INFO: task syz.4.70:6144 blocked for more than 143 seconds.
      Not tainted 6.13.0-syzkaller-04058-g05d91cdb1f91 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.70        state:D stack:24128 pid:6144  tgid:6144  ppid:5829   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5373 [inline]
 __schedule+0x186c/0x4be0 kernel/sched/core.c:6760
 __schedule_loop kernel/sched/core.c:6837 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6852
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6909
 __mutex_lock_common kernel/locking/mutex.c:662 [inline]
 __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730
 tun_detach drivers/net/tun.c:702 [inline]
 tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3521
 __fput+0x23c/0xa50 fs/file_table.c:450
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efc0718cd29
RSP: 002b:00007ffff13474f8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007efc073a7ba0 RCX: 00007efc0718cd29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007efc073a7ba0 R08: 00000000000001d0 R09: 00007ffff13477ef
R10: 00000000003ffc0c R11: 0000000000000246 R12: 0000000000017032
R13: 00007efc073a6160 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:1/12:
1 lock held by khungtaskd/30:
 #0: ffffffff8e93a3e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e93a3e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e93a3e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
3 locks held by kworker/1:1/60:
1 lock held by klogd/5196:
2 locks held by udevd/5207:
2 locks held by dhcpcd/5500:
4 locks held by dhcpcd/5501:
2 locks held by getty/5590:
 #0: ffff88814d2040a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5819:
5 locks held by syz-executor/5829:
4 locks held by udevd/5830:
2 locks held by syz-executor/5831:
 #0: ffffffff8fcc5a88 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:702 [inline]
 #0: ffffffff8fcc5a88 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3521
 #1: ffffffff8e93f8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline]
 #1: ffffffff8e93f8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:996
2 locks held by syz-executor/5834:
2 locks held by syz-executor/5835:
5 locks held by syz-executor/5842:
3 locks held by syz-executor/6160:
3 locks held by kworker/1:7/6162:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-04058-g05d91cdb1f91 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
 watchdog+0xff6/0x1040 kernel/hung_task.c:397
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5196 Comm: klogd Not tainted 6.13.0-syzkaller-04058-g05d91cdb1f91 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:32 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:87 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:123 [inline]
RIP: 0010:lock_release+0x19d/0xa30 kernel/locking/lockdep.c:5868
Code: 3b 00 74 08 4c 89 f7 e8 b1 f7 8a 00 4c 89 6c 24 50 48 c7 84 24 b0 00 00 00 00 00 00 00 9c 8f 84 24 b0 00 00 00 42 80 3c 3b 00 <74> 08 4c 89 f7 e8 99 f6 8a 00 48 8b 9c 24 b0 00 00 00 fa 48 c7 c7
RSP: 0018:ffffc90003447320 EFLAGS: 00000246
RAX: ffffffff93e65710 RBX: 1ffff92000688e7a RCX: ffffffff817b0a30
RDX: 0000000000000000 RSI: ffffffff8c601480 RDI: ffffffff8c601440
RBP: ffffc90003447448 R08: ffffffff901ba4b7 R09: 1ffffffff2037496
R10: dffffc0000000000 R11: fffffbfff2037497 R12: 1ffff92000688e70
R13: ffffffff81f77e39 R14: ffffc900034473d0 R15: dffffc0000000000
FS:  00007fd90e49d380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4dd3b762d8 CR3: 000000007dd72000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 free_unref_page+0x719/0x1010 mm/page_alloc.c:2683
 discard_slab mm/slub.c:2688 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3157
 put_cpu_partial+0x17c/0x250 mm/slub.c:3232
 __slab_free+0x290/0x380 mm/slub.c:4483
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:385
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4298 [inline]
 __kmalloc_node_track_caller_noprof+0x28b/0x4c0 mm/slub.c:4317
 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609
 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678
 alloc_skb include/linux/skbuff.h:1331 [inline]
 alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2897
 unix_dgram_sendmsg+0x5f1/0x1df0 net/unix/af_unix.c:2017
 sock_sendmsg_nosec net/socket.c:713 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:728
 __sys_sendto+0x363/0x4c0 net/socket.c:2182
 __do_sys_sendto net/socket.c:2189 [inline]
 __se_sys_sendto net/socket.c:2185 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2185
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd90e5ff9b5
Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc6be2dc38 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd90e5ff9b5
RDX: 000000000000004f RSI: 000055cb8057d310 RDI: 0000000000000003
RBP: 000055cb80578910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013
R13: 00007fd90e78d212 R14: 00007ffc6be2dd38 R15: 0000000000000000
 </TASK>