INFO: task syz.2.63:6411 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.63 state:D stack:28176 pid:6411 tgid:6390 ppid:5855 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244 inode_lock include/linux/fs.h:870 [inline] open_last_lookups fs/namei.c:3804 [inline] path_openat+0x8e6/0x3840 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f75d3e7eec9 RSP: 002b:00007f75d20c5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f75d40d6090 RCX: 00007f75d3e7eec9 RDX: 000000000000275a RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007f75d3f01f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f75d40d6128 R14: 00007f75d40d6090 R15: 00007ffe6102d6f8 Showing all locks held in the system: 1 lock held by khungtaskd/39: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:3/57: #0: ffff88801f2f9938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801f2f9938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000123fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000123fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff8880232b20d0 (&type->s_umount_key#60){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff88805988bcc8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 7 locks held by kworker/u8:9/1468: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc900053bfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900053bfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc6a20 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffff88802a0530d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff88802a0530d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88802a0530d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506 #4: ffff88802a055300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff88802a055300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88802a055300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506 #5: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xe5/0x670 drivers/net/netdevsim/netdev.c:1135 #6: ffff88805abb8e90 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2761 [inline] #6: ffff88805abb8e90 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x52f/0x1fe0 net/core/dev.c:12125 2 locks held by kworker/u8:12/3620: 2 locks held by getty/5599: #0: ffff88823bf708a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 9 locks held by syz-executor/5843: 1 lock held by syz-executor/5847: #0: ffff8880399200d0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880399200d0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880399200d0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 3 locks held by udevd/5893: 1 lock held by udevd/5906: 4 locks held by kworker/0:2H/6070: 4 locks held by syz.2.63/6391: 2 locks held by syz.2.63/6411: #0: ffff8880232b2488 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff88805988c098 (&type->i_mutex_dir_key#12){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline] #1: ffff88805988c098 (&type->i_mutex_dir_key#12){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3804 [inline] #1: ffff88805988c098 (&type->i_mutex_dir_key#12){+.+.}-{4:4}, at: path_openat+0x8e6/0x3840 fs/namei.c:4043 2 locks held by syz.5.256/7706: 2 locks held by syz-executor/7709: #0: ffffffff8ecc6a20 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566 #1: ffffffff8ecd3938 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160 3 locks held by rm/7724: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5893 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:memory_is_nonzero mm/kasan/generic.c:103 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x7d/0x2c0 mm/kasan/generic.c:189 Code: 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df 4f 8d 1c 17 49 ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df 4d 8d 34 19 <4d> 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 41 01 00 00 4c RSP: 0018:ffffc90004f7f3c8 EFLAGS: 00000a03 RAX: ffffffff81bb2701 RBX: dffffc0000000001 RCX: ffffffff81bb27ce RDX: 0000000000000001 RSI: 0000000000000018 RDI: ffffc90004f7f480 RBP: 0000000000000000 R08: ffffc90004f7f497 R09: 1ffff920009efe92 R10: dffffc0000000000 R11: fffff520009efe90 R12: 1ffff920009efe8c R13: dffffc0000000000 R14: fffff520009efe93 R15: 1ffff920009efe90 FS: 00007f69270c5880(0000) GS:ffff8881269bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f09d5df0000 CR3: 0000000023c0c000 CR4: 00000000003526f0 Call Trace: __asan_memset+0x22/0x50 mm/kasan/shadow.c:84 audit_log_format+0xae/0x130 kernel/audit.c:2007 audit_log_lsm_data+0xede/0x16d0 security/lsm_audit.c:268 dump_common_audit_data security/lsm_audit.c:421 [inline] common_lsm_audit+0x20d/0x2e0 security/lsm_audit.c:451 smack_log+0x394/0x3f0 security/smack/smack_access.c:391 smk_tskacc+0x2fc/0x370 security/smack/smack_access.c:255 smack_inode_permission+0x28f/0x320 security/smack/smack_lsm.c:1217 security_inode_permission+0xf8/0x310 security/security.c:2324 may_o_create fs/namei.c:3534 [inline] lookup_open fs/namei.c:3671 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x1426/0x3840 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f69271b3407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffd2a131220 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f69270c5880 RCX: 00007f69271b3407 RDX: 0000000000080241 RSI: 00007ffd2a131780 RDI: ffffffffffffff9c RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001b6 R11: 0000000000000202 R12: 000056402d134dfc R13: 000056402d134dfc R14: 0000000000000001 R15: 0000564054f93ba0