INFO: task syz-executor:24975 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:24024 pid:24975 tgid:24975 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760 nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 nfsd_umount+0x48/0xe0 fs/nfsd/nfsctl.c:1386 deactivate_locked_super+0xbe/0x1a0 fs/super.c:474 deactivate_super fs/super.c:507 [inline] deactivate_super+0xde/0x100 fs/super.c:503 cleanup_mnt+0x225/0x450 fs/namespace.c:1318 task_work_run+0x150/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xdd/0x100 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x419/0x4b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7cf71901f7 RSP: 002b:00007ffcb7220398 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f7cf7211d7d RCX: 00007f7cf71901f7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcb7220450 RBP: 00007ffcb7220450 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcb72214e0 R13: 00007f7cf7211d7d R14: 000000000013f706 R15: 00007ffcb7221520 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e1c34a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e1c34a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e1c34a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:4/59: #0: ffff88801bef6948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238 #1: ffffc9000210fd10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239 #2: ffffffff8fec45b0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x8b0 net/core/net_namespace.c:669 #3: ffffffff8feda948 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0x8b/0xaf0 net/core/dev.c:12719 2 locks held by getty/5599: #0: ffff88803445b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz.2.1219/12636: 2 locks held by syz-executor/24975: #0: ffff8880701c60e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880701c60e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880701c60e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: deactivate_super fs/super.c:506 [inline] #0: ffff8880701c60e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:503 #1: ffffffff8e5e4e28 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 2 locks held by syz.1.4059/27140: #0: ffffffff8ff7df90 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e5e4e28 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1629 2 locks held by syz.6.4357/28774: #0: ffffffff8ff7df90 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e5e4e28 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919 2 locks held by syz.0.4364/28817: #0: ffffffff8ff7df90 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e5e4e28 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919 3 locks held by syz.3.4549/29938: #0: ffff8880574230a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline] #0: ffff8880574230a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:345 [inline] #0: ffff8880574230a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] #0: ffff8880574230a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0x86/0x2e0 drivers/tty/tty_ldisc.c:780 #1: ffff8880a85df0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:295 [inline] #1: ffff8880a85df0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:347 [inline] #1: ffff8880a85df0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] #1: ffff8880a85df0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0xb0/0x2e0 drivers/tty/tty_ldisc.c:780 #2: ffffffff8e1ce900 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3815 2 locks held by syz.3.4549/29940: #0: ffffffff8fec45b0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 #1: ffffffff8e1cea38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343 2 locks held by syz.8.4550/29949: #0: ffffffff8fec45b0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576 #1: ffffffff8feda948 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline] #1: ffffffff8feda948 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7e9/0xab0 net/core/net_namespace.c:248 2 locks held by dhcpcd-run-hook/29980: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/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+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x730 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: 12636 Comm: syz.2.1219 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__module_address+0x27/0x210 kernel/module/main.c:3823 Code: 90 90 90 66 0f 1f 00 41 57 41 56 41 55 41 54 55 53 48 83 ec 08 48 3b 3d 17 f9 3b 0c 72 0c 48 39 3d 16 f9 3b 0c 48 89 fb 73 19 <45> 31 ed 48 83 c4 08 4c 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f e9 d0 RSP: 0018:ffffc90000a08578 EFLAGS: 00000217 RAX: 0000000000000001 RBX: 00007f9176b8eec9 RCX: 00000000517a802a RDX: 0000000000000000 RSI: ffffffff8bd00d40 RDI: 00007f9176b8eec9 RBP: 00007f9176b8eec9 R08: 37647e0e4f9ca5fd R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000000 R12: ffffffff81a5e750 R13: ffffc90000a086d8 R14: 0000000000000000 R15: ffff888025f30000 FS: 00007f9177a056c0(0000) GS:ffff888124f66000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d1ad3fc950 CR3: 0000000029e7c000 CR4: 00000000003526f0 Call Trace: __module_text_address kernel/module/main.c:3871 [inline] is_module_text_address+0x49/0x220 kernel/module/main.c:3846 kernel_text_address kernel/extable.c:119 [inline] kernel_text_address+0x81/0x100 kernel/extable.c:94 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xa6/0x100 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4191 [inline] slab_alloc_node mm/slub.c:4240 [inline] kmem_cache_alloc_node_noprof+0x1d5/0x3b0 mm/slub.c:4292 __alloc_skb+0x2b2/0x380 net/core/skbuff.c:659 skb_copy+0x1c9/0x3a0 net/core/skbuff.c:2124 mac80211_hwsim_tx_frame_no_nl.isra.0+0xb6e/0x13c0 drivers/net/wireless/virtual/mac80211_hwsim.c:1871 mac80211_hwsim_tx_frame+0x1f1/0x2a0 drivers/net/wireless/virtual/mac80211_hwsim.c:2222 __mac80211_hwsim_beacon_tx drivers/net/wireless/virtual/mac80211_hwsim.c:2239 [inline] mac80211_hwsim_beacon_tx+0x592/0xa40 drivers/net/wireless/virtual/mac80211_hwsim.c:2323 __iterate_interfaces+0x2e2/0x650 net/mac80211/util.c:761 ieee80211_iterate_active_interfaces_atomic+0x71/0x1b0 net/mac80211/util.c:797 mac80211_hwsim_beacon+0x105/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2353 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:510 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline] kernel_fpu_end+0x5e/0x70 arch/x86/kernel/fpu/core.c:479 sha256_blocks_avx2+0x4e/0x80 lib/crypto/x86/sha256.h:31 sha256_blocks lib/crypto/x86/sha256.h:37 [inline] __sha256_update+0x123/0x140 lib/crypto/sha256.c:207 crypto_sha256_update+0x23/0x30 crypto/sha256.c:142 crypto_shash_finup+0x360/0x6d0 crypto/shash.c:123 crypto_shash_update include/crypto/hash.h:994 [inline] ima_calc_file_hash_tfm+0x297/0x350 security/integrity/ima/ima_crypto.c:491 ima_calc_file_shash security/integrity/ima/ima_crypto.c:511 [inline] ima_calc_file_hash+0x1ba/0x490 security/integrity/ima/ima_crypto.c:568 ima_collect_measurement+0x899/0xa40 security/integrity/ima/ima_api.c:293 process_measurement+0x11fa/0x23e0 security/integrity/ima/ima_main.c:405 ima_file_mmap+0x1b1/0x1d0 security/integrity/ima/ima_main.c:495 security_mmap_file+0x88c/0x990 security/security.c:3051 vm_mmap_pgoff+0xec/0x470 mm/util.c:574 ksys_mmap_pgoff+0x1c8/0x5c0 mm/mmap.c:604 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9176b8eec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9177a05038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f9176de5fa0 RCX: 00007f9176b8eec9 RDX: 00004000000000df RSI: 0000010000000004 RDI: 0000000000000008 RBP: 00007f9176c11f91 R08: 0000000000000004 R09: 0000300000000000 R10: 0000000000040eb1 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9176de6038 R14: 00007f9176de5fa0 R15: 00007ffdb66a63c8