loop7: detected capacity change from 0 to 64
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.7.545/9608 is trying to acquire lock:
ffff888111d2c0b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200

but task is already holding lock:
ffff88811fbc80f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_get_block+0x268/0xbd0

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}:
       lock_acquire+0x120/0x360
       __mutex_lock+0x187/0x1350
       hfs_extend_file+0xda/0x1230
       hfs_bmap_reserve+0x107/0x430
       __hfs_ext_write_extent+0x1fa/0x470
       hfs_ext_write_extent+0x161/0x1e0
       hfs_write_inode+0x91/0x7d0
       __writeback_single_inode+0x6f1/0xff0
       writeback_sb_inodes+0x6c7/0x1010
       wb_writeback+0x43b/0xaf0
       wb_workfn+0x409/0xef0
       process_scheduled_works+0xae1/0x17b0
       worker_thread+0x8a0/0xda0
       kthread+0x711/0x8a0
       ret_from_fork+0x439/0x7d0
       ret_from_fork_asm+0x1a/0x30

-> #0 (&tree->tree_lock/1){+.+.}-{4:4}:
       validate_chain+0xb9b/0x2140
       __lock_acquire+0xab9/0xd20
       lock_acquire+0x120/0x360
       __mutex_lock+0x187/0x1350
       hfs_find_init+0x184/0x200
       hfs_get_block+0x51b/0xbd0
       block_read_full_folio+0x29f/0x830
       filemap_read_folio+0x117/0x380
       do_read_cache_folio+0x350/0x590
       read_cache_page+0x5d/0x170
       __hfs_bnode_create+0x4a8/0x7f0
       hfs_bnode_find+0x224/0xd00
       hfs_brec_find+0x159/0x500
       hfs_brec_read+0x24/0x110
       hfs_cat_find_brec+0x15c/0x3f0
       hfs_fill_super+0x426/0x620
       get_tree_bdev_flags+0x40e/0x4d0
       vfs_get_tree+0x92/0x2b0
       do_new_mount+0x2a2/0x9e0
       __se_sys_mount+0x317/0x410
       do_syscall_64+0xfa/0x3b0
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&HFS_I(tree->inode)->extents_lock);
                               lock(&tree->tree_lock/1);
                               lock(&HFS_I(tree->inode)->extents_lock);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

3 locks held by syz.7.545/9608:
 #0: ffff888029f9e0e0 (&type->s_umount_key#54/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970
 #1: ffff8881222700b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200
 #2: ffff88811fbc80f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_get_block+0x268/0xbd0

stack backtrace:
CPU: 1 UID: 0 PID: 9608 Comm: syz.7.545 Not tainted syzkaller #0 PREEMPT(full) 
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+0x189/0x250
 print_circular_bug+0x2ee/0x310
 check_noncircular+0x134/0x160
 validate_chain+0xb9b/0x2140
 __lock_acquire+0xab9/0xd20
 lock_acquire+0x120/0x360
 __mutex_lock+0x187/0x1350
 hfs_find_init+0x184/0x200
 hfs_get_block+0x51b/0xbd0
 block_read_full_folio+0x29f/0x830
 filemap_read_folio+0x117/0x380
 do_read_cache_folio+0x350/0x590
 read_cache_page+0x5d/0x170
 __hfs_bnode_create+0x4a8/0x7f0
 hfs_bnode_find+0x224/0xd00
 hfs_brec_find+0x159/0x500
 hfs_brec_read+0x24/0x110
 hfs_cat_find_brec+0x15c/0x3f0
 hfs_fill_super+0x426/0x620
 get_tree_bdev_flags+0x40e/0x4d0
 vfs_get_tree+0x92/0x2b0
 do_new_mount+0x2a2/0x9e0
 __se_sys_mount+0x317/0x410
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe8e57903ca
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe8e65d3e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fe8e65d3ef0 RCX: 00007fe8e57903ca
RDX: 0000200000000180 RSI: 0000200000000000 RDI: 00007fe8e65d3eb0
RBP: 0000200000000180 R08: 00007fe8e65d3ef0 R09: 0000000001000012
R10: 0000000001000012 R11: 0000000000000246 R12: 0000200000000000
R13: 00007fe8e65d3eb0 R14: 0000000000000314 R15: 00002000000003c0
 </TASK>
hfs: get root inode failed
loop7: detected capacity change from 0 to 512
EXT4-fs (loop7): encrypted files will use data=ordered instead of data journaling mode
EXT4-fs (loop7): 1 truncate cleaned up
EXT4-fs (loop7): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
EXT4-fs (loop7): unmounting filesystem 00000000-0000-0000-0000-000000000000.
