INFO: task syz-executor:1690 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:1690 tgid:1690 ppid:1 flags:0x00000004 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 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x79e/0xa40 net/core/rtnetlink.c:6672 netlink_rcv_skb+0x256/0x4f0 net/netlink/af_netlink.c:2545 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6693 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x8c3/0xa60 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x7fe/0xb10 net/netlink/af_netlink.c:1889 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x718/0x790 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: 0033:0x7f98ced57817 RSP: 002b:00007ffcd95bd940 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000555579f36500 RCX: 00007f98ced57817 RDX: 0000000000000028 RSI: 00007f98cfb44670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffcd95bd9a4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f98cfb44670 R15: 0000000000000000 INFO: task syz-executor:1691 blocked for more than 124 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:R running task stack:0 pid:1691 tgid:1691 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5996 [inline] __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843 preempt_schedule_irq+0xab/0x110 kernel/sched/core.c:8169 raw_irqentry_exit_cond_resched+0x32/0x40 kernel/entry/common.c:311 irqentry_exit+0x4a/0x60 kernel/entry/common.c:354 sysvec_reschedule_ipi+0x72/0x80 arch/x86/kernel/smp.c:248 asm_sysvec_reschedule_ipi+0x1f/0x30 arch/x86/include/asm/idtentry.h:707 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x5b/0x70 kernel/locking/spinlock.c:194 Code: 4e 87 e8 88 ab 3e fc 4c 89 f7 48 83 3d fd 9c ad 01 00 74 29 e8 d6 0d 00 00 90 f7 c3 00 02 00 00 74 01 fb 65 ff 0d 6d 18 64 7a <74> 0a 5b 41 5e 5d c3 cc cc cc cc cc e8 74 49 69 fb eb ef 0f 0b b8 RSP: 0018:ffffc9001106f3e0 EFLAGS: 00000286 RAX: 0000000000000001 RBX: 0000000000000a06 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000a06 RDI: ffff888102278d98 RBP: ffffc9001106f3f0 R08: ffffea00052c04c7 R09: 1ffffd4000a58098 R10: dffffc0000000000 R11: fffff94000a58099 R12: dffffc0000000000 R13: ffffc9001106f6b8 R14: ffffc9001106f5c0 R15: 000000000000001f spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1592 [inline] folios_put_refs+0x77b/0x8f0 mm/swap.c:1053 free_pages_and_swap_cache+0x2fd/0x5e0 mm/swap_state.c:336 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x79a/0xac0 mm/mmu_gather.c:373 tlb_finish_mmu+0xcf/0x1d0 mm/mmu_gather.c:465 exit_mmap+0x445/0xbc0 mm/mmap.c:1976 __mmput+0x93/0x320 kernel/fork.c:1353 mmput+0x55/0x170 kernel/fork.c:1376 exit_mm kernel/exit.c:574 [inline] do_exit+0x93f/0x2650 kernel/exit.c:940 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: 0033:0x7f15edd57817 RSP: 002b:00007ffe056ecdd0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: 0000000000000028 RBX: 0000555577097500 RCX: 00007f15edd57817 RDX: 0000000000000028 RSI: 00007f15eeb44670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe056ece34 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f15eeb44670 R15: 0000000000000000 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 ec67a0b9c3f9090985a335a00964337a606b4ed6 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+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 ec67a0b9c3f9090985a335a00964337a606b4ed6 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline] RIP: 0010:update_stack_state+0x1c4/0x4b0 arch/x86/kernel/unwind_frame.c:228 Code: 48 8b bd 70 ff ff ff e8 2a b2 9a 00 4c 8b 73 10 48 8b 45 b8 42 0f b6 04 28 84 c0 0f 85 8c 00 00 00 49 89 dc 44 8b 2b 45 85 ed <0f> 95 c0 48 8b 55 b0 4c 39 fa 0f 93 c1 20 c1 4c 39 f2 0f 92 c0 20 RSP: 0018:ffffc90000007418 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffffc90000007568 RCX: 1ffff92000000eaf RDX: 1ffff92000000eb0 RSI: 1ffff92000000eae RDI: ffffc900000075c0 RBP: ffffc900000074d8 R08: ffffc90000007630 R09: ffffc90000007628 R10: 0000000000000009 R11: ffffffff8175cab0 R12: ffffc90000007568 R13: 0000000000000002 R14: ffffc90000008000 R15: ffffc90000000000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdf1d51fec CR3: 000000010c79a000 CR4: 00000000003526b0 Call Trace: unwind_next_frame+0x3c1/0x750 arch/x86/kernel/unwind_frame.c:315 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_free_info+0x4a/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:249 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2445 [inline] slab_free mm/slub.c:4714 [inline] kmem_cache_free+0x1bd/0x4f0 mm/slub.c:4821 kfree_skbmem net/core/skbuff.c:-1 [inline] __kfree_skb+0x18f/0x210 net/core/skbuff.c:1203 sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240 kfree_skb_reason include/linux/skbuff.h:1271 [inline] kfree_skb include/linux/skbuff.h:1280 [inline] ip6_mc_input+0x516/0x6c0 net/ipv6/ip6_input.c:587 dst_input include/net/dst.h:469 [inline] ip6_rcv_finish+0x360/0x3e0 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:317 [inline] ipv6_rcv+0xf1/0x240 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5776 [inline] __netif_receive_skb net/core/dev.c:5889 [inline] process_backlog+0x44b/0xad0 net/core/dev.c:6225 __napi_poll+0xd0/0x610 net/core/dev.c:6876 napi_poll net/core/dev.c:6945 [inline] net_rx_action+0x5ea/0xd80 net/core/dev.c:7067 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+0x64/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 110367 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:ca:b6:a7:b3:6f:20, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:ca:b6:a7:b3:6f:20, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) net_ratelimit: 134366 callbacks suppressed bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:ca:b6:a7:b3:6f:20, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:ca:b6:a7:b3:6f:20, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:ca:b6:a7:b3:6f:20, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)