INFO: task syz.6.1514:19902 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1514 state:D stack:28328 pid:19902 tgid:19897 ppid:17243 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760
expkey_flush+0x20/0x90 fs/nfsd/export.c:250
write_flush.constprop.0+0x2af/0x3d0 net/sunrpc/cache.c:1550
pde_write fs/proc/inode.c:330 [inline]
proc_reg_write+0x240/0x330 fs/proc/inode.c:342
do_loop_readv_writev fs/read_write.c:850 [inline]
do_loop_readv_writev fs/read_write.c:835 [inline]
vfs_writev+0x5df/0xde0 fs/read_write.c:1059
do_writev+0x132/0x340 fs/read_write.c:1103
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f86a298efc9
RSP: 002b:00007f86a0bf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f86a2be6090 RCX: 00007f86a298efc9
RDX: 000000000000000a RSI: 0000200000000200 RDI: 0000000000000002
RBP: 00007f86a2a11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f86a2be6128 R14: 00007f86a2be6090 R15: 00007ffefdf4b9d8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c42e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c42e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c42e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
5 locks held by kworker/u10:8/7318:
3 locks held by kworker/u10:37/10506:
#0: ffff88813ff29948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1: ffffc9000d5d7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2: ffffffff900fcf48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:303
2 locks held by syz.2.1374/17534:
#0:
ffffffff901a0b10
(
cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ece88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1590
2 locks held by getty/19670:
#0: ffff88814d82d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e632f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
3 locks held by syz.6.1514/19902:
#0: ffff8880325ee478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1232
#1: ffff88803318a420 (sb_writers#3){.+.+}-{0:0}, at: do_writev+0x132/0x340 fs/read_write.c:1103
#2: ffffffff8e7ece88 (nfsd_mutex){+.+.}-{4:4}, at: expkey_flush+0x20/0x90 fs/nfsd/export.c:250
2 locks held by syz.5.1620/21423:
#0: ffff88804f9aa0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88804f9aa0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88804f9aa0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline]
#0: ffff88804f9aa0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:502
#1: ffffffff8e7ece88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:593
1 lock held by syz.5.1620/21433:
#0: ffff88804f9aa0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88804f9aa0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: super_lock+0x17d/0x3f0 fs/super.c:121
1 lock held by syz-executor/21994:
#0: ffffffff8e3cf878 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by syz.8.1692/22598:
#0: ffffffff901a0b10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e7ece88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x687/0xbc0 fs/nfsd/nfsctl.c:1590
2 locks held by syz-executor/22762:
#0: ffff88809db2c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88809db2c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88809db2c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline]
#0: ffff88809db2c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:502
#1: ffffffff8e7ece88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:593
2 locks held by syz-executor/25478:
#0: ffffffff8f4a6000 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#0: ffffffff8f4a6000 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#0: ffffffff8f4a6000 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:574
#1: ffffffff900fcf48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff900fcf48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff900fcf48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x600/0x2000 net/core/rtnetlink.c:4064
2 locks held by syz.1.1829/25692:
#0: ffff88805c0920e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88805c0920e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88805c0920e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline]
#0: ffff88805c0920e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:502
#1: ffffffff8e7ece88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:593
2 locks held by syz.0.1830/25744:
#0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576
#1: ffffffff900fcf48 (rtnl_mutex){+.+.}-{4:4}, at: mpls_net_exit+0x83/0x350 net/mpls/af_mpls.c:2706
2 locks held by syz.0.1830/25745:
#0: ffffffff900e6b30 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x2d6/0x690 net/core/net_namespace.c:576
#1:
ffffffff900fcf48
(
rtnl_mutex
){+.+.}-{4:4}
, at: cangw_pernet_exit_batch+0x15/0xa0 net/can/gw.c:1288
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf3f/0x1170 kernel/hung_task.c:495
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7318 Comm: kworker/u10:8 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: xprtiod xs_tcp_setup_socket
RIP: 0010:memcpy_orig+0x21/0x130 arch/x86/lib/memcpy_64.S:69
Code: 90 90 90 90 90 90 90 90 90 48 89 f8 48 83 fa 20 72 7e 40 38 fe 7c 35 48 83 ea 20 48 83 ea 20 4c 8b 06 4c 8b 4e 08 4c 8b 56 10 <4c> 8b 5e 18 48 8d 76 20 4c 89 07 4c 89 4f 08 4c 89 57 10 4c 89 5f
RSP: 0018:ffffc90004d77510 EFLAGS: 00000206
RAX: ffffc90004d77788 RBX: ffffffff8e346bf0 RCX: ffffffff819c607d
RDX: 0000000000000018 RSI: ffffffff8e346bf0 RDI: ffffc90004d77788
RBP: ffffc90004d77788 R08: 0000000000003556 R09: 000000a9df3602f2
R10: 0000001f82000020 R11: 00000000000a0228 R12: 000000000000000d
R13: 0000000000003556 R14: ffffffff8e2d15e0 R15: ffffc90004d775e8
FS: 0000000000000000(0000) GS:ffff8881249e1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9a62d38e9c CR3: 0000000078046000 CR4: 00000000003526f0
Call Trace:
prb_read kernel/printk/printk_ringbuffer.c:1951 [inline]
_prb_read_valid+0x25d/0x890 kernel/printk/printk_ringbuffer.c:2131
prb_read_valid+0x78/0xa0 kernel/printk/printk_ringbuffer.c:2203
printk_get_next_message+0x15b/0x6d0 kernel/printk/printk.c:2978
console_emit_next_record kernel/printk/printk.c:3065 [inline]
console_flush_all+0x6ea/0xc60 kernel/printk/printk.c:3199
__console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
console_unlock+0xd8/0x210 kernel/printk/printk.c:3298
vprintk_emit+0x3d7/0x680 kernel/printk/printk.c:2423
_printk+0xc7/0x100 kernel/printk/printk.c:2448
xs_tcp_setup_socket+0x417/0xe50 net/sunrpc/xprtsock.c:2490
process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3263
process_scheduled_works kernel/workqueue.c:3346 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245