Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 syzkaller login: [ 34.318313] IPVS: Creating netns size=2712 id=1 [ 34.323125] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.0.206' (ECDSA) to the list of known hosts. 2020/09/30 11:24:38 parsed 1 programs 2020/09/30 11:24:38 executed programs: 0 [ 41.645016] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 41.664325] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 41.685241] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 41.705283] IPVS: Creating netns size=2712 id=2 [ 41.710120] IPVS: ftp: loaded support on port[0] = 21 [ 41.723705] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 41.731981] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 41.746112] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 41.811358] IPVS: Creating netns size=2712 id=3 [ 41.816172] IPVS: ftp: loaded support on port[0] = 21 [ 41.960163] chnl_net:caif_netlink_parms(): no params data found [ 41.974340] IPVS: Creating netns size=2712 id=4 [ 41.979606] IPVS: ftp: loaded support on port[0] = 21 [ 42.163087] chnl_net:caif_netlink_parms(): no params data found [ 42.222623] IPVS: Creating netns size=2712 id=5 [ 42.227445] IPVS: ftp: loaded support on port[0] = 21 [ 42.315025] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.321954] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.331206] device bridge_slave_0 entered promiscuous mode [ 42.372220] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.378715] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.387301] device bridge_slave_1 entered promiscuous mode [ 42.516341] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.530071] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.585254] IPVS: Creating netns size=2712 id=6 [ 42.591348] IPVS: ftp: loaded support on port[0] = 21 [ 42.675378] chnl_net:caif_netlink_parms(): no params data found [ 42.729730] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.736111] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.745721] device bridge_slave_0 entered promiscuous mode [ 42.781971] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.789107] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.797577] device bridge_slave_1 entered promiscuous mode [ 42.823687] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 42.863566] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 42.889401] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.897725] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.944332] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.952982] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 43.004991] IPVS: Creating netns size=2712 id=7 [ 43.010474] IPVS: ftp: loaded support on port[0] = 21 [ 43.209496] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.254856] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 43.317515] bridge0: port 1(bridge_slave_0) entered blocking state [ 43.324077] bridge0: port 1(bridge_slave_0) entered disabled state [ 43.333278] device bridge_slave_0 entered promiscuous mode [ 43.360848] chnl_net:caif_netlink_parms(): no params data found [ 43.438989] bridge0: port 2(bridge_slave_1) entered blocking state [ 43.445508] bridge0: port 2(bridge_slave_1) entered disabled state [ 43.454602] device bridge_slave_1 entered promiscuous mode [ 43.471076] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 43.528737] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 43.577469] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 43.635527] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 43.718542] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.725376] chnl_net:caif_netlink_parms(): no params data found [ 43.771620] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 44.076185] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.082768] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.092085] device bridge_slave_0 entered promiscuous mode [ 44.177797] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 44.185353] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 44.205556] bridge0: port 2(bridge_slave_1) entered blocking state [ 44.213145] bridge0: port 2(bridge_slave_1) entered disabled state [ 44.222545] device bridge_slave_1 entered promiscuous mode [ 44.314772] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 44.369452] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 44.425711] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 44.492513] chnl_net:caif_netlink_parms(): no params data found [ 44.506897] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 