syzbot

loop0: detected capacity change from 0 to 4096
======================================================
WARNING: possible circular locking dependency detected
5.15.165-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor131/3614 is trying to acquire lock:
ffff888029776a28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117

but task is already holding lock:
ffff88806d2f2880 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:809 [inline]
ffff88806d2f2880 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: ntfs_file_write_iter+0x1ca/0x540 fs/ntfs3/file.c:1122

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       inode_lock include/linux/fs.h:789 [inline]
       ntfs_file_mmap+0x589/0x7e0 fs/ntfs3/file.c:401
       call_mmap include/linux/fs.h:2177 [inline]
       mmap_region+0x10e7/0x1670 mm/mmap.c:1791
       do_mmap+0x78d/0xe00 mm/mmap.c:1575
       vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:551
       ksys_mmap_pgoff+0x559/0x780 mm/mmap.c:1624
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 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+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
       mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117
       do_user_addr_fault arch/x86/mm/fault.c:1308 [inline]
       handle_page_fault arch/x86/mm/fault.c:1445 [inline]
       exc_page_fault+0x596/0x700 arch/x86/mm/fault.c:1501
       asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
       __get_user_nocheck_1+0x6/0x10 arch/x86/lib/getuser.S:103
       fault_in_readable+0x172/0x2e0 mm/gup.c:1801
       fault_in_iov_iter_readable+0x14a/0x1d0 lib/iov_iter.c:460
       generic_perform_write+0x1c9/0x5b0 mm/filemap.c:3775
       __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
       ntfs_file_write_iter+0x48b/0x540 fs/ntfs3/file.c:1143
       call_write_iter include/linux/fs.h:2172 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0xacd/0xe50 fs/read_write.c:594
       ksys_write+0x1a2/0x2c0 fs/read_write.c:647
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0xb0 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#17);
                               lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#17);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

3 locks held by syz-executor131/3614:
 #0: ffff88807838b9f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2cb/0x380 fs/file.c:1088
 #1: ffff88807d436460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590
 #2: ffff88806d2f2880 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: inode_trylock include/linux/fs.h:809 [inline]
 #2: ffff88806d2f2880 (&sb->s_type->i_mutex_key#17){+.+.}-{3:3}, at: ntfs_file_write_iter+0x1ca/0x540 fs/ntfs3/file.c:1122

stack backtrace:
CPU: 1 PID: 3614 Comm: syz-executor131 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 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+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498
 mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117
 do_user_addr_fault arch/x86/mm/fault.c:1308 [inline]
 handle_page_fault arch/x86/mm/fault.c:1445 [inline]
 exc_page_fault+0x596/0x700 arch/x86/mm/fault.c:1501
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0010:__get_user_nocheck_1+0x6/0x10 arch/x86/lib/getuser.S:124
Code: d0 73 64 48 19 d2 48 21 d0 0f 01 cb 48 8b 10 31 c0 0f 01 ca c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 0f 01 cb 0f ae e8 <0f> b6 10 31 c0 0f 01 ca c3 90 0f 01 cb 0f ae e8 0f b7 10 31 c0 0f
RSP: 0018:ffffc90002e57978 EFLAGS: 00050287
RAX: 00000000200f5000 RBX: 00000000200f4100 RCX: ffff88801debbb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002e57a38 R08: ffffffff81b73106 R09: fffff9400036c2d7
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000ffffffff
R13: 00000000200f5000 R14: 00000000200f6000 R15: 0000000000000000
 fault_in_readable+0x172/0x2e0 mm/gup.c:1801
 fault_in_iov_iter_readable+0x14a/0x1d0 lib/iov_iter.c:460
 generic_perform_write+0x1c9/0x5b0 mm/filemap.c:3775
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 ntfs_file_write_iter+0x48b/0x540 fs/ntfs3/file.c:1143
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacd/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f47ed3d29e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 1a 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:00007f47ed38e218 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f47ed47a6c8 RCX: 00007f47ed3d29e9
RDX: 000000000208e24b RSI: 0000000020000100 RDI: 0000000000000004
RBP: 00007f47ed47a6c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f47ed42704d
R13: 6e65646469686f6e R14: 00007f47ed427055 R15: 636f6c6c61657270
 </TASK>
----------------
Code disassembly (best guess):
   0:	d0 73 64             	shlb   0x64(%rbx)
   3:	48 19 d2             	sbb    %rdx,%rdx
   6:	48 21 d0             	and    %rdx,%rax
   9:	0f 01 cb             	stac
   c:	48 8b 10             	mov    (%rax),%rdx
   f:	31 c0                	xor    %eax,%eax
  11:	0f 01 ca             	clac
  14:	c3                   	ret
  15:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  1c:	00 00 00
  1f:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  24:	0f 01 cb             	stac
  27:	0f ae e8             	lfence
* 2a:	0f b6 10             	movzbl (%rax),%edx <-- trapping instruction
  2d:	31 c0                	xor    %eax,%eax
  2f:	0f 01 ca             	clac
  32:	c3                   	ret
  33:	90                   	nop
  34:	0f 01 cb             	stac
  37:	0f ae e8             	lfence
  3a:	0f b7 10             	movzwl (%rax),%edx
  3d:	31 c0                	xor    %eax,%eax
  3f:	0f                   	.byte 0xf