INFO: task syz-executor:527 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:527 tgid:527 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 __schedule_loop kernel/sched/core.c:7924 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7939 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589 netdev_run_todo+0x118/0xce0 net/core/dev.c:10874 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+0x1fe/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+0x9e3/0x2650 kernel/exit.c:953 do_group_exit+0x229/0x2f0 kernel/exit.c:1095 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: 0033:0x7f5a2ad9c6aa RSP: 002b:00007ffdc06bf9c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f5a2ad9c6aa RDX: 0000000000000060 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffdc06bf9e0 R08: 00007ffdc06bf9dc R09: 0000000000000000 R10: 00007ffdc06bf9e0 R11: 0000000000000246 R12: 00007ffdc06bf9dc R13: 00000000000927c0 R14: 00000000000322f2 R15: 00007ffdc06c0120 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 001c7e68fa735976e9f6b7ad125989e1d2b10b0e Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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: 36 Comm: kauditd Not tainted syzkaller #0 001c7e68fa735976e9f6b7ad125989e1d2b10b0e Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:vsnprintf+0x0/0x1ad0 lib/vsprintf.c:2734 Code: 89 33 31 c0 eb 0a e8 9f a3 ec fb b8 f0 ff ff ff 5b 41 5e 5d c3 cc cc cc cc cc b8 43 34 02 03 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 60 48 RSP: 0018:ffffc9000025f358 EFLAGS: 00000246 RAX: ffffc9000025f370 RBX: ffffffff85e92620 RCX: ffffc9000025f3c0 RDX: ffffffff85e92620 RSI: 000000007fffffff RDI: ffffc9000025f5c0 RBP: ffffc9000025f450 R08: ffffc9000025f3d7 R09: 0000000000000000 R10: ffffc9000025f3c0 R11: fffff5200004be7b R12: 1ffff9200004be74 R13: dffffc0000000000 R14: ffffc9000025f5c0 R15: ffffc9000025f3c0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffecf4ce8c CR3: 000000010c322000 CR4: 00000000003526b0 Call Trace: print_time kernel/printk/printk.c:1387 [inline] info_print_prefix+0x183/0x4a0 kernel/printk/printk.c:1416 record_print_text+0x177/0x450 kernel/printk/printk.c:1465 printk_get_next_message+0x2ab/0x9e0 kernel/printk/printk.c:3037 console_emit_next_record kernel/printk/printk.c:3105 [inline] console_flush_all+0x3ab/0xac0 kernel/printk/printk.c:3239 __console_flush_and_unlock kernel/printk/printk.c:3298 [inline] console_unlock+0xf8/0x2c0 kernel/printk/printk.c:3338 vprintk_emit+0x282/0x650 kernel/printk/printk.c:2462 vprintk_default+0x2a/0x40 kernel/printk/printk.c:2477 vprintk+0x93/0xa0 kernel/printk/printk_safe.c:75 _printk+0xde/0x140 kernel/printk/printk.c:2487 kauditd_printk_skb kernel/audit.c:546 [inline] kauditd_hold_skb+0x1cc/0x230 kernel/audit.c:581 kauditd_send_queue+0x2c4/0x310 kernel/audit.c:766 kauditd_thread+0x4e0/0x740 kernel/audit.c:890 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: 121254 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:b2:2b:1a:c1:55:52, 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 veth0_to_bridge with own address as source address (addr:b2:2b:1a:c1:55:52, 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:b2:2b:1a:c1:55:52, 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:b2:2b:1a:c1:55:52, 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:b2:2b:1a:c1:55:52, vlan:0)