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-next-kasan-gce-7,10.128.0.16' (ECDSA) to the list of known hosts. 2017/10/24 03:08:00 parsed 1 programs 2017/10/24 03:08:00 executed programs: 0 syzkaller login: [ 45.014533] refcount_t: underflow; use-after-free. [ 45.015357] ------------[ cut here ]------------ [ 45.016915] WARNING: CPU: 1 PID: 3533 at lib/refcount.c:186 refcount_sub_and_test+0x167/0x1b0 [ 45.019273] Kernel panic - not syncing: panic_on_warn set ... [ 45.019273] [ 45.020286] CPU: 0 PID: 3533 Comm: syz-executor3 Not tainted 4.14.0-rc5-next-20171018+ #36 [ 45.021395] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.022623] Call Trace: [ 45.022982] dump_stack+0x194/0x257 [ 45.023473] ? arch_local_irq_restore+0x53/0x53 [ 45.024103] ? vsnprintf+0x1ed/0x1900 [ 45.024620] panic+0x1e4/0x41c [ 45.025053] ? refcount_error_report+0x214/0x214 [ 45.025719] ? show_regs_print_info+0x65/0x65 [ 45.026348] ? __warn+0x1a9/0x1e0 [ 45.026999] ? refcount_sub_and_test+0x167/0x1b0 [ 45.027643] __warn+0x1c4/0x1e0 [ 45.028087] ? refcount_sub_and_test+0x167/0x1b0 [ 45.028724] report_bug+0x211/0x2d0 [ 45.029234] fixup_bug+0x40/0x90 [ 45.029691] do_trap+0x260/0x390 [ 45.030152] do_error_trap+0x120/0x390 [ 45.030678] ? do_trap+0x390/0x390 [ 45.031156] ? refcount_sub_and_test+0x167/0x1b0 [ 45.031789] ? vprintk_emit+0x3ea/0x590 [ 45.032330] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 45.033003] do_invalid_op+0x1b/0x20 [ 45.033504] invalid_op+0x18/0x20 [ 45.034013] RIP: 0010:refcount_sub_and_test+0x167/0x1b0 [ 45.034720] RSP: 0018:ffff8801cfe86500 EFLAGS: 00010282 [ 45.040051] RAX: 0000000000000026 RBX: 0000000000000001 RCX: 0000000000000000 [ 45.047286] RDX: 0000000000000026 RSI: 1ffff10039fd0c60 RDI: ffffed0039fd0c94 [ 45.054521] RBP: ffff8801cfe86590 R08: 0000000000000001 R09: 0000000000000000 [ 45.061757] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10039fd0ca1 [ 45.068994] R13: 00000000ffffff01 R14: 0000000000000100 R15: ffff8801cf9a89bc [ 45.076254] ? refcount_inc+0x50/0x50 [ 45.080022] ? sctp_outq_free+0x15/0x20 [ 45.083966] ? sctp_do_sm+0x271b/0x6a30 [ 45.087907] ? sctp_primitive_SHUTDOWN+0xa0/0xd0 [ 45.092629] ? sctp_close+0x3c6/0x980 [ 45.096419] ? inet_release+0xed/0x1c0 [ 45.100276] ? sock_release+0x8d/0x1e0 [ 45.104140] sctp_wfree+0x183/0x620 [ 45.107735] ? __sctp_write_space+0x910/0x910 [ 45.112201] skb_release_head_state+0x124/0x200 [ 45.116839] skb_release_all+0x15/0x60 [ 45.120696] consume_skb+0x153/0x490 [ 45.124377] ? sctp_chunk_put+0x99/0x420 [ 45.128404] ? alloc_skb_with_frags+0x750/0x750 [ 45.133038] ? sctp_chunk_hold+0x20/0x20 [ 45.137068] ? refcount_sub_and_test+0x115/0x1b0 [ 45.141791] ? refcount_inc+0x50/0x50 [ 45.145555] ? mark_held_locks+0xaf/0x100 [ 45.149669] ? sctp_datamsg_put+0x456/0x560 [ 45.153962] sctp_chunk_put+0x29c/0x420 [ 45.157904] ? sctp_chunk_hold+0x20/0x20 [ 