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: [ 31.602862] IPVS: Creating netns size=2712 id=1 [ 31.608208] IPVS: ftp: loaded support on port[0] = 21 Warning: Permanently added '10.128.0.107' (ECDSA) to the list of known hosts. 2020/07/17 17:33:24 parsed 1 programs 2020/07/17 17:33:24 executed programs: 0 [ 39.430685] IPv6: ADDRCONF(NETDEV_CHANGE): nr2: link becomes ready [ 39.453813] IPv6: ADDRCONF(NETDEV_CHANGE): nr0: link becomes ready [ 39.464429] IPv6: ADDRCONF(NETDEV_CHANGE): nr1: link becomes ready [ 39.475573] IPVS: Creating netns size=2712 id=2 [ 39.476047] IPv6: ADDRCONF(NETDEV_CHANGE): nr3: link becomes ready [ 39.480592] IPv6: ADDRCONF(NETDEV_CHANGE): nr4: link becomes ready [ 39.494162] IPVS: ftp: loaded support on port[0] = 21 [ 39.494298] IPv6: ADDRCONF(NETDEV_CHANGE): nr5: link becomes ready [ 39.575526] IPVS: Creating netns size=2712 id=3 [ 39.580383] IPVS: ftp: loaded support on port[0] = 21 [ 39.709462] chnl_net:caif_netlink_parms(): no params data found [ 39.760916] IPVS: Creating netns size=2712 id=4 [ 39.765830] IPVS: ftp: loaded support on port[0] = 21 [ 39.949164] IPVS: Creating netns size=2712 id=5 [ 39.955946] IPVS: ftp: loaded support on port[0] = 21 [ 40.014290] bridge0: port 1(bridge_slave_0) entered blocking state [ 40.021206] bridge0: port 1(bridge_slave_0) entered disabled state [ 40.030846] device bridge_slave_0 entered promiscuous mode [ 40.053472] bridge0: port 2(bridge_slave_1) entered blocking state [ 40.060283] bridge0: port 2(bridge_slave_1) entered disabled state [ 40.069653] device bridge_slave_1 entered promiscuous mode [ 40.098067] chnl_net:caif_netlink_parms(): no params data found [ 40.206338] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 40.223562] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.354805] IPVS: Creating netns size=2712 id=6 [ 40.359637] IPVS: ftp: loaded support on port[0] = 21 [ 40.519510] chnl_net:caif_netlink_parms(): no params data found [ 40.615447] bridge0: port 1(bridge_slave_0) entered blocking state [ 40.622056] bridge0: port 1(bridge_slave_0) entered disabled state [ 40.630676] device bridge_slave_0 entered promiscuous mode [ 40.675981] bridge0: port 2(bridge_slave_1) entered blocking state [ 40.682487] bridge0: port 2(bridge_slave_1) entered disabled state [ 40.692044] device bridge_slave_1 entered promiscuous mode [ 40.743883] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 40.764789] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 40.781846] batman_adv: Unable to register the batman interface 'batadv0': -12 [ 40.823774] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 40.833380] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 40.840917] chnl_net:caif_netlink_parms(): no params data found [ 40.845134] IPVS: Creating netns size=2712 id=7 [ 40.845248] IPVS: ftp: loaded support on port[0] = 21 [ 40.894443] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 41.082281] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.142894] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.326688] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 41.334362] chnl_net:caif_netlink_parms(): no params data found [ 41.352373] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.358793] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.371307] device bridge_slave_0 entered promiscuous mode [ 41.378808] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 41.427751] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.434289] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.443637] device bridge_slave_1 entered promiscuous mode [ 41.567838] bridge0: port 1(bridge_slave_0) entered blocking state [ 41.574933] bridge0: port 1(bridge_slave_0) entered disabled state [ 41.584148] device bridge_slave_0 entered promiscuous mode [ 41.649069] bridge0: port 2(bridge_slave_1) entered blocking state [ 41.655724] bridge0: port 2(bridge_slave_1) entered disabled state [ 41.665509] device bridge_slave_1 entered promiscuous mode [ 41.675160] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 41.744421] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 41.753194] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 41.761374] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 41.884088] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.015103] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.211785] chnl_net:caif_netlink_parms(): no params data found [ 42.252785] bridge0: port 1(bridge_slave_0) entered blocking state [ 42.259161] bridge0: port 1(bridge_slave_0) entered disabled state [ 42.269198] device bridge_slave_0 entered promiscuous mode [ 42.277224] bridge0: port 2(bridge_slave_1) entered blocking state [ 42.284172] bridge0: port 2(bridge_slave_1) entered disabled state [ 42.293370] device bridge_slave_1 entered promiscuous mode [ 42.380776] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.423309] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 42.436806] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.473000] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 