[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 90.867835][ T27] audit: type=1800 audit(1581108466.819:25): pid=9550 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 90.889789][ T27] audit: type=1800 audit(1581108466.819:26): pid=9550 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 90.936509][ T27] audit: type=1800 audit(1581108466.829:27): pid=9550 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 '10.128.0.45' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 102.841417][ T9702] IPVS: ftp: loaded support on port[0] = 21 [ 102.936552][ C1] [ 102.938926][ C1] ================================ [ 102.944007][ C1] WARNING: inconsistent lock state [ 102.949091][ C1] 5.5.0-syzkaller #0 Not tainted [ 102.954112][ C1] -------------------------------- [ 102.959485][ C1] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 102.966325][ C1] swapper/1/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 102.972381][ C1] ffff8880a21e39c8 (&(&local->client_conns_lock)->rlock){+.?.}, at: rxrpc_put_client_conn+0x6ed/0xc90 [ 102.983401][ C1] {SOFTIRQ-ON-W} state was registered at: [ 102.989186][ C1] lock_acquire+0x190/0x410 [ 102.993863][ C1] _raw_spin_lock+0x2f/0x40 [ 102.998433][ C1] rxrpc_connect_call+0x358/0x4e30 [ 103.003623][ C1] rxrpc_new_client_call+0x9c0/0x1ad0 [ 103.009131][ C1] rxrpc_do_sendmsg+0xffa/0x1d5f [ 103.014164][ C1] rxrpc_sendmsg+0x4d6/0x5f0 [ 103.018830][ C1] sock_sendmsg+0xd7/0x130 [ 103.023317][ C1] ____sys_sendmsg+0x358/0x880 [ 103.028158][ C1] ___sys_sendmsg+0x100/0x170 [ 103.033046][ C1] __sys_sendmmsg+0x1bf/0x4d0 [ 103.038027][ C1] __x64_sys_sendmmsg+0x9d/0x100 [ 103.043214][ C1] do_syscall_64+0xfa/0x790 [ 103.048164][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 103.054353][ C1] irq event stamp: 192674 [ 103.058855][ C1] hardirqs last enabled at (192674): [] _raw_spin_unlock_irqrestore+0x66/0xe0 [ 103.069534][ C1] hardirqs last disabled at (192673): [] _raw_spin_lock_irqsave+0x6f/0xcd [ 103.079826][ C1] softirqs last enabled at (192598): [] _local_bh_enable+0x1c/0x30 [ 103.089588][ C1] softirqs last disabled at (192599): [] irq_exit+0x19b/0x1e0 [ 103.098591][ C1] [ 103.098591][ C1] other info that might help us debug this: [ 103.106668][ C1] Possible unsafe locking scenario: [ 103.106668][ C1] [ 103.114109][ C1] CPU0 [ 103.117378][ C1] ---- [ 103.120647][ C1] lock(&(&local->client_conns_lock)->rlock); [ 103.126937][ C1] [ 103.130391][ C1] lock(&(&local->client_conns_lock)->rlock); [ 103.137635][ C1] [ 103.137635][ C1] *** DEADLOCK *** [ 103.137635][ C1] [ 103.145952][ C1] 1 lock held by swapper/1/0: [ 103.150618][ C1] #0: ffffffff89bac140 (rcu_callback){....}, at: rcu_core+0x562/0x1390 [ 103.159034][ C1] [ 103.159034][ C1] stack backtrace: [ 103.164915][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.5.0-syzkaller #0 [ 103.172454][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 103.182878][ C1] Call Trace: [ 103.186161][ C1] [ 103.189014][ C1] dump_stack+0x197/0x210 [ 103.193540][ C1] print_usage_bug.cold+0x327/0x378 [ 103.198848][ C1] mark_lock+0xbb4/0x1220 [ 103.203177][ C1] ? kfree+0x10a/0x2c0 [ 103.207295][ C1] ? check_usage_backwards+0x330/0x330 [ 103.212759][ C1] ? __nf_hook_entries_free+0x31/0x40 [ 103.218134][ C1] __lock_acquire+0x1e8e/0x4a00 [ 103.222984][ C1] ? find_held_lock+0x35/0x130 [ 103.227960][ C1] ? __kasan_check_read+0x11/0x20 [ 103.233009][ C1] ? mark_lock+0xc2/0x1220 [ 103.237539][ C1] ? mark_held_locks+0xf0/0xf0 [ 103.242386][ C1] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 103.248197][ C1] lock_acquire+0x190/0x410 [ 103.252854][ C1] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 103.258605][ C1] _raw_spin_lock+0x2f/0x40 [ 103.263293][ C1] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 103.268782][ C1] rxrpc_put_client_conn+0x6ed/0xc90 [ 103.274183][ C1] ? rxrpc_rcu_destroy_call+0xbd/0x200 [ 103.279639][ C1] rxrpc_rcu_destroy_call+0xbd/0x200 [ 103.284934][ C1] rcu_core+0x5e1/0x1390 [ 103.289187][ C1] ? __rcu_read_unlock+0x700/0x700 [ 103.294306][ C1] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 103.299842][ C1] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 103.305839][ C1] ? run_rebalance_domains+0x227/0x2d0 [ 103.311381][ C1] rcu_core_si+0x9/0x10 [ 103.316213][ C1] __do_softirq+0x262/0x98c [ 103.320718][ C1] ? sched_clock_cpu+0x1b/0x1b0 [ 103.325574][ C1] irq_exit+0x19b/0x1e0 [ 103.329867][ C1] smp_apic_timer_interrupt+0x1a3/0x610 [ 103.335559][ C1] apic_timer_interrupt+0xf/0x20 [ 103.340492][ C1] [ 103.343430][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 103.348803][ C1] 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 [ 103.368397][ C1] RSP: 0018:ffffc90000d3fd68 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 103.376886][ C1] RAX: 1ffffffff1367612 RBX: ffff8880a99fc340 RCX: 0000000000000000 [ 103.384861][ C1] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffff8880a99fcbd4 [ 103.393155][ C1] RBP: ffffc90000d3fd98 R08: ffff8880a99fc340 R09: 0000000000000000 [ 103.401166][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 [ 103.409136][ C1] R13: ffffffff8aa522c0 R14: 0000000000000000 R15: 0000000000000001 [ 103.417217][ C1] ? default_idle+0x4e/0x360 [ 103.421811][ C1] arch_cpu_idle+0xa/0x10 [ 103.426149][ C1] default_idle_call+0x84/0xb0 [ 103.431428][ C1] do_idle+0x3c8/0x6e0 [ 103.435633][ C1] ? arch_cpu_idle