syzbot

EXT4-fs (loop0): encrypted files will use data=ordered instead of data journaling mode
EXT4-fs (loop0): 1 truncate cleaned up
======================================================
WARNING: possible circular locking dependency detected
6.1.137-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor319/4344 is trying to acquire lock:
ffff888073a0b628 (&sb->s_type->i_mutex_key#8/1){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff888073a0b628 (&sb->s_type->i_mutex_key#8/1){+.+.}-{3:3}, at: ext4_xattr_inode_create fs/ext4/xattr.c:1474 [inline]
ffff888073a0b628 (&sb->s_type->i_mutex_key#8/1){+.+.}-{3:3}, at: ext4_xattr_inode_lookup_create+0x18b5/0x1d10 fs/ext4/xattr.c:1556

but task is already holding lock:
ffff888073a0e6d8 (&ei->i_data_sem/3){++++}-{3:3}, at: ext4_setattr+0x13d4/0x19f0 fs/ext4/inode.c:5593

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ei->i_data_sem/3){++++}-{3:3}:
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       ext4_update_i_disksize fs/ext4/ext4.h:3378 [inline]
       ext4_xattr_inode_write fs/ext4/xattr.c:1412 [inline]
       ext4_xattr_inode_lookup_create+0x15c4/0x1d10 fs/ext4/xattr.c:1562
       ext4_xattr_ibody_set+0x1fe/0x690 fs/ext4/xattr.c:2224
       ext4_xattr_set_handle+0xa7c/0x12b0 fs/ext4/xattr.c:2401
       ext4_xattr_set+0x22a/0x320 fs/ext4/xattr.c:2515
       __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
       __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
       vfs_setxattr+0x168/0x2f0 fs/xattr.c:309
       do_setxattr fs/xattr.c:594 [inline]
       setxattr+0x2b2/0x2d0 fs/xattr.c:617
       path_setxattr+0x142/0x280 fs/xattr.c:636
       __do_sys_lsetxattr fs/xattr.c:659 [inline]
       __se_sys_lsetxattr fs/xattr.c:655 [inline]
       __x64_sys_lsetxattr+0xb4/0xd0 fs/xattr.c:655
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&sb->s_type->i_mutex_key#8/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
       lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ext4_xattr_inode_create fs/ext4/xattr.c:1474 [inline]
       ext4_xattr_inode_lookup_create+0x18b5/0x1d10 fs/ext4/xattr.c:1556
       ext4_xattr_block_set+0x23a/0x32a0 fs/ext4/xattr.c:1876
       ext4_xattr_move_to_block fs/ext4/xattr.c:2625 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2700 [inline]
       ext4_expand_extra_isize_ea+0x109b/0x19b0 fs/ext4/xattr.c:2792
       __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5965
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:6008 [inline]
       __ext4_mark_inode_dirty+0x47f/0x770 fs/ext4/inode.c:6086
       ext4_setattr+0x1457/0x19f0 fs/ext4/inode.c:5596
       notify_change+0xc74/0xf40 fs/attr.c:499
       do_truncate+0x197/0x220 fs/open.c:65
       vfs_truncate+0x262/0x2f0 fs/open.c:111
       do_sys_truncate+0xdc/0x190 fs/open.c:134
       do_syscall_x64 arch/x86/entry/common.c:51 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_data_sem/3);
                               lock(&sb->s_type->i_mutex_key#8/1);
                               lock(&ei->i_data_sem/3);
  lock(&sb->s_type->i_mutex_key#8/1);

 *** DEADLOCK ***

5 locks held by syz-executor319/4344:
 #0: ffff8880773f0460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:393
 #1: ffff888073a0e850 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888073a0e850 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: do_truncate+0x183/0x220 fs/open.c:63
 #2: ffff888073a0e9f0 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:803 [inline]
 #2: ffff888073a0e9f0 (mapping.invalidate_lock){++++}-{3:3}, at: ext4_setattr+0xe6f/0x19f0 fs/ext4/inode.c:5553
 #3: ffff888073a0e6d8 (&ei->i_data_sem/3){++++}-{3:3}, at: ext4_setattr+0x13d4/0x19f0 fs/ext4/inode.c:5593
 #4: ffff888073a0e518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:162 [inline]
 #4: ffff888073a0e518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6005 [inline]
 #4: ffff888073a0e518 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x3fe/0x770 fs/ext4/inode.c:6086

stack backtrace:
CPU: 0 PID: 4344 Comm: syz-executor319 Not tainted 6.1.137-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:758 [inline]
 ext4_xattr_inode_create fs/ext4/xattr.c:1474 [inline]
 ext4_xattr_inode_lookup_create+0x18b5/0x1d10 fs/ext4/xattr.c:1556
 ext4_xattr_block_set+0x23a/0x32a0 fs/ext4/xattr.c:1876
 ext4_xattr_move_to_block fs/ext4/xattr.c:2625 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2700 [inline]
 ext4_expand_extra_isize_ea+0x109b/0x19b0 fs/ext4/xattr.c:2792
 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5965
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6008 [inline]
 __ext4_mark_inode_dirty+0x47f/0x770 fs/ext4/inode.c:6086
 ext4_setattr+0x1457/0x19f0 fs/ext4/inode.c:5596
 notify_change+0xc74/0xf40 fs/attr.c:499
 do_truncate+0x197/0x220 fs/open.c:65
 vfs_truncate+0x262/0x2f0 fs/open.c:111
 do_sys_truncate+0xdc/0x190 fs/open.c:134
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2c24c172e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe643b9cf8 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00002000000000c0 RCX: 00007f2c24c172e9
RDX: 00007f2c24c172e9 RSI: 0000000000008008 RDI: 00002000000000c0
RBP: 0031656c69662f2e R08: 00007ffe643b9d30 R09: 00007ffe643b9d30
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe643b9d1c
R13: 000000000000002f R14: 431bde82d7b634db R15: 00007ffe643b9d50
 </TASK>