INFO: task syz.2.1284:9904 blocked for more than 143 seconds. Not tainted 6.11.0-rc3-syzkaller-00508-gd785ed945de6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1284 state:D stack:24672 pid:9904 tgid:9904 ppid:9676 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 pipe_release+0x4e/0x330 fs/pipe.c:727 __fput+0x24a/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efd3b579e79 RSP: 002b:00007ffe5825caf8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007efd3b717a80 RCX: 00007efd3b579e79 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007efd3b717a80 R08: 0000000000000006 R09: 00007ffe5825cddf R10: 00000000003ffbd4 R11: 0000000000000246 R12: 0000000000047810 R13: 00007ffe5825cbf0 R14: 00007ffe5825cc10 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e9382e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e9382e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e9382e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 5 locks held by kworker/u8:8/2485: #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90009157d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90009157d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc76050 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fc82b08 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa90 net/core/dev.c:11883 #4: ffffffff8e93d6b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #4: ffffffff8e93d6b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958 3 locks held by kworker/u8:10/2929: #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90009a27d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90009a27d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc82b08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by getty/4987: #0: ffff88802b19c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f162f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5222: 1 lock held by syz.2.1284/9904: #0: ffff88807d4db868 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x4e/0x330 fs/pipe.c:727 1 lock held by syz.2.1284/9906: #0: ffff88807d4db868 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc3-syzkaller-00508-gd785ed945de6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 2485 Comm: kworker/u8:8 Not tainted 6.11.0-rc3-syzkaller-00508-gd785ed945de6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: netns cleanup_net RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:19 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:87 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:123 [inline] RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] RIP: 0010:_raw_spin_lock_irqsave+0x75/0x120 kernel/locking/spinlock.c:162 Code: c7 44 24 10 f0 f1 c0 8b 49 89 e5 49 c1 ed 03 48 b8 f1 f1 f1 f1 00 f3 f3 f3 4b 89 44 3d 00 4c 89 e3 48 c1 eb 03 42 80 3c 3b 00 <74> 08 4c 89 e7 e8 41 dd 39 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 RSP: 0018:ffffc90009157140 EFLAGS: 00000246 RAX: f3f3f300f1f1f1f1 RBX: 1ffff9200122ae2c RCX: 61c8864680b583eb RDX: 0000000000000001 RSI: ffffc900091572a0 RDI: ffffffff950eccc8 RBP: ffffc900091571d0 R08: ffffc900091572a7 R09: 0000000000000000 R10: ffffc90009157280 R11: fffff5200122ae55 R12: ffffc90009157160 R13: 1ffff9200122ae28 R14: ffffffff950eccc8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdc1595700 CR3: 000000005e6ec000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:979 [inline] debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1020 slab_free_hook mm/slub.c:2219 [inline] slab_free mm/slub.c:4473 [inline] kfree+0x10f/0x360 mm/slub.c:4594 free_slab_obj_exts mm/slub.c:2031 [inline] unaccount_slab mm/slub.c:2457 [inline] __free_slab+0xc8/0x240 mm/slub.c:2553 __slab_free+0x31b/0x3d0 mm/slub.c:4384 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080 kmalloc_reserve+0xa8/0x2a0 net/core/skbuff.c:586 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:677 alloc_skb include/linux/skbuff.h:1320 [inline] nlmsg_new include/net/netlink.h:1015 [inline] mpls_netconf_notify_devconf+0x42/0xf0 net/mpls/af_mpls.c:1189 mpls_dev_notify+0x563/0x7a0 net/mpls/af_mpls.c:1642 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2032 [inline] call_netdevice_notifiers net/core/dev.c:2046 [inline] unregister_netdevice_many_notify+0xd81/0x1c40 net/core/dev.c:11352 unregister_netdevice_many net/core/dev.c:11414 [inline] default_device_exit_batch+0xa0f/0xa90 net/core/dev.c:11897 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x89d/0xcc0 net/core/net_namespace.c:626 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 IPVS: wlc: UDP 224.0.0.2:0 - no destination available