INFO: task syz-executor:3216 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:3216 tgid:3216 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __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 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline] netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x66d/0x6f0 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fbec6790a23 RSP: 002b:00007ffda077d258 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fbec74e4620 RCX: 00007fbec6790a23 RDX: 0000000000000028 RSI: 00007fbec74e4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffda077d274 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fbec74e4670 R15: 0000000000000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 a29bcd2d578c4b9493db917853c72486663e8fa1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+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 a29bcd2d578c4b9493db917853c72486663e8fa1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: netns cleanup_net RIP: 0010:stackdepot_memcmp lib/stackdepot.c:528 [inline] RIP: 0010:find_stack lib/stackdepot.c:561 [inline] RIP: 0010:stack_depot_save_flags+0x19b/0x800 lib/stackdepot.c:618 Code: 7d 4c 8b 2c 08 49 39 d5 0f 84 80 00 00 00 45 89 d7 eb 09 4d 8b 6d 00 49 39 d5 74 72 45 39 65 10 75 f1 45 39 55 14 75 eb 31 c0 <49> 8b 0c c6 49 3b 4c c5 20 75 de 48 ff c0 41 39 c7 75 ed 83 fe 02 RSP: 0018:ffffc9000022fb50 EFLAGS: 00000216 RAX: 000000000000000e RBX: 0000000000000000 RCX: ffffffff84ffc266 RDX: ffff8881f5814680 RSI: 0000000000000001 RDI: 000000009bf1f13c RBP: ffffc9000022fbb0 R08: 000000006b56fee4 R09: 0000000085893517 R10: 0000000000000014 R11: ffffffff81744340 R12: 0000000008861468 R13: ffff888148d9a3a0 R14: ffffc9000022fbc0 R15: 0000000000000014 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2b270e7d60 CR3: 00000000072a8000 CR4: 00000000003526b0 Call Trace: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x4f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x4a/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2418 [inline] slab_free mm/slub.c:4667 [inline] kmem_cache_free+0x1c1/0x510 mm/slub.c:4774 kfree_skbmem net/core/skbuff.c:-1 [inline] __kfree_skb+0x18f/0x210 net/core/skbuff.c:1203 sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240 kfree_skb_reason include/linux/skbuff.h:1271 [inline] kfree_skb include/linux/skbuff.h:1280 [inline] macsec_start_xmit+0x7c7/0x3070 drivers/net/macsec.c:3528 __netdev_start_xmit include/linux/netdevice.h:4975 [inline] netdev_start_xmit include/linux/netdevice.h:4984 [inline] xmit_one net/core/dev.c:3662 [inline] dev_hard_start_xmit+0x218/0x770 net/core/dev.c:3678 __dev_queue_xmit+0x19cc/0x3790 net/core/dev.c:4514 dev_queue_xmit include/linux/netdevice.h:3141 [inline] br_dev_queue_push_xmit+0x553/0x6d0 net/bridge/br_forward.c:53 NF_HOOK include/linux/netfilter.h:317 [inline] br_forward_finish net/bridge/br_forward.c:66 [inline] NF_HOOK include/linux/netfilter.h:317 [inline] __br_forward+0x25c/0x390 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver net/bridge/br_forward.c:190 [inline] br_flood+0x50e/0x730 net/bridge/br_forward.c:236 br_handle_frame_finish+0x12bb/0x1720 net/bridge/br_input.c:215 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+0xf48/0x3940 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:6206 __napi_poll+0xd0/0x610 net/core/dev.c:6857 napi_poll net/core/dev.c:6926 [inline] net_rx_action+0x584/0xce0 net/core/dev.c:7048 handle_softirqs+0x1ab/0x630 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xa6/0x100 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+0x608/0x1940 net/ipv6/addrconf.c:3956 addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1 notifier_call_chain+0x10e/0x2c0 kernel/notifier.c:93 raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461 call_netdevice_notifiers_info net/core/dev.c:2067 [inline] call_netdevice_notifiers_extack net/core/dev.c:2105 [inline] call_netdevice_notifiers net/core/dev.c:2119 [inline] unregister_netdevice_many_notify+0xe32/0x1bd0 net/core/dev.c:11489 unregister_netdevice_many net/core/dev.c:11551 [inline] default_device_exit_batch+0x810/0x8a0 net/core/dev.c:12034 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x731/0xc70 net/core/net_namespace.c:642 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+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 98663 callbacks suppressed 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 veth0_to_bridge with own address as source address (addr:16:4f:9c:a4:a9:03, 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 veth0_to_bridge with own address as source address (addr:16:4f:9c:a4:a9:03, 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 veth0_to_bridge with own address as source address (addr:16:4f:9c:a4:a9:03, 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 veth0_to_bridge with own address as source address (addr:16:4f:9c:a4:a9:03, 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 veth0_to_bridge with own address as source address (addr:16:4f:9c:a4:a9:03, vlan:0)