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-2,10.128.0.35' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 31.312128] refcount_t: underflow; use-after-free. [ 31.312997] ------------[ cut here ]------------ [ 31.313877] WARNING: CPU: 1 PID: 3003 at lib/refcount.c:186 refcount_sub_and_test+0x167/0x1b0 [ 31.315052] Kernel panic - not syncing: panic_on_warn set ... [ 31.315052] [ 31.316088] CPU: 1 PID: 3003 Comm: syzkaller116454 Not tainted 4.13.0-rc5+ #42 [ 31.317106] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.318325] Call Trace: [ 31.318689] dump_stack+0x194/0x257 [ 31.319182] ? arch_local_irq_restore+0x53/0x53 [ 31.319839] panic+0x1e4/0x417 [ 31.320274] ? __warn+0x1d9/0x1d9 [ 31.320762] ? show_regs_print_info+0x65/0x65 [ 31.321376] ? refcount_sub_and_test+0x167/0x1b0 [ 31.322026] __warn+0x1c4/0x1d9 [ 31.322471] ? refcount_sub_and_test+0x167/0x1b0 [ 31.323108] report_bug+0x211/0x2d0 [ 31.323607] fixup_bug+0x40/0x90 [ 31.324063] do_trap+0x260/0x390 [ 31.324526] do_error_trap+0x120/0x390 [ 31.325049] ? vprintk_emit+0x49b/0x590 [ 31.325586] ? do_trap+0x390/0x390 [ 31.326063] ? refcount_sub_and_test+0x167/0x1b0 [ 31.326700] ? vprintk_emit+0x3ea/0x590 [ 31.327245] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.327908] do_invalid_op+0x1b/0x20 [ 31.328437] invalid_op+0x1e/0x30 [ 31.328920] RIP: 0010:refcount_sub_and_test+0x167/0x1b0 [ 31.329662] RSP: 0018:ffff8801c08be928 EFLAGS: 00010282 [ 31.330376] RAX: 0000000000000026 RBX: 0000000000000001 RCX: 0000000000000000 [ 31.331354] RDX: 0000000000000026 RSI: 1ffff10038117ce5 RDI: ffffed0038117d19 [ 31.332323] RBP: ffff8801c08be9b8 R08: 0000000000000001 R09: 0000000000000000 [ 31.339564] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10038117d26 [ 31.346804] R13: 00000000ffffff01 R14: 0000000000000100 R15: ffff8801d048ca3c [ 31.354071] ? refcount_sub_and_test+0x167/0x1b0 [ 31.358796] ? refcount_inc+0x50/0x50 [ 31.362566] ? __sctp_outq_teardown+0xc7d/0x15a0 [ 31.367290] ? sctp_association_free+0x2d0/0x930 [ 31.372010] ? sctp_do_sm+0x28e7/0x6d90 [ 31.375952] ? sctp_primitive_SHUTDOWN+0xa0/0xd0 [ 31.380675] ? sctp_close+0x3c6/0x980 [ 31.384442] ? inet_release+0xed/0x1c0 [ 31.388302] sctp_wfree+0x183/0x620 [ 31.391899] ? __sctp_write_space+0x910/0x910 [ 31.396369] skb_release_head_state+0x124/0x200 [ 31.401007] skb_release_all+0x15/0x60 [ 31.404861] consume_skb+0x153/0x490 [ 31.408544] ? sctp_chunk_put+0x99/0x420 [ 31.412570] ? pskb_carve+0x1db0/0x1db0 [ 31.416513] ? sctp_chunk_hold+0x20/0x20 [ 31.420545] ? refcount_sub_and_test+0x115/0x1b0 [ 31.425269] ? refcount_inc+0x50/0x50 [ 31.429037] ? mark_held_locks+0xaf/0x100 [ 31.433155] ? sctp_datamsg_put+0x456/0x560 [ 31.437452] sctp_chunk_put+0x29c/0x420 [ 31.441399] ? sctp_chunk_hold+0x20/0x20 [ 31.445433] ? sctp_transport_dst_confirm+0x50/0x50 [ 31.450432] sctp_chunk_free+0x53/0x60 [ 31.454288] __sctp_outq_teardown+0xc7d/0x15a0 [ 31.458845] ? bpf_prog_kallsyms_find+0xbd/0x440 [ 31.463573] ? sctp_inq_set_th_handler+0x1b0/0x1b0 [ 31.468468] ? is_bpf_text_address+0x7b/0x120 [ 31.472934] ? lock_downgrade+0x990/0x990 [ 31.477051] ? lock_release+0xa40/0xa40 [ 31.481000] ? update_stack_state+0x700/0x700 [ 31.485462] ? print_usage_bug+0x480/0x480 [ 31.489675] ? is_bpf_text_address+0xa4/0x120 [ 31.494140] ? __kernel_text_address+0xae/0xe0 [ 31.498690] ? unwind_get_return_address+0x61/0xa0 [ 31.503589] ? __save_stack_trace+0x7e/0xd0 [ 31.507884] ? check_noncircular+0x20/0x20 [ 31.512088] ? print_usage_bug+0x480/0x480 [ 31.516289] ? save_stack_trace+0x16/0x20 [ 31.520404] ? save_trace+0x11f/0x350 [ 31.524175] ? lock_acquire+0x1d5/0x580 [ 31.528116] ? lock_acquire+0x1d5/0x580 [ 31.532060] ? lock_timer_base+0x1a3/0x2b0 [ 31.536266] ? find_held_lock+0x35/0x1d0 [ 31.540303] ? sock_def_wakeup+0x1f9/0x350 [ 31.544506] ? lock_downgrade+0x990/0x990 [ 31.548625] ? lock_release+0xa40/0xa40 [ 31.552577] sctp_outq_free+0x15/0x20 [ 31.556347] sctp_association_free+0x2d0/0x930 [ 31.560905] ? sctp_asconf_queue_teardown+0x700/0x700 [ 31.566064] ? sock_def_wakeup+0x222/0x350 [ 31.570268] ? sk_dst_check+0x560/0x560 [ 31.574211] ? sctp_association_put+0x74/0x2f0 [ 31.578762] ? sctp_association_hold+0x20/0x20 [ 31.583319] ? __kernel_text_address+0xae/0xe0 [ 31.587873] ? sctp_sm_lookup_event+0x95/0x3c0 [ 31.592424] sctp_do_sm+0x28e7/0x6d90 [ 31.596194] ? check_noncircular+0x20/0x20 [ 31.600407] ? sctp_do_8_2_transport_strike.isra.16+0x8a0/0x8a0 [ 31.606437] ? print_usage_bug+0x480/0x480 [ 31.610641] ? print_usage_bug+0x480/0x480 [ 31.614851] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 31.620015] ? find_held_lock+0x35/0x1d0 [ 31.624051] ? skb_dequeue+0x12a/0x180 [ 31.627906] ? lock_downgrade+0x990/0x990 [ 31.632026] ? do_raw_spin_trylock+0x190/0x190 [ 31.636576] ? retint_user+0xf/0x20 [ 31.640176] ? mark_held_locks+0xaf/0x100 [ 31.644301] ? trace_hardirqs_on+0xd/0x10 [ 31.648425] sctp_primitive_SHUTDOWN+0xa0/0xd0 [ 31.652980] sctp_close+0x3c6/0x980 [ 31.656585] ? sctp_apply_peer_addr_params+0xf30/0xf30 [ 31.661831] ? unwind_get_return_address+0x61/0xa0 [ 31.666733] ? __save_stack_trace+0x7e/0xd0 [ 31.671028] ? depot_save_stack+0x12c/0x490 [ 31.675335] ? ipv6_sock_ac_close+0x2e8/0x3e0 [ 31.679805] ? ipv6_sock_mc_close+0x148/0x1a0 [ 31.684267] ? ipv6_sock_ac_drop+0x580/0x580 [ 31.688642] ? ip_mc_drop_socket+0x1ce/0x230 [ 31.693018] ? __fsnotify_parent+0xb4/0x3a0 [ 31.697314] inet_release+0xed/0x1c0 [ 31.700998] inet6_release+0x50/0x70 [ 31.704681] sock_release+0x8d/0x1e0 [ 31.708362] ? sock_release+0x1e0/0x1e0 [ 31.712308] sock_close+0x16/0x20 [ 31.715735] __fput+0x327/0x7e0 [ 31.718988] ? fput+0x140/0x140 [ 31.722251] ? do_raw_spin_trylock+0x190/0x190 [ 31.726805] ? check_same_owner+0x320/0x320 [ 31.731098] ____fput+0x15/0x20 [ 31.734365] task_work_run+0x18a/0x260 [ 31.738225] ? task_work_cancel+0x210/0x210 [ 31.742520] ? _raw_spin_unlock+0x22/0x30 [ 31.746636] ? switch_task_namespaces+0x87/0xc0 [ 31.751282] do_exit+0xa3a/0x1b10 [ 31.754714] ? try_to_wake_up+0xf9/0x1600 [ 31.758832] ? lock_downgrade+0x990/0x990 [ 31.762953] ? mm_update_next_owner+0x930/0x930 [ 31.767589] ? do_raw_spin_trylock+0x190/0x190 [ 31.772139] ? do_raw_spin_trylock+0x190/0x190 [ 31.776706] ? trace_hardirqs_off+0xd/0x10 [ 31.780914] ? _raw_spin_unlock_irqrestore+0xa6/0xba [ 31.785986] ? try_to_wake_up+0xf9/0x1600 [ 31.790104] ? do_nanosleep+0x508/0x6f0 [ 31.794048] ? check_noncircular+0x20/0x20 [ 31.798257] ? migrate_swap_stop+0x970/0x970 [ 31.802646] ? rcu_pm_notify+0xc0/0xc0 [ 31.806518] ? find_held_lock+0x35/0x1d0 [ 31.810552] ? retint_kernel+0x10/0x10 [ 31.814409] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.819397] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.824127] ? retint_kernel+0x10/0x10 [ 31.827994] ? _raw_spin_unlock_irq+0x56/0x70 [ 31.832469] do_group_exit+0x149/0x400 [ 31.836330] ? SyS_exit+0x30/0x30 [ 31.839759] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.844754] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.849482] SyS_exit_group+0x1d/0x20 [ 31.853255] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 31.857977] RIP: 0033:0x443fc8 [ 31.861135] RSP: 002b:00007ffd32641a78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 31.868810] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000443fc8 [ 31.876047] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 31.883283] RBP: 0000000000000086 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 31.890520] R10: 00007f4aefc939d0 R11: 0000000000000246 R12: 0000000000000000 [ 31.897759] R13: 00007ffd326419af R14: 00007f4aefc939c0 R15: 0000000000000000 [ 31.905197] Dumping ftrace buffer: [ 31.908779] (ftrace buffer empty) [ 31.912461] Kernel Offset: disabled [ 31.916059] Rebooting in 86400 seconds..