INFO: task kworker/u4:6:23443 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/u4:6 D25872 23443 2 0x80004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 hashlimit_proc_net_exit net/netfilter/xt_hashlimit.c:1267 [inline] hashlimit_net_exit+0x16d/0x3d0 net/netfilter/xt_hashlimit.c:1290 ops_exit_list.isra.0+0xb1/0x160 net/core/net_namespace.c:172 cleanup_net+0x538/0xaf0 net/core/net_namespace.c:597 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.2:1374 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. syz-executor.2 D27392 1374 1353 0x20024004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 hashlimit_mt_check_common.isra.0+0x341/0x1500 net/netfilter/xt_hashlimit.c:903 hashlimit_mt_check+0xa4/0xd0 net/netfilter/xt_hashlimit.c:963 xt_check_match+0x280/0x690 net/netfilter/x_tables.c:501 check_match net/ipv4/netfilter/ip_tables.c:472 [inline] find_check_match net/ipv4/netfilter/ip_tables.c:488 [inline] find_check_entry.isra.0+0x32f/0x920 net/ipv4/netfilter/ip_tables.c:538 translate_table+0xcb4/0x17d0 net/ipv4/netfilter/ip_tables.c:717 translate_compat_table+0xb60/0x1820 net/ipv4/netfilter/ip_tables.c:1465 compat_do_replace.isra.0+0x1b7/0x3c0 net/ipv6/netfilter/ip6_tables.c:1528 compat_do_ipt_set_ctl+0x128/0x170 net/ipv4/netfilter/ip_tables.c:1548 compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline] compat_nf_setsockopt+0x98/0x140 net/netfilter/nf_sockopt.c:156 compat_ip_setsockopt net/ipv4/ip_sockglue.c:1286 [inline] compat_ip_setsockopt+0x106/0x140 net/ipv4/ip_sockglue.c:1267 inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1045 compat_tcp_setsockopt+0x4d/0x80 net/ipv4/tcp.c:3169 compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:3160 __compat_sys_setsockopt+0x185/0x380 net/compat.c:384 __do_compat_sys_setsockopt net/compat.c:397 [inline] __se_compat_sys_setsockopt net/compat.c:394 [inline] __ia32_compat_sys_setsockopt+0xbd/0x150 net/compat.c:394 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline] do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fe39a9 Code: Bad RIP value. RSP: 002b:00000000f5ddf0cc EFLAGS: 00000296 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000040 RSI: 0000000020000bc0 RDI: 0000000000000388 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor.4:1377 blocked for more than 144 seconds. Not tainted 5.5.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28272 1377 1352 0x20024004 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4081 schedule+0xdc/0x2b0 kernel/sched/core.c:4155 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4214 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 hashlimit_mt_check_common.isra.0+0x341/0x1500 net/netfilter/xt_hashlimit.c:903 hashlimit_mt_check+0xa4/0xd0 net/netfilter/xt_hashlimit.c:963 xt_check_match+0x280/0x690 net/netfilter/x_tables.c:501 check_match net/ipv4/netfilter/ip_tables.c:472 [inline] find_check_match net/ipv4/netfilter/ip_tables.c:488 [inline] find_check_entry.isra.0+0x32f/0x920 net/ipv4/netfilter/ip_tables.c:538 translate_table+0xcb4/0x17d0 net/ipv4/netfilter/ip_tables.c:717 translate_compat_table+0xb60/0x1820 net/ipv4/netfilter/ip_tables.c:1465 compat_do_replace.isra.0+0x1b7/0x3c0 net/ipv6/netfilter/ip6_tables.c:1528 compat_do_ipt_set_ctl+0x128/0x170 net/ipv4/netfilter/ip_tables.c:1548 compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline] compat_nf_setsockopt+0x98/0x140 net/netfilter/nf_sockopt.c:156 compat_ip_setsockopt net/ipv4/ip_sockglue.c:1286 [inline] compat_ip_setsockopt+0x106/0x140 net/ipv4/ip_sockglue.c:1267 inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1045 compat_tcp_setsockopt+0x4d/0x80 net/ipv4/tcp.c:3169 compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:3160 __compat_sys_setsockopt+0x185/0x380 net/compat.c:384 __do_compat_sys_setsockopt net/compat.c:397 [inline] __se_compat_sys_setsockopt net/compat.c:394 [inline] __ia32_compat_sys_setsockopt+0xbd/0x150 net/compat.c:394 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline] do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7f089a9 Code: Bad RIP value. RSP: 002b:00000000f5d040cc EFLAGS: 00000296 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000040 RSI: 0000000020000bc0 RDI: 0000000000000388 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1108: #0: ffffffff899a1140 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5333 1 lock held by rsyslogd/9544: #0: ffff88809f6eb5e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9634: #0: ffff888093527090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017bb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9635: #0: ffff88809c683090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017fb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9636: #0: ffff888096c6d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000180b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9637: #0: ffff88809e9f4090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000178b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9638: #0: ffff8880a22f7090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000181b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9639: #0: ffff88809e7fa090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017ab2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9640: #0: ffff8880a7f2e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000175b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 4 locks held by kworker/u4:6/23443: #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff88821b78e528 ((wq_completion)netns){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2235 #1: ffffc90001847dc0 (net_cleanup_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239 #2: ffffffff8a4ba8c8 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0xaf0 net/core/net_namespace.c:559 #3: ffffffff8a544840 (hashlimit_mutex){+.+.}, at: hashlimit_proc_net_exit net/netfilter/xt_hashlimit.c:1267 [inline] #3: ffffffff8a544840 (hashlimit_mutex){+.+.}, at: hashlimit_net_exit+0x16d/0x3d0 net/netfilter/xt_hashlimit.c:1290 1 lock held by syz-executor.3/1371: 1 lock held by syz-executor.2/1374: #0: ffffffff8a544840 (hashlimit_mutex){+.+.}, at: hashlimit_mt_check_common.isra.0+0x341/0x1500 net/netfilter/xt_hashlimit.c:903 1 lock held by syz-executor.4/1377: #0: ffffffff8a544840 (hashlimit_mutex){+.+.}, at: hashlimit_mt_check_common.isra.0+0x341/0x1500 net/netfilter/xt_hashlimit.c:903 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1108 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+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb11/0x10c0 kernel/hung_task.c:289 kthread+0x361/0x430 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: 1371 Comm: syz-executor.3 Not tainted 5.5.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:mark_usage kernel/locking/lockdep.c:3564 [inline] RIP: 0010:__lock_acquire+0x467/0x4a00 kernel/locking/lockdep.c:3908 Code: 08 84 c0 0f 85 a0 35 00 00 45 84 f6 41 0f b6 42 22 78 2c a8 03 41 8b 93 64 08 00 00 0f 85 53 0e 00 00 85 d2 0f 85 9a 19 00 00 <45> 8b b3 84 08 00 00 45 85 f6 0f 85 f9 19 00 00 41 0f b6 42 22 a8 RSP: 0018:ffffc90001cb7450 EFLAGS: 00000046 RAX: 0000000000000004 RBX: 0000000000000000 RCX: 0000000000040000 RDX: 0000000000000000 RSI: 0000000000000a3b RDI: ffff8880666c8e21 RBP: ffffc90001cb7568 R08: 0000000000000001 R09: 0000000000000a3b R10: ffff8880666c8e00 R11: ffff8880666c8540 R12: 0000000000000a3b R13: ffff8880666c8e22 R14: 000000000000000a R15: 0000000000040a3b FS: 0000000000000000(0000) GS:ffff8880ae900000(0063) knlGS:00000000f5df4b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f7fe397f CR3: 00000000517ab000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4484 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:343 [inline] htable_selective_cleanup+0xa6/0x330 net/netfilter/xt_hashlimit.c:382 htable_destroy net/netfilter/xt_hashlimit.c:422 [inline] htable_put+0x176/0x220 net/netfilter/xt_hashlimit.c:449 hashlimit_mt_destroy+0x56/0x70 net/netfilter/xt_hashlimit.c:985 cleanup_match+0xde/0x170 net/ipv6/netfilter/ip6_tables.c:478 cleanup_entry+0xd7/0x270 net/ipv4/netfilter/ip_tables.c:645 translate_table+0xd86/0x17d0 net/ipv4/netfilter/ip_tables.c:728 translate_compat_table+0xb60/0x1820 net/ipv4/netfilter/ip_tables.c:1465 compat_do_replace.isra.0+0x1b7/0x3c0 net/ipv6/netfilter/ip6_tables.c:1528 compat_do_ipt_set_ctl+0x128/0x170 net/ipv4/netfilter/ip_tables.c:1548 compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline] compat_nf_setsockopt+0x98/0x140 net/netfilter/nf_sockopt.c:156 compat_ip_setsockopt net/ipv4/ip_sockglue.c:1286 [inline] compat_ip_setsockopt+0x106/0x140 net/ipv4/ip_sockglue.c:1267 inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1045 compat_tcp_setsockopt+0x4d/0x80 net/ipv4/tcp.c:3169 compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:3160 __compat_sys_setsockopt+0x185/0x380 net/compat.c:384 __do_compat_sys_setsockopt net/compat.c:397 [inline] __se_compat_sys_setsockopt net/compat.c:394 [inline] __ia32_compat_sys_setsockopt+0xbd/0x150 net/compat.c:394 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline] do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7ff89a9 Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f5df40cc EFLAGS: 00000296 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000040 RSI: 0000000020000bc0 RDI: 0000000000000388 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000