Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 syzkaller login: [ 30.752367] IPVS: Creating netns size=2712 id=1 [ 30.757115] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.10.61' (ECDSA) to the list of known hosts. 2020/08/05 21:48:51 parsed 1 programs 2020/08/05 21:48:51 executed programs: 0 [ 38.394961] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 38.405384] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 38.418471] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 38.437974] IPVS: Creating netns size=2712 id=2 [ 38.446326] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 38.454556] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 38.458284] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 38.467555] IPVS: ftp: loaded support on port[0] = 21 [ 38.540038] IPVS: Creating netns size=2712 id=3 [ 38.545745] IPVS: ftp: loaded support on port[0] = 21 [ 38.680617] chnl_net:caif_netlink_parms(): no params data found [ 38.716565] IPVS: Creating netns size=2712 id=4 [ 38.721408] IPVS: ftp: loaded support on port[0] = 21 [ 38.919991] chnl_net:caif_netlink_parms(): no params data found [ 38.921575] IPVS: Creating netns size=2712 id=5 [ 38.921693] IPVS: ftp: loaded support on port[0] = 21 [ 39.024290] bridge0: port 1(bridge_slave_0) entered blocking state [ 39.030775] bridge0: port 1(bridge_slave_0) entered disabled state [ 39.040352] device bridge_slave_0 entered promiscuous mode [ 39.064757] bridge0: port 2(bridge_slave_1) entered blocking state [ 39.071116] bridge0: port 2(bridge_slave_1) entered disabled state [ 39.080424] device bridge_slave_1 entered promiscuous mode [ 39.181593] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 39.202694] IPVS: Creating netns size=2712 id=6 [ 39.207447] IPVS: ftp: loaded support on port[0] = 21 [ 39.274968] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 39.488054] chnl_net:caif_netlink_parms(): no params data found [ 39.550487] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 39.576092] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 39.620904] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 39.641942] IPVS: Creating netns size=2712 id=7 [ 39.647350] IPVS: ftp: loaded support on port[0] = 21 [ 39.685607] chnl_net:caif_netlink_parms(): no params data found [ 39.700542] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 39.714674] bridge0: port 1(bridge_slave_0) entered blocking state [ 39.721037] bridge0: port 1(bridge_slave_0) entered disabled state [ 39.730454] device bridge_slave_0 entered promiscuous mode [ 39.738336] bridge0: port 2(bridge_slave_1) entered blocking state [ 39.744744] bridge0: port 2(bridge_slave_1) entered disabled state [ 39.753812] device bridge_slave_1 entered promiscuous mode [ 39.910095] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 39.936890] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.039831] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 40.134497] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 40.165029] bridge0: port 1(bridge_slave_0) entered blocking state [ 40.171877] bridge0: port 1(bridge_slave_0) entered disabled state [ 40.180632] device bridge_slave_0 entered promiscuous mode [ 40.213117] chnl_net:caif_netlink_parms(): no params data found [ 40.227886] bridge0: port 2(bridge_slave_1) entered blocking state [ 40.234732] bridge0: port 2(bridge_slave_1) entered disabled state [ 40.244360] device bridge_slave_1 entered promiscuous mode [ 40.428769] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 40.507091] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.559193] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 40.578049] bridge0: port 1(bridge_slave_0) entered blocking state [ 40.585027] bridge0: port 1(bridge_slave_0) entered disabled state [ 40.594323] device bridge_slave_0 entered promiscuous mode [ 40.659273] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 40.668608] bridge0: port 2(bridge_slave_1) entered blocking state [ 40.676803] bridge0: port 2(bridge_slave_1) entered disabled state [ 40.686180] device bridge_slave_1 entered promiscuous mode [ 40.875926] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 40.918583] chnl_net:caif_netlink_parms(): no params data found [ 40.935848] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.944785] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.029307] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.036642] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 41.097455] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 41.124993] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.131692] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.140890] device bridge_slave_0 entered promiscuous mode [ 41.209406] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.216610] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.226029] device bridge_slave_1 