INFO: task syz-executor.0:16472 blocked for more than 143 seconds. Not tainted 5.12.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28128 pid:16472 ppid: 12635 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0x916/0x23e0 kernel/sched/core.c:5147 schedule+0xcf/0x270 kernel/sched/core.c:5226 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 bcm_release+0x94/0x780 net/can/bcm.c:1474 __sock_release+0xcd/0x280 net/socket.c:599 sock_close+0x18/0x20 net/socket.c:1258 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbfc/0x2a60 kernel/exit.c:826 do_group_exit+0x125/0x310 kernel/exit.c:923 get_signal+0x47f/0x2150 kernel/signal.c:2818 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x171/0x280 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007fe0a7604188 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000003 RBX: 000000000056c008 RCX: 00000000004665f9 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffd720be6ef R14: 00007fe0a7604300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1641: #0: ffffffff8bf79760 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333 2 locks held by systemd-journal/4852: #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1334 [inline] #0: ffff8880b9d35258 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x21c/0x23e0 kernel/sched/core.c:5061 #1: ffffffff8c0b5300 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: nd_jump_root+0x3c7/0x570 fs/namei.c:933 1 lock held by in:imklog/8124: #0: ffff88801d01cd70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 3 locks held by kworker/u4:3/26651: #0: ffff88814016a938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88814016a938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88814016a938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88814016a938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88814016a938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88814016a938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc9001757fda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d6914d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:557 2 locks held by syz-executor.0/16472: #0: ffff8880324b3690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #0: ffff8880324b3690 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:598 #1: ffffffff8d6914d0 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 1 lock held by syz-executor.0/16772: #0: ffffffff8d6914d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1641 Comm: khungtaskd Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4852 Comm: systemd-journal Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_preemption_disabled+0x41/0x150 lib/smp_processor_id.c:60 Code: 9d 99 eb 76 65 8b 1d ee f3 eb 76 81 e3 ff ff ff 7f 31 ff 89 de 0f 1f 44 00 00 85 db 74 11 0f 1f 44 00 00 44 89 e0 5b 5d 41 5c <41> 5d 41 5e c3 0f 1f 44 00 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 RSP: 0018:ffffc90000edf998 EFLAGS: 00000002 RAX: 0000000000000001 RBX: ffffffff8dc98c2c RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 1ffff920001dbf38 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 000000000000003f R12: ffffffff90916a90 R13: ffffffff896bb500 R14: ffff88802d13b880 R15: dffffc0000000000 FS: 00007f1e5435a8c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1e50e495a0 CR3: 000000002d3a2000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:433 [inline] lock_release+0x15a/0x720 kernel/locking/lockdep.c:5531 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:191 __debug_check_no_obj_freed lib/debugobjects.c:997 [inline] debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1018 slab_free_hook mm/slub.c:1556 [inline] slab_free_freelist_hook+0x174/0x240 mm/slub.c:1606 slab_free mm/slub.c:3166 [inline] kmem_cache_free+0x8a/0x740 mm/slub.c:3182 putname+0xe1/0x120 fs/namei.c:259 filename_parentat+0x4c3/0x570 fs/namei.c:2505 filename_create+0x9e/0x490 fs/namei.c:3575 user_path_create fs/namei.c:3650 [inline] do_mkdirat+0xa0/0x310 fs/namei.c:3828 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1e53615687 Code: 00 b8 ff ff ff ff c3 0f 1f 40 00 48 8b 05 09 d8 2b 00 64 c7 00 5f 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 d7 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffd2f4dd598 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffd2f4e0600 RCX: 00007f1e53615687 RDX: 0000000000000000 RSI: 00000000000001ed RDI: 000055d22a9818a0 RBP: 00007ffd2f4dd5d0 R08: 000055d228f203e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 000055d22a9818a0 R15: 00007ffd2f4ddc10