INFO: task syz.3.2808:9188 blocked for more than 122 seconds. Not tainted 6.12.30-syzkaller-g73009db42b37 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.2808 state:D stack:0 pid:9188 tgid:9188 ppid:7237 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x132b/0x1e00 kernel/sched/core.c:7789 __schedule_loop kernel/sched/core.c:7870 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7885 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7942 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4574 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10864 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3517 __fput+0x1fe/0xa00 fs/file_table.c:431 ____fput+0x20/0x30 fs/file_table.c:459 task_work_run+0x1e3/0x250 kernel/task_work.c:240 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9b4/0x2630 kernel/exit.c:944 do_group_exit+0x22a/0x300 kernel/exit.c:1094 get_signal+0x139d/0x14f0 kernel/signal.c:2934 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0e715c1265 RSP: 002b:00007f0e72364f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f0e717b5fa0 RCX: 00007f0e715c1265 RDX: 00007f0e72364fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f0e71610d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0e717b5fa0 R15: 00007ffef88f0998 INFO: task syz.2.3091:10030 blocked for more than 124 seconds. Not tainted 6.12.30-syzkaller-g73009db42b37 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.3091 state:D stack:0 pid:10030 tgid:10030 ppid:8865 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x132b/0x1e00 kernel/sched/core.c:7789 __schedule_loop kernel/sched/core.c:7870 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7885 schedule_timeout+0xb2/0x3a0 kernel/time/timer.c:2595 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x359/0x630 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4642 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10864 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xc5/0x150 drivers/net/tun.c:3517 __fput+0x1fe/0xa00 fs/file_table.c:431 ____fput+0x20/0x30 fs/file_table.c:459 task_work_run+0x1e3/0x250 kernel/task_work.c:240 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9b4/0x2630 kernel/exit.c:944 do_group_exit+0x22a/0x300 kernel/exit.c:1094 get_signal+0x139d/0x14f0 kernel/signal.c:2934 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f0a729c1265 RSP: 002b:00007f0a738b6f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f0a72bb5fa0 RCX: 00007f0a729c1265 RDX: 00007f0a738b6fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f0a72a10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0a72bb5fa0 R15: 00007ffc79898a58 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.30-syzkaller-g73009db42b37 #0 e78244f41b0e2dd383d6ada64249d7f830c3c2f3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xd8f/0xed0 kernel/hung_task.c:423 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 478 Comm: kworker/u8:4 Not tainted 6.12.30-syzkaller-g73009db42b37 #0 e78244f41b0e2dd383d6ada64249d7f830c3c2f3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker RIP: 0010:kmem_cache_alloc_node_noprof+0x1a2/0x3b0 mm/slub.c:4271 Code: 0f 1f 44 00 00 48 8b 45 c8 0f 1f 44 00 00 65 48 8b 0c 25 28 00 00 00 48 3b 4d d0 0f 85 b4 00 00 00 48 83 c4 20 5b 41 5c 41 5d <41> 5e 41 5f 5d e9 c4 81 b0 03 cc 4c 8d 45 c8 b9 01 00 00 00 4c 89 RSP: 0018:ffffc90000230570 EFLAGS: 00000282 RAX: ffff88812fd54700 RBX: ffffc900002305fc RCX: 566a83cf03e93900 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88812fd54a00 RBP: ffffc90000230580 R08: 000000003ca22c39 R09: 0000000000000000 R10: ffff88812fd54700 R11: ffffffff81740950 R12: 1ffff920000460bf R13: 0000000000000800 R14: 0000000000000300 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffe9d39fdc CR3: 00000001212ba000 CR4: 00000000003526b0 Call Trace: kmalloc_reserve+0xcf/0x500 net/core/skbuff.c:596 __alloc_skb+0x144/0x370 net/core/skbuff.c:687 alloc_skb include/linux/skbuff.h:1331 [inline] nlmsg_new include/net/netlink.h:1015 [inline] fdb_notify+0x78/0x150 net/bridge/br_fdb.c:195 br_fdb_update+0x4b7/0x680 net/bridge/br_fdb.c:941 br_handle_frame_finish+0x39c/0x1720 net/bridge/br_input.c:141 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xf4b/0x3940 net/core/dev.c:5651 __netif_receive_skb_one_core net/core/dev.c:5755 [inline] __netif_receive_skb net/core/dev.c:5870 [inline] process_backlog+0x3e5/0xae0 net/core/dev.c:6202 __napi_poll+0xd0/0x610 net/core/dev.c:6853 napi_poll net/core/dev.c:6922 [inline] net_rx_action+0x584/0xce0 net/core/dev.c:7044 handle_softirqs+0x1ae/0x630 kernel/softirq.c:603 __do_softirq+0xf/0x16 kernel/softirq.c:641 do_softirq+0xa6/0x100 kernel/softirq.c:485 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:412 __raw_read_unlock_bh include/linux/rwlock_api_smp.h:257 [inline] _raw_read_unlock_bh+0x2d/0x40 kernel/locking/spinlock.c:284 wg_socket_send_skb_to_peer+0x176/0x1e0 drivers/net/wireguard/socket.c:184 wg_socket_send_buffer_to_peer+0x11c/0x170 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x1d8/0x240 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x7d5/0x1020 kernel/workqueue.c:3319 worker_thread+0xc58/0x1250 kernel/workqueue.c:3400 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 143648 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:66:be:99:37:4b:cd, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)