+0x45f/0x7c0 [] ? ipv6_rcv+0x36/0x7c0 [] ? ip6_make_skb+0x1c0/0x1c0 [] __netif_receive_skb_core+0x229/0xb80 [] ? mark_held_locks+0x75/0xa0 [] ? process_backlog+0x6f/0x230 [] __netif_receive_skb+0x16/0x70 [] process_backlog+0x78/0x230 [] ? process_backlog+0xdd/0x230 [] net_rx_action+0x203/0x480 [] ? mark_held_locks+0x75/0xa0 [] __do_softirq+0xde/0x49f [] ? ip6_finish_output2+0x228/0x7b0 [] do_softirq_own_stack+0x1c/0x30 [] do_softirq.part.18+0x3b/0x40 [] __local_bh_enable_ip+0xb6/0xc0 [] ip6_finish_output2+0x251/0x7b0 [] ? ip6_fragment+0xba1/0xc50 [] ? ip_idents_reserve+0x6b/0x80 [] ? ip6_fragment+0x93f/0xc50 [] ip6_fragment+0xba1/0xc50 [] ? ip6_flush_pending_frames+0x40/0x40 [] ip6_finish_output+0xcb/0x1d0 [] ip6_output+0x5f/0x1a0 [] ? ip6_fragment+0xc50/0xc50 [] ip6_local_out+0x3d/0x80 [] ip6_send_skb+0x2f/0xc0 [] ip6_push_pending_frames+0x4d/0x50 [] rawv6_sendmsg+0xa28/0xe30 [] ? inet_sendmsg+0xc7/0x1d0 [] inet_sendmsg+0x106/0x1d0 [] ? inet_sendmsg+0x5/0x1d0 [] sock_sendmsg+0x38/0x50 [] SYSC_sendto+0xf6/0x170 [] ? trace_hardirqs_on_thunk+0x1b/0x1d [] SyS_sendto+0xe/0x10 [] 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 [] ip6_fragment+0x73a/0xc50 RSP Fixes: 029f7f3b8701 ("netfilter: ipv6: nf_defrag: avoid/free clone operations") Reported-by: Daniele Di Proietto Signed-off-by: Joe Stringer Signed-off-by: David S. Miller --- diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index 1b9d286..b5fea110 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -367,6 +367,7 @@ static int handle_fragments(struct net *net, struct sw_flow_key *key, } else if (key->eth.type == htons(ETH_P_IPV6)) { enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; + skb_orphan(skb); memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); err = nf_ct_frag6_gather(net, skb, user); if (err)