======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.9.5469/22008 is trying to acquire lock:
ffff8881b9661b10 (mapping.invalidate_lock#6){++++}-{4:4}, at: filemap_fault+0x938/0x12e0

but task is already holding lock:
ffff88816fcca8c0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x2f0

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&mm->mmap_lock){++++}-{4:4}:
       __might_fault+0xcb/0x130
       _copy_to_user+0x2c/0xb0
       fiemap_fill_next_extent+0x1dd/0x3c0
       ni_fiemap+0x8f1/0xca0
       ntfs_fiemap+0x11d/0x1a0
       do_vfs_ioctl+0x125a/0x1530
       __se_sys_ioctl+0x82/0x170
       do_syscall_64+0xe2/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&ni->ni_lock#2/5){+.+.}-{4:4}:
       __mutex_lock+0x19f/0x1340
       ntfs_fallocate+0x5a0/0x1130
       vfs_fallocate+0x669/0x7e0
       file_ioctl+0x63f/0x860
       do_vfs_ioctl+0xc26/0x1530
       __se_sys_ioctl+0x82/0x170
       do_syscall_64+0xe2/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (mapping.invalidate_lock#6){++++}-{4:4}:
       __lock_acquire+0x15a5/0x2cf0
       lock_acquire+0x106/0x330
       down_read+0x47/0x2e0
       filemap_fault+0x938/0x12e0
       __do_fault+0x138/0x390
       do_pte_missing+0x2208/0x3320
       handle_mm_fault+0x1b8c/0x32a0
       do_user_addr_fault+0x75b/0x1360
       exc_page_fault+0x6a/0xc0
       asm_exc_page_fault+0x26/0x30
       rep_movs_alternative+0x30/0x90
       _copy_from_user+0x7a/0xb0
       ___sys_sendmsg+0x1c6/0x360
       __x64_sys_sendmsg+0x1bd/0x2a0
       do_syscall_64+0xe2/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  mapping.invalidate_lock#6 --> &ni->ni_lock#2/5 --> &mm->mmap_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(&mm->mmap_lock);
                               lock(&ni->ni_lock#2/5);
                               lock(&mm->mmap_lock);
  rlock(mapping.invalidate_lock#6);

 *** DEADLOCK ***

1 lock held by syz.9.5469/22008:
 #0: ffff88816fcca8c0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x2f0

stack backtrace:
CPU: 0 UID: 0 PID: 22008 Comm: syz.9.5469 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_circular_bug+0x2e1/0x300
 check_noncircular+0x12e/0x150
 __lock_acquire+0x15a5/0x2cf0
 lock_acquire+0x106/0x330
 down_read+0x47/0x2e0
 filemap_fault+0x938/0x12e0
 __do_fault+0x138/0x390
 do_pte_missing+0x2208/0x3320
 handle_mm_fault+0x1b8c/0x32a0
 do_user_addr_fault+0x75b/0x1360
 exc_page_fault+0x6a/0xc0
 asm_exc_page_fault+0x26/0x30
RIP: 0010:rep_movs_alternative+0x30/0x90
Code: 83 f9 08 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 e9 3d 47 04 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08
RSP: 0018:ffffc90003e57af8 EFLAGS: 00010206
RAX: 00007ffffffff001 RBX: 0000000000000038 RCX: 0000000000000038
RDX: 0000000000000001 RSI: 0000200000000180 RDI: ffffc90003e57b80
RBP: ffffc90003e57d90 R08: ffffc90003e57bb7 R09: 1ffff920007caf76
R10: dffffc0000000000 R11: fffff520007caf77 R12: ffffc90003e57de0
R13: 1ffff920007caf6c R14: ffffc90003e57b80 R15: 0000200000000180
 _copy_from_user+0x7a/0xb0
 ___sys_sendmsg+0x1c6/0x360
 __x64_sys_sendmsg+0x1bd/0x2a0
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde4519acb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fde46039028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fde45416090 RCX: 00007fde4519acb9
RDX: 0000000000000000 RSI: 0000200000000180 RDI: 0000000000000004
RBP: 00007fde45208bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fde45416128 R14: 00007fde45416090 R15: 00007fff8d25d818
 </TASK>