entered promiscuous mode [ 41.273534] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 41.340409] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 41.373331] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 41.383269] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 41.430910] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.449585] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 41.461488] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.721343] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 41.739097] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.778466] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 41.797662] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.805055] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.811605] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.821030] device bridge_slave_0 entered promiscuous mode [ 41.893034] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.899448] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.908771] device bridge_slave_1 entered promiscuous mode [ 42.056174] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.065403] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 42.081995] ------------[ cut here ]------------ [ 42.086828] WARNING: CPU: 1 PID: 5890 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 42.095137] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 42.102336] Kernel panic - not syncing: panic_on_warn set ... [ 42.102336] [ 42.109680] CPU: 1 PID: 5890 Comm: syz-executor.1 Not tainted 4.6.0-syzkaller #0 [ 42.117196] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.126520] 0000000000000000 ffff8800b2596fc8 ffffffff82c65e52 ffffffff85c81040 [ 42.134553] ffff8800b25970a0 ffffffff85d2bb80 ffffffff8191bd7b 0000000000000009 [ 42.142556] ffff8800b2597090 ffffffff8160d884 0000000041b58ab3 ffffffff868f8c5a [ 42.150532] Call Trace: [ 42.153091] [] dump_stack+0x136/0x1d4 [ 42.158507] [] ? sysfs_warn_dup+0x7b/0xa0 [ 42.164271] [] panic+0x1af/0x348 [ 42.169253] [] ? to_vmem_altmap+0x125/0x125 [ 42.175222] [] ? sysfs_warn_dup+0x7b/0xa0 [ 42.180987] [] __warn+0x18d/0x1b0 [ 42.186056] [] warn_slowpath_fmt+0x92/0xb0 [ 42.191923] [] ? __warn+0x1b0/0x1b0 [ 42.197167] [] ? kernfs_path_from_node+0x4a/0x60 [ 42.203539] [] sysfs_warn_dup+0x7b/0xa0 [ 42.209296] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 42.216283] [] sysfs_create_link+0x43/0xb0 [ 42.222135] [] device_add+0x677/0x1350 [ 42.227640] [] ? device_private_init+0x180/0x180 [ 42.234017] [] ? kfree_const+0x1d/0x20 [ 42.239540] [] ? kobject_set_name_vargs+0xb4/0x130 [ 42.246093] [] device_create_groups_vargs+0x1c8/0x220 [ 42.252906] [] device_create+0x88/0xa0 [ 42.258515] [] ? device_create_vargs+0x20/0x20 [ 42.264726] [] ? macvlan_set_mac_address+0x150/0x150 [ 42.271459] [] macvtap_device_event+0x1c4/0x2a0 [ 42.277995] [] notifier_call_chain+0x8b/0x170 [ 42.284112] [] raw_notifier_call_chain+0x11/0x20 [ 42.290491] [] call_netdevice_notifiers_info+0x47/0x80 [ 42.297566] [] register_netdevice+0x8e8/0xd00 [ 42.303684] [] ? netdev_change_features+0x80/0x80 [ 42.310147] [] ? dev_get_nest_level+0x10c/0x1a0 [ 42.316447] [] macvlan_common_newlink+0x8b9/0x1090 [ 42.322992] [] macvtap_newlink+0xbf/0x110 [ 42.328878] [] ? __netlink_ns_capable+0xc7/0xf0 [ 42.335162] [] rtnl_newlink+0xd4b/0x1230 [ 42.340851] [] ? rtnl_link_ops_get+0x5d/0x90 [ 42.346878] [] ? rtnl_newlink+0x319/0x1230 [ 42.352732] [] ? load_balance+0xc07/0x1ef0 [ 42.358581] [] ? rtnl_setlink+0x2f0/0x2f0 [ 42.364362] [] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 42.371346] [] ? __netlink_ns_capable+0xc7/0xf0 [ 42.377632] [] rtnetlink_rcv_msg+0x222/0x680 [ 42.383656] [] ? rtnetlink_rcv+0x30/0x30 [ 42.389337] [] ? mutex_lock_nested+0x5fd/0xb30 [ 42.395535] [] ? rtnetlink_rcv+0x16/0x30 [ 42.401212] [] ? netlink_seq_start+0xe0/0xe0 [ 42.407257] [] netlink_rcv_skb+0x242/0x350 [ 42.413108] [] ? rtnetlink_rcv+0x30/0x30 [ 42.418784] [] rtnetlink_rcv+0x25/0x30 [ 42.424287] [] netlink_unicast+0x3da/0x560 [ 42.430139] [] ? netlink_sendskb+0x40/0x40 [ 42.435990] [] netlink_sendmsg+0x9bb/0xb40 [ 42.441860] [] ? nlmsg_notify+0xf0/0xf0 [ 42.447454] [] ? __might_fault+0xf1/0x1b0 [ 42.453238] [] ? security_socket_sendmsg+0x6a/0xa0 [ 42.459792] [] ? nlmsg_notify+0xf0/0xf0 [ 42.465395] [] sock_sendmsg+0xb5/0xf0 [ 42.470817] [] SyS_sendto+0x1ca/0x290 [ 42.476272] [] ? SyS_getpeername+0x240/0x240 [ 42.482354] [] ? kmem_cache_free+0x312/0x430 [ 42.488385] [] ? mntput_no_expire+0xce/0x600 [ 42.494421] [] ? mnt_get_count+0x1c0/0x1c0 [ 42.500277] [] ? mntput+0x52/0x70 [ 42.505352] [] ? task_work_run+0x14a/0x200 [ 42.511205] [] ? trace_hardirqs_off+0xd/0x10 [ 42.517233] [] ? exit_to_usermode_loop+0x112/0x1c0 [ 42.523783] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 42.530337] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 42.538041] Kernel Offset: disabled