Message-ID: <000000000000d1011406202be206@google.com>
Date: Tue, 20 Aug 2024 23:45:21 -0700
From: syzbot <syzbot+12f3574df80036f0f9ca@...kaller.appspotmail.com>
To: almaz.alexandrovich@...agon-software.com, linux-kernel@...r.kernel.org, 
	ntfs3@...ts.linux.dev, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [ntfs3?] possible deadlock in ntfs_unlink

Hello,

syzbot found the following issue on:

HEAD commit:    85652baa895b Merge tag 'block-6.11-20240824' of git://git...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=104377c9980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=92c0312151c4e32e
dashboard link: https://syzkaller.appspot.com/bug?extid=12f3574df80036f0f9ca
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f48bb8a1e215/disk-85652baa.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a4eced38e143/vmlinux-85652baa.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3d21ddc8de52/bzImage-85652baa.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+12f3574df80036f0f9ca@...kaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.11.0-rc3-syzkaller-00271-g85652baa895b #0 Not tainted
------------------------------------------------------
syz-executor/5964 is trying to acquire lock:
ffff88805d371708 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ni_lock_dir fs/ntfs3/ntfs_fs.h:1115 [inline]
ffff88805d371708 (&ni->ni_lock#2/5){+.+.}-{3:3}, at: ntfs_unlink+0xb1/0xf0 fs/ntfs3/namei.c:177

but task is already holding lock:
ffff88805d371248 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
ffff88805d371248 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: vfs_unlink+0xe4/0x650 fs/namei.c:4411

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       down_write+0x99/0x220 kernel/locking/rwsem.c:1579
       inode_lock include/linux/fs.h:799 [inline]
       ntfs_file_mmap+0x5bf/0x850 fs/ntfs3/file.c:368
       call_mmap include/linux/fs.h:2129 [inline]
       mmap_region+0xe8f/0x2090 mm/mmap.c:2957
       do_mmap+0x8f9/0x1010 mm/mmap.c:1468
       vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588
       ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1514
       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

-> #2 (&mm->mmap_lock){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __might_fault+0xc6/0x120 mm/memory.c:6388
       _inline_copy_to_user include/linux/uaccess.h:176 [inline]
       _copy_to_user+0x2a/0xb0 lib/usercopy.c:26
       copy_to_user include/linux/uaccess.h:209 [inline]
       ni_fiemap+0x5b4/0x1910 fs/ntfs3/frecord.c:2140
       ntfs_fiemap+0x132/0x180 fs/ntfs3/file.c:1279
       ioctl_fiemap fs/ioctl.c:220 [inline]
       do_vfs_ioctl+0x1c07/0x2e50 fs/ioctl.c:841
       __do_sys_ioctl fs/ioctl.c:905 [inline]
       __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
       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

-> #1 (&ni->ni_lock/4){+.+.}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       ni_lock fs/ntfs3/ntfs_fs.h:1110 [inline]
       ntfs_save_wsl_perm+0x8f/0x500 fs/ntfs3/xattr.c:959
       ntfs_create_inode+0x2314/0x3880 fs/ntfs3/inode.c:1667
       ntfs_create+0x3d/0x50 fs/ntfs3/namei.c:110
       lookup_open fs/namei.c:3578 [inline]
       open_last_lookups fs/namei.c:3647 [inline]
       path_openat+0x1a9a/0x3470 fs/namei.c:3883
       do_filp_open+0x235/0x490 fs/namei.c:3913
       do_sys_openat2+0x13e/0x1d0 fs/open.c:1416
       do_sys_open fs/open.c:1431 [inline]
       __do_sys_openat fs/open.c:1447 [inline]
       __se_sys_openat fs/open.c:1442 [inline]
       __x64_sys_openat+0x247/0x2a0 fs/open.c:1442
       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

-> #0 (&ni->ni_lock#2/5){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
       __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
       ni_lock_dir fs/ntfs3/ntfs_fs.h:1115 [inline]
       ntfs_unlink+0xb1/0xf0 fs/ntfs3/namei.c:177
       vfs_unlink+0x365/0x650 fs/namei.c:4422
       do_unlinkat+0x4ae/0x830 fs/namei.c:4486
       __do_sys_unlink fs/namei.c:4534 [inline]
       __se_sys_unlink fs/namei.c:4532 [inline]
       __x64_sys_unlink+0x47/0x50 fs/namei.c:4532
       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

other info that might help us debug this:

Chain exists of:
  &ni->ni_lock#2/5 --> &mm->mmap_lock --> &sb->s_type->i_mutex_key#29

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#29);
                               lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#29);
  lock(&ni->ni_lock#2/5);

 *** DEADLOCK ***

3 locks held by syz-executor/5964:
 #0: ffff88807f642420
 (sb_writers
#12){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
 #1: ffff88805d3719a0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:834 [inline]
 #1: ffff88805d3719a0 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: do_unlinkat+0x26a/0x830 fs/namei.c:4473
 #2: ffff88805d371248 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #2: ffff88805d371248 (&sb->s_type->i_mutex_key#29){+.+.}-{3:3}, at: vfs_unlink+0xe4/0x650 fs/namei.c:4411

stack backtrace:
CPU: 0 UID: 0 PID: 5964 Comm: syz-executor Not tainted 6.11.0-rc3-syzkaller-00271-g85652baa895b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868
 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752
 ni_lock_dir fs/ntfs3/ntfs_fs.h:1115 [inline]
 ntfs_unlink+0xb1/0xf0 fs/ntfs3/namei.c:177
 vfs_unlink+0x365/0x650 fs/namei.c:4422
 do_unlinkat+0x4ae/0x830 fs/namei.c:4486
 __do_sys_unlink fs/namei.c:4534 [inline]
 __se_sys_unlink fs/namei.c:4532 [inline]
 __x64_sys_unlink+0x47/0x50 fs/namei.c:4532
 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: 0033:0x7f30a4779427
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 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:00007ffc62b6cfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f30a4779427
RDX: 00007ffc62b6d000 RSI: 00007ffc62b6d090 RDI: 00007ffc62b6d090
RBP: 00007ffc62b6d090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffc62b6e180
R13: 00007f30a47e77b4 R14: 000000000002694c R15: 00007ffc62b6f240
 </TASK>


---
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