INFO: task syz-executor:4357 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:4357 tgid:4357 ppid:1 flags:0x00004004
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_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1889
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: 0033:0x7f1647b90e03
RSP: 002b:00007ffe5ffcf898 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f1648914620 RCX: 00007f1647b90e03
RDX: 000000000000002c RSI: 00007f1648914670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffe5ffcf8b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f1648914670 R15: 0000000000000000
INFO: task syz-executor:4358 blocked for more than 125 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:4358 tgid:4358 ppid:1 flags:0x00000004
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_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x8c0/0xa60 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1889
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: 0033:0x7fbee9b90e03
RSP: 002b:00007ffcb444a588 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fbeea914620 RCX: 00007fbee9b90e03
RDX: 000000000000002c RSI: 00007fbeea914670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffcb444a5a4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fbeea914670 R15: 0000000000000000
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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+0x2ca/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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 330 Comm: kworker/u8:4 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: netns cleanup_net
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x87/0x90 kernel/kcov.c:316
Code: 8d 52 28 4d 39 ca 77 22 89 ff 89 f6 49 ff c0 4c 89 01 48 c7 44 11 08 05 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 <5d> c3 cc cc cc cc cc 66 90 b8 c5 9c ba 86 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000230570 EFLAGS: 00000246
RAX: ffffffff85002ad0 RBX: 0000000000000000 RCX: 0000000000000100
RDX: ffff888109790000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000230570 R08: 000000001baaaaaa R09: 1ffff920000460c0
R10: dffffc0000000000 R11: fffff520000460c1 R12: ffff88813120f0c0
R13: 0000000000000000 R14: ffff8881033d8af6 R15: 1ffff1102067b15e
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdaf0df84c0 CR3: 0000000109fa0000 CR4: 00000000003526b0
Call Trace:
__rhashtable_lookup include/linux/rhashtable.h:610 [inline]
rhashtable_lookup include/linux/rhashtable.h:646 [inline]
fdb_find_rcu+0x2d0/0x530 net/bridge/br_fdb.c:223
br_fdb_update+0x109/0x680 net/bridge/br_fdb.c:899
br_handle_frame_finish+0x39c/0x1720 net/bridge/br_input.c:141
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:5663
__netif_receive_skb_one_core net/core/dev.c:5767 [inline]
__netif_receive_skb net/core/dev.c:5882 [inline]
process_backlog+0x3e5/0xae0 net/core/dev.c:6218
__napi_poll+0xd3/0x610 net/core/dev.c:6869
napi_poll net/core/dev.c:6938 [inline]
net_rx_action+0x584/0xce0 net/core/dev.c:7060
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
__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]
addrconf_ifdown+0x608/0x1940 net/ipv6/addrconf.c:3950
addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1
notifier_call_chain+0x10b/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]
unregister_netdevice_many_notify+0xe32/0x1bd0 net/core/dev.c:11501
unregister_netdevice_many net/core/dev.c:11563 [inline]
default_device_exit_batch+0x810/0x8a0 net/core/dev.c:12046
ops_exit_list net/core/net_namespace.c:178 [inline]
cleanup_net+0x72e/0xc70 net/core/net_namespace.c:642
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2ca/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
net_ratelimit: 126419 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:7d:9b:44:2b:c4, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:7d:9b:44:2b:c4, 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:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:7d:9b:44:2b:c4, 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:d6:7d:9b:44:2b:c4, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:7d:9b:44:2b:c4, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:d6:7d:9b:44:2b:c4, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)