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: [ 31.372158] IPVS: Creating netns size=2712 id=1 [ 31.376956] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.15.209' (ECDSA) to the list of known hosts. 2020/08/12 21:38:05 parsed 1 programs 2020/08/12 21:38:05 executed programs: 0 [ 38.775216] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 38.809372] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 38.823594] IPVS: Creating netns size=2712 id=2 [ 38.825935] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 38.831654] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 38.844204] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 38.851517] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 38.860997] IPVS: ftp: loaded support on port[0] = 21 [ 38.933869] IPVS: Creating netns size=2712 id=3 [ 38.938721] IPVS: ftp: loaded support on port[0] = 21 [ 39.083571] chnl_net:caif_netlink_parms(): no params data found [ 39.097737] IPVS: Creating netns size=2712 id=4 [ 39.102552] IPVS: ftp: loaded support on port[0] = 21 [ 39.306679] IPVS: Creating netns size=2712 id=5 [ 39.316649] IPVS: ftp: loaded support on port[0] = 21 [ 39.394943] bridge0: port 1(bridge_slave_0) entered blocking state [ 39.401597] bridge0: port 1(bridge_slave_0) entered disabled state [ 39.410930] device bridge_slave_0 entered promiscuous mode [ 39.453537] bridge0: port 2(bridge_slave_1) entered blocking state [ 39.460195] bridge0: port 2(bridge_slave_1) entered disabled state [ 39.470009] device bridge_slave_1 entered promiscuous mode [ 39.482450] chnl_net:caif_netlink_parms(): no params data found [ 39.620638] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 39.643469] chnl_net:caif_netlink_parms(): no params data found [ 39.659992] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 39.680314] IPVS: Creating netns size=2712 id=6 [ 39.685704] IPVS: ftp: loaded support on port[0] = 21 [ 40.019329] bridge0: port 1(bridge_slave_0) entered blocking state [ 40.025753] bridge0: port 1(bridge_slave_0) entered disabled state [ 40.035704] IPVS: Creating netns size=2712 id=7 [ 40.038191] device bridge_slave_0 entered promiscuous mode [ 40.040778] bridge0: port 2(bridge_slave_1) entered blocking state [ 40.040874] bridge0: port 2(bridge_slave_1) entered disabled state [ 40.044824] device bridge_slave_1 entered promiscuous mode [ 40.067736] IPVS: ftp: loaded support on port[0] = 21 [ 40.104490] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 40.113379] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 40.122178] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 40.143721] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 40.167471] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 40.196656] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.305668] chnl_net:caif_netlink_parms(): no params data found [ 40.524995] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 40.532625] bridge0: port 1(bridge_slave_0) entered blocking state [ 40.539366] bridge0: port 1(bridge_slave_0) entered disabled state [ 40.549152] device bridge_slave_0 entered promiscuous mode [ 40.573687] chnl_net:caif_netlink_parms(): no params data found [ 40.590699] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 40.598008] bridge0: port 2(bridge_slave_1) entered blocking state [ 40.604352] bridge0: port 2(bridge_slave_1) entered disabled state [ 40.613080] device bridge_slave_1 entered promiscuous mode [ 40.640068] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 40.717443] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 40.730438] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 40.789979] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.897506] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.025891] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.122547] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.128998] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.138466] device bridge_slave_0 entered promiscuous mode [ 41.223872] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.230327] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.239937] device bridge_slave_1 entered promiscuous mode [ 41.289951] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 41.312596] chnl_net:caif_netlink_parms(): no params data found [ 41.367623] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 41.409160] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 41.489492] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 41.536449] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.542878] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.552467] device bridge_slave_0 entered promiscuous mode [ 41.605249] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.611934] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.621220] device bridge_slave_1 entered promiscuous mode [ 41.692701] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 