[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 syzkaller login: [ 36.081358] IPVS: Creating netns size=2712 id=1 [ 36.086170] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.0.18' (ECDSA) to the list of known hosts. 2020/08/17 07:45:27 parsed 1 programs 2020/08/17 07:45:27 executed programs: 0 [ 43.978252] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 44.000666] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 44.013564] IPVS: Creating netns size=2712 id=2 [ 44.013711] IPVS: ftp: loaded support on port[0] = 21 [ 44.042600] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 44.062418] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 44.071735] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 44.089454] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 44.161134] IPVS: Creating netns size=2712 id=3 [ 44.166148] IPVS: ftp: loaded support on port[0] = 21 [ 44.318530] chnl_net:caif_netlink_parms(): no params data found [ 44.352688] IPVS: Creating netns size=2712 id=4 [ 44.357864] IPVS: ftp: loaded support on port[0] = 21 [ 44.578521] chnl_net:caif_netlink_parms(): no params data found [ 44.579106] IPVS: Creating netns size=2712 id=5 [ 44.579239] IPVS: ftp: loaded support on port[0] = 21 [ 44.719261] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.726001] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.735997] device bridge_slave_0 entered promiscuous mode [ 44.770265] bridge0: port 2(bridge_slave_1) entered blocking state [ 44.777574] bridge0: port 2(bridge_slave_1) entered disabled state [ 44.787242] device bridge_slave_1 entered promiscuous mode [ 44.937694] IPVS: Creating netns size=2712 id=6 [ 44.942770] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 44.950281] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 44.966730] IPVS: ftp: loaded support on port[0] = 21 [ 45.232386] chnl_net:caif_netlink_parms(): no params data found [ 45.276999] bridge0: port 1(bridge_slave_0) entered blocking state [ 45.283445] bridge0: port 1(bridge_slave_0) entered disabled state [ 45.292137] device bridge_slave_0 entered promiscuous mode [ 45.311052] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 45.319212] bridge0: port 2(bridge_slave_1) entered blocking state [ 45.325983] bridge0: port 2(bridge_slave_1) entered disabled state [ 45.335711] device bridge_slave_1 entered promiscuous mode [ 45.394532] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 45.403181] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 45.411435] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 45.451088] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 45.518888] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 45.540123] IPVS: Creating netns size=2712 id=7 [ 45.545468] IPVS: ftp: loaded support on port[0] = 21 [ 45.545602] chnl_net:caif_netlink_parms(): no params data found [ 45.612862] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 45.690402] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 46.024099] bridge0: port 1(bridge_slave_0) entered blocking state [ 46.030468] bridge0: port 1(bridge_slave_0) entered disabled state [ 46.040132] device bridge_slave_0 entered promiscuous mode [ 46.069754] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 46.086593] bridge0: port 2(bridge_slave_1) entered blocking state [ 46.092948] bridge0: port 2(bridge_slave_1) entered disabled state [ 46.104214] device bridge_slave_1 entered promiscuous mode [ 46.129851] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 46.137631] chnl_net:caif_netlink_parms(): no params data found [ 46.276721] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 46.366134] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 46.426288] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 46.459106] bridge0: port 1(bridge_slave_0) entered blocking state [ 46.465734] bridge0: port 1(bridge_slave_0) entered disabled state [ 46.475622] device bridge_slave_0 entered promiscuous mode [ 46.482898] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 46.555194] bridge0: port 2(bridge_slave_1) entered blocking state [ 46.561554] bridge0: port 2(bridge_slave_1) entered disabled state [ 46.572259] device bridge_slave_1 entered promiscuous mode [ 46.617514] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 46.697630] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 46.710054] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 46.992115] chnl_net:caif_netlink_parms(): no params data found [ 47.077966] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 47.146543] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 47.160719] bridge0: port 1(bridge_slave_0) entered blocking state [ 47.168884] bridge0: port 1(bridge_slave_0) entered disabled state [ 47.178514] device bridge_slave_0 entered promiscuous mode [ 47.278129] bridge0: port 2(bridge_slave_1) entered blocking state [ 47.285339] bridge0: port 2(bridge_slave_1) entered disabled state [ 47.295856] device bridge_slave_1 entered promiscuous mode [ 47.392310] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 47.461786] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 47.470741] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 47.484222] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 