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: [ 33.214354] IPVS: Creating netns size=2712 id=1 [ 33.219279] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.0.198' (ECDSA) to the list of known hosts. 2020/08/10 23:38:04 parsed 1 programs 2020/08/10 23:38:04 executed programs: 0 [ 41.027346] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 41.039407] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 41.049313] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 41.059182] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 41.070575] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 41.078319] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 41.094462] IPVS: Creating netns size=2712 id=2 [ 41.099205] IPVS: ftp: loaded support on port[0] = 21 [ 41.175824] IPVS: Creating netns size=2712 id=3 [ 41.181997] IPVS: ftp: loaded support on port[0] = 21 [ 41.335377] chnl_net:caif_netlink_parms(): no params data found [ 41.375437] IPVS: Creating netns size=2712 id=4 [ 41.380525] IPVS: ftp: loaded support on port[0] = 21 [ 41.632569] IPVS: Creating netns size=2712 id=5 [ 41.635435] chnl_net:caif_netlink_parms(): no params data found [ 41.645229] IPVS: ftp: loaded support on port[0] = 21 [ 41.793218] chnl_net:caif_netlink_parms(): no params data found [ 41.895619] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.902306] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.913379] device bridge_slave_0 entered promiscuous mode [ 41.974515] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.981041] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.991272] device bridge_slave_1 entered promiscuous mode [ 42.075443] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.082485] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.092073] device bridge_slave_0 entered promiscuous mode [ 42.102650] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.115498] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.130384] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.136798] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.146271] device bridge_slave_1 entered promiscuous mode [ 42.240162] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.281721] IPVS: Creating netns size=2712 id=6 [ 42.286964] IPVS: ftp: loaded support on port[0] = 21 [ 42.307918] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.387295] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.393776] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.403419] device bridge_slave_0 entered promiscuous mode [ 42.482025] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.489070] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.497940] device bridge_slave_1 entered promiscuous mode [ 42.506052] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 42.563073] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 42.661644] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.741063] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.757870] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.801150] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.830065] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.895292] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.938948] IPVS: Creating netns size=2712 id=7 [ 42.943819] IPVS: ftp: loaded support on port[0] = 21 [ 42.995558] chnl_net:caif_netlink_parms(): no params data found [ 43.017173] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.061304] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 43.141424] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.179597] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 43.339493] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 43.378307] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 43.479385] chnl_net:caif_netlink_parms(): no params data found [ 43.602885] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.610320] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 43.724673] bridge0: port 1(bridge_slave_0) entered blocking state [ 43.732064] bridge0: port 1(bridge_slave_0) entered disabled state [ 43.741805] device bridge_slave_0 entered promiscuous mode [ 43.801583] bridge0: port 2(bridge_slave_1) entered blocking state [ 43.808091] bridge0: port 2(bridge_slave_1) entered