======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 Not tainted
------------------------------------------------------
syz.0.16/5517 is trying to acquire lock:
ffff888059564108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458

but task is already holding lock:
ffff8880441060b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&tree->tree_lock/1){+.+.}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:602 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
       hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28
       hfsplus_file_truncate+0x383/0xb40 fs/hfsplus/extents.c:583
       hfsplus_delete_inode+0x180/0x230 fs/hfsplus/inode.c:-1
       hfsplus_unlink+0x4e3/0x730 fs/hfsplus/dir.c:405
       vfs_unlink+0x391/0x650 fs/namei.c:4595
       do_unlinkat+0x350/0x560 fs/namei.c:4659
       __do_sys_unlink fs/namei.c:4705 [inline]
       __se_sys_unlink fs/namei.c:4703 [inline]
       __x64_sys_unlink+0x47/0x50 fs/namei.c:4703
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3168 [inline]
       check_prevs_add kernel/locking/lockdep.c:3287 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
       __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:602 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
       hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458
       hfsplus_bmap_reserve+0x122/0x500 fs/hfsplus/btree.c:358
       __hfsplus_ext_write_extent+0x28d/0x5b0 fs/hfsplus/extents.c:104
       __hfsplus_ext_cache_extent+0x89/0xe30 fs/hfsplus/extents.c:186
       hfsplus_ext_read_extent fs/hfsplus/extents.c:218 [inline]
       hfsplus_file_extend+0x444/0x1990 fs/hfsplus/extents.c:462
       hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245
       __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2151
       block_write_begin fs/buffer.c:2262 [inline]
       cont_write_begin+0x789/0xb50 fs/buffer.c:2601
       hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46
       generic_perform_write+0x2c7/0x910 mm/filemap.c:4112
       generic_file_write_iter+0x10f/0x540 mm/filemap.c:4255
       __kernel_write_iter+0x390/0x860 fs/read_write.c:619
       dump_emit_page fs/coredump.c:1112 [inline]
       dump_user_range+0x873/0xc70 fs/coredump.c:1186
       elf_core_dump+0x32ed/0x3900 fs/binfmt_elf.c:2075
       do_coredump+0x2806/0x3440 fs/coredump.c:950
       get_signal+0x1109/0x1340 kernel/signal.c:3019
       arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
       irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:184
       exc_page_fault+0x9f/0xf0 arch/x86/mm/fault.c:1535
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

other info that might help us debug this:

 Possible unsafe locking scenario:

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

 *** DEADLOCK ***

4 locks held by syz.0.16/5517:
 #0: ffff888031b64428 (sb_writers#12){.+.+}-{0:0}, at: do_coredump+0x27cb/0x3440 fs/coredump.c:949
 #1: ffff888059566b78 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
 #1: ffff888059566b78 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: generic_file_write_iter+0xe3/0x540 mm/filemap.c:4252
 #2: ffff888059566988 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458
 #3: ffff8880441060b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x15a/0x1d0 fs/hfsplus/bfind.c:28

stack backtrace:
CPU: 0 UID: 0 PID: 5517 Comm: syz.0.16 Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3168 [inline]
 check_prevs_add kernel/locking/lockdep.c:3287 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 __mutex_lock_common kernel/locking/mutex.c:602 [inline]
 __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
 hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458
 hfsplus_bmap_reserve+0x122/0x500 fs/hfsplus/btree.c:358
 __hfsplus_ext_write_extent+0x28d/0x5b0 fs/hfsplus/extents.c:104
 __hfsplus_ext_cache_extent+0x89/0xe30 fs/hfsplus/extents.c:186
 hfsplus_ext_read_extent fs/hfsplus/extents.c:218 [inline]
 hfsplus_file_extend+0x444/0x1990 fs/hfsplus/extents.c:462
 hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2151
 block_write_begin fs/buffer.c:2262 [inline]
 cont_write_begin+0x789/0xb50 fs/buffer.c:2601
 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46
 generic_perform_write+0x2c7/0x910 mm/filemap.c:4112
 generic_file_write_iter+0x10f/0x540 mm/filemap.c:4255
 __kernel_write_iter+0x390/0x860 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1112 [inline]
 dump_user_range+0x873/0xc70 fs/coredump.c:1186
 elf_core_dump+0x32ed/0x3900 fs/binfmt_elf.c:2075
 do_coredump+0x2806/0x3440 fs/coredump.c:950
 get_signal+0x1109/0x1340 kernel/signal.c:3019
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:184
 exc_page_fault+0x9f/0xf0 arch/x86/mm/fault.c:1535
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f9d9238e931
Code: 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:00000000fffffe10 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f9d925b5fa0 RCX: 00007f9d9238e929
RDX: 0000000000000000 RSI: 00000000fffffe10 RDI: 0000000000000000
RBP: 00007f9d92410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9d925b5fa0 R14: 00007f9d925b5fa0 R15: 0000000000000006
 </TASK>