INFO: task syz.2.188:932 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.188 state:D stack:0 pid:932 tgid:932 ppid:295 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6063 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7883 __schedule_loop kernel/sched/core.c:7960 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7975 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+0x368/0x650 kernel/sched/completion.c:127 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148 rcu_barrier+0x45a/0x580 kernel/rcu/tree.c:4657 netdev_run_todo+0x118/0xce0 net/core/dev.c:10912 rtnl_unlock+0x12/0x20 net/core/rtnetlink.c:152 ppp_release+0xf5/0x200 drivers/net/ppp/ppp_generic.c:423 __fput+0x208/0xa30 fs/file_table.c:447 ____fput+0x20/0x30 fs/file_table.c:475 task_work_run+0x1e5/0x260 kernel/task_work.c:246 resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x63/0xb0 kernel/entry/common.c:218 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f553b59e159 RSP: 002b:00007ffff4e13bf8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f553b827da0 RCX: 00007f553b59e159 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f553b827da0 R08: 00007f553b826038 R09: 0000000000000000 R10: 00000000003ff78c R11: 0000000000000246 R12: 000000000000d60b R13: 00007f553b82609c R14: 000000000000d432 R15: 00007f553b826090 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 01d0fef691542fecbcfb5551c0a705324fcaa78c Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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+0x2c4/0x360 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 33 Comm: rcuop/1 Not tainted syzkaller #0 01d0fef691542fecbcfb5551c0a705324fcaa78c Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:skb_pull_inline include/linux/skbuff.h:2814 [inline] RIP: 0010:eth_skb_pull_mac include/linux/etherdevice.h:643 [inline] RIP: 0010:eth_type_trans+0x15f/0x6f0 net/ethernet/eth.c:164 Code: 89 74 24 08 4d 8d 6e 70 4d 89 ee 49 c1 ee 03 43 0f b6 04 3e 84 c0 0f 85 32 03 00 00 4c 89 6c 24 18 45 8b 6d 00 bf 0e 00 00 00 <44> 89 ee e8 d9 22 eb fc 41 83 fd 0d 4c 89 64 24 28 0f 86 07 02 00 RSP: 0018:ffffc90000006fc0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000002 RCX: ffff88810367b900 RDX: 0000000000000100 RSI: ffff888107f02000 RDI: 000000000000000e RBP: ffffc900000070b8 R08: 1ffffffff0e81b12 R09: 0000000000000002 R10: 0000000000000000 R11: ffffffff8375a5c0 R12: ffff888107f02000 R13: 0000000000000046 R14: 1ffff110227cf376 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056115615faf8 CR3: 00000000074aa000 CR4: 00000000003526b0 Call Trace: __dev_forward_skb2+0x302/0x770 net/core/dev.c:2268 __dev_forward_skb+0x26/0x40 net/core/dev.c:2277 veth_forward_skb drivers/net/veth.c:322 [inline] veth_xmit+0x31c/0xb30 drivers/net/veth.c:378 __netdev_start_xmit include/linux/netdevice.h:5008 [inline] netdev_start_xmit include/linux/netdevice.h:5017 [inline] xmit_one net/core/dev.c:3693 [inline] dev_hard_start_xmit+0x230/0x730 net/core/dev.c:3709 __dev_queue_xmit+0x1969/0x3780 net/core/dev.c:4549 dev_queue_xmit include/linux/netdevice.h:3141 [inline] br_dev_queue_push_xmit+0x571/0x710 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+0x24f/0x390 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver net/bridge/br_forward.c:191 [inline] br_flood+0x500/0x720 net/bridge/br_forward.c:237 br_handle_frame_finish+0x1157/0x1620 net/bridge/br_input.c:215 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+0xfc4/0x3a70 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 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x590/0xcb0 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x533/0xb60 kernel/rcu/tree_nocb.h:957 kthread+0x2c4/0x360 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: 103072 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 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: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 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:ea:a7:c2:d9:61:4d, 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:ea:a7:c2:d9:61:4d, 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: 138724 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:ea:a7:c2:d9:61:4d, 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:ea:a7:c2:d9:61:4d, 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 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: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:aa:aa:aa:aa:aa:0c, vlan:0)