INIT: Entering runlevel: 2

[info] Using makefile-style concurrent boot in runlevel 2.
[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c.
[....] 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

Warning: Permanently added 'ci-upstream-kasan-gce-386-2,10.128.15.192' (ECDSA) to the list of known hosts.
2017/10/01 22:20:13 parsed 1 programs
2017/10/01 22:20:13 executed programs: 0
syzkaller login: [   40.020994] refcount_t: underflow; use-after-free.
[   40.024327] ------------[ cut here ]------------
[   40.025438] WARNING: CPU: 1 PID: 3482 at lib/refcount.c:186 refcount_sub_and_test+0x167/0x1b0
[   40.029092] Kernel panic - not syncing: panic_on_warn set ...
[   40.029092] 
[   40.030110] CPU: 1 PID: 3482 Comm: syz-executor6 Not tainted 4.14.0-rc2+ #21
[   40.031086] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   40.032328] Call Trace:
[   40.032707]  dump_stack+0x194/0x257
[   40.033204]  ? arch_local_irq_restore+0x53/0x53
[   40.033864]  panic+0x1e4/0x417
[   40.034304]  ? __warn+0x1d9/0x1d9
[   40.034808]  ? show_regs_print_info+0x65/0x65
[   40.035446]  ? refcount_sub_and_test+0x167/0x1b0
[   40.036104]  __warn+0x1c4/0x1d9
[   40.036556]  ? refcount_sub_and_test+0x167/0x1b0
[   40.037199]  report_bug+0x211/0x2d0
[   40.037713]  fixup_bug+0x40/0x90
[   40.038176]  do_trap+0x260/0x390
[   40.038646]  do_error_trap+0x120/0x390
[   40.039177]  ? do_trap+0x390/0x390
[   40.039673]  ? refcount_sub_and_test+0x167/0x1b0
[   40.040311]  ? vprintk_emit+0x3ea/0x590
[   40.041062]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   40.045401]  do_invalid_op+0x1b/0x20
[   40.049092]  invalid_op+0x18/0x20
[   40.052521] RIP: 0010:refcount_sub_and_test+0x167/0x1b0
[   40.057857] RSP: 0018:ffff8801cbae6370 EFLAGS: 00010282
[   40.063286] RAX: 0000000000000026 RBX: 0000000000000001 RCX: 0000000000000000
[   40.071754] RDX: 0000000000000026 RSI: 1ffff1003975cc2e RDI: ffffed003975cc62
[   40.078998] RBP: ffff8801cbae6400 R08: ffff8801cbae5a60 R09: 0000000000000000
[   40.086240] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1003975cc6f
[   40.093487] R13: 00000000ffffff01 R14: 0000000000000100 R15: ffff8801cb8f15e4
[   40.100754]  ? refcount_inc+0x50/0x50
[   40.104528]  ? __sctp_outq_teardown+0xc7d/0x15a0
[   40.109275]  ? sctp_association_free+0x2d0/0x930
[   40.114003]  ? sctp_do_sm+0x28e7/0x6dd0
[   40.117947]  ? sctp_primitive_SHUTDOWN+0xa0/0xd0
[   40.122673]  ? sctp_close+0x3c6/0x980
[   40.126445]  ? inet_release+0xed/0x1c0
[   40.130327]  sctp_wfree+0x183/0x620
[   40.133939]  ? __sctp_write_space+0x910/0x910
[   40.138414]  skb_release_head_state+0x124/0x200
[   40.143068]  skb_release_all+0x15/0x60
[   40.146931]  consume_skb+0x153/0x490
[   40.150619]  ? sctp_chunk_put+0x99/0x420
[   40.154652]  ? alloc_skb_with_frags+0x710/0x710
[   40.159292]  ? sctp_chunk_hold+0x20/0x20
[   40.163330]  ? refcount_sub_and_test+0x115/0x1b0
[   40.168061]  ? refcount_inc+0x50/0x50
[   40.171863]  ? mark_held_locks+0xb2/0x100
[   40.175990]  ? sctp_datamsg_put+0x456/0x560
[   40.180310]  sctp_chunk_put+0x29c/0x420
