INFO: task syz-executor:9419 blocked for more than 143 seconds. Not tainted 6.13.0-rc1-syzkaller-00172-g11776cff0b56 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21280 pid:9419 tgid:9419 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 device_lock include/linux/device.h:1014 [inline] device_del+0xa6/0x9b0 drivers/base/core.c:3816 device_unregister+0x20/0xc0 drivers/base/core.c:3895 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline] del_device_store+0x363/0x480 drivers/net/netdevsim/bus.c:226 kernfs_fop_write_iter+0x3a0/0x500 fs/kernfs/file.c:334 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 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: 0033:0x7f3e9497e98f RSP: 002b:00007fff78a3e6d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f3e9497e98f RDX: 0000000000000001 RSI: 00007fff78a3e720 RDI: 0000000000000005 RBP: 00007f3e949f4ebd R08: 0000000000000000 R09: 00007fff78a3e527 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007fff78a3e720 R14: 00007f3e95674620 R15: 0000000000000003 Showing all locks held in the system: 6 locks held by kworker/R-netns/7: #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/0x1840 kernel/workqueue.c:3310 #1: ffffc900000c7c80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900000c7c80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fca2fd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:586 #3: ffff8880637200e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8880637200e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff8880637200e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x13b/0x440 net/devlink/core.c:506 #4: ffff8880692b0250 (&devlink->lock_key#21){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff8880692b0250 (&devlink->lock_key#21){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff8880692b0250 (&devlink->lock_key#21){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x14d/0x440 net/devlink/core.c:506 #5: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:816 4 locks held by ksoftirqd/0/16: 1 lock held by khungtaskd/30: #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:6/1104: #0: ffff88814d981148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814d981148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90003d6fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003d6fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4215 2 locks held by getty/5588: #0: ffff8880311fb0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 5 locks held by syz-executor/9419: #0: ffff88803618a420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff88803618a420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff888021f8c888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff88802799d5a8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55bae8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff8880637200e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8880637200e8 (&dev->mutex){....}-{4:4}, at: device_del+0xa6/0x9b0 drivers/base/core.c:3816 3 locks held by kworker/u8:14/9503: #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/0x1840 kernel/workqueue.c:3310 #1: ffffc9000bc07d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000bc07d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 3 locks held by kworker/u8:19/9520: 2 locks held by syz-executor/9945: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 #1: ffffffff8e7d2ed0 (cpu_hotplug_lock){++++}-{0:0}, at: flush_all_backlogs net/core/dev.c:6031 [inline] #1: ffffffff8e7d2ed0 (cpu_hotplug_lock){++++}-{0:0}, at: unregister_netdevice_many_notify+0x5ea/0x1da0 net/core/dev.c:11507 1 lock held by syz.1.1071/10034: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.4.1072/10033: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz.0.1075/10049: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 1 lock held by syz-executor/10053: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xbb0/0x20e0 net/core/rtnetlink.c:4008 1 lock held by syz-executor/10054: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xbb0/0x20e0 net/core/rtnetlink.c:4008 4 locks held by syz-executor/10061: #0: ffff88803618a420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff88803618a420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff88805ec87888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff88802799d5a8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55bae8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 1 lock held by syz-executor/10067: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 1 lock held by syz-executor/10070: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 4 locks held by syz-executor/10085: #0: ffff88803618a420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff88803618a420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff888024740888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff88802799d5a8 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55bae8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 1 lock held by syz-executor/10091: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 1 lock held by syz-executor/10097: #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fcaf448 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc1-syzkaller-00172-g11776cff0b56 #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:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 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: 16 Comm: ksoftirqd/0 Not tainted 6.13.0-rc1-syzkaller-00172-g11776cff0b56 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__refcount_add include/linux/refcount.h:189 [inline] RIP: 0010:__refcount_inc include/linux/refcount.h:241 [inline] RIP: 0010:refcount_inc include/linux/refcount.h:258 [inline] RIP: 0010:__skb_ext_copy include/linux/skbuff.h:4858 [inline] RIP: 0010:skb_ext_copy include/linux/skbuff.h:4866 [inline] RIP: 0010:ip_copy_metadata+0x7cf/0xe40 net/ipv4/ip_output.c:571 Code: 03 42 80 3c 28 00 74 08 48 89 df e8 bb c9 dd f7 4c 8b 33 4c 89 f7 be 04 00 00 00 e8 4b cc dd f7 bb 01 00 00 00 f0 41 0f c1 1e <31> ff 89 de e8 08 e6 72 f7 85 db 4c 8b 64 24 20 0f 84 0f 01 00 00 RSP: 0018:ffffc90000156118 EFLAGS: 00000202 RAX: 1ffff11012373501 RBX: 0000000000000001 RCX: ffffffff8a2c9045 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff888091b9b400 RBP: 1ffff11012373837 R08: ffff888091b9b403 R09: 1ffff11012373680 R10: dffffc0000000000 R11: ffffed1012373681 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff888091b9b400 R15: ffff888091b9ac80 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0fec90a2d8 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip_frag_next+0xfe/0xb30 net/ipv4/ip_output.c:704 ip_do_fragment+0x8d3/0x1b30 net/ipv4/ip_output.c:906 br_nf_ip_fragment net/bridge/br_netfilter_hooks.c:849 [inline] br_nf_dev_queue_xmit+0x17e1/0x2390 net/bridge/br_netfilter_hooks.c:918 NF_HOOK+0x700/0x7c0 include/linux/netfilter.h:314 br_nf_post_routing+0xa20/0xe80 net/bridge/br_netfilter_hooks.c:997 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66 br_nf_forward_finish+0xb49/0xfb0 net/bridge/br_netfilter_hooks.c:693 NF_HOOK+0x700/0x7c0 include/linux/netfilter.h:314 br_nf_forward_ip+0x61e/0x7b0 net/bridge/br_netfilter_hooks.c:747 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312 __br_forward+0x489/0x660 net/bridge/br_forward.c:115 br_handle_frame_finish+0x18ba/0x1fe0 net/bridge/br_input.c:215 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:1198 [inline] br_nf_pre_routing_finish+0x15c8/0x1fd0 net/bridge/br_netfilter_hooks.c:453 NF_HOOK+0x700/0x7c0 include/linux/netfilter.h:314 br_nf_pre_routing+0xead/0x1470 net/bridge/br_netfilter_hooks.c:562 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x14eb/0x4690 net/core/dev.c:5566 __netif_receive_skb_one_core net/core/dev.c:5670 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6883 napi_poll net/core/dev.c:6952 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7074 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 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