[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.784885] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 21.634369] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 21.894689] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 22.879495] random: sshd: uninitialized urandom read (32 bytes read, 82 bits of entropy available) [ 23.039493] random: sshd: uninitialized urandom read (32 bytes read, 86 bits of entropy available) Warning: Permanently added '10.128.0.13' (ECDSA) to the list of known hosts. [ 28.562786] random: sshd: uninitialized urandom read (32 bytes read, 92 bits of entropy available) net.ipv6.conf.syz_tun.accept_dad = 0 [ 28.658759] IPVS: Creating netns size=2552 id=1 net.ipv6.conf.syz_tun.router_solicitations = 0 RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported Error: argument "bridge0" is wrong: Device does not exist Error: argument "bridge0" is wrong: Device does not exist [ 28.913065] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 28.928184] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready Error: argument "bond0" is wrong: Device does not exist Error: argument "bond0" is wrong: Device does not exist [ 29.015628] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bond: link is not ready [ 29.031394] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bond: link is not ready Error: argument "team0" is wrong: Device does not exist Error: argument "team0" is wrong: Device does not exist [ 29.121443] IPv6: ADDRCONF(NETDEV_UP): veth0_to_team: link is not ready [ 29.137204] IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready [ 29.155336] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 29.173536] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready RTNETLINK answers: Operation not supported Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" RTNETLINK answers: Operation not supported Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "team0" [ 29.925663] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 29.965601] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" [ 30.281929] ================================================================== [ 30.289338] BUG: KASAN: slab-out-of-bounds in ip6_tnl_xmit2+0x2043/0x20d0 [ 30.296241] Read of size 16 at addr ffff8801d8c9e6b0 by task syz-executor247/3706 [ 30.303828] [ 30.305444] CPU: 0 PID: 3706 Comm: syz-executor247 Not tainted 4.4.129-g23eaecc #27 [ 30.313217] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.322548] 0000000000000000 5725feeea7834f35 ffff8801ce697000 ffffffff81e0dc8d executing program executing program [ 30.330537] ffffea0007632700 ffff8801d8c9e6b0 0000000000000000 ffff8801d8c9e6b8 [ 30.338529] ffff8801cdebc400 ffff8801ce697038 ffffffff8151535c ffff8801d8c9e6b0 [ 30.346531] Call Trace: [ 30.349102] [] dump_stack+0xc1/0x124 [ 30.354441] [] print_address_description+0x6c/0x216 [ 30.361079] [] kasan_report.cold.7+0x175/0x2f7 [ 30.367286] [] ? ip6_tnl_xmit2+0x2043/0x20d0 [ 30.373322] [] __asan_report_load_n_noabort+0xf/0x20 [ 30.380046] [] ip6_tnl_xmit2+0x2043/0x20d0 [ 30.385904] [] ? __lock_acquire+0xa86/0x5270 [ 30.391937] [] ? sock_sendmsg+0xcc/0x110 [ 30.397619] [] ? ip6ip6_err+0x530/0x530 [ 30.403225] [] ? debug_check_no_locks_freed+0x210/0x210 [ 30.410211] [] ? debug_check_no_locks_freed+0x210/0x210 [ 30.417201] [] ? debug_check_no_locks_freed+0x210/0x210 [ 30.424186] [] ? make_kuid+0xf0/0x180 [ 30.429611] [] ip6_tnl_xmit+0x910/0xc60 [ 30.435207] [] ? ip6_tnl_xmit2+0x20d0/0x20d0 [ 30.441247] [] dev_hard_start_xmit+0x7b1/0x11c0 [ 30.447537] [] ? dev_hard_start_xmit+0xa8/0x11c0 [ 30.453918] [] __dev_queue_xmit+0x16c0/0x1c80 [ 30.460035] [] ? __dev_queue_xmit+0x1d7/0x1c80 [ 30.466240] [] ? debug_check_no_locks_freed+0x210/0x210 [ 30.473224] [] ? netdev_pick_tx+0x2c0/0x2c0 [ 