45.161934] ? sctp_transport_dst_confirm+0x50/0x50 [ 45.166919] ? sctp_sched_fcfs_dequeue+0x198/0x290 [ 45.171816] ? sctp_sched_dequeue_common+0x5d0/0x5d0 [ 45.176883] ? print_irqtrace_events+0x270/0x270 [ 45.181604] ? print_irqtrace_events+0x270/0x270 [ 45.186327] sctp_chunk_free+0x53/0x60 [ 45.190183] __sctp_outq_teardown+0xa5b/0x1230 [ 45.194739] ? sctp_inq_set_th_handler+0x1b0/0x1b0 [ 45.199634] ? print_irqtrace_events+0x270/0x270 [ 45.204355] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 45.209518] ? __lock_acquire+0x6aa/0x3d50 [ 45.213727] ? check_noncircular+0x20/0x20 [ 45.217931] ? print_irqtrace_events+0x270/0x270 [ 45.222652] ? __lock_acquire+0x6aa/0x3d50 [ 45.226858] ? lock_acquire+0x1d5/0x580 [ 45.230799] ? lock_acquire+0x1d5/0x580 [ 45.234740] ? lock_timer_base+0x1a3/0x2b0 [ 45.238943] ? find_held_lock+0x35/0x1d0 [ 45.242979] ? sock_def_wakeup+0x1f9/0x350 [ 45.247180] ? lock_downgrade+0x990/0x990 [ 45.251297] ? lock_release+0xa40/0xa40 [ 45.255241] sctp_outq_free+0x15/0x20 [ 45.259008] sctp_association_free+0x2d0/0x930 [ 45.263561] ? sctp_asconf_queue_teardown+0x700/0x700 [ 45.268717] ? sock_def_wakeup+0x222/0x350 [ 45.272918] ? sk_dst_check+0x560/0x560 [ 45.276859] ? sctp_association_put+0x74/0x2f0 [ 45.281405] ? sctp_association_hold+0x20/0x20 [ 45.285954] ? check_noncircular+0x20/0x20 [ 45.290160] sctp_do_sm+0x271b/0x6a30 [ 45.293938] ? sctp_do_8_2_transport_strike.isra.16+0x8a0/0x8a0 [ 45.299967] ? print_irqtrace_events+0x270/0x270 [ 45.304686] ? __lock_acquire+0x6aa/0x3d50 [ 45.308883] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 45.314034] ? __lock_acquire+0x6aa/0x3d50 [ 45.318237] ? print_irqtrace_events+0x270/0x270 [ 45.322970] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 45.328128] ? find_held_lock+0x35/0x1d0 [ 45.332161] ? skb_dequeue+0x12a/0x180 [ 45.336014] ? lock_downgrade+0x990/0x990 [ 45.340133] ? do_raw_spin_trylock+0x190/0x190 [ 45.344684] ? mark_held_locks+0xaf/0x100 [ 45.348807] ? trace_hardirqs_on+0xd/0x10 [ 45.352927] sctp_primitive_SHUTDOWN+0xa0/0xd0 [ 45.357478] sctp_close+0x3c6/0x980 [ 45.361070] ? is_bpf_text_address+0xa4/0x120 [ 45.365541] ? sctp_apply_peer_addr_params+0xf30/0xf30 [ 45.370786] ? __save_stack_trace+0x7e/0xd0 [ 45.375075] ? check_noncircular+0x20/0x20 [ 45.379280] ? depot_save_stack+0x12c/0x490 [ 45.383573] ? locks_remove_file+0x3fa/0x5a0 [ 45.387949] ? fcntl_setlk+0x10c0/0x10c0 [ 45.391975] ? free_fs_struct+0x4f/0x60 [ 45.395917] ? __fsnotify_parent+0xb4/0x3a0 [ 45.400203] ? ip_mc_drop_socket+0x1ce/0x230 [ 45.404583] inet_release+0xed/0x1c0 [ 45.408266] sock_release+0x8d/0x1e0 [ 45.411949] ? sock_release+0x1e0/0x1e0 [ 45.415890] sock_close+0x16/0x20 [ 45.419312] __fput+0x327/0x7e0 [ 45.422565] ? fput+0x140/0x140 [ 45.425814] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.430280] ____fput+0x15/0x20 [ 45.433527] task_work_run+0x199/0x270 [ 45.437383] ? task_work_cancel+0x210/0x210 [ 45.441670] ? _raw_spin_unlock+0x22/0x30 [ 45.445784] ? switch_task_namespaces+0x87/0xc0 [ 45.450423] do_exit+0x9b5/0x1ad0 [ 45.453849] ? mm_update_next_owner+0x930/0x930 [ 45.458490] ? trace_event_raw_event_sched_switch+0x8a0/0x8a0 [ 45.464343] ? rcu_note_context_switch+0x710/0x710 [ 45.469240] ? futex_wait_setup+0x14a/0x3d0 [ 45.473532] ? __might_sleep+0x95/0x190 [ 45.477480] ? find_held_lock+0x35/0x1d0 [ 45.481513] ? futex_wait+0x402/0x990 [ 45.485279] ? lock_downgrade+0x990/0x990 [ 45.489399] ? do_raw_spin_trylock+0x190/0x190 [ 45.493948] ? check_noncircular+0x20/0x20 [ 45.498165] ? mmdrop+0x18/0x30 [ 45.501411] ? drop_futex_key_refs.isra.13+0x63/0xa0 [ 45.506481] ? futex_wait+0x69e/0x990 [ 45.511297] ? find_held_lock+0x35/0x1d0 [ 45.515346] ? get_signal+0x7ae/0x16d0 [ 45.519214] ? lock_downgrade+0x990/0x990 [ 45.523348] do_group_exit+0x149/0x400 [ 45.527217] ? __lock_is_held+0xb6/0x140 [ 45.531248] ? SyS_exit+0x30/0x30 [ 45.534673] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.539139] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.544139] get_signal+0x73f/0x16d0 [ 45.547832] ? ptrace_notify+0x130/0x130 [ 45.551865] ? __fd_install+0x2da/0x6a0 [ 45.555818] ? lock_downgrade+0x990/0x990 [ 45.559947] ? exit_robust_list+0x240/0x240 [ 45.564252] do_signal+0x94/0x1ee0 [ 45.567759] ? __fd_install+0x2f7/0x6a0 [ 45.571702] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.576431] ? get_unused_fd_flags+0x190/0x190 [ 45.580988] ? setup_sigcontext+0x7d0/0x7d0 [ 45.585299] ? copy_user_generic_unrolled+0x89/0xc0 [ 45.590286] ? _copy_to_user+0xa2/0xc0 [ 45.594153] ? fput+0xd2/0x140 [ 45.597316] ? SYSC_accept4+0x4ec/0x850 [ 45.601264] ? exit_to_usermode_loop+0x8c/0x310 [ 45.605910] exit_to_usermode_loop+0x214/0x310 [ 45.610465] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 45.615984] syscall_return_slowpath+0x42f/0x510 [ 45.620711] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 45.625698] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 45.630597] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.635585] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.640316] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 45.645041] RIP: 0033:0x452869 [ 45.648201] RSP: 002b:00007f7cb0df0ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 45.655880] RAX: fffffffffffffe00 RBX: 0000000000758100 RCX: 0000000000452869 [ 45.663118] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000758100 [ 45.670356] RBP: 0000000000758100 R08: 0000000000000000 R09: 00000000007580d8 [ 45.677595] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 45.684833] R13: 0000000000a6f7ff R14: 00007f7cb0df19c0 R15: 000000000000000c [ 45.692657] Dumping ftrace buffer: [ 45.696225] (ftrace buffer empty) [ 45.699902] Kernel Offset: disabled [ 45.703497] Rebooting in 86400 seconds..