INFO: task syz-executor:985 blocked for more than 122 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:985 tgid:985 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __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+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 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: 0033:0x7fc3c7d58fd7 RSP: 002b:00007ffff5dc3860 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555556cd0500 RCX: 00007fc3c7d58fd7 RDX: 0000000000000028 RSI: 00007fc3c8b54670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffff5dc38c4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fc3c8b54670 R15: 0000000000000000 INFO: task syz-executor:988 blocked for more than 125 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:988 tgid:988 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __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+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 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: 0033:0x7f5252558fd7 RSP: 002b:00007ffef3f71810 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555572426500 RCX: 00007f5252558fd7 RDX: 0000000000000028 RSI: 00007f5253354670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffef3f71874 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f5253354670 R15: 0000000000000000 INFO: task syz-executor:990 blocked for more than 125 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:990 tgid:990 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __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+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 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: 0033:0x7fb758158fd7 RSP: 002b:00007ffe8b88c280 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555561d8a500 RCX: 00007fb758158fd7 RDX: 0000000000000028 RSI: 00007fb758f54670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe8b88c2e4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fb758f54670 R15: 0000000000000000 INFO: task syz-executor:992 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:992 tgid:992 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6054 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7867 __schedule_loop kernel/sched/core.c:7944 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7959 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8016 __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+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 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: 0033:0x7f6934758fd7 RSP: 002b:00007ffc97b96890 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555565eda500 RCX: 00007f6934758fd7 RDX: 0000000000000028 RSI: 00007f6935554670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc97b968f4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f6935554670 R15: 0000000000000000 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 a506770653dd131ce1f6b755c8f096a645f29717 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 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: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+0xe45/0xf90 kernel/hung_task.c:423 kthread+0x2c7/0x360 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 351 Comm: kworker/u8:8 Not tainted syzkaller #0 a506770653dd131ce1f6b755c8f096a645f29717 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 Workqueue: netns cleanup_net RIP: 0010:ip6table_mangle_hook+0x4/0x720 net/ipv6/netfilter/ip6table_mangle.c:70 Code: ff 89 d8 5b 41 5e 5d e9 da cf 9b 00 cc 66 0f 1f 84 00 00 00 00 00 b8 21 4a 92 79 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec e0 00 RSP: 0018:ffffc900000074e0 EFLAGS: 00000257 RAX: 1ffff110214d4db4 RBX: ffffffff8509ff20 RCX: ffff8881332fb900 RDX: ffffc90000007580 RSI: ffff88813eea6dc0 RDI: ffff88810a6a6200 RBP: ffffc90000007530 R08: ffff8881332fb900 R09: 0000000000000004 R10: 0000000000000000 R11: ffffffff8509ff20 R12: 0000000000000001 R13: ffff88810a6a6d98 R14: dffffc0000000000 R15: ffff88810a6a6da0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055621cc0faf8 CR3: 000000010cb56000 CR4: 00000000003526b0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: nf_hook include/linux/netfilter.h:272 [inline] NF_HOOK include/linux/netfilter.h:315 [inline] ipv6_rcv+0x1d3/0x240 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5801 [inline] __netif_receive_skb net/core/dev.c:5914 [inline] netif_receive_skb_internal net/core/dev.c:6000 [inline] netif_receive_skb+0x146/0x7b0 net/core/dev.c:6059 br_netif_receive_skb net/bridge/br_input.c:30 [inline] NF_HOOK include/linux/netfilter.h:317 [inline] br_pass_frame_up+0x126/0x1b0 net/bridge/br_input.c:70 br_handle_frame_finish+0x1178/0x1620 net/bridge/br_input.c:-1 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+0x106/0x2b0 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+0x7f7/0x1060 kernel/workqueue.c:3354 worker_thread+0xc99/0x13f0 kernel/workqueue.c:3435 kthread+0x2c7/0x360 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