INFO: task syz-executor.2:414 blocked for more than 143 seconds. Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:20984 pid:414 tgid:414 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a3/0xd70 kernel/locking/mutex.c:752 new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 kernfs_fop_write_iter+0x3a4/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2087 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa81/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f79d327caef RSP: 002b:00007ffffdd59800 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f79d327caef RDX: 0000000000000003 RSI: 00007ffffdd59850 RDI: 0000000000000005 RBP: 00007f79d32ca045 R08: 0000000000000000 R09: 00007ffffdd59657 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 00007ffffdd59850 R14: 00007f79d3ed4620 R15: 0000000000000003 INFO: task syz-executor.1:432 blocked for more than 143 seconds. Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:20984 pid:432 tgid:432 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a3/0xd70 kernel/locking/mutex.c:752 del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 kernfs_fop_write_iter+0x3a4/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2087 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa81/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f811e67caef RSP: 002b:00007ffdf6d8f9e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f811e67caef RDX: 0000000000000001 RSI: 00007ffdf6d8fa30 RDI: 0000000000000005 RBP: 00007f811e6ca021 R08: 0000000000000000 R09: 00007ffdf6d8f837 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 R13: 00007ffdf6d8fa30 R14: 00007f811f2d4620 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 3 locks held by kworker/u4:2/42: 1 lock held by dhcpcd/4738: #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1096 2 locks held by getty/4824: #0: ffff88802a68e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by kworker/0:3/8987: #0: ffff888014c7a538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c7a538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90003b37d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90003b37d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 8 locks held by syz-executor.0/338: #0: ffff88807d428420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2794 [inline] #0: ffff88807d428420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff8880ac11bc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888022d06e88 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb83e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff888091dbb0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #4: ffff888091dbb0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff888091dbb0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292 #5: ffff8880b37ef250 (&devlink->lock_key#6){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x40/0x260 drivers/net/netdevsim/netdev.c:451 #7: ffffffff8e136578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #7: ffffffff8e136578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:995 4 locks held by syz-executor.2/414: #0: ffff88807d428420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2794 [inline] #0: ffff88807d428420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff888096e95088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888022d06da0 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb83e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 1 lock held by syz-executor.3/430: #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:697 [inline] #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3497 4 locks held by syz-executor.1/432: #0: ffff88807d428420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2794 [inline] #0: ffff88807d428420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff8880a8c0c488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888022d06e88 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb83e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 2 locks held by syz-executor.2/3279: #0: ffffffff8f36c910 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:501 #1: ffffffff8e136440 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4064 1 lock held by syz-executor.1/3284: #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48f/0x2400 drivers/net/tun.c:3107 2 locks held by syz-executor.3/3287: #0: ffffffff8f36c910 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:501 #1: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:421 2 locks held by syz-executor.4/3290: #0: ffffffff8f36c910 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:501 #1: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10437 2 locks held by syz-executor.0/3296: #0: ffffffff8f36c910 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c7/0x7b0 net/core/net_namespace.c:501 #1: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: register_netdev+0x13/0x50 net/core/dev.c:10437 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1155 Comm: kworker/1:2 Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: events kfree_rcu_work RIP: 0010:__sanitizer_cov_trace_switch+0x6f/0x120 Code: 48 83 f8 07 0f 85 b9 00 00 00 41 b8 07 00 00 00 4d 85 d2 75 24 e9 a9 00 00 00 41 b8 01 00 00 00 4d 85 d2 75 14 e9 99 00 00 00 <41> b8 05 00 00 00 4d 85 d2 0f 84 8a 00 00 00 4c 8b 4c 24 20 65 4c RSP: 0018:ffffc900049ff4e0 EFLAGS: 00000246 RAX: 0000000000000003 RBX: 0000000000000000 RCX: ffff888022970000 RDX: ffffc900049ff615 RSI: ffffffff8dfa0180 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000003 R09: ffffffff81405417 R10: 0000000000000008 R11: ffff888022970000 R12: ffffffff8f9e1230 R13: dffffc0000000000 R14: ffffc900049ff630 R15: 1ffff9200093febc FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056269dac2131 CR3: 00000000a110c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x7c3/0x29e0 arch/x86/kernel/unwind_orc.c:515 arch_stack_walk+0x150/0x1b0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x117/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:589 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free_freelist_hook mm/slub.c:2150 [inline] slab_free_bulk mm/slub.c:4312 [inline] kmem_cache_free_bulk+0x1f8/0x350 mm/slub.c:4526 kfree_bulk include/linux/slab.h:507 [inline] kvfree_rcu_bulk+0x242/0x4b0 kernel/rcu/tree.c:3024 kfree_rcu_work+0x44b/0x500 kernel/rcu/tree.c:3103 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243