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: [ 33.627121] IPVS: Creating netns size=2712 id=1 [ 33.632878] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.10.51' (ECDSA) to the list of known hosts. 2020/09/30 00:35:34 parsed 1 programs 2020/09/30 00:35:34 executed programs: 0 [ 41.014170] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 41.035350] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 41.045402] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 41.061125] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 41.075276] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 41.084968] IPVS: Creating netns size=2712 id=2 [ 41.085427] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 41.097057] IPVS: ftp: loaded support on port[0] = 21 [ 41.169281] IPVS: Creating netns size=2712 id=3 [ 41.174107] IPVS: ftp: loaded support on port[0] = 21 [ 41.319690] chnl_net:caif_netlink_parms(): no params data found [ 41.335122] IPVS: Creating netns size=2712 id=4 [ 41.340845] IPVS: ftp: loaded support on port[0] = 21 [ 41.530369] IPVS: Creating netns size=2712 id=5 [ 41.535195] IPVS: ftp: loaded support on port[0] = 21 [ 41.590248] chnl_net:caif_netlink_parms(): no params data found [ 41.630023] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.636689] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.645271] device bridge_slave_0 entered promiscuous mode [ 41.653554] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.660488] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.669482] device bridge_slave_1 entered promiscuous mode [ 41.795312] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 41.829865] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 41.851836] IPVS: Creating netns size=2712 id=6 [ 41.857016] IPVS: ftp: loaded support on port[0] = 21 [ 42.153535] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.160062] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.169618] device bridge_slave_0 entered promiscuous mode [ 42.219056] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.226108] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.234716] device bridge_slave_1 entered promiscuous mode [ 42.274099] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 42.316741] chnl_net:caif_netlink_parms(): no params data found [ 42.331710] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 42.350665] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.367817] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.375071] chnl_net:caif_netlink_parms(): no params data found [ 42.393927] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.406286] IPVS: Creating netns size=2712 id=7 [ 42.411567] IPVS: ftp: loaded support on port[0] = 21 [ 42.441375] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.622129] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 42.741043] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 42.874968] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.881357] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.891194] device bridge_slave_0 entered promiscuous mode [ 42.899760] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.907551] chnl_net:caif_netlink_parms(): no params data found [ 42.934105] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.940572] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.949874] device bridge_slave_1 entered promiscuous mode [ 42.957066] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 43.190577] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 43.199928] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.207493] bridge0: port 1(bridge_slave_0) entered blocking state [ 43.213848] bridge0: port 1(bridge_slave_0) entered disabled state [ 43.222633] device bridge_slave_0 entered promiscuous mode [ 43.230861] bridge0: port 2(bridge_slave_1) entered blocking state [ 43.237278] bridge0: port 2(bridge_slave_1) entered disabled state [ 43.246135] device bridge_slave_1 entered promiscuous mode [ 43.274150] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 43.302799] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 43.433637] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 43.500087] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 43.673256] bridge0: port 1(bridge_slave_0) entered blocking state [ 43.680156] bridge0: port 1(bridge_slave_0) entered disabled state [ 43.689401] device bridge_slave_0 entered promiscuous mode [ 43.787372] bridge0: port 2(bridge_slave_1) entered blocking state [ 43.793757] bridge0: port 2(bridge_slave_1) entered disabled state [ 43.803804] device bridge_slave_1 entered promiscuous mode [ 43.852509] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 43.901661] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 43.910173] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 43.964826] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 44.004844] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 44.011594] chnl_net:caif_netlink_parms(): no params