[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 60.212120][ T27] audit: type=1800 audit(1581997325.003:25): pid=8673 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 60.231597][ T27] audit: type=1800 audit(1581997325.003:26): pid=8673 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 60.278051][ T27] audit: type=1800 audit(1581997325.003:27): pid=8673 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 62.673696][ T8810] sshd (8810) used greatest stack depth: 23536 bytes left Warning: Permanently added '10.128.0.217' (ECDSA) to the list of known hosts. [ 69.161489][ T8825] IPVS: ftp: loaded support on port[0] = 21 [ 69.205518][ T8825] chnl_net:caif_netlink_parms(): no params data found [ 69.236507][ T8825] bridge0: port 1(bridge_slave_0) entered blocking state [ 69.247269][ T8825] bridge0: port 1(bridge_slave_0) entered disabled state [ 69.256839][ T8825] device bridge_slave_0 entered promiscuous mode [ 69.270394][ T8825] bridge0: port 2(bridge_slave_1) entered blocking state [ 69.277598][ T8825] bridge0: port 2(bridge_slave_1) entered disabled state [ 69.285217][ T8825] device bridge_slave_1 entered promiscuous mode [ 69.300224][ T8825] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 69.310714][ T8825] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link [ 69.329049][ T8825] team0: Port device team_slave_0 added [ 69.336367][ T8825] team0: Port device team_slave_1 added [ 69.349270][ T8825] batman_adv: batadv0: Adding interface: batadv_slave_0 [ 69.356393][ T8825] batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem. [ 69.382386][ T8825] batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active [ 69.394907][ T8825] batman_adv: batadv0: Adding interface: batadv_slave_1 [ 69.401976][ T8825] batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem. [ 69.428111][ T8825] batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active [ 69.505575][ T8825] device hsr_slave_0 entered promiscuous mode [ 69.543766][ T8825] device hsr_slave_1 entered promiscuous mode [ 69.633484][ T8825] netdevsim netdevsim0 netdevsim0: renamed from eth0 [ 69.676059][ T8825] netdevsim netdevsim0 netdevsim1: renamed from eth1 [ 69.715512][ T8825] netdevsim netdevsim0 netdevsim2: renamed from eth2 [ 69.765291][ T8825] netdevsim netdevsim0 netdevsim3: renamed from eth3 [ 69.855359][ T8825] bridge0: port 2(bridge_slave_1) entered blocking state [ 69.862661][ T8825] bridge0: port 2(bridge_slave_1) entered forwarding state [ 69.870512][ T8825] bridge0: port 1(bridge_slave_0) entered blocking state [ 69.877617][ T8825] bridge0: port 1(bridge_slave_0) entered forwarding state [ 69.911585][ T8825] 8021q: adding VLAN 0 to HW filter on device bond0 [ 69.924726][ T2680] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 69.936321][ T2680] bridge0: port 1(bridge_slave_0) entered disabled state [ 69.944785][ T2680] bridge0: port 2(bridge_slave_1) entered disabled state [ 69.952661][ T2680] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 69.964941][ T8825] 8021q: adding VLAN 0 to HW filter on device team0 [ 69.976233][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready [ 69.984585][ T2819] bridge0: port 1(bridge_slave_0) entered blocking state [ 69.991692][ T2819] bridge0: port 1(bridge_slave_0) entered forwarding state [ 70.002113][ T2680] IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_1: link becomes ready [ 70.011117][ T2680] bridge0: port 2(bridge_slave_1) entered blocking state [ 70.018180][ T2680] bridge0: port 2(bridge_slave_1) entered forwarding