30.479178] [] ? selinux_ip_postroute+0x4a1/0xab0 [ 30.485644] [] ? _raw_spin_unlock_irqrestore+0x5a/0x70 [ 30.492559] [] ? selinux_ip_postroute_compat+0x390/0x390 [ 30.499631] [] ? ctnetlink_expect_event+0x770/0x770 [ 30.506270] [] ? check_preemption_disabled+0x3b/0x170 [ 30.513084] [] dev_queue_xmit+0x17/0x20 [ 30.518680] [] neigh_direct_output+0x15/0x20 [ 30.524722] [] ip_finish_output2+0x6ab/0x1110 [ 30.530848] [] ? ip_finish_output2+0x212/0x1110 [ 30.537141] [] ? nf_ct_deliver_cached_events+0x335/0x560 [ 30.544214] [] ? ip_copy_metadata+0x700/0x700 [ 30.550345] [] ip_do_fragment+0x198b/0x2150 [ 30.556312] [] ? ip_copy_metadata+0x700/0x700 [ 30.562430] [] ip_fragment.constprop.50+0x143/0x200 [ 30.569070] [] ip_finish_output+0x6c4/0xbc0 [ 30.575016] [] ip_mc_output+0x233/0x980 [ 30.580611] [] ? ip_queue_xmit+0x1ab0/0x1ab0 [ 30.586642] [] ? ip_make_skb+0x116/0x210 [ 30.592335] [] ? ip_fragment.constprop.50+0x200/0x200 [ 30.599150] [] ? ip_flush_pending_frames+0x30/0x30 [ 30.605714] [] ip_local_out+0x9b/0x180 [ 30.611232] [] ip_send_skb+0x3c/0xc0 [ 30.616569] [] udp_send_skb+0x5c3/0xc60 [ 30.622166] [] udp_sendmsg+0x16ce/0x1bb0 [ 30.627849] [] ? ip_reply_glue_bits+0xc0/0xc0 [ 30.633964] [] ? udp4_lib_lookup+0x60/0x60 [ 30.639820] [] ? ip4_datagram_connect+0x50/0x50 [ 30.646113] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 30.652405] [] ? __local_bh_enable_ip+0x6a/0xd0 [ 30.658698] [] ? _raw_spin_unlock_bh+0x30/0x40 [ 30.664913] [] ? release_sock+0x3b6/0x500 [ 30.670685] [] ? udp_v4_get_port+0x139/0x180 [ 30.676720] [] inet_sendmsg+0x203/0x4d0 [ 30.682330] [] ? inet_sendmsg+0x73/0x4d0 [ 30.688025] [] ? inet_recvmsg+0x4c0/0x4c0 [ 30.693805] [] sock_sendmsg+0xcc/0x110 [ 30.699327] [] SYSC_sendto+0x21c/0x370 [ 30.704835] [] ? SYSC_connect+0x300/0x300 [ 30.710607] [] ? sock_has_perm+0x29f/0x400 [ 30.716472] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 30.723546] [] ? selinux_netlbl_socket_setsockopt+0x97/0x340 [ 30.730968] [] ? selinux_netlbl_sock_rcv_skb+0x400/0x400 [ 30.738052] [] ? sock_common_setsockopt+0x9a/0xe0 [ 30.744524] [] ? SyS_setsockopt+0x185/0x260 [ 30.750475] [] ? SyS_recv+0x40/0x40 [ 30.755727] [] ? security_file_ioctl+0x8f/0xc0 [ 30.761931] [] SyS_sendto+0x40/0x50 [ 30.767185] [] entry_SYSCALL_64_fastpath+0x22/0x9e [ 30.773741] [ 30.775348] Allocated by task 3706: [ 30.778945] [] save_stack_trace+0x26/0x50 [ 30.784840] [] save_stack+0x43/0xd0 [ 30.790236] [] kasan_kmalloc+0xc7/0xe0 [ 30.795864] [] __kmalloc+0x124/0x310 [ 30.801321] [] __neigh_create+0x1d6/0x1b20 [ 30.807299] [] ipv4_neigh_lookup+0x4dd/0x700 [ 30.813458] [] ip6_tnl_xmit2+0x613/0x20d0 [ 30.819367] [] ip6_tnl_xmit+0x910/0xc60 [ 30.825080] [] dev_hard_start_xmit+0x7b1/0x11c0 [ 30.831497] [] __dev_queue_xmit+0x16c0/0x1c80 [ 30.838407] [] dev_queue_xmit+0x17/0x20 [ 30.844128] [] neigh_direct_output+0x15/0x20 [ 30.850278] [] ip_finish_output2+0x6ab/0x1110 [ 30.856519] [] ip_do_fragment+0x198b/0x2150 [ 30.862584] [] ip_fragment.constprop.50+0x143/0x200 [ 30.869339] [] ip_finish_output+0x6c4/0xbc0 [ 30.875402] [] ip_mc_output+0x233/0x980 [ 30.881114] [] ip_local_out+0x9b/0x180 [ 30.886743] [] ip_send_skb+0x3c/0xc0 [ 30.892246] [] udp_send_skb+0x5c3/0xc60 [ 30.897965] [] udp_sendmsg+0x16ce/0x1bb0 [ 30.903766] [] inet_sendmsg+0x203/0x4d0 [ 30.909486] [] sock_sendmsg+0xcc/0x110 [ 30.915115] [] SYSC_sendto+0x21c/0x370 [ 30.920752] [] SyS_sendto+0x40/0x50 [ 30.926120] [] entry_SYSCALL_64_fastpath+0x22/0x9e [ 30.932790] [ 30.934391] Freed by task 2371: [ 30.937641] [] save_stack_trace+0x26/0x50 [ 30.943532] [] save_stack+0x43/0xd0 [ 30.948910] [] kasan_slab_free+0x72/0xc0 [ 30.954711] [] kfree+0xf4/0x310 [ 30.959731] [] free_pipe_info+0x210/0x2c0 [ 30.965630] [] put_pipe_info+0xb8/0xe0 [ 30.971280] [] pipe_release+0x1af/0x250 [ 30.976991] [] __fput+0x235/0x6f0 [ 