INFO: task syz-executor.4:32126 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D26136 32126 8159 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 xlog_grant_head_wait+0x13b/0xcd0 fs/xfs/xfs_log.c:263 xlog_grant_head_check+0x3c8/0x420 fs/xfs/xfs_log.c:325 xfs_log_reserve+0x347/0xa70 fs/xfs/xfs_log.c:454 xfs_trans_reserve+0x63a/0x9c0 fs/xfs/xfs_trans.c:197 xfs_trans_alloc+0x2f7/0x700 fs/xfs/xfs_trans.c:289 xlog_finish_defer_ops fs/xfs/xfs_log_recover.c:4841 [inline] xlog_recover_process_intents+0x274/0x430 fs/xfs/xfs_log_recover.c:4947 xlog_recover_finish+0x5f/0x230 fs/xfs/xfs_log_recover.c:5839 xfs_log_mount_finish+0x135/0x450 fs/xfs/xfs_log.c:778 xfs_mountfs+0x1032/0x1bf0 fs/xfs/xfs_mount.c:974 xfs_fs_fill_super+0xd0e/0x1540 fs/xfs/xfs_super.c:1720 mount_bdev+0x2fc/0x3b0 fs/super.c:1158 mount_fs+0xa3/0x310 fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2492 [inline] do_mount+0x115c/0x2f50 fs/namespace.c:2822 ksys_mount+0xcf/0x130 fs/namespace.c:3038 __do_sys_mount fs/namespace.c:3052 [inline] __se_sys_mount fs/namespace.c:3049 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3049 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7ff5f612f5da Code: Bad RIP value. RSP: 002b:00007ff5f469ff88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000000baed RCX: 00007ff5f612f5da RDX: 000000002000bb00 RSI: 0000000020000040 RDI: 00007ff5f469ffe0 RBP: 00007ff5f46a0020 R08: 00007ff5f46a0020 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000000002000bb00 R13: 0000000020000040 R14: 00007ff5f469ffe0 R15: 00000000200002c0 Showing all locks held in the system: 1 lock held by khungtaskd/1571: #0: 00000000499b9db0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7810: #0: 0000000043e87169 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by agetty/8034: #0: 0000000014e30e62 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000d7953766 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154 4 locks held by kworker/u4:6/9519: #0: 00000000d381e325 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000003ee287d9 (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 0000000036ecab2d (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:521 #3: 000000007dda30ba (rcu_preempt_state.barrier_mutex){+.+.}, at: _rcu_barrier+0x59/0x3e0 kernel/rcu/tree.c:3430 2 locks held by syz-executor.4/32126: #0: 0000000005a4266b (&type->s_umount_key#69/1){+.+.}, at: alloc_super fs/super.c:226 [inline] #0: 0000000005a4266b (&type->s_umount_key#69/1){+.+.}, at: sget_userns+0x20b/0xcd0 fs/super.c:519 #1: 00000000c79e0393 (sb_internal#3){.+.+}, at: sb_start_intwrite include/linux/fs.h:1626 [inline] #1: 00000000c79e0393 (sb_internal#3){.+.+}, at: xfs_trans_alloc+0x4fc/0x700 fs/xfs/xfs_trans.c:271 1 lock held by syz-executor.0/7117: #0: 0000000005a4266b (&type->s_umount_key#88){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 1 lock held by syz-executor.0/7118: #0: 0000000005a4266b (&type->s_umount_key#88){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 1 lock held by syz-executor.0/7119: #0: 0000000005a4266b (&type->s_umount_key#88){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 1 lock held by syz-executor.0/7120: #0: 0000000005a4266b (&type->s_umount_key#88){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 1 lock held by syz-executor.0/7121: #0: 0000000005a4266b (&type->s_umount_key#88){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 1 lock held by syz-executor.0/7122: #0: 0000000005a4266b (&type->s_umount_key#88){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9519 Comm: kworker/u4:6 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: netns cleanup_net RIP: 0010:trace_softirqs_on+0x283/0x3b0 kernel/locking/lockdep.c:2954 Code: 00 85 c0 75 49 65 48 8b 1c 25 c0 df 01 00 48 8d bb 84 08 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 e0 00 00 00 c7 RSP: 0018:ffff88803eea7720 EFLAGS: 00000803 RAX: dffffc0000000000 RBX: ffff88803ee98500 RCX: 1ffffffff1a486ec RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88803ee98d84 RBP: ffff88803ee98500 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000000 R12: ffff88803ee98500 R13: 00000000000003f4 R14: 0000000000000003 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff5f612f5b0 CR3: 00000000aee4d000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __local_bh_enable_ip+0x1cc/0x270 kernel/softirq.c:177 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:1907 [inline] nf_ct_iterate_cleanup+0x239/0x520 net/netfilter/nf_conntrack_core.c:1930 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2015 [inline] nf_ct_iterate_cleanup_net+0x113/0x170 net/netfilter/nf_conntrack_core.c:2000 masq_device_event+0xae/0xe0 net/ipv6/netfilter/nf_nat_masquerade_ipv6.c:77 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93 call_netdevice_notifiers net/core/dev.c:1762 [inline] dev_close_many+0x323/0x670 net/core/dev.c:1514 rollback_registered_many+0x2f7/0xe70 net/core/dev.c:8173 unregister_netdevice_many.part.0+0x1a/0x300 net/core/dev.c:9324 unregister_netdevice_many+0x36/0x50 net/core/dev.c:9323 vti6_exit_batch_net+0x40f/0x620 net/ipv6/ip6_vti.c:1178 ops_exit_list+0xf9/0x150 net/core/net_namespace.c:156 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:554 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415