INFO: task syz.0.1671:5252 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1671 state:D stack:0 pid:5252 tgid:5246 ppid:294 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_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
flush_rcu_work+0x71/0x90 kernel/workqueue.c:4292
kvfree_rcu_barrier+0x23c/0x2f0 kernel/rcu/tree.c:3955
kmem_cache_destroy+0x32/0x170 mm/slab_common.c:490
p9_client_destroy+0x42b/0x480 net/9p/client.c:1088
v9fs_session_close+0x52/0x1d0 fs/9p/v9fs.c:506
v9fs_kill_super+0x60/0x90 fs/9p/vfs_super.c:196
deactivate_locked_super+0xd8/0x2a0 fs/super.c:476
deactivate_super+0xb8/0xe0 fs/super.c:509
cleanup_mnt+0x3f1/0x480 fs/namespace.c:1370
__cleanup_mnt+0x1d/0x40 fs/namespace.c:1377
task_work_run+0x1e3/0x250 kernel/task_work.c:240
resume_user_mode_work+0x36/0x50 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+0x64/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f776cf8ebe9
RSP: 002b:00007f776dd66038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: fffffffffffffffe RBX: 00007f776d1c6090 RCX: 00007f776cf8ebe9
RDX: 00002000000003c0 RSI: 0000200000000500 RDI: 0000000000000000
RBP: 00007f776d011e19 R08: 0000200000000200 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f776d1c6128 R14: 00007f776d1c6090 R15: 00007fff0f54ed68
INFO: task syz.5.1676:5266 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1676 state:D stack:0 pid:5266 tgid:5264 ppid:2962 flags:0x00004006
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
rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589
flush_rcu_work+0x71/0x90 kernel/workqueue.c:4292
kvfree_rcu_barrier+0x23c/0x2f0 kernel/rcu/tree.c:3955
kmem_cache_destroy+0x32/0x170 mm/slab_common.c:490
p9_client_destroy+0x42b/0x480 net/9p/client.c:1088
v9fs_session_close+0x52/0x1d0 fs/9p/v9fs.c:506
v9fs_kill_super+0x60/0x90 fs/9p/vfs_super.c:196
deactivate_locked_super+0xd8/0x2a0 fs/super.c:476
v9fs_mount+0x764/0xa00 fs/9p/vfs_super.c:177
legacy_get_tree+0x103/0x1b0 fs/fs_context.c:662
vfs_get_tree+0xa1/0x290 fs/super.c:1817
do_new_mount+0x251/0xb40 fs/namespace.c:3531
path_mount+0x688/0x1050 fs/namespace.c:3858
do_mount fs/namespace.c:3871 [inline]
__do_sys_mount fs/namespace.c:4081 [inline]
__se_sys_mount+0x2bd/0x480 fs/namespace.c:4058
__x64_sys_mount+0xc3/0xf0 fs/namespace.c:4058
x64_sys_call+0x2021/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:166
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: 0033:0x7f9ac638ebe9
RSP: 002b:00007f9ac7170038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9ac65c6090 RCX: 00007f9ac638ebe9
RDX: 00002000000003c0 RSI: 0000200000000500 RDI: 0000000000000000
RBP: 00007f9ac6411e19 R08: 0000200000000200 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9ac65c6128 R14: 00007f9ac65c6090 R15: 00007fff51dedbd8
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 3f7d833acb9715dc4d925f14855ea176aa3f9a02
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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+0x2c7/0x370 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: 5342 Comm: syz-executor Not tainted syzkaller #0 3f7d833acb9715dc4d925f14855ea176aa3f9a02
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:stack_depot_save_flags+0x3bd/0x800 lib/stackdepot.c:679
Code: a0 e8 17 ca b1 02 48 85 db 74 0d 48 89 df be 02 00 00 00 e8 f5 8e f9 fe 4d 85 ed 74 2b 41 8b 45 18 65 48 8b 0c 25 28 00 00 00 <48> 3b 4d d0 0f 85 11 03 00 00 48 83 c4 38 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc900000075f0 EFLAGS: 00000286
RAX: 00000000016a0210 RBX: 0000000000000000 RCX: c7ceb85f4fdf4c00
RDX: ffff8881f60c8390 RSI: 0000000000000001 RDI: 000000002d4c991e
RBP: ffffc90000007650 R08: 000000000fffe982 R09: 000000000a088c78
R10: 000000000000000e R11: ffffffff817441e0 R12: 000000004b1ec839
R13: ffff88811e480b50 R14: ffffc90000007660 R15: 000000000000000e
FS: 0000555580720500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1b6efc3650 CR3: 00000001807b6000 CR4: 00000000003526b0
Call Trace:
kasan_save_stack mm/kasan/common.c:49 [inline]
kasan_save_track+0x4f/0x80 mm/kasan/common.c:69
kasan_save_free_info+0x4a/0x60 mm/kasan/generic.c:579
poison_slab_object mm/kasan/common.c:248 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:265
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2418 [inline]
slab_free mm/slub.c:4672 [inline]
kmem_cache_free+0x1c1/0x510 mm/slub.c:4779
kfree_skbmem net/core/skbuff.c:-1 [inline]
__kfree_skb+0x18f/0x210 net/core/skbuff.c:1203
consume_skb+0x65/0x1a0 net/core/skbuff.c:1434
arp_process+0xd79/0x1740 net/ipv4/arp.c:941
NF_HOOK+0x157/0x1b0 include/linux/netfilter.h:317
arp_rcv+0x2f8/0x490 net/ipv4/arp.c:991
__netif_receive_skb_one_core net/core/dev.c:5757 [inline]
__netif_receive_skb net/core/dev.c:5870 [inline]
process_backlog+0x556/0xae0 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
__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:3951
addrconf_notify+0x17a/0xea0 net/ipv6/addrconf.c:-1
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]
unregister_netdevice_many_notify+0xe32/0x1bd0 net/core/dev.c:11489
unregister_netdevice_many+0x1d/0x30 net/core/dev.c:11551
setup_net+0x5cc/0x990 net/core/net_namespace.c:383
copy_net_ns+0x513/0xa30 net/core/net_namespace.c:510
create_new_namespaces+0x3b5/0x720 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x126/0x180 kernel/nsproxy.c:228
ksys_unshare+0x4fe/0x880 kernel/fork.c:3352
__do_sys_unshare kernel/fork.c:3423 [inline]
__se_sys_unshare kernel/fork.c:3421 [inline]
__x64_sys_unshare+0x3c/0x50 kernel/fork.c:3421
x64_sys_call+0x2998/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:273
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: 0033:0x7fe8059903e7
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff4d8ab938 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fe805bc5f40 RCX: 00007fe8059903e7
RDX: 0000000000000005 RSI: 00007fff4d8ab800 RDI: 0000000040000000
RBP: 00007fe805bc67b8 R08: 00007fe8066f7d60 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
net_ratelimit: 116250 callbacks suppressed
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:c2:f0:0b:95:75:bf, 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: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: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)