state [ 70.035918][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 70.045774][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 70.061014][ T8825] hsr0: Slave A (hsr_slave_0) is not up; please bring it up to get a fully working HSR network [ 70.071873][ T8825] hsr0: Slave B (hsr_slave_1) is not up; please bring it up to get a fully working HSR network [ 70.084659][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 70.092912][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready [ 70.102008][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready [ 70.110941][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready [ 70.130313][ T8825] 8021q: adding VLAN 0 to HW filter on device batadv0 [ 70.138366][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready [ 70.146402][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready [ 70.164780][ T2680] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_virt_wifi: link becomes ready [ 70.179636][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready [ 70.188787][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): vlan0: link becomes ready [ 70.196671][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): vlan1: link becomes ready [ 70.206958][ T8825] device veth0_vlan entered promiscuous mode [ 70.217451][ T8825] device veth1_vlan entered promiscuous mode [ 70.236202][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_macvtap: link becomes ready [ 70.246042][ T2819] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_macvtap: link becomes ready [ 70.257226][ T8825] device veth0_macvtap entered promiscuous mode [ 70.267209][ T8825] device veth1_macvtap entered promiscuous mode [ 70.282083][ T8825] batman_adv: batadv0: Interface activated: batadv_slave_0 [ 70.289968][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready [ 70.298961][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): macsec0: link becomes ready [ 70.307550][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready [ 70.316167][ T2719] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready [ 70.327061][ T8825] batman_adv: batadv0: Interface activated: batadv_slave_1 [ 70.335324][ T2680] IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready [ 70.344371][ T2680] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready executing program [ 70.493736][ C0] ================================================================== [ 70.501987][ C0] BUG: KASAN: use-after-free in find_match+0xb5/0xa10 [ 70.511377][ C0] Read of size 8 at addr ffff88808e59a320 by task kworker/0:2/2680 [ 70.520746][ C0] [ 70.523193][ C0] CPU: 0 PID: 2680 Comm: kworker/0:2 Not tainted 5.6.0-rc2-syzkaller #0 [ 70.531620][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 70.541979][ C0] Workqueue: ipv6_addrconf addrconf_dad_work [ 70.548489][ C0] Call Trace: [ 70.551759][ C0] [ 70.554658][ C0] dump_stack+0x1fb/0x318 [ 70.559048][ C0] print_address_description+0x74/0x5c0 [ 70.564581][ C0] ? vprintk_func+0x158/0x170 [ 70.569281][ C0] ? printk+0x62/0x8d [ 70.573406][ C0] ? vprintk_emit+0x2d4/0x3a0 [ 70.578168][ C0] __kasan_report+0x149/0x1c0 [ 70.582829][ C0] ? find_match+0xb5/0xa10 [ 70.587288][ C0] kasan_report+0x26/0x50 [ 70.591618][ C0] __asan_report_load8_noabort+0x14/0x20 [ 70.597242][ C0] find_match+0xb5/0xa10 [ 70.601481][ C0] __find_rr_leaf+0x1f6/0xb50 [ 70.606212][ C0] fib6_table_lookup+0x44f/0xb00 [ 70.611186][ C0] ip6_pol_route+0x187/0x1910 [ 70.615893][ C0] ? __flow_hash_from_keys+0x491/0x910 [ 70.621362][ C0] ip6_pol_route_input+0x54/0x80 [ 70.626358][ C0] ? ip6_route_input_lookup+0xd0/0xd0 [ 70.631723][ C0] fib6_rule_lookup+0x1e3/0x640 [ 70.636628][ C0] ip6_route_input+0x792/0xb20 [ 70.641397][ C0] ip6_rcv_finish_core+0x1f5/0x400 [ 70.646495][ C0] ? ipvlan_ns_exit+0xc0/0xc0 [ 70.651156][ C0] ip6_rcv_finish+0x138/0x260 [ 70.655827][ C0] ipv6_rcv+0xb0/0xe0 [ 70.659803][ C0] ? ip6_rcv_finish_core+0x400/0x400 [ 70.665163][ C0] __netif_receive_skb+0x136/0x370 [ 70.670453][ C0] process_backlog+0x4e8/0x980 [ 70.675307][ C0] net_rx_action+0x5ef/0x10c0 [ 70.679985][ C0] __do_softirq+0x283/0x7bd [ 70.684523][ C0] ? do_softirq_own_stack+0x2a/0x40 [ 70.689919][ C0] do_softirq_own_stack+0x2a/0x40 [ 70.694925][ C0] [ 70.697850][ C0] do_softirq+0xfd/0x190 [ 70.702379][ C0] ? local_bh_enable+0x9/0x30 [ 70.707050][ C0] __local_bh_enable_ip+0x194/0x240 [ 70.712415][ C0] local_bh_enable+0x1f/0x30 [ 70.717035][ C0] ip6_finish_output2+0x10ca/0x13e0 [ 70.722241][ C0] __ip6_finish_output+0x693/0x8c0 [ 70.727522][ C0] ip6_finish_output+0x52/0x1e0 [ 70.732362][ C0] ? ip6_output+0x2ad/0x3c0 [ 70.736901][ C0] ip6_output+0x2c2/0x3c0 [ 70.741219][ C0] ndisc_send_skb+0xa33/0xe20 [ 70.745937][ C0] ndisc_send_ns+0x5c6/0x7b0 [ 70.750604][ C0] addrconf_dad_work+0xaa7/0x1c20 [ 70.755667][ C0] process_one_work+0x7f5/0x10f0 [ 70.764658][ C0] worker_thread+0xbbc/0x1630 [ 70.769337][ C0] kthread+0x332/0x350 [ 70.773490][ C0] ? rcu_lock_release+0x30/0x30 [ 70.778333][ C0] ? kthread_blkcg+0xe0/0xe0 [ 70.782911][ C0] ret_from_fork+0x24/0x30 [ 70.787475][ C0] [ 70.789888][ C0] Allocated by task 8825: [ 70.794221][ C0] __kasan_kmalloc+0x118/0x1c0 [ 70.799021][ C0] kasan_kmalloc+0x9/0x10 [ 70.803344][ C0] __kmalloc_node+0x4d/0x60 [ 70.807844][ C0] kvmalloc_node+0x85/0x110 [ 70.812327][ C0] alloc_netdev_mqs+0x8e/0xd40 [ 70.817082][ C0] vti6_init_net+0x112/0x320 [ 70.821662][ C0] ops_init+0x355/0x430 [ 70.825807][ C0] setup_net+0x1eb/0x7f0 [ 70.830179][ C0] copy_net_ns+0x334/0x540 [ 70.834579][ C0] create_new_namespaces+0x4d7/0x9c0 [ 70.839890][ C0] unshare_nsproxy_namespaces+0x12a/0x190 [ 70.845589][ C0] ksys_unshare+0x478/0xa00 [ 70.850067][ C0] __x64_sys_unshare+0x38/0x40 [ 70.854915][ C0] do_syscall_64+0xf7/0x1c0 [ 70.859402][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 70.865271][ C0] [ 70.867581][ C0] Freed by task 8825: [ 70.871556][ C0] __kasan_slab_free+0x12e/0x1e0 [ 70.876473][ C0] kasan_slab_free+0xe/0x10 [ 70.880953][ C0] kfree+0x10d/0x220 [ 70.884823][ C0] netdev_name_node_alt_destroy+0x35c/0x380 [ 70.890692][ C0] rtnl_linkprop+0x42d/0x680 [ 70.895269][ C0] rtnl_dellinkprop+0x2a/0x40 [ 70.899945][ C0] rtnetlink_rcv_msg+0x889/0xd40 [ 70.904922][ C0] netlink_rcv_skb+0x19e/0x3e0 [ 70.909676][ C0] rtnetlink_rcv+0x1c/0x20 [ 70.914086][ C0] netlink_unicast+0x766/0x920 [ 70.918839][ C0] netlink_sendmsg+0xa2b/0xd40 [ 70.924712][ C0] ____sys_sendmsg+0x4f7/0x7f0 [ 70.929507][ C0] __sys_sendmsg+0x1ed/0x290 [ 70.934359][ C0] __x64_sys_sendmsg+0x7f/0x90 [ 70.939112][ C0] do_syscall_64+0xf7/0x1c0 [ 70.943598][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 70.949465][ C0] [ 70.951793][ C0] The buggy address belongs to the object at ffff88808e59a000 [ 70.951793][ C0] which belongs to the cache kmalloc-4k of size 4096 [ 70.965835][ C0] The buggy address is located 800 bytes inside of [ 70.965835][ C0] 4096-byte region [ffff88808e59a000, ffff88808e59b000) [ 70.979178][ C0] The buggy address belongs to the page: [ 70.984921][ C0] page:ffffea0002396680 refcount:1 mapcount:0 mapping:ffff8880aa402000 index:0x0 compound_mapcount: 0 [ 70.995878][ C0] flags: 0xfffe0000010200(slab|head) [ 71.001179][ C0] raw: 00fffe0000010200 ffffea0002773908 ffffea0002895408 ffff8880aa402000 [ 71.009744][ C0] raw: 0000000000000000 ffff88808e59a000 0000000100000001 0000000000000000 [ 71.018364][ C0] page dumped because: kasan: bad access detected [ 71.024876][ C0] [ 71.027249][ C0] Memory state around the buggy address: [ 71.032861][ C0] ffff88808e59a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.041012][ C0] ffff88808e59a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.049094][ C0] >ffff88808e59a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.057197][ C0] ^ [ 71.062293][ C0] ffff88808e59a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.070453][ C0] ffff88808e59a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.078623][ C0] ================================================================== [ 71.086665][ C0] Disabling lock debugging due to kernel taint [ 71.092871][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 71.099452][ C0] CPU: 0 PID: 2680 Comm: kworker/0:2 Tainted: G B 5.6.0-rc2-syzkaller #0 [ 71.109143][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 71.125055][ C0] Workqueue: ipv6_addrconf addrconf_dad_work [ 71.131018][ C0] Call Trace: [ 71.134325][ C0] [ 71.137163][ C0] dump_stack+0x1fb/0x318 [ 71.141573][ C0] panic+0x264/0x7a9 [ 71.145447][ C0] ? trace_hardirqs_on+0x34/0x80 [ 71.150417][ C0] ? __kasan_report+0x193/0x1c0 [ 71.155293][ C0] ? trace_hardirqs_on+0x34/0x80 [ 71.160227][ C0] __kasan_report+0x1b9/0x1c0 [ 71.164896][ C0] ? find_match+0xb5/0xa10 [ 71.169311][ C0] kasan_report+0x26/0x50 [ 71.173754][ C0] __asan_report_load8_noabort+0x14/0x20 [ 71.179403][ C0] find_match+0xb5/0xa10 [ 71.183787][ C0] __find_rr_leaf+0x1f6/0xb50 [ 71.188457][ C0] fib6_table_lookup+0x44f/0xb00 [ 71.193393][ C0] ip6_pol_route+0x187/0x1910 [ 71.198066][ C0] ? __flow_hash_from_keys+0x491/0x910 [ 71.203512][ C0] ip6_pol_route_input+0x54/0x80 [ 71.208439][ C0] ? ip6_route_input_lookup+0xd0/0xd0 [ 71.213896][ C0] fib6_rule_lookup+0x1e3/0x640 [ 71.218746][ C0] ip6_route_input+0x792/0xb20 [ 71.223673][ C0] ip6_rcv_finish_core+0x1f5/0x400 [ 71.228763][ C0] ? ipvlan_ns_exit+0xc0/0xc0 [ 71.233436][ C0] ip6_rcv_finish+0x138/0x260 [ 71.238201][ C0] ipv6_rcv+0xb0/0xe0 [ 71.242205][ C0] ? ip6_rcv_finish_core+0x400/0x400 [ 71.247524][ C0] __netif_receive_skb+0x136/0x370 [ 71.252657][ C0] process_backlog+0x4e8/0x980 [ 71.257460][ C0] net_rx_action+0x5ef/0x10c0 [ 71.262295][ C0] __do_softirq+0x283/0x7bd [ 71.266787][ C0] ? do_softirq_own_stack+0x2a/0x40 [ 71.271976][ C0] do_softirq_own_stack+0x2a/0x40 [ 71.276973][ C0] [ 71.279937][ C0] do_softirq+0xfd/0x190 [ 71.284266][ C0] ? local_bh_enable+0x9/0x30 [ 71.289391][ C0] __local_bh_enable_ip+0x194/0x240 [ 71.294575][ C0] local_bh_enable+0x1f/0x30 [ 71.299147][ C0] ip6_finish_output2+0x10ca/0x13e0 [ 71.304340][ C0] __ip6_finish_output+0x693/0x8c0 [ 71.309430][ C0] ip6_finish_output+0x52/0x1e0 [ 71.314255][ C0] ? ip6_output+0x2ad/0x3c0 [ 71.318734][ C0] ip6_output+0x2c2/0x3c0 [ 71.323099][ C0] ndisc_send_skb+0xa33/0xe20 [ 71.327775][ C0] ndisc_send_ns+0x5c6/0x7b0 [ 71.332347][ C0] addrconf_dad_work+0xaa7/0x1c20 [ 71.337367][ C0] process_one_work+0x7f5/0x10f0 [ 71.342348][ C0] worker_thread+0xbbc/0x1630 [ 71.347051][ C0] kthread+0x332/0x350 [ 71.351094][ C0] ? rcu_lock_release+0x30/0x30 [ 71.355919][ C0] ? kthread_blkcg+0xe0/0xe0 [ 71.360499][ C0] ret_from_fork+0x24/0x30 [ 71.366179][ C0] Kernel Offset: disabled [ 71.370499][ C0] Rebooting in 86400 seconds..