INFO: task syz.0.165:851 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.165 state:D stack:0 pid:851 tgid:851 ppid:288 flags:0x00004006 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_timeout+0xb2/0x3a0 kernel/time/timer.c:2595 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x359/0x630 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x415/0x530 kernel/rcu/tree.c:4657 netdev_run_todo+0x10e/0xcb0 net/core/dev.c:10868 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:3517 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e3/0x250 kernel/task_work.c:240 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x9bc/0x2630 kernel/exit.c:953 do_group_exit+0x22a/0x300 kernel/exit.c:1095 get_signal+0x139d/0x14f0 kernel/signal.c:2933 arch_do_signal_or_restart+0x96/0x720 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+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fe2e1dc14a5 RSP: 002b:00007fe2e2c8ff80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007fe2e1fc5fa0 RCX: 00007fe2e1dc14a5 RDX: 00007fe2e2c8ffc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fe2e1e11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fe2e1fc6038 R14: 00007fe2e1fc5fa0 R15: 00007fffbc014d88 INFO: task syz.1.424:1606 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.424 state:D stack:0 pid:1606 tgid:1605 ppid:290 flags:0x00004000 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_timeout+0xb2/0x3a0 kernel/time/timer.c:2595 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common+0x359/0x630 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 exit_aio+0x2df/0x3b0 fs/aio.c:927 __mmput+0x30/0x320 kernel/fork.c:1346 mmput+0x55/0x170 kernel/fork.c:1372 exit_mm kernel/exit.c:574 [inline] do_exit+0x918/0x2630 kernel/exit.c:940 do_group_exit+0x22a/0x300 kernel/exit.c:1095 get_signal+0x139d/0x14f0 kernel/signal.c:2933 arch_do_signal_or_restart+0x96/0x720 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+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f6bc738ebe9 RSP: 002b:00007f6bc81f3fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffffc RBX: 00007f6bc75c5fa0 RCX: 00007f6bc738ebe9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000080842011 RBP: 00007f6bc7411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f6bc75c6038 R14: 00007f6bc75c5fa0 R15: 00007ffe2ebb2768 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 3f7d833acb9715dc4d925f14855ea176aa3f9a02 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+0x64/0xa0 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: 33 Comm: rcuop/1 Not tainted syzkaller #0 3f7d833acb9715dc4d925f14855ea176aa3f9a02 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:user_mode arch/x86/include/asm/ptrace.h:214 [inline] RIP: 0010:unwind_next_frame+0x263/0x750 arch/x86/kernel/unwind_frame.c:290 Code: 80 3c 10 00 74 1a 4c 89 ef 48 89 4d c8 e8 25 eb 97 00 48 8b 4d c8 48 ba 00 00 00 00 00 fc ff df 49 3b 4d 00 0f 85 97 00 00 00 <4d> 8d 7e e0 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 1d 04 00 RSP: 0018:ffffc900002301c8 EFLAGS: 00000246 RAX: 1ffff110206cfbe4 RBX: ffffc90000230248 RCX: 0000000000230200 RDX: dffffc0000000000 RSI: ffffffff810998ca RDI: ffffc90000227f48 RBP: ffffc90000230238 R08: ffffc90000230310 R09: ffffc90000230308 R10: 0000000000000014 R11: ffffffff817441e0 R12: 0000000000000000 R13: ffff88810367df20 R14: ffffc90000228000 R15: ffffc90000227f48 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbce14f7d60 CR3: 000000010b370000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000d92 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x139/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9d/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:69 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565 unpoison_slab_object mm/kasan/common.c:320 [inline] __kasan_slab_alloc+0x73/0x90 mm/kasan/common.c:346 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4169 [inline] slab_alloc_node mm/slub.c:4218 [inline] kmem_cache_alloc_noprof+0x131/0x3a0 mm/slub.c:4227 skb_clone+0x229/0x460 net/core/skbuff.c:2082 deliver_clone net/bridge/br_forward.c:125 [inline] br_flood+0x661/0x730 net/bridge/br_forward.c:245 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+0xf4b/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 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5c6/0xd20 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 126720 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:36:9e:40:54:08:99, 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:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:36:9e:40:54:08:99, 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:36:9e:40:54:08:99, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:36:9e:40:54:08:99, vlan:0)