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-386-4,10.128.15.209' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 40.621996] refcount_t: underflow; use-after-free. [ 40.622819] ------------[ cut here ]------------ [ 40.623572] WARNING: CPU: 0 PID: 2987 at lib/refcount.c:186 refcount_sub_and_test+0x167/0x1b0 [ 40.624900] Kernel panic - not syncing: panic_on_warn set ... [ 40.624900] [ 40.625870] CPU: 0 PID: 2987 Comm: syzkaller232593 Not tainted 4.14.0-rc5+ #50 [ 40.626833] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.628064] Call Trace: [ 40.628422] dump_stack+0x194/0x257 [ 40.628914] ? arch_local_irq_restore+0x53/0x53 [ 40.629548] panic+0x1e4/0x417 [ 40.629980] ? __warn+0x1d9/0x1d9 [ 40.630448] ? show_regs_print_info+0x65/0x65 [ 40.631062] ? refcount_sub_and_test+0x167/0x1b0 [ 40.631699] __warn+0x1c4/0x1d9 [ 40.632170] ? refcount_sub_and_test+0x167/0x1b0 [ 40.632806] report_bug+0x211/0x2d0 [ 40.633302] fixup_bug+0x40/0x90 [ 40.633757] do_trap+0x260/0x390 [ 40.634218] do_error_trap+0x120/0x390 [ 40.634744] ? do_trap+0x390/0x390 [ 40.635222] ? refcount_sub_and_test+0x167/0x1b0 [ 40.635858] ? vprintk_emit+0x3ea/0x590 [ 40.636415] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 40.637068] do_invalid_op+0x1b/0x20 [ 40.637568] invalid_op+0x18/0x20 [ 40.638032] RIP: 0010:refcount_sub_and_test+0x167/0x1b0 [ 40.638751] RSP: 0018:ffff8801d1c067e0 EFLAGS: 00010282 [ 40.639492] RAX: 0000000000000026 RBX: 0000000000000001 RCX: 0000000000000000 [ 40.640461] RDX: 0000000000000026 RSI: 1ffff1003a380cbc RDI: ffffed003a380cf0 [ 40.641416] RBP: ffff8801d1c06870 R08: 0000000000000001 R09: 0000000000000000 [ 40.643906] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1003a380cfd [ 40.651146] R13: 00000000ffffff01 R14: 0000000000000100 R15: ffff8801d02e3a3c [ 40.658408] ? refcount_inc+0x50/0x50 [ 40.662175] ? __sctp_outq_teardown+0xc7d/0x15a0 [ 40.666898] ? sctp_association_free+0x2d0/0x930 [ 40.671620] ? sctp_do_sm+0x28e7/0x6dd0 [ 40.675561] ? sctp_primitive_SHUTDOWN+0xa0/0xd0 [ 40.680285] ? sctp_close+0x3c6/0x980 [ 40.684054] ? inet_release+0xed/0x1c0 [ 40.687915] sctp_wfree+0x183/0x620 [ 40.691510] ? __sctp_write_space+0x910/0x910 [ 40.695976] skb_release_head_state+0x124/0x200 [ 40.700616] skb_release_all+0x15/0x60 [ 40.704470] consume_skb+0x153/0x490 [ 40.708150] ? sctp_chunk_put+0x99/0x420 [ 40.712178] ? alloc_skb_with_frags+0x710/0x710 [ 40.716816] ? sctp_chunk_hold+0x20/0x20 [ 40.720848] ? refcount_sub_and_test+0x115/0x1b0 [ 40.725571] ? refcount_inc+0x50/0x50 [ 40.729337] ? mark_held_locks+0xaf/0x100 [ 40.733454] ? sctp_datamsg_put+0x456/0x560 [ 40.737750] sctp_chunk_put+0x29c/0x420 [ 40.741694] ? sctp_chunk_hold+0x20/0x20 [ 40.745725] ? sctp_transport_dst_confirm+0x50/0x50 [ 40.750710] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 40.755865] ? lock_release+0xa40/0xa40 [ 40.759808] ? bpf_prog_kallsyms_find+0xbd/0x440 [ 40.764532] ? show_initstate+0xb0/0xb0 [ 40.768478] sctp_chunk_free+0x53/0x60 [ 40.772334] __sctp_outq_teardown+0xc7d/0x15a0 [ 40.776892] ? sctp_inq_set_th_handler+0x1b0/0x1b0 [ 40.781791] ? rcutorture_record_progress+0x10/0x10 [ 40.786781] ? kernel_text_address+0x102/0x140 [ 40.791333] ? unwind_get_return_address+0x61/0xa0 [ 40.796229] ? __save_stack_trace+0x7e/0xd0 [ 40.800520] ? add_lock_to_list.isra.33+0x292/0x39b [ 40.805504] ? print_lockdep_cache.isra.36+0xe6/0xe6 [ 40.810576] ? check_noncircular+0x20/0x20 [ 40.814774] ? graph_lock+0x170/0x170 [ 40.818541] ? print_irqtrace_events+0x270/0x270 [ 40.823276] ? lock_acquire+0x1d5/0x580 [ 40.827215] ? lock_acquire+0x1d5/0x580 [ 40.831157] ? lock_timer_base+0x1a3/0x2b0 [ 40.835364] ? find_held_lock+0x35/0x1d0 [ 40.839398] ? sock_def_wakeup+0x1f9/0x350 [ 40.843601] ? lock_downgrade+0x990/0x990 [ 40.847718] ? lock_release+0xa40/0xa40 [ 40.851665] sctp_outq_free+0x15/0x20 [ 40.855434] sctp_association_free+0x2d0/0x930 [ 40.859984] ? sctp_asconf_queue_teardown+0x700/0x700 [ 40.865139] ? sock_def_wakeup+0x222/0x350 [ 40.869338] ? sk_dst_check+0x560/0x560 [ 40.873281] ? sctp_association_put+0x74/0x2f0 [ 40.877828] ? sctp_association_hold+0x20/0x20 [ 40.882376] ? print_irqtrace_events+0x270/0x270 [ 40.887105] sctp_do_sm+0x28e7/0x6dd0 [ 40.890884] ? sctp_do_8_2_transport_strike.isra.16+0x8a0/0x8a0 [ 40.896913] ? print_irqtrace_events+0x270/0x270 [ 40.901653] ? print_irqtrace_events+0x270/0x270 [ 40.906389] ? find_held_lock+0x35/0x1d0 [ 40.910420] ? skb_dequeue+0x12a/0x180 [ 40.914272] ? lock_downgrade+0x990/0x990 [ 40.918392] ? do_raw_spin_trylock+0x190/0x190 [ 40.922945] ? mark_held_locks+0xaf/0x100 [ 40.927068] ? trace_hardirqs_on+0xd/0x10 [ 40.931188] sctp_primitive_SHUTDOWN+0xa0/0xd0 [ 40.935742] sctp_close+0x3c6/0x980 [ 40.939346] ? sctp_apply_peer_addr_params+0xf30/0xf30 [ 40.944590] ? unwind_get_return_address+0x61/0xa0 [ 40.949489] ? check_noncircular+0x20/0x20 [ 40.953691] ? check_noncircular+0x20/0x20 [ 40.957899] ? ipv6_sock_ac_close+0x2e8/0x3e0 [ 40.962364] ? ipv6_sock_mc_close+0x148/0x1a0 [ 40.966825] ? ip_mc_drop_socket+0x1ce/0x230 [ 40.971199] ? __fsnotify_parent+0xb4/0x3a0 [ 40.975487] inet_release+0xed/0x1c0 [ 40.979167] inet6_release+0x50/0x70 [ 40.982851] sock_release+0x8d/0x1e0 [ 40.986531] ? sock_release+0x1e0/0x1e0 [ 40.990468] sock_close+0x16/0x20 [ 40.993888] __fput+0x327/0x7e0 [ 40.997139] ? fput+0x140/0x140 [ 41.000388] ? _raw_spin_unlock_irq+0x27/0x70 [ 41.004853] ____fput+0x15/0x20 [ 41.008098] task_work_run+0x199/0x270 [ 41.011953] ? task_work_cancel+0x210/0x210 [ 41.016241] ? _raw_spin_unlock+0x22/0x30 [ 41.020354] ? switch_task_namespaces+0x87/0xc0 [ 41.024995] do_exit+0x9b5/0x1ad0 [ 41.028412] ? __fd_install+0x2da/0x6a0 [ 41.032364] ? mm_update_next_owner+0x930/0x930 [ 41.037002] ? __lock_is_held+0xb6/0x140 [ 41.041043] ? __fd_install+0x2f7/0x6a0 [ 41.044989] ? get_unused_fd_flags+0x190/0x190 [ 41.049545] ? __might_sleep+0x95/0x190 [ 41.053494] ? kasan_check_read+0x11/0x20 [ 41.057606] ? _copy_to_user+0xa2/0xc0 [ 41.061464] ? fd_install+0x4d/0x60 [ 41.065059] ? SYSC_accept4+0x4ec/0x850 [ 41.068994] ? __release_sock+0x360/0x360 [ 41.073111] ? kernel_accept+0x2f0/0x2f0 [ 41.077141] ? sctp_inet_listen+0x141/0x850 [ 41.081429] ? sctp_transport_get_idx+0x70/0x70 [ 41.086065] ? selinux_socket_listen+0x36/0x40 [ 41.090612] ? security_socket_listen+0x81/0xb0 [ 41.095252] do_group_exit+0x149/0x400 [ 41.099104] ? SyS_bind+0x30/0x30 [ 41.102519] ? __do_page_fault+0x3d6/0xd60 [ 41.106718] ? SyS_exit+0x30/0x30 [ 41.110146] ? do_fast_syscall_32+0x158/0xf05 [ 41.114605] ? do_group_exit+0x400/0x400 [ 41.118630] SyS_exit_group+0x1d/0x20 [ 41.122395] do_fast_syscall_32+0x3f2/0xf05 [ 41.126686] ? do_int80_syscall_32+0x940/0x940 [ 41.131234] ? kasan_check_read+0x11/0x20 [ 41.135348] ? syscall_return_slowpath+0x510/0x510 [ 41.140244] ? SyS_rt_sigaction+0x94/0x1b0 [ 41.144443] ? SyS_sigprocmask+0x4b0/0x4b0 [ 41.148642] ? SyS_read+0x184/0x220 [ 41.152236] ? sysret32_from_system_call+0x5/0x3b [ 41.157048] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.161862] entry_SYSENTER_compat+0x51/0x60 [ 41.166235] RIP: 0023:0xf7ff5c79 [ 41.169562] RSP: 002b:00000000fff9e1dc EFLAGS: 00000292 ORIG_RAX: 00000000000000fc [ 41.177233] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080eb298 [ 41.184469] RDX: 0000000000000000 RSI: 00000000080d5858 RDI: 00000000080eb2a0 [ 41.191707] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 41.198945] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 41.206180] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 41.213587] Dumping ftrace buffer: [ 41.217160] (ftrace buffer empty) [ 41.220839] Kernel Offset: disabled [ 41.224434] Rebooting in 86400 seconds..