syzbot

INFO: task syz.0.3769:11606 blocked for more than 124 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3769      state:D stack:0     pid:11606 tgid:11601 ppid:10043  flags:0x00004006
Call Trace:
 <TASK>
 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
 ppp_release+0xf5/0x200 drivers/net/ppp/ppp_generic.c:422
 __fput+0x1fb/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e3/0x250 kernel/task_work.c:240
 get_signal+0x1307/0x14f0 kernel/signal.c:2706
 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: 0033:0x7fa7c258ebe9
RSP: 002b:00007fa7c33ea038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007fa7c27b6090 RCX: 00007fa7c258ebe9
RDX: 0000200000000080 RSI: 0000000040047451 RDI: 0000000000000004
RBP: 00007fa7c2611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa7c27b6128 R14: 00007fa7c27b6090 R15: 00007ffdd2f770c8
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 a29bcd2d578c4b9493db917853c72486663e8fa1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __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+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11632 Comm: syz-executor Not tainted syzkaller #0 a29bcd2d578c4b9493db917853c72486663e8fa1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__update_page_owner_handle+0xcf/0x370 mm/page_owner.c:262
Code: c4 44 89 ee e8 32 9e a3 ff 45 39 e5 0f 84 5c 02 00 00 4c 8b 2d 02 8f 69 05 4a 8d 7c 2b 08 48 89 f8 48 c1 e8 03 42 0f b6 04 30 <84> c0 0f 85 9e 01 00 00 49 01 dd 8b 45 d0 41 89 45 08 4c 89 e8 48
RSP: 0018:ffffc90000006e38 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffff88810a8fd0e0 RCX: 0000000000000100
RDX: ffff888144824c00 RSI: 0000000000000001 RDI: ffff88810a8fd0f0
RBP: ffffc90000006e98 R08: 00000000ffffffff R09: 0000005e9fdd3f78
R10: ffff888144825450 R11: ffffffff81744340 R12: 0000000000000000
R13: 0000000000000008 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000555570958500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbfc4ae7d60 CR3: 000000015b520000 CR4: 00000000003526b0
DR0: 0000000000000006 DR1: 0000000000000003 DR2: 0000000000000401
DR3: 0000000000000404 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __set_page_owner+0x124/0x5d0 mm/page_owner.c:343
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook+0x3b9/0x3f0 mm/page_alloc.c:1826
 prep_new_page+0x1c/0x120 mm/page_alloc.c:1834
 get_page_from_freelist+0x48ce/0x4960 mm/page_alloc.c:3914
 __alloc_pages_noprof+0x31f/0x7b0 mm/page_alloc.c:5258
 alloc_slab_page+0x6b/0x1f0 mm/slub.c:-1
 allocate_slab+0x69/0x440 mm/slub.c:2660
 new_slab mm/slub.c:2714 [inline]
 ___slab_alloc+0x59a/0x8b0 mm/slub.c:3902
 __slab_alloc mm/slub.c:3992 [inline]
 __slab_alloc_node mm/slub.c:4045 [inline]
 slab_alloc_node mm/slub.c:4206 [inline]
 kmem_cache_alloc_noprof+0x202/0x3a0 mm/slub.c:4227
 skb_clone+0x229/0x460 net/core/skbuff.c:2082
 deliver_clone net/bridge/br_forward.c:125 [inline]
 maybe_deliver net/bridge/br_forward.c:190 [inline]
 br_flood+0x4ed/0x730 net/bridge/br_forward.c:236
 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+0xf48/0x3940 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
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
 _raw_spin_unlock_bh+0x54/0x60 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 fib_create_info+0x190f/0x2170 net/ipv4/fib_semantics.c:1618
 fib_table_insert+0xba/0x1e50 net/ipv4/fib_trie.c:1218
 fib_magic net/ipv4/fib_frontend.c:1118 [inline]
 fib_add_ifaddr+0x9c5/0xd30 net/ipv4/fib_frontend.c:1162
 fib_netdev_event+0x4c6/0x5d0 net/ipv4/fib_frontend.c:1500
 notifier_call_chain+0x10e/0x2c0 kernel/notifier.c:93
 raw_notifier_call_chain+0x31/0x40 kernel/notifier.c:461
 call_netdevice_notifiers_info net/core/dev.c:2067 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2105 [inline]
 call_netdevice_notifiers net/core/dev.c:2119 [inline]
 __dev_notify_flags+0x2d3/0x530 net/core/dev.c:-1
 dev_change_flags+0xe9/0x1a0 net/core/dev.c:9000
 do_setlink+0xc03/0x4010 net/core/rtnetlink.c:2932
 __rtnl_newlink net/core/rtnetlink.c:3728 [inline]
 rtnl_newlink+0x172c/0x2130 net/core/rtnetlink.c:3775
 rtnetlink_rcv_msg+0x87f/0xa00 net/core/rtnetlink.c:6678
 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537
 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline]
 netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342
 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x66d/0x6f0 net/socket.c:2217
 __do_sys_sendto net/socket.c:2229 [inline]
 __se_sys_sendto net/socket.c:2225 [inline]
 __x64_sys_sendto+0xe9/0x100 net/socket.c:2225
 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5c51990a23
Code: 64 89 02 48 c7 c0 ff ff ff ff eb b7 66 2e 0f 1f 84 00 00 00 00 00 90 80 3d 41 7b 1f 00 00 41 89 ca 74 14 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 75 c3 0f 1f 40 00 55 48 83 ec 30 44 89 4c 24
RSP: 002b:00007ffcea161c98 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f5c526e4620 RCX: 00007f5c51990a23
RDX: 000000000000002c RSI: 00007f5c526e4670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffcea161cb4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f5c526e4670 R15: 0000000000000000
 </TASK>
net_ratelimit: 108974 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:56:eb:ea:3e:82:18, 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:0c, 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:aa:aa:aa:aa:aa:0c, 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: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)