INFO: task kworker/u4:2:29017 blocked for more than 143 seconds. Not tainted 5.5.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D23904 29017 2 0x80004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x87f/0xcd0 kernel/sched/core.c:4081 schedule+0x188/0x210 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common+0x11f1/0x2f30 kernel/locking/mutex.c:1033 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118 hashlimit_proc_net_exit net/netfilter/xt_hashlimit.c:1267 [inline] hashlimit_net_exit+0x40/0x210 net/netfilter/xt_hashlimit.c:1290 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x6f8/0xb80 net/core/net_namespace.c:597 process_one_work+0x7f5/0x10d0 kernel/workqueue.c:2264 worker_thread+0xbbc/0x1630 kernel/workqueue.c:2410 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 1 lock held by khungtaskd/899: #0: ffffffff890d45c0 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30 include/linux/rcupdate.h:207 3 locks held by rs:main Q:Reg/8587: #0: ffff8880a7473ae0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x243/0x2e0 fs/file.c:801 #1: ffff88821446e428 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2885 [inline] #1: ffff88821446e428 (sb_writers#3){.+.+}, at: vfs_write+0x24e/0x580 fs/read_write.c:557 #2: ffff888218791038 (&(&virtscsi_vq->vq_lock)->rlock){-.-.}, at: virtscsi_add_cmd+0x53/0x580 drivers/scsi/virtio_scsi.c:480 1 lock held by rsyslogd/8589: #0: ffff88809e6e6de0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x243/0x2e0 fs/file.c:801 2 locks held by getty/8679: #0: ffff888097b43090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900019b32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8680: #0: ffff888098c0a090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900019732e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8681: #0: ffff88809f78d090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc9000191f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8682: #0: ffff8880a8c34090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900019632e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8683: #0: ffff8880a00e0090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900019c32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8684: #0: ffff88808bd13090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900019a32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8685: #0: ffff88809ec08090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900019132e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 4 locks held by kworker/u4:2/29017: #0: ffff8880a9e85928 ((wq_completion)netns){+.+.}, at: spin_unlock_irq include/linux/spinlock.h:388 [inline] #0: ffff8880a9e85928 ((wq_completion)netns){+.+.}, at: process_one_work+0x763/0x10d0 kernel/workqueue.c:2237 #1: ffffc90001c6fd78 (net_cleanup_work){+.+.}, at: process_one_work+0x7a5/0x10d0 kernel/workqueue.c:2239 #2: ffffffff89354aa8 (pernet_ops_rwsem){++++}, at: cleanup_net+0xa5/0xb80 net/core/net_namespace.c:559 #3: ffffffff893710f0 (hashlimit_mutex){+.+.}, at: hashlimit_proc_net_exit net/netfilter/xt_hashlimit.c:1267 [inline] #3: ffffffff893710f0 (hashlimit_mutex){+.+.}, at: hashlimit_net_exit+0x40/0x210 net/netfilter/xt_hashlimit.c:1290 1 lock held by syz-executor.1/14219: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 899 Comm: khungtaskd Not tainted 5.5.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaa/0x190 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x16f/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xd40/0xd60 kernel/hung_task.c:289 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 14219 Comm: syz-executor.1 Not tainted 5.5.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:28 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:135 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:166 [inline] RIP: 0010:check_memory_region_inline mm/kasan/generic.c:182 [inline] RIP: 0010:check_memory_region+0x2e/0x2f0 mm/kasan/generic.c:192 Code: 41 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 09 02 00 00 48 89 fb 48 c1 eb 2f 81 fb fe ff 01 00 0f 86 83 02 00 00 49 89 fc <49> c1 ec 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 04 4c 8d 54 37 RSP: 0018:ffffc9000288f818 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 000000000001ffff RCX: ffffffff815bda87 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff89e67a20 RBP: ffffc9000288f840 R08: ffff8880960941c0 R09: fffff520032cba0a R10: fffff520032cba0a R11: 0000000000000000 R12: ffffffff89e67a20 R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000004 FS: 00007f40e5d28700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000422d10 CR3: 00000000950b4000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __kasan_check_read+0x11/0x20 mm/kasan/common.c:95 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] hlock_class kernel/locking/lockdep.c:163 [inline] mark_lock+0x107/0x1650 kernel/locking/lockdep.c:3642 mark_held_locks kernel/locking/lockdep.c:3359 [inline] __trace_hardirqs_on_caller kernel/locking/lockdep.c:3380 [inline] lockdep_hardirqs_on+0x205/0x7a0 kernel/locking/lockdep.c:3433 trace_hardirqs_on+0x74/0x80 kernel/trace/trace_preemptirq.c:31 __local_bh_enable_ip+0x13a/0x240 kernel/softirq.c:194 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0x2f/0x40 kernel/locking/spinlock.c:207 spin_unlock_bh include/linux/spinlock.h:383 [inline] htable_selective_cleanup net/netfilter/xt_hashlimit.c:387 [inline] htable_destroy net/netfilter/xt_hashlimit.c:422 [inline] htable_put+0x4f8/0x620 net/netfilter/xt_hashlimit.c:449 hashlimit_mt_destroy+0x5b/0x70 net/netfilter/xt_hashlimit.c:985 cleanup_match net/ipv4/netfilter/ip_tables.c:460 [inline] find_check_entry net/ipv4/netfilter/ip_tables.c:564 [inline] translate_table+0x1b2b/0x2230 net/ipv4/netfilter/ip_tables.c:717 do_replace net/ipv4/netfilter/ip_tables.c:1136 [inline] do_ipt_set_ctl+0x2c3/0x550 net/ipv4/netfilter/ip_tables.c:1672 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x27a/0x2a0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0xd8/0xf0 net/ipv4/ip_sockglue.c:1260 tcp_setsockopt+0xbe/0xd0 net/ipv4/tcp.c:3158 sock_common_setsockopt+0x99/0xb0 net/core/sock.c:3149 __sys_setsockopt+0x582/0x720 net/socket.c:2117 __do_sys_setsockopt net/socket.c:2133 [inline] __se_sys_setsockopt net/socket.c:2130 [inline] __x64_sys_setsockopt+0xbf/0xd0 net/socket.c:2130 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b349 Code: Bad RIP value. RSP: 002b:00007f40e5d27c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f40e5d286d4 RCX: 000000000045b349 RDX: 0000000000000040 RSI: 0004000000000000 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 00000000000003a0 R09: 0000000000000000 R10: 0000000020000440 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009fc R14: 00000000004cb5e1 R15: 000000000075bf2c