INFO: task syz.4.1929:9992 blocked for more than 144 seconds. Not tainted 6.16.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.1929 state:D stack:28888 pid:9992 tgid:9991 ppid:5823 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 ___down_common+0x2d8/0x460 kernel/locking/semaphore.c:268 __down_common kernel/locking/semaphore.c:293 [inline] __down+0x20/0x30 kernel/locking/semaphore.c:303 down+0x74/0xa0 kernel/locking/semaphore.c:100 console_lock+0x5b/0xa0 kernel/printk/printk.c:2849 do_fb_ioctl+0x491/0x7e0 drivers/video/fbdev/core/fb_chrdev.c:123 fb_ioctl+0xe5/0x150 drivers/video/fbdev/core/fb_chrdev.c:169 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1df9b8e9a9 RSP: 002b:00007f1dfaa2e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1df9db5fa0 RCX: 00007f1df9b8e9a9 RDX: 0000200000001940 RSI: 0000000000004606 RDI: 0000000000000003 RBP: 00007f1df9c10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1df9db5fa0 R15: 00007ffc47ee1528 Showing all locks held in the system: 2 locks held by kthreadd/2: 3 locks held by kworker/0:1/10: #0: ffff88801eeee148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900000f7d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888145391198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888145391198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898 4 locks held by kworker/u8:0/12: 4 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: 3 locks held by kworker/1:0/24: 1 lock held by kdevtmpfs/26: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4e00 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:2/36: 3 locks held by kworker/1:1/48: 3 locks held by kworker/u8:3/49: 4 locks held by kworker/u8:4/64: #0: ffff88807adf8948 ((wq_completion)wg-kex-wg2){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000210fd10 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88806a34d308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0xec/0x650 drivers/net/wireguard/noise.c:529 #3: ffff888029d5a0f0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_create_initiation+0x100/0x650 drivers/net/wireguard/noise.c:530 3 locks held by kworker/u8:5/796: 3 locks held by kworker/u8:6/1160: 2 locks held by kworker/0:2/1212: 3 locks held by kworker/1:2/3087: 1 lock held by kworker/R-ipv6_/3179: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 1 lock held by kworker/R-bat_e/3409: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 2 locks held by klogd/5189: 1 lock held by udevd/5200: 1 lock held by dhcpcd/5494: 3 locks held by crond/5569: 2 locks held by getty/5593: #0: ffff888032de70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5824: 1 lock held by syz-executor/5831: 2 locks held by syz-executor/5832: 1 lock held by kworker/R-wg-cr/5860: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 1 lock held by kworker/R-wg-cr/5865: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 1 lock held by kworker/R-wg-cr/5866: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 1 lock held by kworker/R-wg-cr/5867: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 1 lock held by kworker/R-wg-cr/5869: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 1 lock held by kworker/R-wg-cr/5870: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 3 locks held by kworker/1:3/5872: 1 lock held by kworker/R-wg-cr/5874: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_detach_from_pool kernel/workqueue.c:2736 [inline] #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: rescuer_thread+0x839/0xea0 kernel/workqueue.c:3531 1 lock held by kworker/R-wg-cr/5875: 4 locks held by kworker/1:4/5882: 4 locks held by kworker/1:5/5889: #0: ffff888059ba5d48 ((wq_completion)wg-kex-wg1#4){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000212fd10 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888036255308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff888029578338 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 3 locks held by kworker/1:6/5890: 2 locks held by kworker/0:3/5909: 1 lock held by kworker/1:7/5910: #0: ffffffff8e47bce8 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x27/0x420 kernel/workqueue.c:2678 4 locks held by kworker/1:8/5911: #0: ffff88805906a148 ((wq_completion)wg-kex-wg2#8){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000441fd10 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88807c2fd308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff888057c2c890 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 3 locks held by kworker/u8:7/5938: 3 locks held by kworker/0:4/5942: 2 locks held by kworker/0:5/5943: 4 locks held by kworker/0:7/5963: #0: ffff888059ba7948 ((wq_completion)wg-kex-wg2#4){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000464fd10 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888027ee1308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff888057c2a0f0 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 4 locks held by kworker/1:9/5978: #0: ffff888028c6e148 ((wq_completion)wg-kex-wg0#8){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000456fd10 ((work_completion)(&({ do { const void *__vpp_verify = (typeof((worker) + 0))((void *)0); (void)__vpp_verify; } while (0); ({ unsigned long __ptr; __asm__ ("" : "=r"(__ptr) : "0"((__typeof__(*((worker))) *)(( unsigned long)((worker))))); (typeof((__typeof__(*((worker))) *)(( unsigned long)((worker))))) (__ptr + (((__per_cpu_offset[(cpu)])))); }); })->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff8880262ad308 (&wg->static_identity.lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x1c2/0x880 drivers/net/wireguard/noise.c:598 #3: ffff888029578d20 (&handshake->lock){++++}-{4:4}, at: wg_noise_handshake_consume_initiation+0x5ac/0x880 drivers/net/wireguard/noise.c:632 3 locks held by kworker/u8:8/9553: 3 locks held by kworker/u8:9/9555: 3 locks held by kworker/u8:10/9557: 7 locks held by kworker/u8:11/9559: 4 locks held by kworker/u8:12/9562: 5 locks held by kworker/u8:13/9565: 4 locks held by kworker/u8:14/9567: 4 locks held by kworker/u8:15/9568: 4 locks held by syz.0.1881/9895: 4 locks held by kworker/u8:16/10019: 4 locks held by kworker/u8:17/10020: 2 locks held by syz-executor/10021: 4 locks held by kworker/u8:18/10022: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9559 Comm: kworker/u8:11 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker RIP: 0010:check_preemption_disabled+0x25/0xe0 lib/smp_processor_id.c:56 Code: 90 90 90 90 90 41 54 55 53 48 83 ec 08 65 8b 1d 05 6c 49 08 65 8b 05 fa 6b 49 08 a9 ff ff ff 7f 74 0f 48 83 c4 08 89 d8 5b 5d <41> 5c e9 14 df 02 00 9c 58 f6 c4 02 74 ea 48 89 fd 65 48 8b 05 ba RSP: 0018:ffffc90000006860 EFLAGS: 00000296 RAX: 0000000000000000 RBX: ffffc900000076a8 RCX: ffffc90000008001 RDX: ffffc900000076b0 RSI: ffffffff8c157360 RDI: ffffffff8c1573a0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000096339 R12: ffffc90000006948 R13: ffffc900000068f8 R14: ffffc900000076a8 R15: ffffc9000000692c FS: 0000000000000000(0000) GS:ffff888124720000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f046ab802d8 CR3: 0000000036b84000 CR4: 00000000003526f0 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:745 rcu_read_unlock include/linux/rcupdate.h:869 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xa92/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 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 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745 __skb_ext_put+0x102/0x2c0 net/core/skbuff.c:7154 __skb_ext_del+0xf3/0x340 net/core/skbuff.c:7121 skb_ext_del include/linux/skbuff.h:4892 [inline] nf_bridge_info_free net/bridge/br_netfilter_hooks.c:156 [inline] br_nf_dev_queue_xmit+0x7b7/0x2cb0 net/bridge/br_netfilter_hooks.c:922 NF_HOOK include/linux/netfilter.h:317 [inline] NF_HOOK include/linux/netfilter.h:311 [inline] br_nf_post_routing+0x8e7/0x1190 net/bridge/br_netfilter_hooks.c:969 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623 nf_hook+0x45e/0x780 include/linux/netfilter.h:272 NF_HOOK include/linux/netfilter.h:315 [inline] br_forward_finish+0xcd/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh+0x304/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_forward_finish+0x66a/0xba0 net/bridge/br_netfilter_hooks.c:665 NF_HOOK include/linux/netfilter.h:317 [inline] NF_HOOK include/linux/netfilter.h:311 [inline] br_nf_forward_ip.part.0+0x609/0x810 net/bridge/br_netfilter_hooks.c:719 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:679 [inline] br_nf_forward+0xf0f/0x1be0 net/bridge/br_netfilter_hooks.c:776 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623 nf_hook+0x45e/0x780 include/linux/netfilter.h:272 NF_HOOK include/linux/netfilter.h:315 [inline] __br_forward+0x1be/0x5b0 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] br_flood+0x39c/0x650 net/bridge/br_forward.c:249 br_handle_frame_finish+0xf2d/0x1ca0 net/bridge/br_input.c:221 br_nf_hook_thresh+0x304/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:317 [inline] br_nf_pre_routing_ipv6+0x3cd/0x8c0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0xad8/0x14b0 net/bridge/br_input.c:434 __netif_receive_skb_core.constprop.0+0xa26/0x4a00 net/core/dev.c:5863 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5975 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6090 process_backlog+0x442/0x15e0 net/core/dev.c:6442 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0xa9f/0xfe0 net/core/dev.c:7605 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 do_softirq kernel/softirq.c:480 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:467 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407 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:476 blake2s_compress+0x7f/0xe0 arch/x86/lib/crypto/blake2s-glue.c:46 blake2s_final+0xc9/0x150 lib/crypto/blake2s.c:54 hmac.constprop.0+0x252/0x420 drivers/net/wireguard/noise.c:325 kdf.constprop.0+0x14b/0x280 drivers/net/wireguard/noise.c:367 message_ephemeral+0x5f/0x70 drivers/net/wireguard/noise.c:493 wg_noise_handshake_create_initiation+0x2c6/0x650 drivers/net/wireguard/noise.c:545 wg_packet_send_handshake_initiation+0x19a/0x360 drivers/net/wireguard/send.c:34 wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245