INFO: task syz.3.281:5282 blocked for more than 144 seconds.
      Not tainted 5.15.177-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.281       state:D stack:25880 pid: 5282 ppid:  4170 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 iterate_supers+0xac/0x1e0 fs/super.c:716
 ksys_sync+0xb9/0x1c0 fs/sync.c:102
 __do_sys_sync+0xa/0x10 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f492be4ada9
RSP: 002b:00007f4929cb4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f492c063fa0 RCX: 00007f492be4ada9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f492c063fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f492c063fa0 R15: 00007fff9b7d45e8
 </TASK>
INFO: task syz.0.305:5371 blocked for more than 146 seconds.
      Not tainted 5.15.177-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.305       state:D stack:25208 pid: 5371 ppid:  4166 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 iterate_supers+0xac/0x1e0 fs/super.c:716
 quota_sync_all fs/quota/quota.c:68 [inline]
 __do_sys_quotactl fs/quota/quota.c:936 [inline]
 __se_sys_quotactl+0x347/0x770 fs/quota/quota.c:915
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f38183f9da9
RSP: 002b:00007f3816263038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f3818612fa0 RCX: 00007f38183f9da9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007f381847b2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3818612fa0 R15: 00007ffd9e294998
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by udevd/3545:
 #0: ffff8880b8f3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffffffff8cb1fce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
2 locks held by getty/3920:
 #0: ffff88807f003098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900026362e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
2 locks held by kworker/1:3/4157:
 #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90002e2fd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
1 lock held by syz-executor/4167:
 #0: ffff8880625fa0e0 (&type->s_umount_key#54){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
3 locks held by kworker/1:5/4213:
 #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc9000315fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8cb242a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #2: ffffffff8cb242a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
1 lock held by syz.3.281/5282:
 #0: ffff8880625fa0e0 (&type->s_umount_key#54){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:716
1 lock held by syz.0.305/5371:
 #0: ffff8880625fa0e0 (&type->s_umount_key#54){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:716
1 lock held by syz.2.622/6556:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4178 Comm: syz-executor Not tainted 5.15.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:qlist_free_all+0x2e/0x90 mm/kasan/quarantine.c:176
Code: 41 55 41 54 53 4c 8b 2f 4d 85 ed 74 6e 49 89 f7 49 89 fe 49 bc 00 00 00 00 00 ea ff ff eb 1b 48 ff c9 48 8b 71 18 49 8b 5d 00 <4c> 89 ef e8 3a 04 00 00 49 89 dd 48 85 db 74 2a 4c 89 fe 4d 85 ff
RSP: 0018:ffffc90002f7faa0 EFLAGS: 00000286
RAX: ffffea0000ac9fc0 RBX: ffff88805a3fb300 RCX: ffffea0000ac9fc0
RDX: 0000000000000000 RSI: ffff888017441500 RDI: 0000000000000000
RBP: ffff8880609b9858 R08: ffffffff8139ad58 R09: fffffbfff1c150de
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea0000000000
R13: ffff88802b27f900 R14: ffffc90002f7fad0 R15: 0000000000000000
FS:  000055555d4a4500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe3f4b6dec CR3: 0000000064111000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 getname_flags+0xb8/0x4e0 fs/namei.c:138
 user_path_at_empty+0x2a/0x180 fs/namei.c:2882
 user_path_at include/linux/namei.h:57 [inline]
 ksys_umount fs/namespace.c:1779 [inline]
 __do_sys_umount fs/namespace.c:1787 [inline]
 __se_sys_umount fs/namespace.c:1785 [inline]
 __x64_sys_umount+0xf0/0x170 fs/namespace.c:1785
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f84003470d7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3f4b6dd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f84003c708c RCX: 00007f84003470d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3f4b7f20
RBP: 00007ffe3f4b7f0c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3f4b7f20
R13: 00007f84003c708c R14: 000000000005a0ec R15: 00007ffe3f4b7f60
 </TASK>