INFO: task syz.0.17:5323 blocked for more than 143 seconds.
      Not tainted 5.15.189-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:27872 pid: 5323 ppid:  4960 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
 rwsem_down_read_slowpath+0x528/0x990 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x96/0x2e0 kernel/locking/rwsem.c:1500
 user_get_super+0x118/0x240 fs/super.c:850
 quotactl_block fs/quota/quota.c:889 [inline]
 __do_sys_quotactl fs/quota/quota.c:953 [inline]
 __se_sys_quotactl+0x45e/0x6c0 fs/quota/quota.c:915
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7feb7cc96b69
RSP: 002b:00007feb7bee5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007feb7cebe080 RCX: 00007feb7cc96b69
RDX: 0000000000000000 RSI: 0000200000000900 RDI: ffffffff80000600
RBP: 00007feb7cd19df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007feb7cebe080 R15: 00007fff9dbc3c48
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u4:0/9:
 #0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: 
ffffc90000ce7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:1/144:
3 locks held by kworker/1:2/1107:
 #0: ffff8880b913a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffff8880b9127848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891
 #2: ffffffff8c11c3c0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311
2 locks held by getty/3952:
 #0: ffff88802b6ef098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:10/4320:
 #0: ffff88814cd45138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc900034afd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4111
3 locks held by kworker/0:21/4953:
 #0: ffff88814cd45138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc900034ffd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4111
1 lock held by syz.2.19/5102:
1 lock held by syz.0.17/5321:
1 lock held by syz.0.17/5323:
 #0: ffff888078e4c0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz.3.20/5325:
1 lock held by syz.1.18/5331:
1 lock held by syz.4.21/5334:
1 lock held by syz.5.22/5558:
1 lock held by syz.7.24/5863:
1 lock held by syz.6.23/5867:
1 lock held by syz.8.25/5871:
1 lock held by syz.9.26/5875:
1 lock held by syz.2.27/5896:
 #0: ffff888144c160e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz.3.29/5999:
 #0: ffff88801fd0e0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz.0.28/6007:
 #0: ffff888078e4c0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz.4.31/6018:
 #0: ffff888078d0a0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz.1.30/6021:
 #0: ffff8880200620e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz.5.32/6030:
 #0: ffff88805c5aa0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
1 lock held by syz-executor/6062:
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
1 lock held by syz-executor/6072:
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
1 lock held by syz-executor/6081:
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
1 lock held by syz.6.33/6099:
 #0: ffff88801f6100e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850
2 locks held by syz-executor/6133:
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d235f48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647
 #1: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845
1 lock held by syz.7.34/6146:
 #0: ffff888056aee0e0 (&type->s_umount_key#54){.+.+}-{3:3}, at: user_get_super+0x118/0x240 fs/super.c:850

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5558 Comm: syz.5.22 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x5f/0x290 mm/kasan/generic.c:189
Code: 00 00 fc ff df 49 89 fb 49 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4f 8d 0c 03 48 8d 5c 37 ff 48 c1 eb 03 4e 8d 14 3b 4d 89 d6 <4d> 29 ce 49 83 fe 10 7f 26 4d 85 f6 0f 84 39 01 00 00 48 f7 d3 4c
RSP: 0018:ffffc90002fff700 EFLAGS: 00000802
RAX: ffffffff81d59501 RBX: 1ffff1100e01b280 RCX: ffffffff81d595f2
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880700d9400
RBP: ffffc90002fff880 R08: dffffc0000000000 R09: ffffed100e01b280
R10: ffffed100e01b281 R11: 1ffff1100e01b280 R12: 0000000000000000
R13: 0000000000000200 R14: ffffed100e01b281 R15: dffffc0000000001
FS:  00007f2c1d5cb6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8c4cc16e9c CR3: 000000001b3e3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_inc include/linux/atomic/atomic-instrumented.h:181 [inline]
 get_bh include/linux/buffer_head.h:313 [inline]
 lookup_bh_lru fs/buffer.c:1289 [inline]
 __find_get_block+0x682/0x10b0 fs/buffer.c:1306
 __getblk_gfp+0x2c/0xb70 fs/buffer.c:1332
 __bread_gfp+0x28/0x380 fs/buffer.c:1381
 sb_bread include/linux/buffer_head.h:337 [inline]
 exfat_get_dentry+0x598/0x800 fs/exfat/dir.c:742
 exfat_create_upcase_table+0x19b/0xdf0 fs/exfat/nls.c:764
 __exfat_fill_super fs/exfat/super.c:588 [inline]
 exfat_fill_super+0x12b5/0x2cf0 fs/exfat/super.c:644
 get_tree_bdev+0x3f1/0x610 fs/super.c:1325
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3014
 do_mount fs/namespace.c:3357 [inline]
 __do_sys_mount fs/namespace.c:3565 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3542
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2c1e35d30a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 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:00007f2c1d5cae68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f2c1d5caef0 RCX: 00007f2c1e35d30a
RDX: 0000200000001500 RSI: 0000200000000140 RDI: 00007f2c1d5caeb0
RBP: 0000200000001500 R08: 00007f2c1d5caef0 R09: 0000000000000800
R10: 0000000000000800 R11: 0000000000000246 R12: 0000200000000140
R13: 00007f2c1d5caeb0 R14: 00000000000014fe R15: 0000200000003d80
 </TASK>