INFO: task syz-executor.4:18719 blocked for more than 143 seconds. Not tainted 5.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27912 18719 9589 0x00004004 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 htable_put+0x21/0x220 net/netfilter/xt_hashlimit.c:446 hashlimit_mt_destroy_v2+0x56/0x70 net/netfilter/xt_hashlimit.c:971 cleanup_match+0xde/0x170 net/ipv6/netfilter/ip6_tables.c:478 cleanup_entry+0xf5/0x2a0 net/ipv6/netfilter/ip6_tables.c:662 do_replace net/ipv6/netfilter/ip6_tables.c:1165 [inline] do_ip6t_set_ctl+0x3e7/0x4c8 net/ipv6/netfilter/ip6_tables.c:1681 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x77/0xd0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt net/ipv6/ipv6_sockglue.c:949 [inline] ipv6_setsockopt+0x13e/0x170 net/ipv6/ipv6_sockglue.c:933 tcp_setsockopt net/ipv4/tcp.c:3158 [inline] tcp_setsockopt+0x8f/0xe0 net/ipv4/tcp.c:3152 sock_common_setsockopt+0x94/0xd0 net/core/sock.c:3149 __sys_setsockopt+0x261/0x4c0 net/socket.c:2117 __do_sys_setsockopt net/socket.c:2133 [inline] __se_sys_setsockopt net/socket.c:2130 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2130 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45aff9 Code: Bad RIP value. RSP: 002b:00007f1b8a685c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f1b8a6866d4 RCX: 000000000045aff9 RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000488 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009c1 R14: 00000000004d3820 R15: 000000000075bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1128: #0: ffffffff899a3f00 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5334 1 lock held by rsyslogd/9446: #0: ffff888098189420 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9536: #0: ffff88809f96d090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900061152e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9537: #0: ffff88809e21f090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900060d32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9538: #0: ffff88809878e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900060ff2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9539: #0: ffff888095472090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900061332e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9540: #0: ffff88809dd5c090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900060b32e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9541: #0: ffff888097ac3090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900061232e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/9542: #0: ffff888093f37090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900060932e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by kworker/0:1/19520: 1 lock held by syz-executor.2/18714: 1 lock held by syz-executor.4/18719: #0: ffffffff8a5500c0 (hashlimit_mutex){+.+.}, at: htable_put+0x21/0x220 net/netfilter/xt_hashlimit.c:446 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1128 Comm: khungtaskd Not tainted 5.5.0-rc6-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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18714 Comm: syz-executor.2 Not tainted 5.5.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:match_held_lock+0x0/0x510 kernel/locking/lockdep.c:4014 Code: 08 48 c7 c2 10 d7 59 81 4c 89 ce e8 ba fa ff ff 85 c0 78 02 c9 c3 89 c7 89 45 fc e8 8a e6 ff ff 8b 45 fc c9 c3 0f 1f 44 00 00 <48> b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 57 41 56 41 55 41 54 RSP: 0018:ffffc900050278f8 EFLAGS: 00000002 RAX: 0000000000000000 RBX: ffff88809175c2c0 RCX: ffff88809175cb58 RDX: 1ffff110122eb96a RSI: ffffffff899a3ec0 RDI: ffff88809175cb58 RBP: ffffc90005027948 R08: 1ffffffff165e7c2 R09: fffffbfff165e7c3 R10: fffffbfff165e7c2 R11: ffffffff8b2f3e17 R12: ffffed10122eb96a R13: ffff88809175cb58 R14: ffffffff899a3ec0 R15: 0000000000000000 FS: 00007f98dd9f9700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000092a28000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:361 [inline] ___might_sleep+0x242/0x2c0 kernel/sched/core.c:6765 htable_selective_cleanup+0x22c/0x330 net/netfilter/xt_hashlimit.c:388 htable_destroy net/netfilter/xt_hashlimit.c:422 [inline] htable_put+0x176/0x220 net/netfilter/xt_hashlimit.c:449 hashlimit_mt_destroy_v2+0x56/0x70 net/netfilter/xt_hashlimit.c:971 cleanup_match+0xde/0x170 net/ipv6/netfilter/ip6_tables.c:478 cleanup_entry+0xf5/0x2a0 net/ipv6/netfilter/ip6_tables.c:662 do_replace net/ipv6/netfilter/ip6_tables.c:1165 [inline] do_ip6t_set_ctl+0x3e7/0x4c8 net/ipv6/netfilter/ip6_tables.c:1681 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x77/0xd0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt net/ipv6/ipv6_sockglue.c:949 [inline] ipv6_setsockopt+0x13e/0x170 net/ipv6/ipv6_sockglue.c:933 tcp_setsockopt net/ipv4/tcp.c:3158 [inline] tcp_setsockopt+0x8f/0xe0 net/ipv4/tcp.c:3152 sock_common_setsockopt+0x94/0xd0 net/core/sock.c:3149 __sys_setsockopt+0x261/0x4c0 net/socket.c:2117 __do_sys_setsockopt net/socket.c:2133 [inline] __se_sys_setsockopt net/socket.c:2130 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:2130 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45aff9 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f98dd9f8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f98dd9f96d4 RCX: 000000000045aff9 RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000488 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009c1 R14: 00000000004d3820 R15: 000000000075bf2c