loop0: detected capacity change from 0 to 1024
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.1039/14041 is trying to acquire lock:
ffff888116fab908 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_get_block+0x39e/0x1530

but task is already holding lock:
ffff88802e08b8f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x94/0x9b0

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&sbi->alloc_mutex){+.+.}-{4:4}:
       lock_acquire+0x120/0x360
       __mutex_lock+0x187/0x1350
       hfsplus_block_allocate+0x94/0x9b0
       hfsplus_file_extend+0xae3/0x1990
       hfsplus_get_block+0x411/0x1530
       __block_write_begin_int+0x6b5/0x1900
       cont_write_begin+0x789/0xb50
       hfsplus_write_begin+0x66/0xb0
       generic_perform_write+0x2c5/0x900
       generic_file_write_iter+0x117/0x550
       iter_file_splice_write+0x975/0x10e0
       direct_splice_actor+0x101/0x160
       splice_direct_to_actor+0x5a8/0xcc0
       do_splice_direct+0x181/0x270
       do_sendfile+0x4da/0x7e0
       __se_sys_sendfile64+0x13e/0x190
       do_syscall_64+0xfa/0x3b0
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}:
       validate_chain+0xb9b/0x2140
       __lock_acquire+0xab9/0xd20
       lock_acquire+0x120/0x360
       __mutex_lock+0x187/0x1350
       hfsplus_get_block+0x39e/0x1530
       block_read_full_folio+0x29f/0x830
       filemap_read_folio+0x117/0x380
       do_read_cache_folio+0x350/0x590
       read_cache_page+0x5d/0x170
       hfsplus_block_allocate+0xe4/0x9b0
       hfsplus_file_extend+0xae3/0x1990
       hfsplus_get_block+0x411/0x1530
       __block_write_begin_int+0x6b5/0x1900
       cont_write_begin+0x789/0xb50
       hfsplus_write_begin+0x66/0xb0
       page_symlink+0x26f/0x430
       hfsplus_symlink+0xca/0x260
       vfs_symlink+0x143/0x2f0
       do_symlinkat+0x1b1/0x3f0
       __x64_sys_symlinkat+0x95/0xb0
       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(&sbi->alloc_mutex);
                               lock(&HFSPLUS_I(inode)->extents_lock);
                               lock(&sbi->alloc_mutex);
  lock(&HFSPLUS_I(inode)->extents_lock);

 *** DEADLOCK ***

5 locks held by syz.0.1039/14041:
 #0: ffff88802f43c428 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888116fac1f8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
 #2: ffff88802e08b998 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_symlink+0x81/0x260
 #3: ffff888116fad508 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990
 #4: ffff88802e08b8f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x94/0x9b0

stack backtrace:
CPU: 1 UID: 0 PID: 14041 Comm: syz.0.1039 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
 hfsplus_get_block+0x39e/0x1530
 block_read_full_folio+0x29f/0x830
 filemap_read_folio+0x117/0x380
 do_read_cache_folio+0x350/0x590
 read_cache_page+0x5d/0x170
 hfsplus_block_allocate+0xe4/0x9b0
 hfsplus_file_extend+0xae3/0x1990
 hfsplus_get_block+0x411/0x1530
 __block_write_begin_int+0x6b5/0x1900
 cont_write_begin+0x789/0xb50
 hfsplus_write_begin+0x66/0xb0
 page_symlink+0x26f/0x430
 hfsplus_symlink+0xca/0x260
 vfs_symlink+0x143/0x2f0
 do_symlinkat+0x1b1/0x3f0
 __x64_sys_symlinkat+0x95/0xb0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f565698ec29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f565776e038 EFLAGS: 00000246 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 00007f5656bd5fa0 RCX: 00007f565698ec29
RDX: 0000200000000200 RSI: ffffffffffffff9c RDI: 00002000000003c0
RBP: 00007f5656a11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5656bd6038 R14: 00007f5656bd5fa0 R15: 00007fff126f58b8
 </TASK>
