INFO: task kworker/u4:0:13748 blocked for more than 143 seconds. Not tainted 5.15.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:0 state:D stack:22096 pid:13748 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 tc_action_net_exit include/net/act_api.h:155 [inline] gate_exit_net+0x2c/0x100 net/sched/act_gate.c:624 ops_exit_list net/core/net_namespace.c:171 [inline] cleanup_net+0x7ec/0xc50 net/core/net_namespace.c:591 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91c180 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by systemd-journal/2962: #0: ffff8880b9d31558 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:474 [inline] #0: ffff8880b9d31558 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1317 [inline] #0: ffff8880b9d31558 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1620 [inline] #0: ffff8880b9d31558 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x188/0x1270 kernel/sched/core.c:6201 1 lock held by in:imklog/6222: #0: ffff88801da3ed70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:990 4 locks held by kworker/u4:0/13748: #0: ffff8881443ab138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc900033bfd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d94fbb0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf0/0xc50 net/core/net_namespace.c:553 #3: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: tc_action_net_exit include/net/act_api.h:155 [inline] #3: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: gate_exit_net+0x2c/0x100 net/sched/act_gate.c:624 3 locks held by kworker/0:2/21683: #0: ffff888011065d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc90006a3fd20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x7a/0x800 net/wireless/reg.c:2423 3 locks held by kworker/0:10/26480: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000a127d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 3 locks held by kworker/0:13/26483: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000a157d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 2 locks held by kworker/1:13/26580: #0: ffff888011066538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000b2f7d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 3 locks held by kworker/u4:2/30944: #0: ffff888141dcc938 ((wq_completion)cfg80211){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000675fd20 ((work_completion)(&(&rdev->dfs_update_channels_wk)->work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: cfg80211_dfs_channels_update_work+0xbc/0x660 net/wireless/mlme.c:842 3 locks held by kworker/0:15/31305: #0: ffff888026376d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000bc9fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xdb/0x1d10 net/ipv6/addrconf.c:4047 3 locks held by kworker/1:17/31547: #0: ffff888026376d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc9000c8cfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xdb/0x1d10 net/ipv6/addrconf.c:4047 1 lock held by syz-executor.5/1591: #0: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3c/0x130 drivers/net/tun.c:3397 1 lock held by syz-executor.1/1596: #0: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:684 [inline] #0: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3c/0x130 drivers/net/tun.c:3397 2 locks held by syz-executor.0/1603: #0: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d95b808 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 #1: ffffffff8c920968 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8c920968 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x277/0x750 kernel/rcu/tree_exp.h:837 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc54/0xca0 kernel/hung_task.c:295 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2962 Comm: systemd-journal Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unwind_get_return_address+0x51/0x80 arch/x86/kernel/unwind_orc.c:318 Code: 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 30 dd 93 00 48 8b 3b e8 d8 91 1c 00 85 c0 74 14 43 80 3c 37 00 <74> 08 48 89 df e8 15 dd 93 00 48 8b 03 eb 02 31 c0 5b 41 5e 41 5f RSP: 0018:ffffc90000dc0740 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc90000dc07a8 RCX: 0000000000000100 RDX: ffffc9000257fd18 RSI: 0000000000000000 RDI: ffffffff815101df RBP: ffffc90000dc07f0 R08: dffffc0000000000 R09: ffffc90000dc07b0 R10: fffff520001b80f8 R11: 0000000000000000 R12: ffff88807b1b5580 R13: ffffffff816fe150 R14: dffffc0000000000 R15: 1ffff920001b80f5 FS: 00007f57746b88c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f577140a000 CR3: 000000001f892000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 000000000000d0eb DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0xf8/0x140 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x11b/0x1e0 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0x10d/0x150 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1700 [inline] slab_free_freelist_hook+0x129/0x1a0 mm/slub.c:1725 slab_free mm/slub.c:3483 [inline] kmem_cache_free+0x85/0x180 mm/slub.c:3499 rcu_do_batch kernel/rcu/tree.c:2508 [inline] rcu_core+0x9b8/0x1610 kernel/rcu/tree.c:2743 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:193 Code: 84 00 00 00 00 00 0f 1f 40 00 be 0d 00 00 00 48 c7 c7 c0 8b 95 8c e8 2f 4d 4b 00 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0c 25 c0 ef 01 00 65 8b 15 34 7a 7f 7e f7 c2 RSP: 0018:ffffc9000257fd18 EFLAGS: 00000a02 RAX: f3f3f300f1f1f1f1 RBX: ffffffff8c7d4100 RCX: ffff88807b1b5580 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c7c99a0 RBP: ffffc9000257fdd0 R08: ffffffff8157bc30 R09: fffffbfff18fa839 R10: fffffbfff18fa839 R11: 0000000000000000 R12: ffffc9000257fd60 R13: ffffffff8c7c99a0 R14: dffffc0000000000 R15: 1ffff920004affa8 free_uid+0x6f/0x1e0 kernel/user.c:179 put_cred_rcu+0x1f1/0x400 kernel/cred.c:122 do_faccessat+0x798/0x940 fs/open.c:462 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f57739739c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffd5cac40b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffd5cac70e0 RCX: 00007f57739739c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055582f7699a3 RBP: 00007ffd5cac4200 R08: 000055582f75f3e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000055583026a8a0 R15: 00007ffd5cac46f0 ---------------- Code disassembly (best guess): 0: 83 c3 48 add $0x48,%ebx 3: 49 89 df mov %rbx,%r15 6: 49 c1 ef 03 shr $0x3,%r15 a: 43 80 3c 37 00 cmpb $0x0,(%r15,%r14,1) f: 74 08 je 0x19 11: 48 89 df mov %rbx,%rdi 14: e8 30 dd 93 00 callq 0x93dd49 19: 48 8b 3b mov (%rbx),%rdi 1c: e8 d8 91 1c 00 callq 0x1c91f9 21: 85 c0 test %eax,%eax 23: 74 14 je 0x39 25: 43 80 3c 37 00 cmpb $0x0,(%r15,%r14,1) * 2a: 74 08 je 0x34 <-- trapping instruction 2c: 48 89 df mov %rbx,%rdi 2f: e8 15 dd 93 00 callq 0x93dd49 34: 48 8b 03 mov (%rbx),%rax 37: eb 02 jmp 0x3b 39: 31 c0 xor %eax,%eax 3b: 5b pop %rbx 3c: 41 5e pop %r14 3e: 41 5f pop %r15