41.791515] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.803415] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 41.829942] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.850382] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 41.947960] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 41.987642] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.098451] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.104815] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.114083] device bridge_slave_0 entered promiscuous mode [ 42.121850] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.128887] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.137729] device bridge_slave_1 entered promiscuous mode [ 42.267609] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 42.274621] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 42.303823] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.328197] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.348810] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.357992] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 42.434372] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.605152] ------------[ cut here ]------------ [ 42.609920] WARNING: CPU: 1 PID: 5870 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 42.618182] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 42.625221] Kernel panic - not syncing: panic_on_warn set ... [ 42.625221] [ 42.632572] CPU: 1 PID: 5870 Comm: syz-executor.4 Not tainted 4.6.0-syzkaller #0 [ 42.640073] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.649403] 0000000000000000 ffff8800b19defc8 ffffffff82c65e52 ffffffff85c81040 [ 42.657403] ffff8800b19df0a0 ffffffff85d2bb80 ffffffff8191bd7b 0000000000000009 [ 42.665376] ffff8800b19df090 ffffffff8160d884 0000000041b58ab3 ffffffff868f3a9a [ 42.673488] Call Trace: [ 42.676047] [] dump_stack+0x136/0x1d4 [ 42.681506] [] ? sysfs_warn_dup+0x7b/0xa0 [ 42.687272] [] panic+0x1af/0x348 [ 42.692256] [] ? to_vmem_altmap+0x125/0x125 [ 42.698220] [] ? sysfs_warn_dup+0x7b/0xa0 [ 42.703986] [] __warn+0x18d/0x1b0 [ 42.709056] [] warn_slowpath_fmt+0x92/0xb0 [ 42.714912] [] ? __warn+0x1b0/0x1b0 [ 42.720165] [] ? kernfs_path_from_node+0x4a/0x60 [ 42.726592] [] sysfs_warn_dup+0x7b/0xa0 [ 42.732180] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 42.739164] [] sysfs_create_link+0x43/0xb0 [ 42.745019] [] device_add+0x677/0x1350 [ 42.750524] [] ? device_private_init+0x180/0x180 [ 42.756898] [] ? kfree_const+0x1d/0x20 [ 42.762404] [] ? kobject_set_name_vargs+0xb4/0x130 [ 42.768949] [] device_create_groups_vargs+0x1c8/0x220 [ 42.775756] [] device_create+0x88/0xa0 [ 42.781258] [] ? device_create_vargs+0x20/0x20 [ 42.787473] [] ? macvlan_set_mac_address+0x150/0x150 [ 42.794196] [] macvtap_device_event+0x1c4/0x2a0 [ 42.800482] [] notifier_call_chain+0x8b/0x170 [ 42.807723] [] raw_notifier_call_chain+0x11/0x20 [ 42.814095] [] call_netdevice_notifiers_info+0x47/0x80 [ 42.820989] [] register_netdevice+0x8e8/0xd00 [ 42.827104] [] ? netdev_change_features+0x80/0x80 [ 42.833561] [] ? dev_get_nest_level+0x10c/0x1a0 [ 42.840197] [] macvlan_common_newlink+0x8b9/0x1090 [ 42.846741] [] macvtap_newlink+0xbf/0x110 [ 42.852505] [] ? __netlink_ns_capable+0xc7/0xf0 [ 42.858789] [] rtnl_newlink+0xd4b/0x1230 [ 42.864466] [] ? rtnl_link_ops_get+0x5d/0x90 [ 42.870492] [] ? rtnl_newlink+0x319/0x1230 [ 42.876344] [] ? find_next_bit+0x15/0x20 [ 42.882021] [] ? rtnl_setlink+0x2f0/0x2f0 [ 42.887785] [] ? cpuacct_css_alloc+0x160/0x160 [ 42.893997] [] ? update_blocked_averages+0x8f7/0x1540 [ 42.900803] [] ? find_busiest_group+0x2510/0x2510 [ 42.907261] [] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 42.914244] [] ? __netlink_ns_capable+0xc7/0xf0 [ 42.920531] [] rtnetlink_rcv_msg+0x222/0x680 [ 42.926555] [] ? rtnetlink_rcv+0x30/0x30 [ 42.932235] [] ? mutex_lock_nested+0x5fd/0xb30 [ 42.938433] [] ? rtnetlink_rcv+0x16/0x30 [ 42.944110] [] ? netlink_seq_start+0xe0/0xe0 [ 42.950135] [] netlink_rcv_skb+0x242/0x350 [ 42.955988] [] ? rtnetlink_rcv+0x30/0x30 [ 42.961663] [] rtnetlink_rcv+0x25/0x30 [ 42.967170] [] netlink_unicast+0x3da/0x560 [ 42.973020] [] ? netlink_sendskb+0x40/0x40 [ 42.978874] [] netlink_sendmsg+0x9bb/0xb40 [ 42.984728] [] ? nlmsg_notify+0xf0/0xf0 [ 42.990324] [] ? __might_fault+0xf1/0x1b0 [ 42.996089] [] ? security_socket_sendmsg+0x6a/0xa0 [ 43.002632] [] ? nlmsg_notify+0xf0/0xf0 [ 43.008224] [] sock_sendmsg+0xb5/0xf0 [ 43.013640] [] SyS_sendto+0x1ca/0x290 [ 43.019056] [] ? SyS_getpeername+0x240/0x240 [ 43.025082] [] ? kmem_cache_free+0x312/0x430 [ 43.031108] [] ? mntput_no_expire+0xce/0x600 [ 43.037143] [] ? mnt_get_count+0x1c0/0x1c0 [ 43.042994] [] ? mntput+0x52/0x70 [ 43.048066] [] ? task_work_run+0x14a/0x200 [ 43.053933] [] ? trace_hardirqs_off+0xd/0x10 [ 43.059958] [] ? exit_to_usermode_loop+0x112/0x1c0 [ 43.066506] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 43.073055] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 43.080681] Kernel Offset: disabled