Message-ID: <0000000000002488fc061ae886f8@google.com>
Date: Sat, 15 Jun 2024 00:17:25 -0700
From: syzbot <syzbot+c1751b6739d83d70bb75@...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_file_mmap

Hello,

syzbot found the following issue on:

HEAD commit:    a957267fa7e9 Add linux-next specific files for 20240611
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1139caa2980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9a880e96898e79f8
dashboard link: https://syzkaller.appspot.com/bug?extid=c1751b6739d83d70bb75
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/6451759a606b/disk-a957267f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7f635dbe5b8a/vmlinux-a957267f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/33eafd1b8aec/bzImage-a957267f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c1751b6739d83d70bb75@...kaller.appspotmail.com

loop0: detected capacity change from 0 to 4096
ntfs3: loop0: Different NTFS sector size (4096) and media sector size (512).
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc3-next-20240611-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.0/9000 is trying to acquire lock:
ffff88805b15dbb8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:795 [inline]
ffff88805b15dbb8 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_file_mmap+0x5d8/0x860 fs/ntfs3/file.c:302

but task is already holding lock:
ffff88807d087398 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline]
ffff88807d087398 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x17c/0x3d0 mm/util.c:571

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&mm->mmap_lock){++++}-{3:3}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5817
       gup_fast_fallback+0x24c/0x2b40 mm/gup.c:3534
       pin_user_pages_fast+0xcc/0x160 mm/gup.c:3658
       iov_iter_extract_user_pages lib/iov_iter.c:1583 [inline]
       iov_iter_extract_pages+0x3db/0x720 lib/iov_iter.c:1646
       dio_refill_pages fs/direct-io.c:173 [inline]
       dio_get_page fs/direct-io.c:214 [inline]
       do_direct_IO fs/direct-io.c:916 [inline]
       __blockdev_direct_IO+0x150f/0x49d0 fs/direct-io.c:1249
       blockdev_direct_IO include/linux/fs.h:3201 [inline]
       ntfs_direct_IO+0x195/0x370 fs/ntfs3/inode.c:803
       generic_file_direct_write+0x130/0x350 mm/filemap.c:3941
       __generic_file_write_iter+0x129/0x230 mm/filemap.c:4097
       ntfs_file_write_iter+0x68f/0x770 fs/ntfs3/file.c:1126
       new_sync_write fs/read_write.c:497 [inline]
       vfs_write+0xa72/0xc90 fs/read_write.c:590
       ksys_write+0x1a0/0x2c0 fs/read_write.c:643
       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 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3159 [inline]
       check_prevs_add kernel/locking/lockdep.c:3278 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3902
       __lock_acquire+0x1359/0x2000 kernel/locking/lockdep.c:5194
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5817
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1579
       inode_lock include/linux/fs.h:795 [inline]
       ntfs_file_mmap+0x5d8/0x860 fs/ntfs3/file.c:302
       call_mmap include/linux/fs.h:2123 [inline]
       mmap_region+0xe8f/0x2090 mm/mmap.c:2927
       do_mmap+0x8ad/0xfa0 mm/mmap.c:1438
       vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:573
       ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1484
       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:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#21);
                               lock(&mm->mmap_lock);
  lock(&sb->s_type->i_mutex_key#21);

 *** DEADLOCK ***

1 lock held by syz-executor.0/9000:
 #0: ffff88807d087398 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline]
 #0: ffff88807d087398 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x17c/0x3d0 mm/util.c:571

stack backtrace:
CPU: 0 PID: 9000 Comm: syz-executor.0 Not tainted 6.10.0-rc3-next-20240611-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:91 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:117
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2075
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2204
 check_prev_add kernel/locking/lockdep.c:3159 [inline]
 check_prevs_add kernel/locking/lockdep.c:3278 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3902
 __lock_acquire+0x1359/0x2000 kernel/locking/lockdep.c:5194
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5817
 down_write+0x3a/0x50 kernel/locking/rwsem.c:1579
 inode_lock include/linux/fs.h:795 [inline]
 ntfs_file_mmap+0x5d8/0x860 fs/ntfs3/file.c:302
 call_mmap include/linux/fs.h:2123 [inline]
 mmap_region+0xe8f/0x2090 mm/mmap.c:2927
 do_mmap+0x8ad/0xfa0 mm/mmap.c:1438
 vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:573
 ksys_mmap_pgoff+0x4f1/0x720 mm/mmap.c:1484
 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: 0033:0x7f7e2707cea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7e27de60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f7e271b3f80 RCX: 00007f7e2707cea9
RDX: 00000000007fffff RSI: 0000000000003000 RDI: 0000000020000000
RBP: 00007f7e270ebff4 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000012 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7e271b3f80 R15: 00007ffee8137f98
 </TASK>


---
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