syzbot

loop2: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
5.15.189-syzkaller #0 Not tainted
------------------------------------------------------
syz.2.1506/19105 is trying to acquire lock:
ffff88802c0e9628 (&mm->mmap_lock){++++}-{3:3}, at: get_current arch/x86/include/asm/current.h:15 [inline]
ffff88802c0e9628 (&mm->mmap_lock){++++}-{3:3}, at: internal_get_user_pages_fast+0x1af/0x2080 mm/gup.c:2895

but task is already holding lock:
ffff88805fc0afe0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:807 [inline]
ffff88805fc0afe0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_file_write_iter+0x1d1/0x590 fs/ntfs3/file.c:1123

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:787 [inline]
       ntfs_file_mmap+0x516/0x720 fs/ntfs3/file.c:401
       call_mmap include/linux/fs.h:2177 [inline]
       mmap_file+0x5d/0xb0 mm/util.c:1092
       __mmap_region mm/mmap.c:1792 [inline]
       mmap_region+0xd0d/0x15e0 mm/mmap.c:2929
       do_mmap+0x77a/0xdf0 mm/mmap.c:1582
       vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:551
       ksys_mmap_pgoff+0x542/0x780 mm/mmap.c:1631
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
       lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
       internal_get_user_pages_fast+0x1fa/0x2080 mm/gup.c:2895
       iov_iter_get_pages+0x225/0x5b0 lib/iov_iter.c:1544
       dio_refill_pages fs/direct-io.c:173 [inline]
       dio_get_page fs/direct-io.c:217 [inline]
       do_direct_IO fs/direct-io.c:938 [inline]
       do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
       __blockdev_direct_IO+0x1060/0x3c90 fs/direct-io.c:1368
       blockdev_direct_IO include/linux/fs.h:3344 [inline]
       ntfs_direct_IO+0x194/0x390 fs/ntfs3/inode.c:798
       generic_file_direct_write+0x22c/0x490 mm/filemap.c:3687
       __generic_file_write_iter+0x2b1/0x4e0 mm/filemap.c:3869
       ntfs_file_write_iter+0x4d5/0x590 fs/ntfs3/file.c:1144
       do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1
       do_iter_write+0x205/0x7b0 fs/read_write.c:855
       vfs_writev fs/read_write.c:928 [inline]
       do_pwritev+0x204/0x340 fs/read_write.c:1025
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

2 locks held by syz.2.1506/19105:
 #0: ffff888075b46460 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev fs/read_write.c:927 [inline]
 #0: ffff888075b46460 (sb_writers#13){.+.+}-{0:0}, at: do_pwritev+0x1f2/0x340 fs/read_write.c:1025
 #1: ffff88805fc0afe0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:807 [inline]
 #1: ffff88805fc0afe0 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: ntfs_file_write_iter+0x1d1/0x590 fs/ntfs3/file.c:1123

stack backtrace:
CPU: 0 PID: 19105 Comm: syz.2.1506 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 internal_get_user_pages_fast+0x1fa/0x2080 mm/gup.c:2895
 iov_iter_get_pages+0x225/0x5b0 lib/iov_iter.c:1544
 dio_refill_pages fs/direct-io.c:173 [inline]
 dio_get_page fs/direct-io.c:217 [inline]
 do_direct_IO fs/direct-io.c:938 [inline]
 do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
 __blockdev_direct_IO+0x1060/0x3c90 fs/direct-io.c:1368
 blockdev_direct_IO include/linux/fs.h:3344 [inline]
 ntfs_direct_IO+0x194/0x390 fs/ntfs3/inode.c:798
 generic_file_direct_write+0x22c/0x490 mm/filemap.c:3687
 __generic_file_write_iter+0x2b1/0x4e0 mm/filemap.c:3869
 ntfs_file_write_iter+0x4d5/0x590 fs/ntfs3/file.c:1144
 do_iter_readv_writev+0x497/0x600 fs/read_write.c:-1
 do_iter_write+0x205/0x7b0 fs/read_write.c:855
 vfs_writev fs/read_write.c:928 [inline]
 do_pwritev+0x204/0x340 fs/read_write.c:1025
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f7b24100be9
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:00007f7b22368038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f7b24327fa0 RCX: 00007f7b24100be9
RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000005
RBP: 00007f7b24183e19 R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000002000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b24328038 R14: 00007f7b24327fa0 R15: 00007fff142f2b08
 </TASK>