INFO: task syz-executor.2:31052 blocked for more than 143 seconds. Not tainted 5.7.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D27704 31052 7076 0x80004006 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8f3/0x1f90 kernel/sched/core.c:4156 schedule+0xd0/0x2a0 kernel/sched/core.c:4231 rwsem_down_write_slowpath+0x706/0xf90 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1844 bcm_release+0x8b/0x660 net/can/bcm.c:1474 __sock_release+0xcd/0x280 net/socket.c:605 sock_close+0x18/0x20 net/socket.c:1278 __fput+0x33e/0x880 fs/file_table.c:281 task_work_run+0xf4/0x1b0 kernel/task_work.c:123 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xb3f/0x2de0 kernel/exit.c:806 do_group_exit+0x125/0x340 kernel/exit.c:904 get_signal+0x47b/0x24e0 kernel/signal.c:2739 do_signal+0x81/0x2240 arch/x86/kernel/signal.c:810 exit_to_usermode_loop+0x26c/0x360 arch/x86/entry/common.c:161 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45ca59 Code: Bad RIP value. RSP: 002b:00007ff34f1dfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000004 RBX: 00000000005078e0 RCX: 000000000045ca59 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000b99 R14: 00000000004cdf85 R15: 00007ff34f1e06d4 Showing all locks held in the system: 3 locks held by kworker/u4:0/7: #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:279 [inline] #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff88821b039138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2239 #1: ffffc90000cdfdc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 #2: ffffffff8a586130 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 1 lock held by khungtaskd/1146: #0: ffffffff899be040 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6504: #0: ffff88809a5d18f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 3 locks held by kworker/u4:7/8404: #0: ffff8880ae737d58 (&rq->lock){-.-.}-{2:2}, at: newidle_balance+0x9ce/0xdd0 kernel/sched/fair.c:10525 #1: ffffffff899be040 (rcu_read_lock){....}-{1:2}, at: __update_idle_core+0x42/0x3e0 kernel/sched/fair.c:6002 #2: ffff8880ae727598 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x55/0x1a0 kernel/time/timer.c:935 2 locks held by syz-executor.2/31052: #0: ffff888027544c90 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline] #0: ffff888027544c90 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:604 #1: ffffffff8a586130 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1844 1 lock held by syz-executor.2/31374: #0: ffffffff8a586130 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x270/0x590 net/core/net_namespace.c:478 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1146 Comm: khungtaskd Not tainted 5.7.0-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa8c/0x1010 kernel/hung_task.c:289 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3866 Comm: systemd-journal Not tainted 5.7.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:958 [inline] RIP: 0010:debug_check_no_obj_freed+0x107/0x449 lib/debugobjects.c:998 Code: 10 4c 8b 38 4d 85 ff 0f 84 26 02 00 00 31 ed 4c 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 2d 02 00 00 49 8d 7f 18 83 c5 01 4d 8b 27 <48> 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 29 02 00 00 4d 8b 77 18 4c RSP: 0018:ffffc900015f7cc8 EFLAGS: 00000002 RAX: 1ffff1100761df6c RBX: dffffc0000000000 RCX: ffffffff815ac5c9 RDX: 1ffffffff191a45f RSI: 0000000000000082 RDI: ffff88803b0efb78 RBP: 0000000000000001 R08: 0000000000000004 R09: fffff520002bef88 R10: 0000000000000003 R11: fffff520002bef87 R12: ffff888095430038 R13: ffffffff8c8d22e8 R14: 1ffffffff191a45c R15: ffff88803b0efb60 FS: 00007feb4343c8c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb409a1000 CR3: 00000000949dd000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kmem_cache_free+0x185/0x320 mm/slab.c:3693 putname+0xe1/0x120 fs/namei.c:259 do_sys_openat2+0x467/0x7d0 fs/open.c:1188 do_sys_open+0xc3/0x140 fs/open.c:1195 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x7feb429cc840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffe24dfba88 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffe24dfbd90 RCX: 00007feb429cc840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 000055a285a11660 RBP: 000000000000000d R08: 00000000000001c0 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 000055a285a05040 R14: 00007ffe24dfbd50 R15: 000055a285a12b50