[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 57.461461][ T26] audit: type=1800 audit(1574544556.743:25): pid=8724 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 57.486878][ T26] audit: type=1800 audit(1574544556.743:26): pid=8724 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 57.542324][ T26] audit: type=1800 audit(1574544556.743:27): pid=8724 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 '10.128.0.106' (ECDSA) to the list of known hosts. syzkaller login: [ 663.512156][ T8883] IPVS: ftp: loaded support on port[0] = 21 [ 663.512162][ T8885] IPVS: ftp: loaded support on port[0] = 21 [ 663.520082][ T8884] IPVS: ftp: loaded support on port[0] = 21 [ 663.525497][ T8888] IPVS: ftp: loaded support on port[0] = 21 [ 663.531613][ T8887] IPVS: ftp: loaded support on port[0] = 21 [ 663.538270][ T8886] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program [ 663.767370][ C1] hrtimer: interrupt took 47065 ns [ 768.765918][ C0] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: [ 768.772929][ C0] (detected by 0, t=10502 jiffies, g=7137, q=12) [ 768.779362][ C0] rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295014020-4295003518), jiffies_till_next_fqs=1, root ->qsmask 0x0 [ 768.792712][ C0] syz-executor935 R running task 23704 8896 8886 0x80004000 [ 768.800616][ C0] Call Trace: [ 768.803902][ C0] [ 768.806761][ C0] sched_show_task.cold+0x2ed/0x34e [ 768.811960][ C0] rcu_sched_clock_irq.cold+0xaf4/0xc02 [ 768.817513][ C0] update_process_times+0x2d/0x70 [ 768.822533][ C0] tick_sched_handle+0xa2/0x190 [ 768.827383][ C0] tick_sched_timer+0x53/0x140 [ 768.832231][ C0] __hrtimer_run_queues+0x364/0xe40 [ 768.837426][ C0] ? tick_sched_do_timer+0x1b0/0x1b0 [ 768.842712][ C0] ? hrtimer_init+0x330/0x330 [ 768.847384][ C0] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 768.853191][ C0] ? ktime_get_update_offsets_now+0x2ce/0x430 [ 768.859261][ C0] hrtimer_interrupt+0x314/0x770 [ 768.864532][ C0] smp_apic_timer_interrupt+0x160/0x610 [ 768.870079][ C0] apic_timer_interrupt+0xf/0x20 [ 768.875006][ C0] [ 768.877940][ C0] RIP: 0010:loop2+0x1e5/0x39e [ 768.882612][ C0] Code: 63 7b f0 f0 06 41 21 c7 45 31 f5 c4 63 7b f0 e2 0d 41 31 cf c4 63 7b f0 f2 16 89 d6 45 31 e6 c4 63 7b f0 e2 02 44 03 44 3c 20 <44> 09 d6 45 31 e6 41 89 d4 44 21 ce 45 21 d4 45 01 ef 45 01 c3 44 [ 768.902233][ C0] RSP: 0018:ffff88809dacf080 EFLAGS: 00000a17 ORIG_RAX: ffffffffffffff13 [ 768.910643][ C0] RAX: 000000000d895faf RBX: 00000000af692001 RCX: 00000000c2b12cbe [ 768.918605][ C0] RDX: 00000000398a2513 RSI: 00000000398a2513 RDI: 00000000000001c0 [ 768.926571][ C0] RBP: ffff88809dacf318 R08: 0000000023af5072 R09: 00000000d9fb4f71 [ 768.934665][ C0] R10: 00000000449125ce R11: 00000000c47f205e R12: 00000000ce628944 [ 768.942649][ C0] R13: 000000008d7843d3 R14: 00000000000d80b7 R15: 00000000cf392011 [ 768.950700][ C0] ? _sha256_update+0x1d2/0x200 [ 768.955550][ C0] ? done_hash+0x12/0x12 [ 768.959799][ C0] sha256_avx2_update+0x2d/0x40 [ 768.964713][ C0] crypto_shash_update+0xc9/0x120 [ 768.969787][ C0] ima_calc_file_hash_tfm+0x321/0x3e0 [ 768.975172][ C0] ? ima_calc_field_array_hash_tfm.isra.0+0x540/0x540 [ 768.981930][ C0] ? __kasan_check_read+0x11/0x20 [ 768.986959][ C0] ? mark_held_locks+0xa4/0xf0 [ 768.991725][ C0] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 768.997180][ C0] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 769.002635][ C0] ? lockdep_hardirqs_on+0x421/0x5e0 [ 769.007944][ C0] ? retint_kernel+0x2b/0x2b [ 769.012534][ C0] ? trace_hardirqs_on_caller+0x6a/0x240 [ 769.018165][ C0] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 769.023758][ C0] ? __this_cpu_preempt_check+0x8a/0x190 [ 769.029391][ C0] ? __this_cpu_preempt_check+0x35/0x190 [ 769.035022][ C0] ? retint_kernel+0x2b/0x2b [ 769.039617][ C0] ? ima_calc_file_hash+0x18a/0x570 [ 769.044828][ C0] ima_calc_file_hash+0x1aa/0x570 [ 769.049852][ C0] ima_collect_measurement+0x534/0x5f0 [ 769.055311][ C0] ? ima_get_action+0xa0/0xa0 [ 769.059987][ C0] ? ima_get_hash_algo+0x6d/0x360 [ 769.065111][ C0] process_measurement+0xd45/0x1850 [ 769.070317][ C0] ? mmap_violation_check+0x200/0x200 [ 769.075691][ C0] ? __this_cpu_preempt_check+0x8a/0x190 [ 769.081325][ C0] ? __this_cpu_preempt_check+0x35/0x190 [ 769.086968][ C0] ? retint_kernel+0x2b/0x2b [ 769.091666][ C0] ? aa_get_task_label+0x3a6/0x710 [ 769.096789][ C0] ? lock_release+0x4c0/0x960 [ 769.101481][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 769.107725][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 769.113964][ C0] ? refcount_sub_and_test_checked+0x154/0x200 [ 769.120131][ C0] ? refcount_dec_not_one+0x1f0/0x1f0 [ 769.125513][ C0] ? refcount_dec_and_test_checked+0x1b/0x20 [ 769.131489][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 769.137726][ C0] ? apparmor_task_getsecid+0x94/0xd0 [ 769.143111][ C0] ima_file_check+0xc5/0x110 [ 769.147703][ C0] ? process_measurement+0x1850/0x1850 [ 769.153174][ C0] path_openat+0x113d/0x4710 [ 769.157765][ C0] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 769.163226][ C0] ? lockdep_hardirqs_on+0x421/0x5e0 [ 769.168513][ C0] ? retint_kernel+0x2b/0x2b [ 769.173110][ C0] ? path_lookupat.isra.0+0x8d0/0x8d0 [ 769.178477][ C0] ? retint_kernel+0x2b/0x2b [ 769.183075][ C0] do_filp_open+0x1a1/0x280 [ 769.187594][ C0] ? may_open_dev+0x100/0x100 [ 769.192288][ C0] ? do_raw_spin_unlock+0x178/0x270 [ 769.197487][ C0] ? _raw_spin_unlock+0x28/0x40 [ 769.202334][ C0] ? __alloc_fd+0x487/0x620 [ 769.206845][ C0] do_sys_open+0x3fe/0x5d0 [ 769.211282][ C0] ? filp_open+0x80/0x80 [ 769.215532][ C0] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 769.220987][ C0] ? do_syscall_64+0x26/0x790 [ 769.225660][ C0] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 769.231723][ C0] ? do_syscall_64+0x26/0x790 [ 769.236409][ C0] __x64_sys_open+0x7e/0xc0 [ 769.240913][ C0] do_syscall_64+0xfa/0x790 [ 769.245413][ C0] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 769.251295][ C0] RIP: 0033:0x447709 [ 769.255191][ C0] Code: e8 3c e6 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 ab 06 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 769.274794][ C0] RSP: 002b:00007fce7ac54db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 [ 769.283203][ C0] RAX: ffffffffffffffda RBX: 00000000006ddc28 RCX: 0000000000447709 [ 769.291170][ C0] RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000100 [ 769.299148][ C0] RBP: 00000000006ddc20 R08: 0000000000000000 R09: 0000000000000000 [ 769.307126][ C0] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc2c [ 769.315093][ C0] R13: 00007ffd0e67ecaf R14: 00007fce7ac559c0 R15: 0000000000000000 [ 769.323087][ C0] rcu: rcu_preempt kthread starved for 10502 jiffies! g7137 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 [ 769.334173][ C0] rcu: RCU grace-period kthread stack dump: [ 769.340313][ C0] rcu_preempt R running task 29272 10 2 0x80004000 [ 769.348205][ C0] Call Trace: [ 769.351497][ C0] __schedule+0x8e1/0x1f30 [ 769.355915][ C0] ? __sched_text_start+0x8/0x8 [ 769.360764][ C0] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 769.366562][ C0] ? schedule_timeout+0x47c/0xc50 [ 769.371583][ C0] ? lockdep_hardirqs_on+0x421/0x5e0 [ 769.376865][ C0] schedule+0xdc/0x2b0 [ 769.380929][ C0] schedule_timeout+0x486/0xc50 [ 769.385773][ C0] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 769.391579][ C0] ? usleep_range+0x170/0x170 [ 769.396253][ C0] ? trace_hardirqs_on+0x67/0x240 [ 769.401297][ C0] ? __next_timer_interrupt+0x1a0/0x1a0 [ 769.406842][ C0] ? swake_up_one+0x60/0x60 [ 769.411358][ C0] rcu_gp_kthread+0x9b2/0x18d0 [ 769.416139][ C0] ? rcu_barrier+0x350/0x350 [ 769.420727][ C0] ? trace_hardirqs_on+0x67/0x240 [ 769.425759][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 769.431993][ C0] ? __kthread_parkme+0x108/0x1c0 [ 769.437011][ C0] ? __kasan_check_read+0x11/0x20 [ 769.442037][ C0] kthread+0x361/0x430 [ 769.446099][ C0] ? rcu_barrier+0x350/0x350 [ 769.450681][ C0] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 769.456407][ C0] ret_from_fork+0x24/0x30