Message-ID: <6806769e.050a0220.297747.02f9.GAE@google.com>
Date: Mon, 21 Apr 2025 09:47:26 -0700
From: syzbot <syzbot+839ea12926e5df362ff1@...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 ni_set_compress

Hello,

syzbot found the following issue on:

HEAD commit:    cfb2e2c57aef Merge tag 'mm-hotfixes-stable-2025-04-16-19-5..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13441fe4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b8b55ae4a62d79b8
dashboard link: https://syzkaller.appspot.com/bug?extid=839ea12926e5df362ff1
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/5590e609f231/disk-cfb2e2c5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6865703da4ca/vmlinux-cfb2e2c5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6944af88a20f/bzImage-cfb2e2c5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+839ea12926e5df362ff1@...kaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
6.15.0-rc2-syzkaller-00087-gcfb2e2c57aef #0 Not tainted
------------------------------------------------------
syz.5.237/7937 is trying to acquire lock:
ffff88805e9fca70 (&ni->ni_lock#3/5){+.+.}-{4:4}, at: ni_lock fs/ntfs3/ntfs_fs.h:1105 [inline]
ffff88805e9fca70 (&ni->ni_lock#3/5){+.+.}-{4:4}, at: ni_set_compress+0x174/0x5a0 fs/ntfs3/frecord.c:3359

but task is already holding lock:
ffff88805e9fcea8 (mapping.invalidate_lock#12){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:912 [inline]
ffff88805e9fcea8 (mapping.invalidate_lock#12){++++}-{4:4}, at: ntfs_fileattr_set+0x2a9/0x4a0 fs/ntfs3/file.c:108

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (mapping.invalidate_lock#12){++++}-{4:4}:
       lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
       down_read+0xb3/0xa50 kernel/locking/rwsem.c:1524
       filemap_invalidate_lock_shared include/linux/fs.h:922 [inline]
       filemap_fault+0x66b/0x13d0 mm/filemap.c:3391
       __do_fault+0x135/0x390 mm/memory.c:5098
       do_read_fault mm/memory.c:5518 [inline]
       do_fault mm/memory.c:5652 [inline]
       do_pte_missing mm/memory.c:4160 [inline]
       handle_pte_fault+0x3f0c/0x61c0 mm/memory.c:5997
       __handle_mm_fault mm/memory.c:6140 [inline]
       handle_mm_fault+0x1030/0x1aa0 mm/memory.c:6309
       do_user_addr_fault arch/x86/mm/fault.c:1388 [inline]
       handle_page_fault arch/x86/mm/fault.c:1480 [inline]
       exc_page_fault+0x2bb/0x920 arch/x86/mm/fault.c:1538
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
       do_strncpy_from_user lib/strncpy_from_user.c:-1 [inline]
       strncpy_from_user+0xb8/0x280 lib/strncpy_from_user.c:130
       getname_flags+0xf1/0x530 fs/namei.c:157
       getname include/linux/fs.h:2852 [inline]
       do_sys_openat2+0xbf/0x1d0 fs/open.c:1423
       do_sys_open fs/open.c:1444 [inline]
       __do_sys_open fs/open.c:1452 [inline]
       __se_sys_open fs/open.c:1448 [inline]
       __x64_sys_open+0x226/0x280 fs/open.c:1448
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&mm->mmap_lock){++++}-{4:4}:
       lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
       __might_fault+0xc6/0x120 mm/memory.c:7151
       _inline_copy_to_user include/linux/uaccess.h:192 [inline]
       _copy_to_user+0x2c/0xb0 lib/usercopy.c:26
       copy_to_user include/linux/uaccess.h:225 [inline]
       fiemap_fill_next_extent+0x237/0x420 fs/ioctl.c:145
       ni_fiemap+0xa42/0x12a0 fs/ntfs3/frecord.c:2007
       ntfs_fiemap+0x134/0x180 fs/ntfs3/file.c:1380
       ioctl_fiemap fs/ioctl.c:220 [inline]
       do_vfs_ioctl+0x1975/0x2750 fs/ioctl.c:840
       __do_sys_ioctl fs/ioctl.c:904 [inline]
       __se_sys_ioctl+0x80/0x160 fs/ioctl.c:892
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ni->ni_lock#3/5){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3166 [inline]
       check_prevs_add kernel/locking/lockdep.c:3285 [inline]
       validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909
       __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235
       lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
       __mutex_lock_common kernel/locking/mutex.c:601 [inline]
       __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746
       ni_lock fs/ntfs3/ntfs_fs.h:1105 [inline]
       ni_set_compress+0x174/0x5a0 fs/ntfs3/frecord.c:3359
       ntfs_fileattr_set+0x2ef/0x4a0 fs/ntfs3/file.c:114
       vfs_fileattr_set+0x901/0xd50 fs/ioctl.c:696
       ioctl_setflags fs/ioctl.c:728 [inline]
       do_vfs_ioctl+0x180c/0x2750 fs/ioctl.c:869
       __do_sys_ioctl fs/ioctl.c:904 [inline]
       __se_sys_ioctl+0x80/0x160 fs/ioctl.c:892
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ni->ni_lock#3/5 --> &mm->mmap_lock --> mapping.invalidate_lock#12

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(mapping.invalidate_lock#12);
                               lock(&mm->mmap_lock);
                               lock(mapping.invalidate_lock#12);
  lock(&ni->ni_lock#3/5);

 *** DEADLOCK ***

3 locks held by syz.5.237/7937:
 #0: ffff88807cdac420 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write_file+0x5e/0x200 fs/namespace.c:600
 #1: ffff88805e9fcd08 (&sb->s_type->i_mutex_key#31){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #1: ffff88805e9fcd08 (&sb->s_type->i_mutex_key#31){+.+.}-{4:4}, at: vfs_fileattr_set+0x13b/0xd50 fs/ioctl.c:681
 #2: ffff88805e9fcea8 (mapping.invalidate_lock#12){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:912 [inline]
 #2: ffff88805e9fcea8 (mapping.invalidate_lock#12){++++}-{4:4}, at: ntfs_fileattr_set+0x2a9/0x4a0 fs/ntfs3/file.c:108

stack backtrace:
CPU: 0 UID: 0 PID: 7937 Comm: syz.5.237 Not tainted 6.15.0-rc2-syzkaller-00087-gcfb2e2c57aef #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2079
 check_noncircular+0x142/0x160 kernel/locking/lockdep.c:2211
 check_prev_add kernel/locking/lockdep.c:3166 [inline]
 check_prevs_add kernel/locking/lockdep.c:3285 [inline]
 validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909
 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235
 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
 __mutex_lock_common kernel/locking/mutex.c:601 [inline]
 __mutex_lock+0x1a5/0x10c0 kernel/locking/mutex.c:746
 ni_lock fs/ntfs3/ntfs_fs.h:1105 [inline]
 ni_set_compress+0x174/0x5a0 fs/ntfs3/frecord.c:3359
 ntfs_fileattr_set+0x2ef/0x4a0 fs/ntfs3/file.c:114
 vfs_fileattr_set+0x901/0xd50 fs/ioctl.c:696
 ioctl_setflags fs/ioctl.c:728 [inline]
 do_vfs_ioctl+0x180c/0x2750 fs/ioctl.c:869
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x80/0x160 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5dca38e169
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:00007f5dcb1ed038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5dca5b5fa0 RCX: 00007f5dca38e169
RDX: 00002000000006c0 RSI: 0000000040086602 RDI: 0000000000000004
RBP: 00007f5dca410a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5dca5b5fa0 R15: 00007ffcd4490398
 </TASK>


---
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