[v6.6] possible deadlock in mark_as_free_ex

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syzbot

unread,
Jul 3, 2025, 12:12:30 AMJul 3
to syzkaller...@googlegroups.com
Hello,

syzbot found the following issue on:

HEAD commit: 3f5b4c104b7d Linux 6.6.95
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=118ab770580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b80883c3ded77c16
dashboard link: https://syzkaller.appspot.com/bug?extid=05e6ebe1716156baf6fe
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0efd4e01816e/disk-3f5b4c10.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f7c9d20858cc/vmlinux-3f5b4c10.xz
kernel image: https://storage.googleapis.com/syzbot-assets/18f8dc74ef68/bzImage-3f5b4c10.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+05e6eb...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.6.95-syzkaller #0 Not tainted
------------------------------------------------------
syz.6.14287/6950 is trying to acquire lock:
ffff88805bae4270 (&wnd->rw_lock){++++}-{3:3}, at: mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484

but task is already holding lock:
ffff88805ed277b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:393 [inline]
ffff88805ed277b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs3_setattr+0x6cd/0xb60 fs/ntfs3/file.c:703

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->file.run_lock#2){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
run_unpack_ex+0x7e6/0xba0 fs/ntfs3/run.c:1117
ntfs_read_mft fs/ntfs3/inode.c:401 [inline]
ntfs_iget5+0x22e3/0x3750 fs/ntfs3/inode.c:533
dir_search_u+0x1e0/0x2b0 fs/ntfs3/dir.c:264
ntfs_atomic_open+0x23b/0x520 fs/ntfs3/namei.c:412
atomic_open fs/namei.c:3351 [inline]
lookup_open fs/namei.c:3459 [inline]
open_last_lookups fs/namei.c:3556 [inline]
path_openat+0xf27/0x3190 fs/namei.c:3786
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&wnd->rw_lock){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484
run_deallocate_ex+0x188/0x2e0 fs/ntfs3/attrib.c:122
attr_set_size+0xeb5/0x2c60 fs/ntfs3/attrib.c:754
ntfs_truncate fs/ntfs3/file.c:394 [inline]
ntfs3_setattr+0x78f/0xb60 fs/ntfs3/file.c:703
notify_change+0xb0d/0xe10 fs/attr.c:499
do_truncate+0x19b/0x220 fs/open.c:66
handle_truncate fs/namei.c:3291 [inline]
do_open fs/namei.c:3636 [inline]
path_openat+0x298c/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ni->file.run_lock#2);
lock(&wnd->rw_lock);
lock(&ni->file.run_lock#2);
lock(&wnd->rw_lock);

*** DEADLOCK ***

4 locks held by syz.6.14287/6950:
#0: ffff88802dc2c418 (sb_writers#33){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:403
#1: ffff88805ed279b0 (&sb->s_type->i_mutex_key#36){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805ed279b0 (&sb->s_type->i_mutex_key#36){+.+.}-{3:3}, at: do_truncate+0x187/0x220 fs/open.c:64
#2: ffff88805ed27700 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1120 [inline]
#2: ffff88805ed27700 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:391 [inline]
#2: ffff88805ed27700 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs3_setattr+0x6bc/0xb60 fs/ntfs3/file.c:703
#3: ffff88805ed277b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:393 [inline]
#3: ffff88805ed277b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs3_setattr+0x6cd/0xb60 fs/ntfs3/file.c:703

stack backtrace:
CPU: 1 PID: 6950 Comm: syz.6.14287 Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484
run_deallocate_ex+0x188/0x2e0 fs/ntfs3/attrib.c:122
attr_set_size+0xeb5/0x2c60 fs/ntfs3/attrib.c:754
ntfs_truncate fs/ntfs3/file.c:394 [inline]
ntfs3_setattr+0x78f/0xb60 fs/ntfs3/file.c:703
notify_change+0xb0d/0xe10 fs/attr.c:499
do_truncate+0x19b/0x220 fs/open.c:66
handle_truncate fs/namei.c:3291 [inline]
do_open fs/namei.c:3636 [inline]
path_openat+0x298c/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_openat fs/open.c:1450 [inline]
__se_sys_openat fs/open.c:1445 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1445
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff11918e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007ff119f3d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff1193b5fa0 RCX: 00007ff11918e929
RDX: 0000000000101b81 RSI: 0000200000000180 RDI: ffffffffffffff9c
RBP: 00007ff119210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff1193b5fa0 R15: 00007ffc943946c8
</TASK>


---
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If the report is already addressed, let syzbot know by replying with:
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If you want to overwrite report's subsystems, reply with:
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup

syzbot

unread,
Aug 23, 2025, 5:00:33 PMAug 23
to syzkaller...@googlegroups.com
syzbot has found a reproducer for the following issue on:

