[v6.6] possible deadlock in run_unpack_ex

[syzbot]

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=11c7e3d4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b80883c3ded77c16
dashboard link: https://syzkaller.appspot.com/bug?extid=84f81a699ba821308b7f
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+84f81a...@syzkaller.appspotmail.com

ntfs3: loop9: Different NTFS sector size (4096) and media sector size (512).
ntfs3: loop9: Failed to initialize $Extend/$Reparse.
ntfs3: loop9: Mark volume as dirty due to NTFS errors
======================================================
WARNING: possible circular locking dependency detected
6.6.95-syzkaller #0 Not tainted
------------------------------------------------------
syz.9.5942/24930 is trying to acquire lock:
ffff8880777ada30 (&ni->file.run_lock#2){++++}-{3:3}, at: run_unpack_ex+0x7e6/0xba0 fs/ntfs3/run.c:1117

but task is already holding lock:
ffff88806b2a8270 (&wnd->rw_lock){++++}-{3:3}, at: run_unpack_ex+0x702/0xba0 fs/ntfs3/run.c:1098

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&wnd->rw_lock){++++}-{3:3}:
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
ntfs_look_for_free_space+0xd4/0x600 fs/ntfs3/fsntfs.c:362
attr_allocate_clusters+0x1c2/0x6d0 fs/ntfs3/attrib.c:159
attr_set_size+0x14a0/0x2c60 fs/ntfs3/attrib.c:575
ntfs_extend_mft+0x163/0x450 fs/ntfs3/fsntfs.c:512
ntfs_look_free_mft+0x5f6/0xd40 fs/ntfs3/fsntfs.c:709
ntfs_create_inode+0x524/0x3680 fs/ntfs3/inode.c:1338
ntfs_atomic_open+0x3f4/0x520 fs/ntfs3/namei.c:434
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 (&ni->file.run_lock#2){++++}-{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_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

other info that might help us debug this:

Possible unsafe locking scenario:

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

*** DEADLOCK ***

4 locks held by syz.9.5942/24930:
#0: ffff888031810418 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:403
#1: ffff888043fbeaf0 (&type->i_mutex_dir_key#15){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff888043fbeaf0 (&type->i_mutex_dir_key#15){++++}-{3:3}, at: open_last_lookups fs/namei.c:3553 [inline]
#1: ffff888043fbeaf0 (&type->i_mutex_dir_key#15){++++}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3786
#2: ffff888043fbe840 (&ni->ni_lock/6){+.+.}-{3:3}, at: ni_lock_dir fs/ntfs3/ntfs_fs.h:1125 [inline]
#2: ffff888043fbe840 (&ni->ni_lock/6){+.+.}-{3:3}, at: ntfs_atomic_open+0x1ec/0x520 fs/ntfs3/namei.c:404
#3: ffff88806b2a8270 (&wnd->rw_lock){++++}-{3:3}, at: run_unpack_ex+0x702/0xba0 fs/ntfs3/run.c:1098

stack backtrace:
CPU: 1 PID: 24930 Comm: syz.9.5942 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_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
RIP: 0033:0x7f152298e929
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:00007f1523866038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1522bb5fa0 RCX: 00007f152298e929
RDX: 0000000000143042 RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f1522a10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000099 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1522bb5fa0 R15: 00007ffe546c0908
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: dbcb8d8e4163 Linux 6.6.100
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14aa0ca2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=293251cfa8d8100
dashboard link: https://syzkaller.appspot.com/bug?extid=84f81a699ba821308b7f
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=178c0f82580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f289bc580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d0b56817a2c3/disk-dbcb8d8e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0d646b2f7fa/vmlinux-dbcb8d8e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e0b752a5011/bzImage-dbcb8d8e.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/bf98646d99a0/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/25fc4f823d12/mount_2.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+84f81a...@syzkaller.appspotmail.com

ntfs3: loop2: Different NTFS sector size (4096) and media sector size (512).
ntfs3: loop2: Mark volume as dirty due to NTFS errors
ntfs3: loop2: Failed to initialize $Extend/$Reparse.

======================================================
WARNING: possible circular locking dependency detected

6.6.100-syzkaller #0 Not tainted
------------------------------------------------------
syz.2.28/5999 is trying to acquire lock:
ffff88804ac7e190 (&ni->file.run_lock#2){++++}-{3:3}, at: run_unpack_ex+0x7e6/0xba0 fs/ntfs3/run.c:1117

but task is already holding lock:

ffff88807fac8270 (&wnd->rw_lock){++++}-{3:3}, at: run_unpack_ex+0x702/0xba0 fs/ntfs3/run.c:1098

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&wnd->rw_lock){++++}-{3:3}:
down_write_nested+0x9e/0x1f0 kernel/locking/rwsem.c:1689
ntfs_look_for_free_space+0xd4/0x600 fs/ntfs3/fsntfs.c:362
attr_allocate_clusters+0x1c2/0x6d0 fs/ntfs3/attrib.c:159
attr_set_size+0x14a0/0x2c60 fs/ntfs3/attrib.c:575
ntfs_extend_mft+0x163/0x450 fs/ntfs3/fsntfs.c:512
ntfs_look_free_mft+0x5f6/0xd40 fs/ntfs3/fsntfs.c:709
ntfs_create_inode+0x524/0x3680 fs/ntfs3/inode.c:1338

ntfs_symlink+0xda/0x120 fs/ntfs3/namei.c:208
vfs_symlink+0x138/0x2b0 fs/namei.c:4473
do_symlinkat+0x1b2/0x3f0 fs/namei.c:4499
__do_sys_symlink fs/namei.c:4520 [inline]
__se_sys_symlink fs/namei.c:4518 [inline]
__x64_sys_symlink+0x7e/0x90 fs/namei.c:4518

4 locks held by syz.2.28/5999:
#0: ffff88807faca418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:403
#1: ffff88804ac82130 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88804ac82130 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3553 [inline]
#1: ffff88804ac82130 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3786
#2: ffff88804ac81e80 (&ni->ni_lock#3/6){+.+.}-{3:3}, at: ni_lock_dir fs/ntfs3/ntfs_fs.h:1125 [inline]
#2: ffff88804ac81e80 (&ni->ni_lock#3/6){+.+.}-{3:3}, at: ntfs_atomic_open+0x1ec/0x520 fs/ntfs3/namei.c:404
#3: ffff88807fac8270 (&wnd->rw_lock){++++}-{3:3}, at: run_unpack_ex+0x702/0xba0 fs/ntfs3/run.c:1098

stack backtrace:
CPU: 1 PID: 5999 Comm: syz.2.28 Not tainted 6.6.100-syzkaller #0

RIP: 0033:0x7f2ef178e9a9

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:00007f2ef25b1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2ef19b5fa0 RCX: 00007f2ef178e9a9
RDX: 0000000000143042 RSI: 00002000000000c0 RDI: ffffffffffffff9c
RBP: 00007f2ef1810d69 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000a0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2ef19b5fa0 R15: 00007ffe9d61b998
</TASK>


---
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