[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 71.429719][ T26] audit: type=1800 audit(1581091329.055:25): pid=9395 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 71.464316][ T26] audit: type=1800 audit(1581091329.055:26): pid=9395 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 71.488252][ T26] audit: type=1800 audit(1581091329.055:27): pid=9395 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 '10.128.1.46' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 82.727547][ T9550] IPVS: ftp: loaded support on port[0] = 21 [ 82.794496][ C0] [ 82.796947][ C0] ================================ [ 82.802073][ C0] WARNING: inconsistent lock state [ 82.807160][ C0] 5.5.0-syzkaller #0 Not tainted [ 82.812067][ C0] -------------------------------- [ 82.817151][ C0] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. [ 82.823973][ C0] swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes: [ 82.829935][ C0] ffff8880a7ba01c8 (&(&local->client_conns_lock)->rlock){+.?.}, at: rxrpc_put_client_conn+0x6ed/0xc90 [ 82.840871][ C0] {SOFTIRQ-ON-W} state was registered at: [ 82.846571][ C0] lock_acquire+0x190/0x410 [ 82.851144][ C0] _raw_spin_lock+0x2f/0x40 [ 82.855709][ C0] rxrpc_connect_call+0x358/0x4e30 [ 82.860881][ C0] rxrpc_new_client_call+0x9c0/0x1ad0 [ 82.866314][ C0] rxrpc_do_sendmsg+0xffa/0x1d5f [ 82.871324][ C0] rxrpc_sendmsg+0x4d6/0x5f0 [ 82.875989][ C0] sock_sendmsg+0xd7/0x130 [ 82.880477][ C0] ____sys_sendmsg+0x358/0x880 [ 82.885310][ C0] ___sys_sendmsg+0x100/0x170 [ 82.890060][ C0] __sys_sendmmsg+0x1bf/0x4d0 [ 82.894795][ C0] __x64_sys_sendmmsg+0x9d/0x100 [ 82.899794][ C0] do_syscall_64+0xfa/0x790 [ 82.904360][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 82.910321][ C0] irq event stamp: 167964 [ 82.914655][ C0] hardirqs last enabled at (167964): [] _raw_spin_unlock_irqrestore+0x66/0xe0 [ 82.925144][ C0] hardirqs last disabled at (167963): [] _raw_spin_lock_irqsave+0x6f/0xcd [ 82.935241][ C0] softirqs last enabled at (167804): [] _local_bh_enable+0x1c/0x30 [ 82.944759][ C0] softirqs last disabled at (167805): [] irq_exit+0x19b/0x1e0 [ 82.953748][ C0] [ 82.953748][ C0] other info that might help us debug this: [ 82.961795][ C0] Possible unsafe locking scenario: [ 82.961795][ C0] [ 82.969231][ C0] CPU0 [ 82.972484][ C0] ---- [ 82.975756][ C0] lock(&(&local->client_conns_lock)->rlock); [ 82.981890][ C0] [ 82.985325][ C0] lock(&(&local->client_conns_lock)->rlock); [ 82.991635][ C0] [ 82.991635][ C0] *** DEADLOCK *** [ 82.991635][ C0] [ 82.999756][ C0] 1 lock held by swapper/0/0: [ 83.004413][ C0] #0: ffffffff89bac140 (rcu_callback){....}, at: rcu_core+0x562/0x1390 [ 83.012721][ C0] [ 83.012721][ C0] stack backtrace: [ 83.019066][ C0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-syzkaller #0 [ 83.026577][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 83.036618][ C0] Call Trace: [ 83.039889][ C0] [ 83.042726][ C0] dump_stack+0x197/0x210 [ 83.047033][ C0] print_usage_bug.cold+0x327/0x378 [ 83.054824][ C0] mark_lock+0xbb4/0x1220 [ 83.059138][ C0] ? kfree+0x10a/0x2c0 [ 83.063180][ C0] ? check_usage_backwards+0x330/0x330 [ 83.068613][ C0] ? __nf_hook_entries_free+0x31/0x40 [ 83.073958][ C0] __lock_acquire+0x1e8e/0x4a00 [ 83.078780][ C0] ? find_held_lock+0x35/0x130 [ 83.083531][ C0] ? __kasan_check_read+0x11/0x20 [ 83.088528][ C0] ? mark_lock+0xc2/0x1220 [ 83.092920][ C0] ? mark_held_locks+0xf0/0xf0 [ 83.097659][ C0] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 83.103441][ C0] lock_acquire+0x190/0x410 [ 83.107925][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 83.113359][ C0] _raw_spin_lock+0x2f/0x40 [ 83.117852][ C0] ? rxrpc_put_client_conn+0x6ed/0xc90 [ 83.123284][ C0] rxrpc_put_client_conn+0x6ed/0xc90 [ 83.128543][ C0] ? rxrpc_rcu_destroy_call+0xbd/0x200 [ 83.133978][ C0] rxrpc_rcu_destroy_call+0xbd/0x200 [ 83.139241][ C0] rcu_core+0x5e1/0x1390 [ 83.143470][ C0] ? __rcu_read_unlock+0x700/0x700 [ 83.148556][ C0] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 83.154073][ C0] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 83.160028][ C0] ? run_rebalance_domains+0x227/0x2d0 [ 83.165460][ C0] rcu_core_si+0x9/0x10 [ 83.169591][ C0] __do_softirq+0x262/0x98c [ 83.174065][ C0] ? sched_clock_cpu+0x1b/0x1b0 [ 83.178895][ C0] irq_exit+0x19b/0x1e0 [ 83.183040][ C0] smp_apic_timer_interrupt+0x1a3/0x610 [ 83.188559][ C0] apic_timer_interrupt+0xf/0x20 [ 83.193477][ C0] [ 83.196406][ C0] RIP: 0010:native_safe_halt+0xe/0x10 [ 83.201772][ 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 [ 83.222490][ C0] RSP: 0018:ffffffff89a07ce8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 83.230875][ C0] RAX: 1ffffffff1367612 RBX: ffffffff89a7a440 RCX: 0000000000000000 [ 83.238831][ C0] RDX: dffffc0000000000 RSI: 0000000000000006 RDI: ffffffff89a7acd4 [ 83.246780][ C0] RBP: ffffffff89a07d18 R08: ffffffff89a7a440 R09: 0000000000000000 [ 83.254743][ C0] R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 [ 83.262689][ C0] R13: ffffffff8aa522c0 R14: 0000000000000000 R15: 0000000000000000 [ 83.270715][ C0] ? default_idle+0x4e/0x360 [ 83.275307][ C0] arch_cpu_idle+0xa/0x10 [ 83.279708][ C0] default_idle_call+0x84/0xb0 [ 83.284565][ C0] do_idle+0x3c8/0x6e0 [ 83.288663][ C0] ? arch_cpu_idle_exit+0x80/0x80 [ 83.293686][ C0] ? trace_hardirqs_on+0x67/0x240 [ 83.298701][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 83.304934][ C0] ? debug_smp_processor_id+0x33/0x18a [ 83.310392][ C0] cpu_startup_entry+0x1b/0x20 [ 83.315186][ C0] rest_init+0x23b/0x371 [ 83.319425][ C0] ? trace_init_perf_perm_irq_work_exit+0xe/0xe [ 83.325679][ C0] arch_call_rest_init+0xe/0x1b [ 83.330519][ C0] start_kernel+0x886/0x8c5 [ 83.335010][ C0] ? mem_encrypt_init+0xb/0xb [ 83.339672][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 83.345906][