syzbot

loop0: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
5.15.112-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor126/3962 is trying to acquire lock:
ffff0000c84579d8 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0xa0/0x128 mm/memory.c:5310

but task is already holding lock:
ffff0000dc7df700 (&ni->ni_lock/4){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1108 [inline]
ffff0000dc7df700 (&ni->ni_lock/4){+.+.}-{3:3}, at: ntfs_fiemap+0xec/0x168 fs/ntfs3/file.c:1223

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ni->ni_lock/4){+.+.}-{3:3}:
       __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
       ni_lock fs/ntfs3/ntfs_fs.h:1108 [inline]
       attr_data_get_block+0x35c/0x1c18 fs/ntfs3/attrib.c:846
       ntfs_file_mmap+0x3a4/0x688 fs/ntfs3/file.c:389
       call_mmap include/linux/fs.h:2108 [inline]
       mmap_region+0xcb4/0x12f0 mm/mmap.c:1791
       do_mmap+0x6c0/0xcec mm/mmap.c:1575
       vm_mmap_pgoff+0x1a4/0x2b4 mm/util.c:551
       ksys_mmap_pgoff+0x458/0x668 mm/mmap.c:1624
       __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline]
       __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline]
       __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #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:3787 [inline]
       __lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011
       lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622
       __might_fault+0xc8/0x128 mm/memory.c:5311
       _copy_to_user include/linux/uaccess.h:174 [inline]
       copy_to_user include/linux/uaccess.h:200 [inline]
       fiemap_fill_next_extent+0x1b4/0x44c fs/ioctl.c:144
       ni_fiemap+0xc40/0xe10 fs/ntfs3/frecord.c:1894
       ntfs_fiemap+0x110/0x168 fs/ntfs3/file.c:1225
       ioctl_fiemap fs/ioctl.c:219 [inline]
       do_vfs_ioctl+0x1bcc/0x2a38 fs/ioctl.c:814
       __do_sys_ioctl fs/ioctl.c:872 [inline]
       __se_sys_ioctl fs/ioctl.c:860 [inline]
       __arm64_sys_ioctl+0xe4/0x1c8 fs/ioctl.c:860
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ni->ni_lock/4);
                               lock(&mm->mmap_lock);
                               lock(&ni->ni_lock/4);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz-executor126/3962:
 #0: ffff0000dc7df700 (&ni->ni_lock/4){+.+.}-{3:3}, at: ni_lock fs/ntfs3/ntfs_fs.h:1108 [inline]
 #0: ffff0000dc7df700 (&ni->ni_lock/4){+.+.}-{3:3}, at: ntfs_fiemap+0xec/0x168 fs/ntfs3/file.c:1223

stack backtrace:
CPU: 1 PID: 3962 Comm: syz-executor126 Not tainted 5.15.112-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011
 check_noncircular+0x2cc/0x378 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:3787 [inline]
 __lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011
 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622
 __might_fault+0xc8/0x128 mm/memory.c:5311
 _copy_to_user include/linux/uaccess.h:174 [inline]
 copy_to_user include/linux/uaccess.h:200 [inline]
 fiemap_fill_next_extent+0x1b4/0x44c fs/ioctl.c:144
 ni_fiemap+0xc40/0xe10 fs/ntfs3/frecord.c:1894
 ntfs_fiemap+0x110/0x168 fs/ntfs3/file.c:1225
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x1bcc/0x2a38 fs/ioctl.c:814
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0xe4/0x1c8 fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584