[   40.184260]  ? sctp_chunk_hold+0x20/0x20
[   40.188299]  ? sctp_transport_dst_confirm+0x50/0x50
[   40.193295]  ? debug_check_no_locks_freed+0x3d0/0x3d0
[   40.198480]  sctp_chunk_free+0x53/0x60
[   40.202344]  __sctp_outq_teardown+0xc7d/0x15a0
[   40.206901]  ? inet6_release+0x50/0x70
[   40.210768]  ? sctp_inq_set_th_handler+0x1b0/0x1b0
[   40.215678]  ? unwind_next_frame.part.6+0x1ae/0xc70
[   40.220679]  ? unwind_next_frame.part.6+0x1ae/0xc70
[   40.225667]  ? unwind_dump+0x4c0/0x4c0
[   40.229526]  ? unwind_next_frame.part.6+0x1ae/0xc70
[   40.234516]  ? unwind_dump+0x4c0/0x4c0
[   40.238379]  ? print_usage_bug+0x480/0x480
[   40.242600]  ? check_noncircular+0x20/0x20
[   40.246808]  ? check_noncircular+0x20/0x20
[   40.251016]  ? unwind_get_return_address+0x61/0xa0
[   40.255922]  ? __save_stack_trace+0x61/0xd0
[   40.260226]  ? check_noncircular+0x20/0x20
[   40.264435]  ? print_usage_bug+0x480/0x480
[   40.268658]  ? find_held_lock+0x39/0x1d0
[   40.272702]  ? lock_downgrade+0x990/0x990
[   40.276830]  ? sk_dst_check+0x560/0x560
[   40.280781]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   40.285773]  ? lock_release+0xd70/0xd70
[   40.289729]  sctp_outq_free+0x15/0x20
[   40.293505]  sctp_association_free+0x2d0/0x930
[   40.298069]  ? sctp_asconf_queue_teardown+0x700/0x700
[   40.303236]  ? sock_def_wakeup+0x222/0x350
[   40.307445]  ? sk_dst_check+0x560/0x560
[   40.311392]  ? sctp_association_put+0x74/0x2f0
[   40.315947]  ? sctp_association_hold+0x20/0x20
[   40.320528]  ? unwind_dump+0x4c0/0x4c0
[   40.324404]  sctp_do_sm+0x28e7/0x6dd0
[   40.328180]  ? __kernel_text_address+0xd/0x40
[   40.332662]  ? sctp_do_8_2_transport_strike.isra.16+0x8a0/0x8a0
[   40.338696]  ? print_usage_bug+0x480/0x480
[   40.342905]  ? __lock_acquire+0x20fd/0x4620
[   40.347202]  ? print_usage_bug+0x480/0x480
[   40.351420]  ? find_held_lock+0x39/0x1d0
[   40.355465]  ? lock_downgrade+0x990/0x990
[   40.359600]  ? skb_dequeue+0x22/0x180
[   40.363383]  ? do_raw_spin_trylock+0x190/0x190
[   40.367942]  ? mark_held_locks+0xb2/0x100
[   40.372069]  ? trace_hardirqs_on+0xd/0x10
[   40.376206]  sctp_primitive_SHUTDOWN+0xa0/0xd0
[   40.380796]  sctp_close+0x3c6/0x980
[   40.384416]  ? sctp_apply_peer_addr_params+0xf30/0xf30
[   40.389675]  ? unwind_get_return_address+0x61/0xa0
[   40.394589]  ? check_noncircular+0x20/0x20
[   40.398828]  ? depot_save_stack+0x12c/0x490
[   40.403145]  ? ipv6_sock_ac_close+0x2e8/0x3e0
[   40.407637]  ? ipv6_sock_mc_close+0x148/0x1a0
[   40.412123]  ? ip_mc_drop_socket+0x1ce/0x230
[   40.416517]  ? __fsnotify_parent+0xb4/0x3a0
[   40.420829]  inet_release+0xed/0x1c0
[   40.424539]  inet6_release+0x50/0x70
[   40.428272]  sock_release+0x8d/0x1e0
[   40.431965]  ? sock_release+0x1e0/0x1e0
[   40.435915]  sock_close+0x16/0x20
[   40.439344]  __fput+0x333/0x7f0
[   40.442607]  ? fput+0x140/0x140
[   40.445867]  ? _raw_spin_unlock_irq+0x27/0x70
[   40.450346]  ____fput+0x15/0x20
[   40.453602]  task_work_run+0x199/0x270
[   40.457467]  ? task_work_cancel+0x210/0x210
[   40.461768]  ? _raw_spin_unlock+0x22/0x30
