[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 85.371797][ T23] audit: type=1800 audit(1581095222.006:25): pid=9538 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 85.402820][ T23] audit: type=1800 audit(1581095222.016:26): pid=9538 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 85.450493][ T23] audit: type=1800 audit(1581095222.016:27): pid=9538 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] 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 '10.128.0.142' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 97.181035][ T9692] IPVS: ftp: loaded support on port[0] = 21 [ 97.232868][ C0] [ 97.235312][ C0] ================================ [ 97.240401][ C0] WARNING: inconsistent lock state [ 97.245793][ C0] 5.5.0-syzkaller #0 Not tainted [ 97.251025][ C0] -------------------------------- [ 97.256128][ C0] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 97.262968][ C0] swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 97.269194][ C0] ffff8880a86591c8 (&(&local->client_conns_lock)->rlock){+.?.}, at: rxrpc_put_client_conn+0x6ed/0xc90 [ 97.280497][ C0] {SOFTIRQ-ON-W} state was registered at: [ 97.286605][ C0] lock_acquire+0x190/0x410 [ 97.291203][ C0] _raw_spin_lock+0x2f/0x40 [ 97.295975][ C0] rxrpc_connect_call+0x358/0x4e30 [ 97.301390][ C0] rxrpc_new_client_call+0x9c0/0x1ad0 [ 97.307206][ C0] rxrpc_do_sendmsg+0xffa/0x1d5f [ 97.312351][ C0] rxrpc_sendmsg+0x4d6/0x5f0 [ 97.317306][ C0] sock_sendmsg+0xd7/0x130 [ 97.321818][ C0] ____sys_sendmsg+0x358/0x880 [ 97.326659][ C0] ___sys_sendmsg+0x100/0x170 [ 97.331651][ C0] __sys_sendmmsg+0x1bf/0x4d0 [ 97.336413][ C0] __x64_sys_sendmmsg+0x9d/0x100 [ 97.341449][ C0] do_syscall_64+0xfa/0x790 [ 97.346039][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.352087][ C0] irq event stamp: 198704 [ 97.356538][ C0] hardirqs last enabled at (198704): [] _raw_spin_unlock_irqrestore+0x66/0xe0 [ 97.367459][ C0] hardirqs last disabled at (198703): [] _raw_spin_lock_irqsave+0x6f/0xcd [ 97.377633][ C0] softirqs last enabled at (198604): [] _local_bh_enable+0x1c/0x30 [ 97.387268][ C0] softirqs last disabled at (198605): [] irq_exit+0x19b/0x1e0 [ 97.396362][ C0] [ 97.396362][ C0] other info that might help us debug this: [ 97.404682][ C0] Possible unsafe locking scenario: [ 97.404682][ C0] [ 97.412271][ C0] CPU0 [ 97.415566][ C0] ---- [ 97.418840][ C0] lock(&(&local->client_conns_lock)->rlock); [ 97.425163][ C0] [ 97.428806][ C0] lock(&(&local->client_conns_lock)->rlock); [ 97.435121][ C0] [ 97.435121][ C0] *** DEADLOCK *** [ 97.435121][ C0] [ 97.443548][ C0] 1 lock held by swapper/0/0: [ 97.448308][ C0] #0: ffffffff89bac140 (rcu_callback){....}, at: rcu_core+0x562/0x1390 [ 97.456711][ C0] [ 97.456711][ C0] stack backtrace: [ 97.462590][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-syzkaller #0 [ 97.470126][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 97.480372][ C0] Call Trace: [ 97.483951][ C0] [ 97.487015][ C0] dump_stack+0x197/0x210 [ 97.491429][ C0] print_usage_bug.cold+0x327/0x378 [ 97.496620][ C0] mark_lock+0xbb4/0x1220 [ 97.500946][ C0] ? kfree+0x10a/0x2c0 [ 97.505093][ C0] ? check_usage_backwards+0x330/0x330 [ 97.510752][ C0] ? __nf_hook_entries_free+0x31/0x40 [ 97.516122][ C0] __lock_acquire+0x1e8e/0x4a00 [ 97.520967][ C0] ? find_held_lock+0x35/0x130 [ 97.525732][ C0] ? __kasan_check_read+0x11/0x20 [ 97.531032][ C0] ? mark_lock+0xc2/0x1220 [ 97.535618][ C0] ? mark_held_locks+0xf0/0xf0 [ 97.540464][ C0] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 97.546658][ C0] lock_acquire+0x190/0x410 [ 97.551277][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 97.557092][ C0] _raw_spin_lock+0x2f/0x40 [ 97.561722][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 97.567411][ C0] rxrpc_put_client_conn+0x6ed/0xc90 [ 97.572774][ C0] ? rxrpc_rcu_destroy_call+0xbd/0x200 [ 97.578282][ C0] rxrpc_rcu_destroy_call+0xbd/0x200 [ 97.583664][ C0] rcu_core+0x5e1/0x1390 [ 97.587904][ C0] ? __rcu_read_unlock+0x700/0x700 [ 97.593132][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 97.598742][ C0] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 97.604824][ C0] ? run_rebalance_domains+0x227/0x2d0 [ 97.610411][ C0] rcu_core_si+0x9/0x10 [ 97.614683][ C0] __do_softirq+0x262/0x98c [ 97.619346][ C0] ? sched_clock_cpu+0x1b/0x1b0 [ 97.624268][ C0] irq_exit+0x19b/0x1e0 [ 97.628522][ C0] smp_apic_timer_interrupt+0x1a3/0x610 [ 97.634206][ C0] apic_timer_interrupt+0xf/0x20 [ 97.639126][ C0] [ 97.642282][ C0] RIP: 0010:native_safe_halt+0xe/0x10 [ 97.647972][ C0] Code: 48 70 c7 f9 eb 8a cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 44 d3 5b 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 34 d3 5b 00 fb f4 cc 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 7e 2f 76 f9 e8 19 [ 97.667693][ C0] RSP: 0018:ffffffff89a07ce8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 97.676314][ C0] RAX: 1ffffffff1367612 RBX: ffffffff89a7a440 RCX: 0000000000000000 [ 97.684514][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff89a7acd4 [ 97.692476][ C0] RBP: ffffffff89a07d18 R08: ffffffff89a7a440 R09: 0000000000000000 [ 97.700737][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 [ 97.708705][ C0] R13: ffffffff8aa522c0 R14: 0000000000000000 R15: 0000000000000000 [ 97.716882][ C0] ? default_idle+0x4e/0x360 [ 97.721983][ C0] arch_cpu_idle+0xa/0x10 [ 97.726315][ C0] default_idle_call+0x84/0xb0 [ 97.731070][ C0] do_idle+0x3c8/0x6e0 [ 97.735266][ C0] ? arch_cpu_idle_exit+0x80/0x80 [ 97.740288][ C0] ? trace_hardirqs_on+0x67/0x240 [ 97.745387][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 97.751954][ C0] ? debug_smp_processor_id+0x33/0x18a [ 97.757470][ C0] cpu_startup_entry+0x1b/0x20 [ 97.762279][ C0] rest_init+0x23b/0x371 [ 97.766526][ C0] ? trace_init_perf_perm_irq_work_exit+0xe/0xe [ 97.772877][ C0] arch_call_rest_init+0xe/0x1b [ 97.777731][ C0] start_kernel+0x886/0x8c5 [ 97.782963][ C0] ? mem_