disabled state [ 43.816856] device bridge_slave_1 entered promiscuous mode [ 43.933362] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 44.004680] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 44.330095] chnl_net:caif_netlink_parms(): no params data found [ 44.348806] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 44.408157] bridge0: port 1(bridge_slave_0) entered blocking state [ 44.414627] bridge0: port 1(bridge_slave_0) entered disabled state [ 44.426373] device bridge_slave_0 entered promiscuous mode [ 44.460766] ------------[ cut here ]------------ [ 44.465556] WARNING: CPU: 0 PID: 5884 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 44.473599] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 44.480645] Kernel panic - not syncing: panic_on_warn set ... [ 44.480645] [ 44.487994] CPU: 0 PID: 5884 Comm: syz-executor.4 Not tainted 4.6.0-syzkaller #0 [ 44.495559] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.504882] 0000000000000000 ffff880129476fc8 ffffffff82c65e52 ffffffff85c81040 [ 44.512858] ffff8801294770a0 ffffffff85d2bb80 ffffffff8191bd7b 0000000000000009 [ 44.520822] ffff880129477090 ffffffff8160d884 0000000041b58ab3 ffffffff868f8c5a [ 44.528958] Call Trace: [ 44.531641] [] dump_stack+0x136/0x1d4 [ 44.537366] [] ? sysfs_warn_dup+0x7b/0xa0 [ 44.543139] [] panic+0x1af/0x348 [ 44.548147] [] ? to_vmem_altmap+0x125/0x125 [ 44.554087] [] ? sysfs_warn_dup+0x7b/0xa0 [ 44.559854] [] __warn+0x18d/0x1b0 [ 44.564927] [] warn_slowpath_fmt+0x92/0xb0 [ 44.570795] [] ? __warn+0x1b0/0x1b0 [ 44.576047] [] ? kernfs_path_from_node+0x4a/0x60 [ 44.582427] [] sysfs_warn_dup+0x7b/0xa0 [ 44.588160] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 44.595269] [] sysfs_create_link+0x43/0xb0 [ 44.601122] [] device_add+0x677/0x1350 [ 44.606886] [] ? device_private_init+0x180/0x180 [ 44.613263] [] ? kfree_const+0x1d/0x20 [ 44.618785] [] ? kobject_set_name_vargs+0xb4/0x130 [ 44.625355] [] device_create_groups_vargs+0x1c8/0x220 [ 44.632175] [] device_create+0x88/0xa0 [ 44.637685] [] ? device_create_vargs+0x20/0x20 [ 44.643886] [] ? macvlan_set_mac_address+0x150/0x150 [ 44.650645] [] macvtap_device_event+0x1c4/0x2a0 [ 44.657054] [] notifier_call_chain+0x8b/0x170 [ 44.663234] [] raw_notifier_call_chain+0x11/0x20 [ 44.669615] [] call_netdevice_notifiers_info+0x47/0x80 [ 44.676509] [] register_netdevice+0x8e8/0xd00 [ 44.682669] [] ? netdev_change_features+0x80/0x80 [ 44.689129] [] ? dev_get_nest_level+0x10c/0x1a0 [ 44.695415] [] macvlan_common_newlink+0x8b9/0x1090 [ 44.701968] [] macvtap_newlink+0xbf/0x110 [ 44.707734] [] ? __netlink_ns_capable+0xc7/0xf0 [ 44.714019] [] rtnl_newlink+0xd4b/0x1230 [ 44.719696] [] ? rtnl_link_ops_get+0x5d/0x90 [ 44.725720] [] ? rtnl_newlink+0x319/0x1230 [ 44.731615] [] ? find_next_bit+0x15/0x20 [ 44.737422] [] ? rtnl_setlink+0x2f0/0x2f0 [ 44.743242] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 44.749968] [] ? __lock_acquire+0x15c3/0x5990 [ 44.756084] [] ? update_blocked_averages+0x8f7/0x1540 [ 44.762921] [] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 44.770058] [] ? __netlink_ns_capable+0xc7/0xf0 [ 44.776354] [] rtnetlink_rcv_msg+0x222/0x680 [ 44.782426] [] ? trace_hardirqs_on_caller+0x49e/0x5c0 [ 44.789380] [] ? rtnetlink_rcv+0x30/0x30 [ 44.795062] [] ? mutex_lock_nested+0x5fd/0xb30 [ 44.801260] [] ? rtnetlink_rcv+0x16/0x30 [ 44.806938] [] ? netlink_seq_start+0xe0/0xe0 [ 44.812963] [] netlink_rcv_skb+0x242/0x350 [ 44.818815] [] ? rtnetlink_rcv+0x30/0x30 [ 44.824494] [] rtnetlink_rcv+0x25/0x30 [ 44.829997] [] netlink_unicast+0x3da/0x560 [ 44.835847] [] ? netlink_sendskb+0x40/0x40 [ 44.846311] [] netlink_sendmsg+0x9bb/0xb40 [ 44.852184] [] ? nlmsg_notify+0xf0/0xf0 [ 44.857780] [] ? __might_fault+0xf1/0x1b0 [ 44.863543] [] ? nlmsg_notify+0xf0/0xf0 [ 44.869137] [] sock_sendmsg+0xb5/0xf0 [ 44.874565] [] SyS_sendto+0x1ca/0x290 [ 44.879985] [] ? SyS_getpeername+0x240/0x240 [ 44.886010] [] ? mntput_no_expire+0xce/0x600 [ 44.892036] [] ? mnt_get_count+0x1c0/0x1c0 [ 44.897889] [] ? mntput+0x52/0x70 [ 44.902961] [] ? task_work_run+0x14a/0x200 [ 44.908813] [] ? trace_hardirqs_on_caller+0x49e/0x5c0 [ 44.915620] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 44.922182] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 44.930093] Kernel Offset: disabled