[   40.465893]  ? switch_task_namespaces+0x87/0xc0
[   40.470540]  do_exit+0x9d2/0x1af0
[   40.473987]  ? mm_update_next_owner+0x930/0x930
[   40.478637]  ? lock_downgrade+0x990/0x990
[   40.482772]  ? refill_pi_state_cache.part.6+0x2f0/0x2f0
[   40.488118]  ? futex_wait+0x3ad/0x990
[   40.491901]  ? do_raw_spin_trylock+0x190/0x190
[   40.496459]  ? fault_in_user_writeable+0x90/0x90
[   40.501194]  ? futex_wake+0x680/0x680
[   40.504977]  ? check_noncircular+0x20/0x20
[   40.509216]  ? drop_futex_key_refs.isra.13+0x63/0xb0
[   40.514303]  ? futex_wait+0x69e/0x990
[   40.518087]  ? futex_wait_setup+0x3d0/0x3d0
[   40.522402]  ? find_held_lock+0x39/0x1d0
[   40.526452]  ? lock_downgrade+0x990/0x990
[   40.530577]  ? recalc_sigpending_tsk+0x117/0x150
[   40.535311]  ? recalc_sigpending+0x103/0x160
[   40.539729]  ? recalc_sigpending_tsk+0x150/0x150
[   40.544465]  ? get_signal+0x2b2/0x16d0
[   40.548338]  do_group_exit+0x149/0x400
[   40.552198]  ? __lock_is_held+0xbc/0x140
[   40.556234]  ? SyS_exit+0x30/0x30
[   40.559674]  ? _raw_spin_unlock_irq+0x27/0x70
[   40.564163]  ? trace_hardirqs_on_caller+0x421/0x5c0
[   40.569180]  get_signal+0x73f/0x16d0
[   40.572879]  ? ptrace_notify+0x130/0x130
[   40.576923]  ? __fd_install+0x2f7/0x6a0
[   40.580869]  ? trace_hardirqs_on_thunk+0x1a/0x1c
[   40.585603]  ? get_unused_fd_flags+0x190/0x190
[   40.590172]  do_signal+0x94/0x1ee0
[   40.593687]  ? copy_user_generic_unrolled+0x89/0xc0
[   40.598708]  ? _copy_to_user+0xa2/0xc0
[   40.602587]  ? setup_sigcontext+0x7d0/0x7d0
[   40.606895]  ? fput+0xd2/0x140
[   40.610075]  ? SYSC_accept4+0x4f2/0x850
[   40.614058]  ? kernel_accept+0x2f0/0x2f0
[   40.618133]  ? exit_to_usermode_loop+0x8c/0x310
[   40.622793]  exit_to_usermode_loop+0x214/0x310
[   40.627354]  ? trace_event_raw_event_sys_exit+0x260/0x260
[   40.632866]  ? lock_acquire+0x1d5/0x580
[   40.636817]  ? do_fast_syscall_32+0x158/0xf05
[   40.641295]  do_fast_syscall_32+0x83e/0xf05
[   40.645594]  ? compat_start_thread+0x80/0x80
[   40.649986]  ? do_int80_syscall_32+0x940/0x940
[   40.654551]  ? lockdep_sys_exit+0x47/0xf0
[   40.658676]  ? syscall_return_slowpath+0x2b3/0x510
[   40.663581]  ? finish_task_switch+0x1aa/0x740
[   40.668068]  ? prepare_exit_to_usermode+0x2d0/0x2d0
[   40.673069]  ? sysret32_from_system_call+0x5/0x3b
[   40.677891]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[   40.682716]  entry_SYSENTER_compat+0x51/0x60
[   40.687105] RIP: 0023:0xf7f14c79
[   40.690458] RSP: 002b:00000000f7ece12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0
[   40.698156] RAX: fffffffffffffe00 RBX: 00000000081280f8 RCX: 0000000000000000
[   40.705410] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[   40.712667] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[   40.719912] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[   40.727159] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[   40.735030] Dumping ftrace buffer:
[   40.738597]    (ftrace buffer empty)
[   40.742278] Kernel Offset: disabled
[   40.745882] Rebooting in 86400 seconds..