INFO: task syz-executor:435 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:435 tgid:435 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:6052 [inline] __schedule+0x1496/0x20b0 kernel/sched/core.c:7865 __schedule_loop kernel/sched/core.c:7942 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7957 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8014 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x902/0x1b90 kernel/locking/mutex.c:806 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1136 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6676 netlink_rcv_skb+0x24a/0x4e0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6697 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8bf/0xa70 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7d1/0xad0 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x68a/0x700 net/socket.c:2216 __do_sys_sendto net/socket.c:2228 [inline] __se_sys_sendto net/socket.c:2224 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2224 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f7a3cf58fd7 RSP: 002b:00007ffe17a2f120 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000055557ab03500 RCX: 00007f7a3cf58fd7 RDX: 0000000000000028 RSI: 00007f7a3dd54670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe17a2f184 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f7a3dd54670 R15: 0000000000000000 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 35c7ec5060a775d4d4f6b490df0454f0e9b62d01 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+0xe45/0xf90 kernel/hung_task.c:423 kthread+0x2c7/0x360 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 17 Comm: ksoftirqd/0 Not tainted syzkaller #0 35c7ec5060a775d4d4f6b490df0454f0e9b62d01 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__skb_queue_before include/linux/skbuff.h:2418 [inline] RIP: 0010:__skb_queue_tail include/linux/skbuff.h:2451 [inline] RIP: 0010:enqueue_to_backlog+0x681/0xb80 net/core/dev.c:5015 Code: 4d d0 4c 8d b9 c0 0f 05 00 0f 85 8a 04 00 00 80 3b 01 75 07 e8 c0 fb 05 fd eb 0f e8 b9 fb 05 fd bf 03 00 00 00 e8 9f 20 cf fc <49> 8d 9f f8 00 00 00 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 RSP: 0018:ffffc90000116e00 EFLAGS: 00000046 RAX: ffffffff848172d3 RBX: 0000000000000002 RCX: ffff888103652600 RDX: 0000000000000100 RSI: 0000000000000002 RDI: 0000000000000000 RBP: ffffc90000116e90 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff52000022dac R12: dffffc0000000000 R13: 1ffff1102c06a47a R14: ffff8881603523c0 R15: ffff8881f6e50fc0 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb13da26038 CR3: 000000010c372000 CR4: 00000000003526b0 Call Trace: netif_rx_internal+0xab/0x330 net/core/dev.c:5325 __netif_rx+0x24/0x230 net/core/dev.c:5345 veth_forward_skb drivers/net/veth.c:324 [inline] veth_xmit+0x420/0xb30 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+0xfc1/0x3a70 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 run_ksoftirqd+0x20/0x30 kernel/softirq.c:999 smpboot_thread_fn+0x483/0x8b0 kernel/smpboot.c:164 kthread+0x2c7/0x360 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: 111863 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:5a:56:19:2b:0e: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: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:5a:56:19:2b:0e: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 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:5a:56:19:2b:0e:52, vlan:0)