linux/net/ipv6/ip6_input.c, branch v5.4

ipv6: drop incoming packets having a v4mapped source address

2019-10-03T15:40:21Z

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 Cc: Florian Westphal Cc: Hannes Frederic Sowa Reported-by: syzbot Signed-off-by: David S. Miller

netfilter: drop bridge nf reset from nf_reset

2019-10-01T16:42:15Z

commit 174e23810cd31 ("sk_buff: drop all skb extensions on free and skb scrubbing") made napi recycle always drop skb extensions. The additional skb_ext_del() that is performed via nf_reset on napi skb recycle is not needed anymore. Most nf_reset() calls in the stack are there so queued skb won't block 'rmmod nf_conntrack' indefinitely. This removes the skb_ext_del from nf_reset, and renames it to a more fitting nf_reset_ct(). In a few selected places, add a call to skb_ext_reset to make sure that no active extensions remain. I am submitting this for "net", because we're still early in the release cycle. The patch applies to net-next too, but I think the rename causes needless divergence between those trees. Suggested-by: Eric Dumazet Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

net: ipv6: fix listify ip6_rcv_finish in case of forwarding

2019-08-23T21:42:14Z

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 Acked-by: Edward Cree Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: use indirect calls helpers at early demux stage

2019-05-05T17:38:04Z

So that we avoid another indirect call per RX packet, if early demux is enabled. Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

net: use indirect calls helpers for L3 handler hooks

2019-05-05T17:38:04Z

So that we avoid another indirect call per RX packet in the common case. Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2018-12-10T05:43:31Z

Several conflicts, seemingly all over the place. I used Stephen Rothwell's sample resolutions for many of these, if not just to double check my own work, so definitely the credit largely goes to him. The NFP conflict consisted of a bug fix (moving operations past the rhashtable operation) while chaning the initial argument in the function call in the moved code. The net/dsa/master.c conflict had to do with a bug fix intermixing of making dsa_master_set_mtu() static with the fixing of the tagging attribute location. cls_flower had a conflict because the dup reject fix from Or overlapped with the addition of port range classifiction. __set_phy_supported()'s conflict was relatively easy to resolve because Andrew fixed it in both trees, so it was just a matter of taking the net-next copy. Or at least I think it was :-) Joe Stringer's fix to the handling of netns id 0 in bpf_sk_lookup() intermixed with changes on how the sdif and caller_net are calculated in these code paths in net-next. The remaining BPF conflicts were largely about the addition of the __bpf_md_ptr stuff in 'net' overlapping with adjustments and additions to the relevant data structure where the MD pointer macros are used. Signed-off-by: David S. Miller

net: use skb_list_del_init() to remove from RX sublists

2018-12-06T00:22:05Z

list_del() leaves the skb->next pointer poisoned, which can then lead to a crash in e.g. OVS forwarding. For example, setting up an OVS VXLAN forwarding bridge on sfc as per: ======== $ ovs-vsctl show 5dfd9c47-f04b-4aaa-aa96-4fbb0a522a30 Bridge "br0" Port "br0" Interface "br0" type: internal Port "enp6s0f0" Interface "enp6s0f0" Port "vxlan0" Interface "vxlan0" type: vxlan options: {key="1", local_ip="10.0.0.5", remote_ip="10.0.0.4"} ovs_version: "2.5.0" ======== (where 10.0.0.5 is an address on enp6s0f1) and sending traffic across it will lead to the following panic: ======== general protection fault: 0000 [#1] SMP PTI CPU: 5 PID: 0 Comm: swapper/5 Not tainted 4.20.0-rc3-ehc+ #701 Hardware name: Dell Inc. PowerEdge R710/0M233H, BIOS 6.4.0 07/23/2013 RIP: 0010:dev_hard_start_xmit+0x38/0x200 Code: 53 48 89 fb 48 83 ec 20 48 85 ff 48 89 54 24 08 48 89 4c 24 18 0f 84 ab 01 00 00 48 8d 86 90 00 00 00 48 89 f5 48 89 44 24 10 <4c> 8b 33 48 c7 03 00 00 00 00 48 8b 05 c7 d1 b3 00 4d 85 f6 0f 95 RSP: 0018:ffff888627b437e0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: dead000000000100 RCX: ffff88862279c000 RDX: ffff888614a342c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888618a88000 R08: 0000000000000001 R09: 00000000000003e8 R10: 0000000000000000 R11: ffff888614a34140 R12: 0000000000000000 R13: 0000000000000062 R14: dead000000000100 R15: ffff888616430000 FS: 0000000000000000(0000) GS:ffff888627b40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6d2bc6d000 CR3: 000000000200a000 CR4: 00000000000006e0 Call Trace: __dev_queue_xmit+0x623/0x870 ? masked_flow_lookup+0xf7/0x220 [openvswitch] ? ep_poll_callback+0x101/0x310 do_execute_actions+0xaba/0xaf0 [openvswitch] ? __wake_up_common+0x8a/0x150 ? __wake_up_common_lock+0x87/0xc0 ? queue_userspace_packet+0x31c/0x5b0 [openvswitch] ovs_execute_actions+0x47/0x120 [openvswitch] ovs_dp_process_packet+0x7d/0x110 [openvswitch] ovs_vport_receive+0x6e/0xd0 [openvswitch] ? dst_alloc+0x64/0x90 ? rt_dst_alloc+0x50/0xd0 ? ip_route_input_slow+0x19a/0x9a0 ? __udp_enqueue_schedule_skb+0x198/0x1b0 ? __udp4_lib_rcv+0x856/0xa30 ? __udp4_lib_rcv+0x856/0xa30 ? cpumask_next_and+0x19/0x20 ? find_busiest_group+0x12d/0xcd0 netdev_frame_hook+0xce/0x150 [openvswitch] __netif_receive_skb_core+0x205/0xae0 __netif_receive_skb_list_core+0x11e/0x220 netif_receive_skb_list+0x203/0x460 ? __efx_rx_packet+0x335/0x5e0 [sfc] efx_poll+0x182/0x320 [sfc] net_rx_action+0x294/0x3c0 __do_softirq+0xca/0x297 irq_exit+0xa6/0xb0 do_IRQ+0x54/0xd0 common_interrupt+0xf/0xf ======== So, in all listified-receive handling, instead pull skbs off the lists with skb_list_del_init(). Fixes: 9af86f933894 ("net: core: fix use-after-free in __netif_receive_skb_list_core") Fixes: 7da517a3bc52 ("net: core: Another step of skb receive list processing") Fixes: a4ca8b7df73c ("net: ipv4: fix drop handling in ip_list_rcv() and ip_list_rcv_finish()") Fixes: d8269e2cbf90 ("net: ipv6: listify ipv6_rcv() and ip6_rcv_finish()") Signed-off-by: Edward Cree Signed-off-by: David S. Miller

ipv6: factor out protocol delivery helper

2018-11-08T00:23:05Z

So that we can re-use it at the UDP level in the next patch rfc v3 -> v1: - add the helper declaration into the ipv6 header Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller

ipv6: handling of multicast packets received in VRF

2018-11-08T00:12:39Z

If the skb for multicast packets marked as enslaved to a VRF are received, then the secondary device index should be used to obtain the real device. And verify the multicast address against the enslaved rather than the l3mdev device. Signed-off-by: Dewi Morgan Signed-off-by: Mike Manning Reviewed-by: David Ahern Tested-by: David Ahern Signed-off-by: David S. Miller