syzbot

EXT4-fs: Warning: mounting with an experimental mount option 'dioread_nolock' for blocksize < PAGE_SIZE
EXT4-fs (loop0): 1 truncate cleaned up
EXT4-fs (loop0): mounted filesystem without journal. Quota mode: writeback.
======================================================
WARNING: possible circular locking dependency detected
6.1.27-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor294/3541 is trying to acquire lock:
ffff888073145440 (&ea_inode->i_rwsem#8/1){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
ffff888073145440 (&ea_inode->i_rwsem#8/1){+.+.}-{3:3}, at: ext4_xattr_inode_iget+0x4a3/0x5e0 fs/ext4/xattr.c:438

but task is already holding lock:
ffff8880731448c0 (&ei->i_data_sem){++++}-{3:3}, at: ext4_setattr+0x13fa/0x1a00 fs/ext4/inode.c:5518

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ei->i_data_sem){++++}-{3:3}:
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       ext4_update_i_disksize fs/ext4/ext4.h:3383 [inline]
       ext4_xattr_inode_write fs/ext4/xattr.c:1413 [inline]
       ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1562 [inline]
       ext4_xattr_set_entry+0x3187/0x3c00 fs/ext4/xattr.c:1686
       ext4_xattr_ibody_set+0x11d/0x330 fs/ext4/xattr.c:2238
       ext4_xattr_set_handle+0xc72/0x1560 fs/ext4/xattr.c:2395
       ext4_xattr_set+0x231/0x3d0 fs/ext4/xattr.c:2509
       __vfs_setxattr+0x3e7/0x420 fs/xattr.c:182
       __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
       vfs_setxattr+0x21d/0x420 fs/xattr.c:309
       do_setxattr fs/xattr.c:594 [inline]
       setxattr+0x250/0x2b0 fs/xattr.c:617
       path_setxattr+0x1bc/0x2a0 fs/xattr.c:636
       __do_sys_setxattr fs/xattr.c:652 [inline]
       __se_sys_setxattr fs/xattr.c:648 [inline]
       __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&ea_inode->i_rwsem#8/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3098 [inline]
       check_prevs_add kernel/locking/lockdep.c:3217 [inline]
       validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3832
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
       lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:756 [inline]
       ext4_xattr_inode_iget+0x4a3/0x5e0 fs/ext4/xattr.c:438
       ext4_xattr_inode_get+0x17d/0x9a0 fs/ext4/xattr.c:501
       ext4_xattr_move_to_block fs/ext4/xattr.c:2590 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2692 [inline]
       ext4_expand_extra_isize_ea+0xe77/0x1bc0 fs/ext4/xattr.c:2784
       __ext4_expand_extra_isize+0x2f7/0x3d0 fs/ext4/inode.c:5890
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:5933 [inline]
       __ext4_mark_inode_dirty+0x54f/0x920 fs/ext4/inode.c:6011
       ext4_setattr+0x1493/0x1a00 fs/ext4/inode.c:5521
       notify_change+0xdcd/0x1080 fs/attr.c:482
       do_truncate+0x21c/0x300 fs/open.c:65
       handle_truncate fs/namei.c:3216 [inline]
       do_open fs/namei.c:3561 [inline]
       path_openat+0x27e2/0x2e60 fs/namei.c:3714
       do_filp_open+0x230/0x480 fs/namei.c:3741
       do_sys_openat2+0x13b/0x500 fs/open.c:1310
       do_sys_open fs/open.c:1326 [inline]
       __do_sys_creat fs/open.c:1402 [inline]
       __se_sys_creat fs/open.c:1396 [inline]
       __x64_sys_creat+0x11f/0x160 fs/open.c:1396
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->i_data_sem);
                               lock(&ea_inode->i_rwsem#8/1);
                               lock(&ei->i_data_sem);
  lock(&ea_inode->i_rwsem#8/1);

 *** DEADLOCK ***

5 locks held by syz-executor294/3541:
 #0: ffff88807b46a460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff888073144a38 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
 #1: ffff888073144a38 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: do_truncate+0x208/0x300 fs/open.c:63
 #2: ffff888073144bd8 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:801 [inline]
 #2: ffff888073144bd8 (mapping.invalidate_lock){++++}-{3:3}, at: ext4_setattr+0xec7/0x1a00 fs/ext4/inode.c:5478
 #3: ffff8880731448c0 (&ei->i_data_sem){++++}-{3:3}, at: ext4_setattr+0x13fa/0x1a00 fs/ext4/inode.c:5518
 #4: ffff888073144700 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:162 [inline]
 #4: ffff888073144700 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:5930 [inline]
 #4: ffff888073144700 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x4b0/0x920 fs/ext4/inode.c:6011

stack backtrace:
CPU: 1 PID: 3541 Comm: syz-executor294 Not tainted 6.1.27-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2fa/0x3b0 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3098 [inline]
 check_prevs_add kernel/locking/lockdep.c:3217 [inline]
 validate_chain+0x1667/0x58e0 kernel/locking/lockdep.c:3832
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:756 [inline]
 ext4_xattr_inode_iget+0x4a3/0x5e0 fs/ext4/xattr.c:438
 ext4_xattr_inode_get+0x17d/0x9a0 fs/ext4/xattr.c:501
 ext4_xattr_move_to_block fs/ext4/xattr.c:2590 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2692 [inline]
 ext4_expand_extra_isize_ea+0xe77/0x1bc0 fs/ext4/xattr.c:2784
 __ext4_expand_extra_isize+0x2f7/0x3d0 fs/ext4/inode.c:5890
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5933 [inline]
 __ext4_mark_inode_dirty+0x54f/0x920 fs/ext4/inode.c:6011
 ext4_setattr+0x1493/0x1a00 fs/ext4/inode.c:5521
 notify_change+0xdcd/0x1080 fs/attr.c:482
 do_truncate+0x21c/0x300 fs/open.c:65
 handle_truncate fs/namei.c:3216 [inline]
 do_open fs/namei.c:3561 [inline]
 path_openat+0x27e2/0x2e60 fs/namei.c:3714
 do_filp_open+0x230/0x480 fs/namei.c:3741
 do_sys_openat2+0x13b/0x500 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_creat fs/open.c:1402 [inline]
 __se_sys_creat fs/open.c:1396 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1396
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f7d36a45c59
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe3bff7dc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007f7d36a45c59
RDX: 00007f7d36a45c59 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 00007f7d36a05260 R08: 0000000000000000 R09: 0000000000000000