INFO: task kworker/u8:15:445 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:15 state:D stack:0 pid:445 tgid:445 ppid:2 flags:0x00004000 Workqueue: events_unbound linkwatch_event Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79 linkwatch_event+0x12/0x60 net/core/link_watch.c:285 process_one_work kernel/workqueue.c:3273 [inline] process_scheduled_works+0x7f4/0x1060 kernel/workqueue.c:3354 worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435 kthread+0x2c4/0x360 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz-executor:776 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:776 tgid:776 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79 fib_net_exit_batch+0x24/0xa0 net/ipv4/fib_frontend.c:1652 ops_exit_list net/core/net_namespace.c:178 [inline] setup_net+0x70c/0x9b0 net/core/net_namespace.c:388 copy_net_ns+0x4fc/0xa20 net/core/net_namespace.c:510 create_new_namespaces+0x390/0x6f0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228 ksys_unshare+0x4f9/0x920 kernel/fork.c:3385 __do_sys_unshare kernel/fork.c:3471 [inline] __se_sys_unshare kernel/fork.c:3469 [inline] __x64_sys_unshare+0x3c/0x50 kernel/fork.c:3469 x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f28c619f427 RSP: 002b:00007ffdb36c3628 EFLAGS: 00000202 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f28c6425f40 RCX: 00007f28c619f427 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007f28c64267b8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 00007ffdb36c3868 R15: 0000000000000000 INFO: task syz-executor:786 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:786 tgid:786 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2554 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1895 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] __sys_sendto+0x663/0x6e0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2200 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7ff8a39592d7 RSP: 002b:00007ffc03d72520 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055555fed3500 RCX: 00007ff8a39592d7 RDX: 000000000000004c RSI: 00007ff8a4754670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc03d72584 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007ff8a4754670 R15: 0000000000000000 INFO: task syz-executor:788 blocked for more than 126 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:788 tgid:788 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2554 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1895 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] __sys_sendto+0x663/0x6e0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2200 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f7ce19592d7 RSP: 002b:00007ffc4a7062c0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555572ceb500 RCX: 00007f7ce19592d7 RDX: 000000000000002c RSI: 00007f7ce2754670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc4a706324 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f7ce2754670 R15: 0000000000000000 INFO: task syz-executor:790 blocked for more than 127 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:790 tgid:790 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2554 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1895 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] __sys_sendto+0x663/0x6e0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2200 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f41091592d7 RSP: 002b:00007ffc7a5c8280 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555560525500 RCX: 00007f41091592d7 RDX: 000000000000004c RSI: 00007f4109f54670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc7a5c82e4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f4109f54670 R15: 0000000000000000 INFO: task syz-executor:792 blocked for more than 128 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:792 tgid:792 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8032 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24d/0x4e0 net/netlink/af_netlink.c:2554 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x8bc/0xa70 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1895 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] __sys_sendto+0x663/0x6e0 net/socket.c:2197 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2200 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f519a7592d7 RSP: 002b:00007ffd66f92060 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00005555730eb500 RCX: 00007f519a7592d7 RDX: 000000000000004c RSI: 00007f519b554670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffd66f920c4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f519b554670 R15: 0000000000000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 60889c1c5e6bdc1f3cb1b6a230ba908545dccc71 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:114 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:63 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 cpumask_backtrace+0x1f/0x30 lib/nmi_backtrace.c:127 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xe45/0xf90 kernel/hung_task.c:423 kthread+0x2c4/0x360 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 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: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 60889c1c5e6bdc1f3cb1b6a230ba908545dccc71 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: netns cleanup_net RIP: 0010:__sanitizer_cov_trace_pc+0x5/0x70 kernel/kcov.c:210 Code: e8 40 c8 54 00 5b 5d e9 19 59 20 04 cc cc cc cc cc cc cc cc cc b8 d2 74 eb ea 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <48> 89 e5 48 8b 45 08 65 48 8b 0d 0c 75 7d 7e 65 8b 15 0d 75 7d 7e RSP: 0018:ffffc90000230698 EFLAGS: 00000246 RAX: ffffffff851690f7 RBX: ffff888106fc2828 RCX: 0000000000000100 RDX: ffff888103651300 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000230750 R08: ffff888103651300 R09: 0000000000000003 R10: 0000000000000002 R11: 0000000000000100 R12: 00000000000048e0 R13: 0000000000000000 R14: 1ffff11020df8505 R15: ffff888106fc2818 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f174a34af8 CR3: 000000010c778000 CR4: 00000000003526b0 Call Trace: br_handle_frame_finish+0x1157/0x1620 net/bridge/br_input.c:215 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline] br_handle_frame+0x5a5/0xba0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xfc1/0x3a70 net/core/dev.c:5695 __netif_receive_skb_one_core net/core/dev.c:5799 [inline] __netif_receive_skb net/core/dev.c:5914 [inline] process_backlog+0x40b/0xaf0 net/core/dev.c:6250 __napi_poll+0xcd/0x600 net/core/dev.c:6901 napi_poll net/core/dev.c:6970 [inline] net_rx_action+0x5dc/0xd70 net/core/dev.c:7092 handle_softirqs+0x1aa/0x620 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xb8/0x110 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] addrconf_ifdown+0x60d/0x1970 net/ipv6/addrconf.c:3950 addrconf_notify+0x17a/0xeb0 net/ipv6/addrconf.c:-1 notifier_call_chain+0x103/0x2b0 kernel/notifier.c:93 raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461 call_netdevice_notifiers_info net/core/dev.c:2074 [inline] call_netdevice_notifiers_extack net/core/dev.c:2112 [inline] call_netdevice_notifiers net/core/dev.c:2126 [inline] unregister_netdevice_many_notify+0xde1/0x1be0 net/core/dev.c:11533 unregister_netdevice_many net/core/dev.c:11595 [inline] default_device_exit_batch+0x845/0x8d0 net/core/dev.c:12166 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x744/0xc90 net/core/net_namespace.c:642 process_one_work kernel/workqueue.c:3273 [inline] process_scheduled_works+0x7f4/0x1060 kernel/workqueue.c:3354 worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435 kthread+0x2c4/0x360 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 121459 callbacks suppressed 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: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: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 veth0_to_bridge with own address as source address (addr:96:e3:e0:a2:8a:b6, 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 veth0_to_bridge with own address as source address (addr:96:e3:e0:a2:8a:b6, vlan:0)