[....] 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. [ 86.341362][ T27] kauditd_printk_skb: 4 callbacks suppressed [ 86.341374][ T27] audit: type=1800 audit(1581074415.634:29): pid=9711 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 86.368823][ T27] audit: type=1800 audit(1581074415.634:30): pid=9711 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.79' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 96.427018][ T9870] IPVS: ftp: loaded support on port[0] = 21 [ 96.511670][ C0] [ 96.514035][ C0] ================================ [ 96.519129][ C0] WARNING: inconsistent lock state [ 96.524228][ C0] 5.5.0-syzkaller #0 Not tainted [ 96.529177][ C0] -------------------------------- [ 96.534286][ C0] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 96.541215][ C0] ksoftirqd/0/9 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 96.547372][ C0] ffff8880932cb1c8 (&(&local->client_conns_lock)->rlock){+.?.}, at: rxrpc_put_client_conn+0x6ed/0xc90 [ 96.558337][ C0] {SOFTIRQ-ON-W} state was registered at: [ 96.564151][ C0] lock_acquire+0x190/0x410 [ 96.568820][ C0] _raw_spin_lock+0x2f/0x40 [ 96.573397][ C0] rxrpc_connect_call+0x358/0x4e30 [ 96.578594][ C0] rxrpc_new_client_call+0x9c0/0x1ad0 [ 96.584052][ C0] rxrpc_do_sendmsg+0xffa/0x1d5f [ 96.589061][ C0] rxrpc_sendmsg+0x4d6/0x5f0 [ 96.593770][ C0] sock_sendmsg+0xd7/0x130 [ 96.598255][ C0] ____sys_sendmsg+0x358/0x880 [ 96.603082][ C0] ___sys_sendmsg+0x100/0x170 [ 96.607833][ C0] __sys_sendmmsg+0x1bf/0x4d0 [ 96.612601][ C0] __x64_sys_sendmmsg+0x9d/0x100 [ 96.617762][ C0] do_syscall_64+0xfa/0x790 [ 96.622344][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 96.628447][ C0] irq event stamp: 538342 [ 96.632780][ C0] hardirqs last enabled at (538342): [] _raw_spin_unlock_irqrestore+0x66/0xe0 [ 96.643267][ C0] hardirqs last disabled at (538341): [] _raw_spin_lock_irqsave+0x6f/0xcd [ 96.653408][ C0] softirqs last enabled at (538324): [] __do_softirq+0x6cd/0x98c [ 96.662859][ C0] softirqs last disabled at (538329): [] run_ksoftirqd+0x8e/0x110 [ 96.672392][ C0] [ 96.672392][ C0] other info that might help us debug this: [ 96.684066][ C0] Possible unsafe locking scenario: [ 96.684066][ C0] [ 96.691584][ C0] CPU0 [ 96.694846][ C0] ---- [ 96.698100][ C0] lock(&(&local->client_conns_lock)->rlock); [ 96.704342][ C0] [ 96.707779][ C0] lock(&(&local->client_conns_lock)->rlock); [ 96.714118][ C0] [ 96.714118][ C0] *** DEADLOCK *** [ 96.714118][ C0] [ 96.722256][ C0] 1 lock held by ksoftirqd/0/9: [ 96.727105][ C0] #0: ffffffff89bac140 (rcu_callback){....}, at: rcu_core+0x562/0x1390 [ 96.735443][ C0] [ 96.735443][ C0] stack backtrace: [ 96.741345][ C0] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.5.0-syzkaller #0 [ 96.749400][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 96.760155][ C0] Call Trace: [ 96.763492][ C0] dump_stack+0x197/0x210 [ 96.767832][ C0] print_usage_bug.cold+0x327/0x378 [ 96.773013][ C0] mark_lock+0xbb4/0x1220 [ 96.777339][ C0] ? check_usage_backwards+0x330/0x330 [ 96.782788][ C0] ? lock_downgrade+0x920/0x920 [ 96.787776][ C0] __lock_acquire+0x1e8e/0x4a00 [ 96.792612][ C0] ? find_held_lock+0x35/0x130 [ 96.797374][ C0] ? __kasan_check_read+0x11/0x20 [ 96.802447][ C0] ? mark_lock+0xc2/0x1220 [ 96.807068][ C0] ? mark_held_locks+0xf0/0xf0 [ 96.811819][ C0] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 96.817622][ C0] lock_acquire+0x190/0x410 [ 96.822113][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 96.827746][ C0] _raw_spin_lock+0x2f/0x40 [ 96.832245][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 96.837690][ C0] rxrpc_put_client_conn+0x6ed/0xc90 [ 96.843116][ C0] ? rxrpc_rcu_destroy_call+0xbd/0x200 [ 96.848557][ C0] rxrpc_rcu_destroy_call+0xbd/0x200 [ 96.853844][ C0] rcu_core+0x5e1/0x1390 [ 96.858166][ C0] ? __rcu_read_unlock+0x700/0x700 [ 96.863279][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 96.868815][ C0] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 96.875189][ C0] rcu_core_si+0x9/0x10 [ 96.879758][ C0] __do_softirq+0x262/0x98c [ 96.884247][ C0] ? takeover_tasklets+0x820/0x820 [ 96.889362][ C0] run_ksoftirqd+0x8e/0x110 [ 96.893869][ C0] smpboot_thread_fn+0x6a3/0xa40 [ 96.898795][ C0] ? __smpboot_create_thread.part.0+0x340/0x340 [ 96.905359][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 96.91254