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..