HEAD commit: bb9c90ab9c5a Linux 6.6.102
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16baa7bc580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7b989b97a0687b0a
dashboard link: https://syzkaller.appspot.com/bug?extid=05e6ebe1716156baf6fe
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11baa7bc580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/44e2224124c3/disk-bb9c90ab.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/33e0aef7ff42/vmlinux-bb9c90ab.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0515bc436228/bzImage-bb9c90ab.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/6426e0d57da1/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/5c64fcac046d/mount_2.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+05e6eb...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
6.6.102-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.26/5984 is trying to acquire lock:
ffff8880261b2270 (&wnd->rw_lock){++++}-{3:3}, at: mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484

but task is already holding lock:
ffff88805ee001b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:396 [inline]
ffff88805ee001b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs3_setattr+0x6cd/0xb60 fs/ntfs3/file.c:706

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->file.run_lock#2){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
run_unpack_ex+0x7e6/0xba0 fs/ntfs3/run.c:1117
ntfs_read_mft fs/ntfs3/inode.c:401 [inline]
ntfs_iget5+0x22e3/0x3750 fs/ntfs3/inode.c:533
dir_search_u+0x1e0/0x2b0 fs/ntfs3/dir.c:264
ntfs_atomic_open+0x23b/0x520 fs/ntfs3/namei.c:408
atomic_open fs/namei.c:3351 [inline]
lookup_open fs/namei.c:3459 [inline]
open_last_lookups fs/namei.c:3556 [inline]
path_openat+0xf27/0x3190 fs/namei.c:3786
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_creat fs/open.c:1512 [inline]
__se_sys_creat fs/open.c:1506 [inline]
__x64_sys_creat+0x90/0xb0 fs/open.c:1506
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&wnd->rw_lock){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484
run_deallocate_ex+0x188/0x2e0 fs/ntfs3/attrib.c:122
attr_set_size+0xeb5/0x2c60 fs/ntfs3/attrib.c:754
ntfs_truncate fs/ntfs3/file.c:397 [inline]
ntfs3_setattr+0x78f/0xb60 fs/ntfs3/file.c:706
notify_change+0xb0d/0xe10 fs/attr.c:499
do_truncate+0x19b/0x220 fs/open.c:66
handle_truncate fs/namei.c:3291 [inline]
do_open fs/namei.c:3636 [inline]
path_openat+0x298c/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_creat fs/open.c:1512 [inline]
__se_sys_creat fs/open.c:1506 [inline]
__x64_sys_creat+0x90/0xb0 fs/open.c:1506
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ni->file.run_lock#2);
lock(&wnd->rw_lock);
lock(&ni->file.run_lock#2);
lock(&wnd->rw_lock);

*** DEADLOCK ***

4 locks held by syz.0.26/5984:
#0: ffff8880261b4418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:403
#1: ffff88805ee003b0 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805ee003b0 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x187/0x220 fs/open.c:64
#2: ffff88805ee00100 (&ni->ni_lock/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1119 [inline]
#2: ffff88805ee00100 (&ni->ni_lock/5){+.+.}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:394 [inline]
#2: ffff88805ee00100 (&ni->ni_lock/5){+.+.}-{3:3}, at: ntfs3_setattr+0x6bc/0xb60 fs/ntfs3/file.c:706
#3: ffff88805ee001b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:396 [inline]
#3: ffff88805ee001b0 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs3_setattr+0x6cd/0xb60 fs/ntfs3/file.c:706

stack backtrace:
CPU: 0 PID: 5984 Comm: syz.0.26 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484
run_deallocate_ex+0x188/0x2e0 fs/ntfs3/attrib.c:122
attr_set_size+0xeb5/0x2c60 fs/ntfs3/attrib.c:754
ntfs_truncate fs/ntfs3/file.c:397 [inline]
ntfs3_setattr+0x78f/0xb60 fs/ntfs3/file.c:706
notify_change+0xb0d/0xe10 fs/attr.c:499
do_truncate+0x19b/0x220 fs/open.c:66
handle_truncate fs/namei.c:3291 [inline]
do_open fs/namei.c:3636 [inline]
path_openat+0x298c/0x3190 fs/namei.c:3789
do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
do_sys_open fs/open.c:1434 [inline]
__do_sys_creat fs/open.c:1512 [inline]
__se_sys_creat fs/open.c:1506 [inline]
__x64_sys_creat+0x90/0xb0 fs/open.c:1506
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe1b838ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fe1b92c1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fe1b85b5fa0 RCX: 00007fe1b838ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000002c0
RBP: 00007fe1b8411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe1b85b6038 R14: 00007fe1b85b5fa0 R15: 00007fff740da768
</TASK>