data found [ 44.098192] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 44.106559] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 44.226769] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 44.235013] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 44.296004] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 44.303424] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 44.407496] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 44.443118] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 44.588583] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 44.647756] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 44.667048] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.673425] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.683238] device bridge_slave_0 entered promiscuous mode [ 44.702111] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 44.750879] bridge0: port 2(bridge_slave_1) entered blocking state [ 44.757517] bridge0: port 2(bridge_slave_1) entered disabled state [ 44.766692] device bridge_slave_1 entered promiscuous mode [ 44.814542] ------------[ cut here ]------------ [ 44.819398] WARNING: CPU: 1 PID: 5905 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 44.827206] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 44.834294] Kernel panic - not syncing: panic_on_warn set ... [ 44.834294] [ 44.841638] CPU: 1 PID: 5905 Comm: syz-executor.5 Not tainted 4.6.0-syzkaller #0 [ 44.849149] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.858499] 0000000000000000 ffff8800b988efc8 ffffffff82e18b12 ffffffff85e81040 [ 44.866540] ffff8800b988f0a0 ffffffff85f2bc00 ffffffff8191bd7b 0000000000000009 [ 44.874546] ffff8800b988f090 ffffffff8160d884 0000000041b58ab3 ffffffff86b4158a [ 44.882543] Call Trace: [ 44.885113] [] dump_stack+0x136/0x1d4 [ 44.890541] [] ? sysfs_warn_dup+0x7b/0xa0 [ 44.896311] [] panic+0x1af/0x348 [ 44.901296] [] ? to_vmem_altmap+0x125/0x125 [ 44.907237] [] ? sysfs_warn_dup+0x7b/0xa0 [ 44.913010] [] __warn+0x18d/0x1b0 [ 44.918097] [] warn_slowpath_fmt+0x92/0xb0 [ 44.923952] [] ? __warn+0x1b0/0x1b0 [ 44.929196] [] ? kernfs_path_from_node+0x4a/0x60 [ 44.935589] [] sysfs_warn_dup+0x7b/0xa0 [ 44.941179] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 44.948177] [] sysfs_create_link+0x43/0xb0 [ 44.954046] [] device_add+0x677/0x1350 [ 44.959552] [] ? device_private_init+0x180/0x180 [ 44.965926] [] ? kfree_const+0x1d/0x20 [ 44.971456] [] ? kobject_set_name_vargs+0xb4/0x130 [ 44.978016] [] device_create_groups_vargs+0x1c8/0x220 [ 44.984823] [] device_create+0x88/0xa0 [ 44.990327] [] ? device_create_vargs+0x20/0x20 [ 44.996528] [] ? macvlan_set_mac_address+0x150/0x150 [ 45.003262] [] macvtap_device_event+0x1c4/0x2a0 [ 45.009551] [] notifier_call_chain+0x8b/0x170 [ 45.015666] [] raw_notifier_call_chain+0x11/0x20 [ 45.022056] [] call_netdevice_notifiers_info+0x47/0x80 [ 45.028969] [] register_netdevice+0x8e8/0xd00 [ 45.035089] [] ? netdev_change_features+0x80/0x80 [ 45.041547] [] ? dev_get_nest_level+0x10c/0x1a0 [ 45.047833] [] macvlan_common_newlink+0x8b9/0x1090 [ 45.054381] [] macvtap_newlink+0xbf/0x110 [ 45.060147] [] ? __netlink_ns_capable+0xc7/0xf0 [ 45.066447] [] rtnl_newlink+0xd4b/0x1230 [ 45.072124] [] ? rtnl_link_ops_get+0x5d/0x90 [ 45.078150] [] ? rtnl_newlink+0x319/0x1230 [ 45.084005] [] ? __enqueue_entity+0x134/0x230 [ 45.090118] [] ? rtnl_setlink+0x2f0/0x2f0 [ 45.095901] [] ? __kernel_text_address+0x61/0xa0 [ 45.102276] [] ? print_context_stack+0x6f/0xc0 [ 45.108477] [] ? __module_text_address+0x13/0x150 [ 45.114937] [] ? __module_text_address+0x13/0x150 [ 45.121414] [] ? is_module_text_address+0x2a/0x50 [ 45.127876] [] ? __netlink_ns_capable+0xc7/0xf0 [ 45.134164] [] rtnetlink_rcv_msg+0x222/0x680 [ 45.140191] [] ? rtnetlink_rcv+0x30/0x30 [ 45.145871] [] ? mutex_lock_nested+0x5fd/0xb30 [ 45.152084] [] ? rtnetlink_rcv+0x16/0x30 [ 45.157764] [] ? netlink_seq_start+0xe0/0xe0 [ 45.163964] [] ? netlink_deliver_tap+0x73/0x850 [ 45.170256] [] netlink_rcv_skb+0x242/0x350 [ 45.176125] [] ? rtnetlink_rcv+0x30/0x30 [ 45.181804] [] rtnetlink_rcv+0x25/0x30 [ 45.187309] [] netlink_unicast+0x3da/0x560 [ 45.193161] [] ? netlink_sendskb+0x40/0x40 [ 45.199017] [] netlink_sendmsg+0x9bb/0xb40 [ 45.204886] [] ? nlmsg_notify+0xf0/0xf0 [ 45.210480] [] ? __might_fault+0xf1/0x1b0 [ 45.216269] [] ? security_socket_sendmsg+0x6a/0xa0 [ 45.222816] [] ? nlmsg_notify+0xf0/0xf0 [ 45.228409] [] sock_sendmsg+0xb5/0xf0 [ 45.233847] [] SyS_sendto+0x1ca/0x290 [ 45.239267] [] ? SyS_getpeername+0x240/0x240 [ 45.245294] [] ? kmem_cache_free+0x312/0x430 [ 45.251321] [] ? mntput_no_expire+0xce/0x600 [ 45.257347] [] ? mnt_get_count+0x1c0/0x1c0 [ 45.263199] [] ? mntput+0x52/0x70 [ 45.268270] [] ? task_work_run+0x14a/0x200 [ 45.274122] [] ? trace_hardirqs_off+0xd/0x10 [ 45.280150] [] ? exit_to_usermode_loop+0x112/0x1c0 [ 45.286695] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 45.293243] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 45.301324] Kernel Offset: disabled