INFO: task syz.4.326:6751 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11516-g6b67e098c9c9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.326 state:D stack:23512 pid:6751 tgid:6750 ppid:5231 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 ppp_create_interface drivers/net/ppp/ppp_generic.c:3346 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] ppp_ioctl+0x789/0x1cd0 drivers/net/ppp/ppp_generic.c:733 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f999237dff9 RSP: 002b:00007f9993107038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9992535f80 RCX: 00007f999237dff9 RDX: 0000000020001400 RSI: 00000000c004743e RDI: 0000000000000018 RBP: 00007f99923f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9992535f80 R15: 00007ffc389ec778 INFO: task syz.4.326:6752 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11516-g6b67e098c9c9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.326 state:D stack:26936 pid:6752 tgid:6750 ppid:5231 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 ppp_ioctl+0x112/0x1cd0 drivers/net/ppp/ppp_generic.c:729 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f999237dff9 RSP: 002b:00007f99930e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9992536058 RCX: 00007f999237dff9 RDX: 0000000020000000 RSI: 000000004010744d RDI: 0000000000000018 RBP: 00007f99923f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9992536058 R15: 00007ffc389ec778 Showing all locks held in the system: 9 locks held by kworker/0:0/8: 3 locks held by kworker/0:1/9: #0: ffff88801ac81948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac81948 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900000e7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900000e7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x99/0xfd0 net/wireless/reg.c:2480 3 locks held by kworker/u8:1/12: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000117d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000117d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by khungtaskd/30: #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/u8:4/63: #0: ffff88814bae7148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814bae7148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900015e7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015e7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4196 3 locks held by kworker/0:2/937: 4 locks held by kworker/u8:7/2948: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90009e87d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90009e87d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcc5f50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:414 2 locks held by getty/4987: #0: ffff8880333a20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.4.326/6751: #0: ffffffff8f4baae8 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x112/0x1cd0 drivers/net/ppp/ppp_generic.c:729 #1: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: ppp_create_interface drivers/net/ppp/ppp_generic.c:3346 [inline] #1: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline] #1: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x789/0x1cd0 drivers/net/ppp/ppp_generic.c:733 1 lock held by syz.4.326/6752: #0: ffffffff8f4baae8 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x112/0x1cd0 drivers/net/ppp/ppp_generic.c:729 1 lock held by syz.1.341/6810: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: tc_new_tfilter+0x65e/0x1b70 net/sched/cls_api.c:2284 1 lock held by syz.0.351/6840: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: netdev_wait_allrefs_any net/core/dev.c:10682 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x89e/0x1000 net/core/dev.c:10793 1 lock held by syz.2.352/6844: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: packet_mc_add+0x28/0x950 net/packet/af_packet.c:3751 1 lock held by syz.3.357/6860: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6863: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6866: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6870: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6872: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6875: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6879: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6881: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6885: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6886: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6890: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6899: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6902: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6906: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6907: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6911: #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcd2a48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-11516-g6b67e098c9c9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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+0xff4/0x1040 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: 8 Comm: kworker/0:0 Not tainted 6.11.0-syzkaller-11516-g6b67e098c9c9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:__hlist_del include/linux/list.h:986 [inline] RIP: 0010:hlist_del include/linux/list.h:1002 [inline] RIP: 0010:__alloc_object lib/debugobjects.c:213 [inline] RIP: 0010:__free_object+0x30a/0xa80 lib/debugobjects.c:363 Code: 4d 8b 37 4d 85 f6 0f 84 5c 01 00 00 4c 89 64 24 18 4c 89 f3 48 c1 eb 03 42 80 3c 2b 00 74 08 4c 89 f7 e8 19 17 3c fd 4d 8b 26 <49> 8d 7e 08 49 89 ff 49 c1 ef 03 43 80 3c 2f 00 48 89 7c 24 20 74 RSP: 0018:ffffc900000078a0 EFLAGS: 00000046 RAX: 1ffff110170c74e8 RBX: 1ffff1100fa7a0e7 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff8c6100c0 RDI: ffffc900000079e0 RBP: ffffc90000007a70 R08: ffffc900000079ff R09: 0000000000000000 R10: ffffc90000007980 R11: fffff52000000f40 R12: ffff888031a53038 R13: dffffc0000000000 R14: ffff88807d3d0738 R15: ffff8880b863a740 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f78ca39af98 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:994 [inline] debug_check_no_obj_freed+0x293/0x580 lib/debugobjects.c:1019 slab_free_hook mm/slub.c:2274 [inline] slab_free mm/slub.c:4580 [inline] kmem_cache_free+0x11f/0x420 mm/slub.c:4682 dst_destroy+0x2ac/0x460 net/core/dst.c:124 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x75d/0xaa0 drivers/net/netdevsim/dev.c:850 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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