loop0: detected capacity change from 0 to 1024
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.0/5345 is trying to acquire lock:
ffff8880522e4108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1f8/0x1ba0 fs/hfsplus/extents.c:453

but task is already holding lock:
ffff88803ef880b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x290 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}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
       hfsplus_find_init+0x168/0x290 fs/hfsplus/bfind.c:28
       hfsplus_file_truncate+0x374/0xbd0 fs/hfsplus/extents.c:579
       hfsplus_setattr+0x1c4/0x270 fs/hfsplus/inode.c:286
       notify_change+0xc1a/0xf40 fs/attr.c:546
       do_truncate+0x1a4/0x220 fs/open.c:68
       do_ftruncate+0x4a5/0x560 fs/open.c:195
       do_sys_ftruncate fs/open.c:207 [inline]
       __do_sys_ftruncate fs/open.c:212 [inline]
       __se_sys_ftruncate fs/open.c:210 [inline]
       __x64_sys_ftruncate+0x92/0xf0 fs/open.c:210
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0xf80 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:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
       lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
       hfsplus_file_extend+0x1f8/0x1ba0 fs/hfsplus/extents.c:453
       hfsplus_bmap_reserve+0x125/0x510 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+0x437/0x1ba0 fs/hfsplus/extents.c:457
       hfsplus_get_block+0x40a/0x15d0 fs/hfsplus/extents.c:245
       __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
       block_write_begin fs/buffer.c:2256 [inline]
       cont_write_begin+0x789/0xb50 fs/buffer.c:2594
       hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:48
       generic_perform_write+0x2c5/0x900 mm/filemap.c:4300
       generic_file_write_iter+0x117/0x550 mm/filemap.c:4443
       iter_file_splice_write+0x972/0x10b0 fs/splice.c:738
       do_splice_from fs/splice.c:938 [inline]
       direct_splice_actor+0x101/0x160 fs/splice.c:1161
       splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105
       do_splice_direct_actor fs/splice.c:1204 [inline]
       do_splice_direct+0x181/0x270 fs/splice.c:1230
       vfs_copy_file_range+0xb03/0x1370 fs/read_write.c:1632
       __do_sys_copy_file_range fs/read_write.c:1681 [inline]
       __se_sys_copy_file_range+0x2fb/0x470 fs/read_write.c:1648
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

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.0.0/5345:
 #0: ffff8880002b4420 (sb_writers#12){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160
 #1: ffff8880522e7238 (&sb->s_type->i_mutex_key#22){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #1: ffff8880522e7238 (&sb->s_type->i_mutex_key#22){+.+.}-{4:4}, at: generic_file_write_iter+0xeb/0x550 mm/filemap.c:4440
 #2: ffff8880522e7048 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1f8/0x1ba0 fs/hfsplus/extents.c:453
 #3: ffff88803ef880b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x290 fs/hfsplus/bfind.c:28

stack backtrace:
CPU: 0 UID: 0 PID: 5345 Comm: syz.0.0 Not tainted syzkaller #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+0x2e2/0x300 kernel/locking/lockdep.c:2043
 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
 __mutex_lock_common kernel/locking/mutex.c:614 [inline]
 __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
 hfsplus_file_extend+0x1f8/0x1ba0 fs/hfsplus/extents.c:453
 hfsplus_bmap_reserve+0x125/0x510 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+0x437/0x1ba0 fs/hfsplus/extents.c:457
 hfsplus_get_block+0x40a/0x15d0 fs/hfsplus/extents.c:245
 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145
 block_write_begin fs/buffer.c:2256 [inline]
 cont_write_begin+0x789/0xb50 fs/buffer.c:2594
 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:48
 generic_perform_write+0x2c5/0x900 mm/filemap.c:4300
 generic_file_write_iter+0x117/0x550 mm/filemap.c:4443
 iter_file_splice_write+0x972/0x10b0 fs/splice.c:738
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x101/0x160 fs/splice.c:1161
 splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x181/0x270 fs/splice.c:1230
 vfs_copy_file_range+0xb03/0x1370 fs/read_write.c:1632
 __do_sys_copy_file_range fs/read_write.c:1681 [inline]
 __se_sys_copy_file_range+0x2fb/0x470 fs/read_write.c:1648
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4def98f7c9
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:00007f4df0857038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146
RAX: ffffffffffffffda RBX: 00007f4defbe5fa0 RCX: 00007f4def98f7c9
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f4defa13f91 R08: fffffbffa003e45b R09: 0700000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4defbe6038 R14: 00007f4defbe5fa0 R15: 00007ffca266b178
 </TASK>