44.554420] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.561315] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.570719] device bridge_slave_0 entered promiscuous mode [ 44.578752] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 44.603387] bridge0: port 2(bridge_slave_1) entered blocking state [ 44.609829] bridge0: port 2(bridge_slave_1) entered disabled state [ 44.619546] device bridge_slave_1 entered promiscuous mode [ 44.787019] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 44.834497] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 44.875596] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 44.924709] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 44.932665] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 45.158940] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 45.175291] ------------[ cut here ]------------ [ 45.180415] WARNING: CPU: 1 PID: 5912 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 45.189175] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 45.196171] Kernel panic - not syncing: panic_on_warn set ... [ 45.196171] [ 45.203502] CPU: 1 PID: 5912 Comm: syz-executor.1 Not tainted 4.6.0-syzkaller #0 [ 45.211054] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.220384] 0000000000000000 ffff8800b597efc8 ffffffff82e18b12 ffffffff85e81040 [ 45.228384] ffff8800b597f0a0 ffffffff85f2bc00 ffffffff8191bd7b 0000000000000009 [ 45.236359] ffff8800b597f090 ffffffff8160d884 0000000041b58ab3 ffffffff86b4158a [ 45.244346] Call Trace: [ 45.246903] [] dump_stack+0x136/0x1d4 [ 45.252324] [] ? sysfs_warn_dup+0x7b/0xa0 [ 45.258107] [] panic+0x1af/0x348 [ 45.263093] [] ? to_vmem_altmap+0x125/0x125 [ 45.269035] [] ? sysfs_warn_dup+0x7b/0xa0 [ 45.274822] [] __warn+0x18d/0x1b0 [ 45.279894] [] warn_slowpath_fmt+0x92/0xb0 [ 45.285746] [] ? __warn+0x1b0/0x1b0 [ 45.291006] [] ? kernfs_path_from_node+0x4a/0x60 [ 45.297382] [] sysfs_warn_dup+0x7b/0xa0 [ 45.302980] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 45.309961] [] sysfs_create_link+0x43/0xb0 [ 45.315827] [] device_add+0x677/0x1350 [ 45.321340] [] ? device_private_init+0x180/0x180 [ 45.327716] [] ? kfree_const+0x1d/0x20 [ 45.333221] [] ? kobject_set_name_vargs+0xb4/0x130 [ 45.339769] [] device_create_groups_vargs+0x1c8/0x220 [ 45.346578] [] device_create+0x88/0xa0 [ 45.352083] [] ? device_create_vargs+0x20/0x20 [ 45.358283] [] ? macvlan_set_mac_address+0x150/0x150 [ 45.365002] [] macvtap_device_event+0x1c4/0x2a0 [ 45.371291] [] notifier_call_chain+0x8b/0x170 [ 45.377417] [] raw_notifier_call_chain+0x11/0x20 [ 45.383888] [] call_netdevice_notifiers_info+0x47/0x80 [ 45.390895] [] register_netdevice+0x8e8/0xd00 [ 45.397010] [] ? netdev_change_features+0x80/0x80 [ 45.403474] [] ? dev_get_nest_level+0x10c/0x1a0 [ 45.409764] [] macvlan_common_newlink+0x8b9/0x1090 [ 45.416316] [] macvtap_newlink+0xbf/0x110 [ 45.422087] [] ? __netlink_ns_capable+0xc7/0xf0 [ 45.428381] [] rtnl_newlink+0xd4b/0x1230 [ 45.434060] [] ? rtnl_link_ops_get+0x5d/0x90 [ 45.440086] [] ? rtnl_newlink+0x319/0x1230 [ 45.445938] [] ? find_next_bit+0x15/0x20 [ 45.451615] [] ? rtnl_setlink+0x2f0/0x2f0 [ 45.457384] [] ? cpuacct_css_alloc+0x160/0x160 [ 45.463601] [] ? update_blocked_averages+0x8f7/0x1540 [ 45.470407] [] ? find_busiest_group+0x2510/0x2510 [ 45.476867] [] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 45.483854] [] ? __netlink_ns_capable+0xc7/0xf0 [ 45.490146] [] rtnetlink_rcv_msg+0x222/0x680 [ 45.496173] [] ? rtnetlink_rcv+0x30/0x30 [ 45.501873] [] ? mutex_lock_nested+0x5fd/0xb30 [ 45.508079] [] ? rtnetlink_rcv+0x16/0x30 [ 45.513759] [] ? netlink_seq_start+0xe0/0xe0 [ 45.519786] [] netlink_rcv_skb+0x242/0x350 [ 45.525638] [] ? rtnetlink_rcv+0x30/0x30 [ 45.531333] [] rtnetlink_rcv+0x25/0x30 [ 45.536837] [] netlink_unicast+0x3da/0x560 [ 45.542706] [] ? netlink_sendskb+0x40/0x40 [ 45.548575] [] netlink_sendmsg+0x9bb/0xb40 [ 45.554425] [] ? nlmsg_notify+0xf0/0xf0 [ 45.560036] [] ? __might_fault+0xf1/0x1b0 [ 45.565802] [] ? security_socket_sendmsg+0x6a/0xa0 [ 45.572349] [] ? nlmsg_notify+0xf0/0xf0 [ 45.577964] [] sock_sendmsg+0xb5/0xf0 [ 45.583384] [] SyS_sendto+0x1ca/0x290 [ 45.588803] [] ? SyS_getpeername+0x240/0x240 [ 45.594846] [] ? kmem_cache_free+0x312/0x430 [ 45.600888] [] ? mntput_no_expire+0xce/0x600 [ 45.606914] [] ? mnt_get_count+0x1c0/0x1c0 [ 45.612782] [] ? mntput+0x52/0x70 [ 45.617856] [] ? task_work_run+0x14a/0x200 [ 45.623724] [] ? trace_hardirqs_off+0xd/0x10 [ 45.629864] [] ? exit_to_usermode_loop+0x112/0x1c0 [ 45.636413] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 45.642965] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 45.650861] Kernel Offset: disabled