42.612355] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.651033] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 42.658242] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 42.684836] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 42.771706] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 42.844059] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 42.864455] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready [ 42.873549] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready [ 42.881301] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 42.911530] IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready [ 43.043142] bridge0: port 1(bridge_slave_0) entered blocking state [ 43.051159] bridge0: port 1(bridge_slave_0) entered disabled state [ 43.060694] device bridge_slave_0 entered promiscuous mode [ 43.088191] bridge0: port 2(bridge_slave_1) entered blocking state [ 43.095597] bridge0: port 2(bridge_slave_1) entered disabled state [ 43.105237] device bridge_slave_1 entered promiscuous mode [ 43.180240] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready [ 43.230753] IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready [ 43.264729] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 43.308150] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 43.406615] ------------[ cut here ]------------ [ 43.411492] WARNING: CPU: 1 PID: 5877 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 [ 43.420082] sysfs: cannot create duplicate filename '/class/macvtap/tap50' [ 43.427252] Kernel panic - not syncing: panic_on_warn set ... [ 43.427252] [ 43.434685] CPU: 1 PID: 5877 Comm: syz-executor.4 Not tainted 4.6.0-syzkaller #0 [ 43.442529] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.451952] 0000000000000000 ffff88012889efc8 ffffffff82c65e52 ffffffff85c81040 [ 43.460039] ffff88012889f0a0 ffffffff85d2bb80 ffffffff8191bd7b 0000000000000009 [ 43.468275] ffff88012889f090 ffffffff8160d884 0000000041b58ab3 ffffffff868f3402 [ 43.476414] Call Trace: [ 43.478983] [] dump_stack+0x136/0x1d4 [ 43.484407] [] ? sysfs_warn_dup+0x7b/0xa0 [ 43.490185] [] panic+0x1af/0x348 [ 43.495278] [] ? to_vmem_altmap+0x125/0x125 [ 43.501242] [] ? sysfs_warn_dup+0x7b/0xa0 [ 43.507017] [] __warn+0x18d/0x1b0 [ 43.512097] [] warn_slowpath_fmt+0x92/0xb0 [ 43.517964] [] ? __warn+0x1b0/0x1b0 [ 43.523411] [] ? kernfs_path_from_node+0x4a/0x60 [ 43.529852] [] sysfs_warn_dup+0x7b/0xa0 [ 43.535452] [] sysfs_do_create_link_sd.isra.0+0xd1/0xf0 [ 43.542510] [] sysfs_create_link+0x43/0xb0 [ 43.548633] [] device_add+0x677/0x1350 [ 43.554146] [] ? device_private_init+0x180/0x180 [ 43.560528] [] ? kfree_const+0x1d/0x20 [ 43.566067] [] ? kobject_set_name_vargs+0xb4/0x130 [ 43.572640] [] device_create_groups_vargs+0x1c8/0x220 [ 43.579454] [] device_create+0x88/0xa0 [ 43.584981] [] ? device_create_vargs+0x20/0x20 [ 43.592438] [] ? macvlan_set_mac_address+0x150/0x150 [ 43.599317] [] macvtap_device_event+0x1c4/0x2a0 [ 43.605913] [] notifier_call_chain+0x8b/0x170 [ 43.612079] [] raw_notifier_call_chain+0x11/0x20 [ 43.618463] [] call_netdevice_notifiers_info+0x47/0x80 [ 43.625514] [] register_netdevice+0x8e8/0xd00 [ 43.631650] [] ? netdev_change_features+0x80/0x80 [ 43.638120] [] ? dev_get_nest_level+0x10c/0x1a0 [ 43.644458] [] macvlan_common_newlink+0x8b9/0x1090 [ 43.651183] [] macvtap_newlink+0xbf/0x110 [ 43.657074] [] ? __netlink_ns_capable+0xc7/0xf0 [ 43.663624] [] rtnl_newlink+0xd4b/0x1230 [ 43.669320] [] ? rtnl_link_ops_get+0x5d/0x90 [ 43.675479] [] ? rtnl_newlink+0x319/0x1230 [ 43.681356] [] ? load_balance+0x967/0x1ef0 [ 43.687221] [] ? rtnl_setlink+0x2f0/0x2f0 [ 43.693006] [] ? find_busiest_group+0x2510/0x2510 [ 43.699665] [] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 43.706657] [] ? __netlink_ns_capable+0xc7/0xf0 [ 43.713044] [] rtnetlink_rcv_msg+0x222/0x680 [ 43.719165] [] ? rtnetlink_rcv+0x30/0x30 [ 43.724851] [] ? mutex_lock_nested+0x5fd/0xb30 [ 43.731056] [] ? rtnetlink_rcv+0x16/0x30 [ 43.736761] [] ? netlink_seq_start+0xe0/0xe0 [ 43.742813] [] netlink_rcv_skb+0x242/0x350 [ 43.748672] [] ? rtnetlink_rcv+0x30/0x30 [ 43.754354] [] rtnetlink_rcv+0x25/0x30 [ 43.759865] [] netlink_unicast+0x3da/0x560 [ 43.765725] [] ? netlink_sendskb+0x40/0x40 [ 43.771589] [] netlink_sendmsg+0x9bb/0xb40 [ 43.777446] [] ? nlmsg_notify+0xf0/0xf0 [ 43.783485] [] ? __might_fault+0xf1/0x1b0 [ 43.789258] [] ? security_socket_sendmsg+0x6a/0xa0 [ 43.795898] [] ? nlmsg_notify+0xf0/0xf0 [ 43.801504] [] sock_sendmsg+0xb5/0xf0 [ 43.807016] [] SyS_sendto+0x1ca/0x290 [ 43.812547] [] ? SyS_getpeername+0x240/0x240 [ 43.818680] [] ? kmem_cache_free+0x312/0x430 [ 43.824891] [] ? mntput_no_expire+0xce/0x600 [ 43.831172] [] ? mnt_get_count+0x1c0/0x1c0 [ 43.837273] [] ? mntput+0x52/0x70 [ 43.842467] [] ? task_work_run+0x14a/0x200 [ 43.848393] [] ? trace_hardirqs_off+0xd/0x10 [ 43.854433] [] ? exit_to_usermode_loop+0x112/0x1c0 [ 43.861119] [] ? trace_hardirqs_on_thunk+0x1b/0x1d [ 43.867764] [] entry_SYSCALL_64_fastpath+0x23/0xc1 [ 43.876119] Kernel Offset: disabled