INFO: task syz-executor:295 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:295 tgid:295 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6027 [inline] __schedule+0x14ce/0x2100 kernel/sched/core.c:7894 __schedule_loop kernel/sched/core.c:7975 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7990 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x369/0x650 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x415/0x540 kernel/rcu/tree.c:4657 netdev_run_todo+0x118/0xce0 net/core/dev.c:10912 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:3520 __fput+0x1fb/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e5/0x260 kernel/task_work.c:246 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9ad/0x2720 kernel/exit.c:954 do_group_exit+0x229/0x2f0 kernel/exit.c:1096 get_signal+0x1398/0x14e0 kernel/signal.c:2933 arch_do_signal_or_restart+0xbc/0x760 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+0x57/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fda0539e62a RSP: 002b:00007ffccc6d5168 EFLAGS: 00000202 ORIG_RAX: 0000000000000037 RAX: 0000000000000000 RBX: 00007ffccc6d51f0 RCX: 00007fda0539e62a RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffccc6d518c R09: 0000000000000000 R10: 00007ffccc6d51f0 R11: 0000000000000202 R12: 00007fda055eb680 R13: 00007ffccc6d518c R14: 0000000000000000 R15: 00007fda055ed180 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 471281939cd7bfdfff4c6b6074d5d68627c837ba Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c9/0x370 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: 20 Comm: rcuop/0 Not tainted syzkaller #0 471281939cd7bfdfff4c6b6074d5d68627c837ba Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:task_stack_page include/linux/sched/task_stack.h:23 [inline] RIP: 0010:last_frame arch/x86/kernel/unwind_frame.c:82 [inline] RIP: 0010:is_last_frame arch/x86/kernel/unwind_frame.c:87 [inline] RIP: 0010:is_last_task_frame arch/x86/kernel/unwind_frame.c:156 [inline] RIP: 0010:unwind_next_frame+0x10d/0x750 arch/x86/kernel/unwind_frame.c:276 Code: f7 e8 e7 ae 9b 00 48 ba 00 00 00 00 00 fc ff df 4c 89 75 98 49 8b 06 48 89 45 a8 4c 8d 68 20 4c 89 e8 48 c1 e8 03 80 3c 10 00 <74> 12 4c 89 ef e8 b9 ae 9b 00 48 ba 00 00 00 00 00 fc ff df 49 8b RSP: 0018:ffffc90000230028 EFLAGS: 00000246 RAX: 1ffff110206cc004 RBX: ffffc900002300a8 RCX: 0000000000230000 RDX: dffffc0000000000 RSI: ffffffff84885a33 RDI: ffffc900002300a8 RBP: ffffc90000230098 R08: ffffc90000230170 R09: ffffc90000230168 R10: 000000000000000c R11: ffffffff8175ee80 R12: 0000000000000000 R13: ffff888103660020 R14: ffffc900002300d0 R15: ffffc90000230be8 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcbb6c60620 CR3: 000000017f4e8000 CR4: 00000000003526b0 Call Trace: arch_stack_walk+0x138/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:49 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:70 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565 poison_kmalloc_redzone mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396 kasan_kmalloc include/linux/kasan.h:261 [inline] __kmalloc_cache_noprof+0x23c/0x470 mm/slub.c:4426 kmalloc_noprof include/linux/slab.h:881 [inline] kzalloc_noprof include/linux/slab.h:1017 [inline] ref_tracker_alloc+0x184/0x590 lib/ref_tracker.c:203 __netdev_tracker_alloc include/linux/netdevice.h:4142 [inline] netdev_hold include/linux/netdevice.h:4171 [inline] dst_init+0xcf/0x440 net/core/dst.c:52 dst_alloc+0x163/0x250 net/core/dst.c:94 rt_dst_alloc net/ipv4/route.c:1647 [inline] ip_route_input_slow net/ipv4/route.c:2385 [inline] ip_route_input_rcu+0x1a0e/0x2700 net/ipv4/route.c:2499 ip_route_input_noref+0xd4/0x150 net/ipv4/route.c:2510 arp_process+0x908/0x1790 net/ipv4/arp.c:841 NF_HOOK+0x181/0x1e0 include/linux/netfilter.h:317 arp_rcv+0x2f8/0x490 net/ipv4/arp.c:992 __netif_receive_skb_one_core net/core/dev.c:5801 [inline] __netif_receive_skb net/core/dev.c:5914 [inline] process_backlog+0x553/0xad0 net/core/dev.c:6250 __napi_poll+0xd0/0x610 net/core/dev.c:6901 napi_poll net/core/dev.c:6970 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7092 handle_softirqs+0x1aa/0x630 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 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957 kthread+0x2c9/0x370 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: 110873 callbacks suppressed 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) 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:1b, 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) 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) net_ratelimit: 137476 callbacks suppressed 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:e6:5e:f0:b7:f5:b5, 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:e6:5e:f0:b7:f5:b5, 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 veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)