Dear NetDevs,
Before I go to bisecting, have you seen a following NULL dereference,
yet? Where should I start looking? It is triggered by deleting netns
(cut-down script attached - triggers every time). This was working
correctly under v4.11.x.
Best Regards,
Michał Mirosław
[1097925.958758] eth0: renamed from tve0x
[1097926.012266] IPv6: ADDRCONF(NETDEV_UP): tve0: link is not ready
[1097926.035396] IPv6: ADDRCONF(NETDEV_CHANGE): tve0: link becomes ready
[1097926.709371] ip6_tables: (C) 2000-2006 Netfilter Core Team
[1097929.961977] BUG: unable to handle kernel NULL pointer dereference at
0000000000000138
[1097929.961983] IP: fib_sync_down_dev+0x19a/0x230
[1097929.961983] PGD 0
[1097929.961984] P4D 0
[1097929.961986] Oops: 0000 [#1] PREEMPT SMP
[1097929.961987] Modules linked in: ip6table_mangle ip6_tables xt_tcpudp
iptable_mangle xt_TPROXY nf_defrag_ipv6 veth nvidia_uvm(PO) cpuid cdc_ether
cdc_subset usbnet mii pci_stub vboxpci(O) vboxnetadp(O) vboxnetflt(O)
vboxdrv(O) tun xt_REDIRECT nf_nat_redirect cdc_acm ipt_MASQUERADE
nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4
nf_nat nf_conntrack bridge stp llc rfcomm snd_emu10k1_synth snd_emux_synth
snd_seq_midi_emul snd_seq_virmidi snd_hrtimer snd_seq_midi snd_seq_midi_event
snd_seq xfrm_user iptable_filter xfrm4_tunnel tunnel4 ipcomp xfrm_ipcomp esp4
ah4 af_key xfrm_algo cpufreq_powersave cpufreq_userspace cpufreq_conservative
nfc fuse bnep binfmt_misc xfs snd_hda_codec_hdmi mxm_wmi btusb btrtl btbcm
btintel bluetooth intel_powerclamp snd_hda_codec_realtek snd_hda_codec_generic
[1097929.962009] kvm_intel snd_hda_intel pl2303 snd_emu10k1 usbserial
input_leds ecdh_generic snd_hda_codec kvm snd_util_mem snd_hda_core
snd_ac97_codec ac97_bus snd_rawmidi snd_seq_device snd_hwdep snd_pcm_oss
snd_mixer_oss snd_pcm snd_timer snd irqbypass sg pcspkr soundcore emu10k1_gp
gameport iTCO_wdt wmi video nvidia_drm(PO) drm_kms_helper syscopyarea
sysfillrect sysimgblt fb_sys_fops drm nvidia_modeset(PO) nvidia(PO) nfsd
auth_rpcgss oid_registry nfs_acl lockd grace sunrpc loop firewire_sbp2
firewire_core crc_itu_t ecryptfs ip_tables x_tables autofs4 algif_skcipher
af_alg sr_mod cdrom raid10 raid0 multipath linear raid456 async_raid6_recov
async_memcpy async_pq uas usb_storage raid6_pq async_xor xor async_tx libcrc32c
crc32c_intel ghash_clmulni_intel i2c_i801 i2c_core xhci_pci xhci_hcd e1000e
[1097929.962034] CPU: 2 PID: 28976 Comm: kworker/u16:2 Tainted: P O
4.12.2mq+ #204
[1097929.962035] Hardware name: System manufacturer System Product Name/P8Z68-V
PRO, BIOS 3603 11/09/2012
[1097929.962037] Workqueue: netns cleanup_net
[1097929.962038] task: ffff8804078ae600 task.stack: ffffc90003b0c000
[1097929.962039] RIP: 0010:fib_sync_down_dev+0x19a/0x230
[1097929.962040] RSP: 0018:ffffc90003b0fc80 EFLAGS: 00010206
[1097929.962041] RAX: 0000000000000011 RBX: ffff880005b70570 RCX:
0000000000000000
[1097929.962042] RDX: 0000000000000000 RSI: 00000000000000ff RDI:
0000000000000000
[1097929.962043] RBP: 0000000000000000 R08: 00000000ffffffff R09:
0000000000000000
[1097929.962044] R10: ffffc90003b0fd10 R11: 0000000000000c79 R12:
ffff880005b70500
[1097929.962044] R13: 0000000000000006 R14: ffff880005b70570 R15:
ffff880405bc5000
[1097929.962045] FS: 0000000000000000(0000) GS:ffff88041ec80000(0000)
knlGS:0000000000000000
[1097929.962046] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1097929.962047] CR2: 0000000000000138 CR3: 0000000001c09000 CR4:
00000000000406e0
[1097929.962047] Call Trace:
[1097929.962050] ? fib_disable_ip+0xc/0x40
[1097929.962051] ? fib_netdev_event+0xe8/0x110
[1097929.962053] ? notifier_call_chain+0x40/0x60
[1097929.962054] ? rollback_registered_many+0x2b6/0x400
[1097929.962056] ? unregister_netdevice_many+0x15/0xa0
[1097929.962057] ? default_device_exit_batch+0x13c/0x170
[1097929.962059] ? do_wait_intr_irq+0x80/0x80
[1097929.962061] ? cleanup_net+0x1d0/0x2c0
[1097929.962062] ? process_one_work+0x1d2/0x3e0
[1097929.962064] ? worker_thread+0x42/0x3d0
[1097929.962065] ? kthread+0xf7/0x130
[1097929.962067] ? trace_event_raw_event_workqueue_work+0xa0/0xa0
[1097929.962068] ? kthread_create_on_node+0x60/0x60
[1097929.962069] ? do_group_exit+0x35/0xa0
[1097929.962070] ? ret_from_fork+0x22/0x30
[1097929.962071] Code: 39 f0 74 77 49 83 fd 04 74 69 49 83 fd 06 74 60 49 83 fd
02 74 5a 49 8b 97 d8 02 00 00 48 89 5c 24 18 48 c7 44 24 10 00 00 00 00 <8b> 92
38 01 00 00 85 d2 74 04 a8 10 75 08 a8 01 0f 84 12 ff ff
[1097929.962085] RIP: fib_sync_down_dev+0x19a/0x230 RSP: ffffc90003b0fc80
[1097929.962086] CR2: 0000000000000138
[1097929.962087] ---[ end trace 07d937abbfe4921d ]---
#!/bin/bash
trap cleanup EXIT
cleanup() {
ip netns del test
ip link del tve0
}
ip netns add test || exit 1
ip link add name tve0 type veth peer name tve0x
ip link set tve0x netns test
ip netns exec test ip link set tve0x name eth0
ip link set tve0 up
ip addr add 10.22.0.1/24 dev tve0
ip route add 10.23.0.0/16 via 10.22.0.2
ip netns exec test ip link set eth0 up
ip netns exec test ip addr add 10.22.0.2/24 dev eth0
ip netns exec test ip route add default via 10.22.0.1 dev eth0
ip netns exec test sysctl net.ipv4.conf.all.forwarding=1
ip netns exec test ip rule add fwmark 1/1 table 1
ip netns exec test ip route add local default dev lo table 1
sleep 1
