INFO: task syz.0.1353:4456 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1353 state:D stack:0 pid:4456 tgid:4455 ppid:290 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
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+0x9e/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: 0033:0x7efefa58ebe9
RSP: 002b:00007efefb350038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007efefa7c5fa0 RCX: 00007efefa58ebe9
RDX: 0000200000000040 RSI: 0000200000000000 RDI: 0000000000000000
RBP: 00007efefa611e19 R08: 00002000000003c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efefa7c6038 R14: 00007efefa7c5fa0 R15: 00007ffe7e7be9a8
INFO: task syz.4.1356:4466 blocked for more than 125 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1356 state:D stack:0 pid:4466 tgid:4465 ppid:1812 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
rcu_barrier+0x4d/0x530 kernel/rcu/tree.c:4589
flush_rcu_work+0x71/0x90 kernel/workqueue.c:4292
kvfree_rcu_barrier+0x18c/0x2f0 kernel/rcu/tree.c:3936
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: 0033:0x7f668358ebe9
RSP: 002b:00007f6684335038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: fffffffffffffffe RBX: 00007f66837c5fa0 RCX: 00007f668358ebe9
RDX: 0000200000000080 RSI: 00002000000002c0 RDI: 0000000000000000
RBP: 00007f6683611e19 R08: 0000200000000400 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f66837c6038 R14: 00007f66837c5fa0 R15: 00007ffc9a086d08
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 cbcc7fb1a3c48ec238a6a34dd578fa775d2dddba
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 98 Comm: klogd Not tainted syzkaller #0 cbcc7fb1a3c48ec238a6a34dd578fa775d2dddba
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:discard_slab mm/slub.c:2760 [inline]
RIP: 0010:__put_partials+0x113/0x150 mm/slub.c:3229
Code: 0d b6 03 48 8b 75 d0 48 85 f6 74 2e 48 8b 5e 10 0f b7 46 2a 25 ff 7f 00 00 49 8b 8e f8 00 00 00 f0 48 ff 49 20 f0 48 29 41 28 <4c> 89 f7 e8 f5 08 00 00 48 89 de 48 85 db 75 d2 48 83 c4 20 5b 41
RSP: 0018:ffffc900007df630 EFLAGS: 00000216
RAX: 000000000000000c RBX: ffffea00051c1ec0 RCX: ffff88810664a400
RDX: dffffc0000000000 RSI: ffffea00051c1f00 RDI: ffff8881f6f72280
RBP: ffffc900007df678 R08: ffff8881f6f72280 R09: 1ffff1103edee450
R10: 1ffff1103edee453 R11: 0000000000000fd8 R12: ffffea00051c1f50
R13: ffff88810664a400 R14: ffff888106649dc0 R15: 0000000000000000
FS: 00007f31be076c80(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559a90b52b98 CR3: 000000010c31c000 CR4: 00000000003526b0
Call Trace:
put_cpu_partial+0x91/0xc0 mm/slub.c:3304
__slab_free+0x1d3/0x2b0 mm/slub.c:4542
do_slab_free mm/slub.c:4624 [inline]
___cache_free+0xc9/0xe0 mm/slub.c:4735
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0xb5/0x130 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x14f/0x180 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x28/0x90 mm/kasan/common.c:330
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4169 [inline]
slab_alloc_node mm/slub.c:4218 [inline]
__do_kmalloc_node mm/slub.c:4356 [inline]
__kmalloc_node_track_caller_noprof+0x154/0x440 mm/slub.c:4376
kmalloc_reserve+0x144/0x500 net/core/skbuff.c:618
__alloc_skb+0x144/0x370 net/core/skbuff.c:687
alloc_skb include/linux/skbuff.h:1331 [inline]
alloc_skb_with_frags+0xce/0x8b0 net/core/skbuff.c:6609
sock_alloc_send_pskb+0x858/0x990 net/core/sock.c:2902
unix_dgram_sendmsg+0x59a/0x1b70 net/unix/af_unix.c:2038
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x66a/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: 0033:0x7f31be1c6407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffea723bbd0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f31be076c80 RCX: 00007f31be1c6407
RDX: 000000000000005b RSI: 00007ffea723bd10 RDI: 0000000000000003
RBP: 00007ffea723c140 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffea723c158
R13: 00007ffea723bd10 R14: 0000000000000040 R15: 00007ffea723bd10
net_ratelimit: 84732 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 veth0_to_bridge with own address as source address (addr:86:d7:ad:96:a1:d6, 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:86:d7:ad:96:a1:d6, 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:86:d7:ad:96:a1:d6, 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:86:d7:ad:96:a1:d6, 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:86:d7:ad:96:a1:d6, vlan:0)