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
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syzbot

unread,
Nov 4, 2025, 3:09:35 PM (2 days ago) Nov 4
to syzkaller...@googlegroups.com
syzbot has found a reproducer for the following issue on:

HEAD commit: 0a805b6ea8cd Linux 6.6.116
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10951bcd980000
kernel config: https://syzkaller.appspot.com/x/.config?x=12606d4b8832c7e4
dashboard link: https://syzkaller.appspot.com/bug?extid=05e6ebe1716156baf6fe
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=158cff34580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14951bcd980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/13874446b4b2/disk-0a805b6e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69a5e59e1ade/vmlinux-0a805b6e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/322c0711f976/bzImage-0a805b6e.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/7dba99d49b94/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/c39b73d27859/mount_3.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+05e6eb...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.68/5991 is trying to acquire lock:
ffff88802fa7e270 (&wnd->rw_lock){++++}-{3:3}, at: mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484

but task is already holding lock:
ffff888072a68910 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:396 [inline]
ffff888072a68910 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs3_setattr+0x6cd/0xb60 fs/ntfs3/file.c:706

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->file.run_lock#2){++++}-{3:3}:
down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520
run_unpack_ex+0x7e6/0xba0 fs/ntfs3/run.c:1122
ntfs_read_mft fs/ntfs3/inode.c:401 [inline]
ntfs_iget5+0x22e3/0x3750 fs/ntfs3/inode.c:533
ntfs_dir_emit fs/ntfs3/dir.c:338 [inline]
ntfs_read_hdr+0x7d4/0xc30 fs/ntfs3/dir.c:386
ntfs_readdir+0xaf4/0xe60 fs/ntfs3/dir.c:497
iterate_dir+0x1c2/0x580 fs/readdir.c:106
__do_sys_getdents64 fs/readdir.c:405 [inline]
__se_sys_getdents64+0xe9/0x260 fs/readdir.c:390
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&wnd->rw_lock){++++}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484
run_deallocate_ex+0x188/0x2e0 fs/ntfs3/attrib.c:122
attr_set_size+0xeb5/0x2c60 fs/ntfs3/attrib.c:754
ntfs_truncate fs/ntfs3/file.c:397 [inline]
ntfs3_setattr+0x78f/0xb60 fs/ntfs3/file.c:706
notify_change+0xb0d/0xe10 fs/attr.c:499
do_truncate+0x19b/0x220 fs/open.c:66
vfs_truncate+0x266/0x300 fs/open.c:112
do_sys_truncate+0xe0/0x1a0 fs/open.c:135
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&ni->file.run_lock#2);
lock(&wnd->rw_lock);
lock(&ni->file.run_lock#2);
lock(&wnd->rw_lock);

*** DEADLOCK ***

4 locks held by syz.0.68/5991:
#0: ffff888024e00418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff888072a68b10 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff888072a68b10 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x187/0x220 fs/open.c:64
#2: ffff888072a68860 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1119 [inline]
#2: ffff888072a68860 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:394 [inline]
#2: ffff888072a68860 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs3_setattr+0x6bc/0xb60 fs/ntfs3/file.c:706
#3: ffff888072a68910 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs_truncate fs/ntfs3/file.c:396 [inline]
#3: ffff888072a68910 (&ni->file.run_lock#2){++++}-{3:3}, at: ntfs3_setattr+0x6cd/0xb60 fs/ntfs3/file.c:706

stack backtrace:
CPU: 0 PID: 5991 Comm: syz.0.68 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
mark_as_free_ex+0x3e/0x380 fs/ntfs3/fsntfs.c:2484
run_deallocate_ex+0x188/0x2e0 fs/ntfs3/attrib.c:122
attr_set_size+0xeb5/0x2c60 fs/ntfs3/attrib.c:754
ntfs_truncate fs/ntfs3/file.c:397 [inline]
ntfs3_setattr+0x78f/0xb60 fs/ntfs3/file.c:706
notify_change+0xb0d/0xe10 fs/attr.c:499
do_truncate+0x19b/0x220 fs/open.c:66
vfs_truncate+0x266/0x300 fs/open.c:112
do_sys_truncate+0xe0/0x1a0 fs/open.c:135
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f756958f6c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007ffe4ba67a68 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f75697e5fa0 RCX: 00007f756958f6c9
RDX: 0000000000000000 RSI: 000000000001bf00 RDI: 00002000000000c0
RBP: 00007f7569611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f75697e5fa0 R14: 00007f75697e5fa0 R15: 0000000000000002
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