[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 syzkaller login: [ 35.872098] IPVS: Creating netns size=2712 id=1 [ 35.877762] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.15.201' (ECDSA) to the list of known hosts. 2020/10/06 17:38:01 parsed 1 programs 2020/10/06 17:38:01 executed programs: 0 [ 43.622500] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 43.666241] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 43.680564] IPVS: Creating netns size=2712 id=2 [ 43.685366] IPVS: ftp: loaded support on port[0] = 21 [ 43.697508] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 43.708359] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 43.727960] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 43.742183] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 43.808940] IPVS: Creating netns size=2712 id=3 [ 43.813964] IPVS: ftp: loaded support on port[0] = 21 [ 43.970081] chnl_net:caif_netlink_parms(): no params data found [ 44.003870] IPVS: Creating netns size=2712 id=4 [ 44.008737] IPVS: ftp: loaded support on port[0] = 21 [ 44.236452] chnl_net:caif_netlink_parms(): no params data found [ 44.250219] IPVS: Creating netns size=2712 id=5 [ 44.258490] IPVS: ftp: loaded support on port[0] = 21 [ 44.464285] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.472297] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.482698] device bridge_slave_0 entered promiscuous mode [ 44.528602] bridge0: port 2(bridge_slave_1) entered blocking state [ 44.535002] bridge0: port 2(bridge_slave_1) entered disabled state [ 44.544832] device bridge_slave_1 entered promiscuous mode [ 44.559247] chnl_net:caif_netlink_parms(): no params data found [ 44.577049] IPVS: Creating netns size=2712 id=6 [ 44.588626] IPVS: ftp: loaded support on port[0] = 21 [ 44.668632] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 44.722661] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 44.873125] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.879826] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.889482] device bridge_slave_0 entered promiscuous mode [ 44.968222] bridge0: port 2(bridge_slave_1) entered blocking state [ 44.974749] bridge0: port 2(bridge_slave_1) entered disabled state [ 44.986142] device bridge_slave_1 entered promiscuous mode [ 45.090242] IPVS: Creating netns size=2712 id=7 [ 45.092349] chnl_net:caif_netlink_parms(): no params data found [ 45.102259] IPVS: ftp: loaded support on port[0] = 21 [ 45.195711] bridge0: port 1(bridge_slave_0) entered blocking state [ 45.202062] bridge0: port 1(bridge_slave_0) entered disabled state [ 45.211674] device bridge_slave_0 entered promiscuous mode [ 45.221984] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 45.230743] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 45.259157] bridge0: port 2(bridge_slave_1) entered blocking state [ 45.265734] bridge0: port 2(bridge_slave_1) entered disabled state [ 45.274444] device bridge_slave_1 entered promiscuous mode [ 45.284261] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 45.292799] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 45.385099] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 45.530013] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 45.547559] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 45.599654] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 45.701550] chnl_net:caif_netlink_parms(): no params data found [ 45.851690] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 45.859718] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 45.876277] bridge0: port 1(bridge_slave_0) entered blocking state [ 45.882758] bridge0: port 1(bridge_slave_0) entered disabled state [ 45.895881] device bridge_slave_0 entered promiscuous mode [ 45.976989] bridge0: port 2(bridge_slave_1) entered blocking state [ 45.983354] bridge0: port 2(bridge_slave_1) entered disabled state [ 45.992897] device bridge_slave_1 entered promiscuous mode [ 46.029551] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 46.137653] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 46.176197] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 46.185517] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 46.295941] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 46.306792] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 46.464572] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 46.548079] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 46.572807] bridge0: port 1(bridge_slave_0) entered blocking state [ 46.579340] bridge0: port 1(bridge_slave_0) entered disabled state [ 46.588888] device bridge_slave_0 entered promiscuous