30.982186] [] ____fput+0x15/0x20 [ 30.987384] [] task_work_run+0x10f/0x190 [ 30.993186] [] exit_to_usermode_loop+0x13d/0x160 [ 30.999693] [] syscall_return_slowpath+0x1b5/0x1f0 [ 31.006362] [] int_ret_from_sys_call+0x25/0xa3 [ 31.012685] [ 31.014287] The buggy address belongs to the object at ffff8801d8c9e400 [ 31.014287] which belongs to the cache kmalloc-1024 of size 1024 [ 31.027091] The buggy address is located 688 bytes inside of [ 31.027091] 1024-byte region [ffff8801d8c9e400, ffff8801d8c9e800) [ 31.039024] The buggy address belongs to the page: [ 31.274664] kasan: CONFIG_KASAN_INLINE enabled [ 31.279145] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN [ 31.292149] Dumping ftrace buffer: [ 31.295684] (ftrace buffer empty) [ 31.299397] Modules linked in: [ 31.302725] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.129-g23eaecc #27 [ 31.309734] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.319095] task: ffff8801d9a41800 task.stack: ffff8801d9a50000 [ 31.325158] RIP: 0010:[] [] debug_object_activate+0x1b7/0x480 [ 31.334428] RSP: 0018:ffff8801db307bb0 EFLAGS: 00010802 [ 31.339879] RAX: dffffc0000000000 RBX: 8000000000004080 RCX: ffffffff85a3b128 [ 31.347159] RDX: 1000000000000813 RSI: ffff8801d9a42108 RDI: 8000000000004098 [ 31.354439] RBP: ffff8801db307c68 R08: 0000000000000096 R09: 0000000000000001 [ 31.361713] R10: 0000000000000001 R11: ffff8801d9a41800 R12: 1ffff1003b660f78 [ 31.368999] R13: ffff8800bafc0f78 R14: 0000000000000004 R15: ffffffff8448fc40 [ 31.376283] FS: 0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 [ 31.384519] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 31.390408] CR2: 00007fa50d0771b0 CR3: 00000001d1916000 CR4: 00000000001606f0 [ 31.397690] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 31.404976] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 31.412253] Stack: [ 31.414405] ffff8801d9a41800 ffffffff85a3b128 0000000041b58ab3 ffffffff84208c0f [ 31.422493] ffffffff81e6f190 ffff8801d9a420d8 0000000000000000 0000000000000000 [ 31.430569] 0000000000000005 ffff8800bafc0f78 ffffffff8448fc40 ffffffff85390520 [ 31.438629] Call Trace: [ 31.441205] [ 31.443303] [] ? debug_object_init_on_stack+0x20/0x20 [ 31.450459] [] __queue_work+0x48/0xea0 [ 31.456015] [] ? __lock_is_held+0xa2/0xf0 [ 31.461831] [] delayed_work_timer_fn+0x68/0x90 [ 31.468076] [] ? rcu_read_lock_sched_held+0x103/0x120 [ 31.474930] [] call_timer_fn+0x18c/0x870 [ 31.480658] [] ? call_timer_fn+0xda/0x870 [ 31.486480] [] ? debug_object_deactivate+0x214/0x340 [ 31.493256] [] ? __queue_work+0xea0/0xea0 [ 31.499181] [] ? process_timeout+0x20/0x20 [ 31.505085] [] ? run_timer_softirq+0x507/0xb90 [ 31.511339] [] run_timer_softirq+0x51d/0xb90 [ 31.517418] [] ? __queue_work+0xea0/0xea0 [ 31.523233] [] ? call_timer_fn+0x870/0x870 [ 31.529145] [] __do_softirq+0x22c/0xa1a [ 31.534791] [] irq_exit+0x10d/0x140 [ 31.540083] [] smp_apic_timer_interrupt+0x81/0xa0 [ 31.546598] [] apic_timer_interrupt+0xa0/0xb0 [ 31.552743] [ 31.554832] [] ? native_safe_halt+0x6/0x10 [ 31.561045] [] default_idle+0x55/0x3c0 [ 31.566602] [] arch_cpu_idle+0x10/0x20 [ 31.572156] [] default_idle_call+0x57/0x70 [ 31.578061] [] cpu_startup_entry+0x6af/0x780 [ 31.584136] [] ? call_cpuidle+0xe0/0xe0 [ 31.589777] [] start_secondary+0x324/0x400 [ 31.595794] [] ? set_cpu_sibling_map+0x1180/0x1180 [ 31.602812] Code: 8c 02 00 00 48 8b 1b 41 be 01 00 00 00 48 85 db 74 46 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 18 41 83 c6 01 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e6 01 00 00 4c 3b 6b 18 0f 84 9e 00 00 00 48 [ 31.630617] RIP [] debug_object_activate+0x1b7/0x480 [ 31.637556] RSP [ 31.641180] ---[ end trace cdcd355bd3db684a ]--- [ 31.645932] Kernel panic - not syncing: Fatal exception in interrupt [ 32.785001] PANIC: double fault, error_code: 0x0