[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 88.879178][ T27] audit: type=1800 audit(1581132768.575:25): pid=9590 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 88.910698][ T27] audit: type=1800 audit(1581132768.575:26): pid=9590 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 88.954029][ T27] audit: type=1800 audit(1581132768.575:27): pid=9590 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 '10.128.0.243' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 100.004770][ T9746] IPVS: ftp: loaded support on port[0] = 21 [ 100.073146][ C0] [ 100.076710][ C0] ================================ [ 100.081793][ C0] WARNING: inconsistent lock state [ 100.086908][ C0] 5.5.0-syzkaller #0 Not tainted [ 100.091836][ C0] -------------------------------- [ 100.096919][ C0] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 100.103741][ C0] swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 100.109707][ C0] ffff8880a943c9c8 (&(&local->client_conns_lock)->rlock){+.?.}, at: rxrpc_put_client_conn+0x6ed/0xc90 [ 100.121511][ C0] {SOFTIRQ-ON-W} state was registered at: [ 100.127210][ C0] lock_acquire+0x190/0x410 [ 100.131780][ C0] _raw_spin_lock+0x2f/0x40 [ 100.136346][ C0] rxrpc_connect_call+0x358/0x4e30 [ 100.141520][ C0] rxrpc_new_client_call+0x9c0/0x1ad0 [ 100.147057][ C0] rxrpc_do_sendmsg+0xffa/0x1d5f [ 100.152073][ C0] rxrpc_sendmsg+0x4d6/0x5f0 [ 100.156739][ C0] sock_sendmsg+0xd7/0x130 [ 100.161222][ C0] ____sys_sendmsg+0x358/0x880 [ 100.166077][ C0] ___sys_sendmsg+0x100/0x170 [ 100.170815][ C0] __sys_sendmmsg+0x1bf/0x4d0 [ 100.175552][ C0] __x64_sys_sendmmsg+0x9d/0x100 [ 100.180585][ C0] do_syscall_64+0xfa/0x790 [ 100.185163][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 100.191119][ C0] irq event stamp: 161606 [ 100.195437][ C0] hardirqs last enabled at (161606): [] _raw_spin_unlock_irqrestore+0x66/0xe0 [ 100.205925][ C0] hardirqs last disabled at (161605): [] _raw_spin_lock_irqsave+0x6f/0xcd [ 100.216083][ C0] softirqs last enabled at (161526): [] _local_bh_enable+0x1c/0x30 [ 100.225621][ C0] softirqs last disabled at (161527): [] irq_exit+0x19b/0x1e0 [ 100.234615][ C0] [ 100.234615][ C0] other info that might help us debug this: [ 100.242651][ C0] Possible unsafe locking scenario: [ 100.242651][ C0] [ 100.250079][ C0] CPU0 [ 100.253353][ C0] ---- [ 100.256625][ C0] lock(&(&local->client_conns_lock)->rlock); [ 100.262777][ C0] [ 100.266211][ C0] lock(&(&local->client_conns_lock)->rlock); [ 100.272523][ C0] [ 100.272523][ C0] *** DEADLOCK *** [ 100.272523][ C0] [ 100.280658][ C0] 1 lock held by swapper/0/0: [ 100.285401][ C0] #0: ffffffff89bac140 (rcu_callback){....}, at: rcu_core+0x562/0x1390 [ 100.293757][ C0] [ 100.293757][ C0] stack backtrace: [ 100.299641][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-syzkaller #0 [ 100.307165][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 100.317242][ C0] Call Trace: [ 100.320503][ C0] [ 100.323339][ C0] dump_stack+0x197/0x210 [ 100.327649][ C0] print_usage_bug.cold+0x327/0x378 [ 100.332822][ C0] mark_lock+0xbb4/0x1220 [ 100.337150][ C0] ? kfree+0x10a/0x2c0 [ 100.341195][ C0] ? check_usage_backwards+0x330/0x330 [ 100.346635][ C0] ? __nf_hook_entries_free+0x31/0x40 [ 100.351984][ C0] __lock_acquire+0x1e8e/0x4a00 [ 100.356821][ C0] ? find_held_lock+0x35/0x130 [ 100.361594][ C0] ? __kasan_check_read+0x11/0x20 [ 100.366615][ C0] ? mark_lock+0xc2/0x1220 [ 100.371021][ C0] ? mark_held_locks+0xf0/0xf0 [ 100.375780][ C0] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 100.381577][ C0] lock_acquire+0x190/0x410 [ 100.386066][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 100.391518][ C0] _raw_spin_lock+0x2f/0x40 [ 100.396011][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 100.401452][ C0] rxrpc_put_client_conn+0x6ed/0xc90 [ 100.406741][ C0] ? rxrpc_rcu_destroy_call+0xbd/0x200 [ 100.412177][ C0] rxrpc_rcu_destroy_call+0xbd/0x200 [ 100.417453][ C0] rcu_core+0x5e1/0x1390 [ 100.421688][ C0] ? __rcu_read_unlock+0x700/0x700 [ 100.426776][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 100.432311][ C0] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 100.438268][ C0] ? run_rebalance_domains+0x227/0x2d0 [ 100.443728][ C0] rcu_core_si+0x9/0x10 [ 100.447893][ C0] __do_softirq+0x262/0x98c [ 100.452371][ C0] ? sched_clock_cpu+0x1b/0x1b0 [ 100.457202][ C0] irq_exit+0x19b/0x1e0 [ 100.461338][ C0] smp_apic_timer_interrupt+0x1a3/0x610 [ 100.466861][ C0] apic_timer_interrupt+0xf/0x20 [ 100.471784][ C0] [ 100.474702][ C0] RIP: 0010:native_safe_halt+0xe/0x10 [ 100.480048][ 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 [ 100.499626][ C0] RSP: 0018:ffffffff89a07ce8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 100.508507][ C0] RAX: 1ffffffff1367612 RBX: ffffffff89a7a440 RCX: 0000000000000000 [ 100.516455][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff89a7acd4 [ 100.524499][ C0] RBP: ffffffff89a07d18 R08: ffffffff89a7a440 R09: 0000000000000000 [ 100.532445][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 [ 100.540392][ C0] R13: ffffffff8aa52400 R14: 0000000000000000 R15: 0000000000000000 [ 100.548412][ C0] ? default_idle+0x4e/0x360 [ 100.553025][ C0] arch_cpu_idle+0xa/0x10 [ 100.557373][ C0] default_idle_call+0x84/0xb0 [ 100.562133][ C0] do_idle+0x3c8/0x6e0 [ 100.566181][ C0] ? arch_cpu_idle_exit+0x80/0x80 [ 100.571187][ C0] ? trace_hardirqs_on+0x67/0x240 [ 100.576204][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 100.582420][ C0] ? debug_smp_processor_id+0x33/0x18a [ 100.587855][ C0] cpu_startup_entry+0x1b/0x20 [ 100.592858][ C0] rest_init+0x23b/0x371 [ 100.597084][ C0] ? trace_init_perf_perm_irq_work_exit+0xe/0xe [ 100.603298][ C0] arch_call_rest_init+0xe/0x1b [ 100.608135][ C0] start_kernel+0x886/0x8c5 [ 100.612969][ C0] ? mem_encrypt_init+0xb/0xb [ 100.617631][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 100.623856][