mode [ 46.596897] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 46.635441] chnl_net:caif_netlink_parms(): no params data found [ 46.651299] bridge0: port 2(bridge_slave_1) entered blocking state [ 46.658471] bridge0: port 2(bridge_slave_1) entered disabled state [ 46.667791] device bridge_slave_1 entered promiscuous mode [ 46.675719] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 46.917692] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 46.938440] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 46.977118] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 46.998376] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 47.227903] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 47.347160] ------------[ cut here ]------------ [ 47.351925] WARNING: CPU: 0 PID: 5938 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 47.360398] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 47.367781] Kernel panic - not syncing: panic_on_warn set ... [ 47.367781] [ 47.375119] CPU: 0 PID: 5938 Comm: syz-executor.0 Not tainted 4.6.0-syzkaller #0 [ 47.382619] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.391942] 0000000000000000 ffff8800b1fb6fc8 ffffffff82e18b12 ffffffff85e81040 [ 47.399920] ffff8800b1fb70a0 ffffffff85f2bc00 ffffffff8191bd7b 0000000000000009 [ 47.407883] ffff8800b1fb7090 ffffffff8160d884 0000000041b58ab3 ffffffff86b3fd6a [ 47.415883] Call Trace: [ 47.418440] [] dump_stack+0x136/0x1d4 [ 47.423882] [] ? sysfs_warn_dup+0x7b/0xa0 [ 47.429695] [] panic+0x1af/0x348 [ 47.434678] [] ? to_vmem_altmap+0x125/0x125 [ 47.440618] [] ? sysfs_warn_dup+0x7b/0xa0 [ 47.446385] [] __warn+0x18d/0x1b0 [ 47.451456] [] warn_slowpath_fmt+0x92/0xb0 [ 47.457307] [] ? __warn+0x1b0/0x1b0 [ 47.462591] [] ? kernfs_path_from_node+0x4a/0x60 [ 47.468987] [] sysfs_warn_dup+0x7b/0xa0 [ 47.474617] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 47.481696] [] sysfs_create_link+0x43/0xb0 [ 47.487587] [] device_add+0x677/0x1350 [ 47.493093] [] ? device_private_init+0x180/0x180 [ 47.499465] [] ? kfree_const+0x1d/0x20 [ 47.504971] [] ? kobject_set_name_vargs+0xb4/0x130 [ 47.511526] [] device_create_groups_vargs+0x1c8/0x220 [ 47.518333] [] device_create+0x88/0xa0 [ 47.523842] [] ? device_create_vargs+0x20/0x20 [ 47.530047] [] ? macvlan_set_mac_address+0x150/0x150 [ 47.536767] [] macvtap_device_event+0x1c4/0x2a0 [ 47.543053] [] notifier_call_chain+0x8b/0x170 [ 47.549163] [] raw_notifier_call_chain+0x11/0x20 [ 47.555537] [] call_netdevice_notifiers_info+0x47/0x80 [ 47.562429] [] register_netdevice+0x8e8/0xd00 [ 47.568540] [] ? netdev_change_features+0x80/0x80 [ 47.574996] [] ? dev_get_nest_level+0x10c/0x1a0 [ 47.581281] [] macvlan_common_newlink+0x8b9/0x1090 [ 47.587826] [] macvtap_newlink+0xbf/0x110 [ 47.593717] [] ? __netlink_ns_capable+0xc7/0xf0 [ 47.600008] [] rtnl_newlink+0xd4b/0x1230 [ 47.605684] [] ? rtnl_link_ops_get+0x5d/0x90 [ 47.611708] [] ? rtnl_newlink+0x319/0x1230 [ 47.617561] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 47.624281] [] ? rtnl_setlink+0x2f0/0x2f0 [ 47.630056] [] ? __kernel_text_address+0x61/0xa0 [ 47.636429] [] ? print_context_stack+0x6f/0xc0 [ 47.642626] [] ? __module_text_address+0x13/0x150 [ 47.649084] [] ? __module_text_address+0x13/0x150 [ 47.655556] [] ? is_module_text_address+0x2a/0x50 [ 47.662026] [] ? __lock_acquire+0x15c3/0x5990 [ 47.668144] [] ? __lock_acquire+0x9c9/0x5990 [ 47.674177] [] ? __netlink_ns_capable+0xc7/0xf0 [ 47.680470] [] rtnetlink_rcv_msg+0x222/0x680 [ 47.686596] [] ? trace_hardirqs_on_caller+0x49e/0x5c0 [ 47.693401] [] ? rtnetlink_rcv+0x30/0x30 [ 47.699078] [] ? mutex_lock_nested+0x5fd/0xb30 [ 47.705279] [] ? rtnetlink_rcv+0x16/0x30 [ 47.710963] [] ? netlink_seq_start+0xe0/0xe0 [ 47.716985] [] ? netlink_deliver_tap+0x73/0x850 [ 47.723309] [] netlink_rcv_skb+0x242/0x350 [ 47.729172] [] ? rtnetlink_rcv+0x30/0x30 [ 47.734849] [] rtnetlink_rcv+0x25/0x30 [ 47.740353] [] netlink_unicast+0x3da/0x560 [ 47.746206] [] ? netlink_sendskb+0x40/0x40 [ 47.752188] [] netlink_sendmsg+0x9bb/0xb40 [ 47.758048] [] ? nlmsg_notify+0xf0/0xf0 [ 47.763645] [] ? __might_fault+0xf1/0x1b0 [ 47.769539] [] ? nlmsg_notify+0xf0/0xf0 [ 47.775134] [] sock_sendmsg+0xb5/0xf0 [ 47.780600] [] SyS_sendto+0x1ca/0x290 [ 47.786025] [] ? SyS_getpeername+0x240/0x240 [ 47.792053] [] ? mntput_no_expire+0xce/0x600 [ 47.798082] [] ? mnt_get_count+0x1c0/0x1c0 [ 47.803939] [] ? mntput+0x52/0x70 [ 47.809017] [] ? task_work_run+0x14a/0x200 [ 47.814880] [] ? trace_hardirqs_on_caller+0x49e/0x5c0 [ 47.821726] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 47.828276] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 47.836233] Kernel Offset: disabled