47.544458] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 47.558368] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 47.660677] 8021q: adding VLAN 0 to HW filter on device bond0 [ 47.670002] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 47.680915] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 47.753940] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 47.765584] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 47.873413] bridge0: port 1(bridge_slave_0) entered blocking state [ 47.879787] bridge0: port 1(bridge_slave_0) entered disabled state [ 47.889303] device bridge_slave_0 entered promiscuous mode [ 47.933310] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 47.961446] bridge0: port 2(bridge_slave_1) entered blocking state [ 47.968568] bridge0: port 2(bridge_slave_1) entered disabled state [ 47.978680] device bridge_slave_1 entered promiscuous mode [ 48.107668] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 48.116293] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 48.146787] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 48.155547] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 48.184971] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 48.193857] bridge0: port 1(bridge_slave_0) entered blocking state [ 48.200193] bridge0: port 1(bridge_slave_0) entered forwarding state [ 48.208340] IPv6: ADDRCONF(NETDEV_CHANGE): bridge0: link becomes ready [ 48.304642] ------------[ cut here ]------------ [ 48.309401] WARNING: CPU: 0 PID: 5883 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 48.318414] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 48.325492] Kernel panic - not syncing: panic_on_warn set ... [ 48.325492] [ 48.332841] CPU: 0 PID: 5883 Comm: syz-executor.5 Not tainted 4.6.0-syzkaller #0 [ 48.340348] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.349670] 0000000000000000 ffff8800b245efc8 ffffffff82c65e52 ffffffff85c81040 [ 48.357654] ffff8800b245f0a0 ffffffff85d2bb80 ffffffff8191bd7b 0000000000000009 [ 48.365623] ffff8800b245f090 ffffffff8160d884 0000000041b58ab3 ffffffff868f8c5a [ 48.373596] Call Trace: [ 48.376155] [] dump_stack+0x136/0x1d4 [ 48.381581] [] ? sysfs_warn_dup+0x7b/0xa0 [ 48.387357] [] panic+0x1af/0x348 [ 48.392384] [] ? to_vmem_altmap+0x125/0x125 [ 48.398332] [] ? sysfs_warn_dup+0x7b/0xa0 [ 48.404105] [] __warn+0x18d/0x1b0 [ 48.409176] [] warn_slowpath_fmt+0x92/0xb0 [ 48.415028] [] ? __warn+0x1b0/0x1b0 [ 48.420273] [] ? kernfs_path_from_node+0x4a/0x60 [ 48.426657] [] sysfs_warn_dup+0x7b/0xa0 [ 48.432254] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 48.439233] [] sysfs_create_link+0x43/0xb0 [ 48.445085] [] device_add+0x677/0x1350 [ 48.450590] [] ? device_private_init+0x180/0x180 [ 48.457050] [] ? kfree_const+0x1d/0x20 [ 48.462555] [] ? kobject_set_name_vargs+0xb4/0x130 [ 48.469103] [] device_create_groups_vargs+0x1c8/0x220 [ 48.479641] [] device_create+0x88/0xa0 [ 48.485145] [] ? device_create_vargs+0x20/0x20 [ 48.491345] [] ? macvlan_set_mac_address+0x150/0x150 [ 48.498064] [] macvtap_device_event+0x1c4/0x2a0 [ 48.504349] [] notifier_call_chain+0x8b/0x170 [ 48.510458] [] raw_notifier_call_chain+0x11/0x20 [ 48.516832] [] call_netdevice_notifiers_info+0x47/0x80 [ 48.523727] [] register_netdevice+0x8e8/0xd00 [ 48.529838] [] ? netdev_change_features+0x80/0x80 [ 48.536296] [] ? dev_get_nest_level+0x10c/0x1a0 [ 48.542588] [] macvlan_common_newlink+0x8b9/0x1090 [ 48.549152] [] macvtap_newlink+0xbf/0x110 [ 48.554918] [] ? __netlink_ns_capable+0xc7/0xf0 [ 48.561221] [] rtnl_newlink+0xd4b/0x1230 [ 48.566900] [] ? rtnl_link_ops_get+0x5d/0x90 [ 48.572926] [] ? rtnl_newlink+0x319/0x1230 [ 48.578795] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 48.585515] [] ? rtnl_setlink+0x2f0/0x2f0 [ 48.591279] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 48.598000] [] ? __lock_acquire+0x15c3/0x5990 [ 48.604114] [] ? cpuacct_charge+0x189/0x300 [ 48.610051] [] ? cpuacct_css_alloc+0x160/0x160 [ 48.616262] [] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 48.623256] [] ? __netlink_ns_capable+0xc7/0xf0 [ 48.629540] [] rtnetlink_rcv_msg+0x222/0x680 [ 48.635564] [] ? trace_hardirqs_on_caller+0x49e/0x5c0 [ 48.642369] [] ? rtnetlink_rcv+0x30/0x30 [ 48.648047] [] ? mutex_lock_nested+0x5fd/0xb30 [ 48.654243] [] ? rtnetlink_rcv+0x16/0x30 [ 48.659919] [] ? netlink_seq_start+0xe0/0xe0 [ 48.665945] [] netlink_rcv_skb+0x242/0x350 [ 48.671795] [] ? rtnetlink_rcv+0x30/0x30 [ 48.677472] [] rtnetlink_rcv+0x25/0x30 [ 48.682975] [] netlink_unicast+0x3da/0x560 [ 48.688824] [] ? netlink_sendskb+0x40/0x40 [ 48.694688] [] netlink_sendmsg+0x9bb/0xb40 [ 48.700539] [] ? nlmsg_notify+0xf0/0xf0 [ 48.706129] [] ? __might_fault+0xf1/0x1b0 [ 48.711892] [] ? nlmsg_notify+0xf0/0xf0 [ 48.717484] [] sock_sendmsg+0xb5/0xf0 [ 48.722901] [] SyS_sendto+0x1ca/0x290 [ 48.728339] [] ? SyS_getpeername+0x240/0x240 [ 48.734364] [] ? mntput_no_expire+0xce/0x600 [ 48.740387] [] ? mnt_get_count+0x1c0/0x1c0 [ 48.746236] [] ? mntput+0x52/0x70 [ 48.751305] [] ? task_work_run+0x14a/0x200 [ 48.757156] [] ? trace_hardirqs_on_caller+0x49e/0x5c0 [ 48.763963] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 48.770510] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 48.778441] Kernel Offset: disabled