======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/u8:2/35 is trying to acquire lock:
ffff88807c06cbf0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xf2/0x15e0 fs/hfs/extent.c:397
but task is already holding lock:
ffff8880575040a8 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
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:632 [inline]
__mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794
hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_get_block+0x556/0xc50 fs/hfs/extent.c:366
block_read_full_folio+0x29f/0x830 fs/buffer.c:2417
filemap_read_folio+0x137/0x3b0 mm/filemap.c:2502
do_read_cache_folio+0x358/0x590 mm/filemap.c:4107
do_read_cache_page mm/filemap.c:4173 [inline]
read_cache_page+0x5d/0x170 mm/filemap.c:4182
read_mapping_page include/linux/pagemap.h:1011 [inline]
__hfs_bnode_create+0x4b9/0x980 fs/hfs/bnode.c:388
hfs_bnode_find+0x211/0xd40 fs/hfs/bnode.c:433
hfs_brec_find+0x17b/0x510 fs/hfs/bfind.c:135
hfs_brec_read+0x24/0x110 fs/hfs/bfind.c:174
hfs_cat_find_brec+0x177/0x3f0 fs/hfs/catalog.c:194
hfs_fill_super+0x4ff/0x750 fs/hfs/super.c:357
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3764 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3840
do_mount fs/namespace.c:4173 [inline]
__do_sys_mount fs/namespace.c:4372 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4349
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #0 (&HFS_I(tree->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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__mutex_lock_common kernel/locking/mutex.c:632 [inline]
__mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794
hfs_extend_file+0xf2/0x15e0 fs/hfs/extent.c:397
hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
__hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
hfs_ext_write_extent+0x17e/0x210 fs/hfs/extent.c:144
hfs_write_inode+0x117/0x960 fs/hfs/inode.c:459
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75a/0x10e0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x979/0x19d0 fs/fs-writeback.c:2054
wb_writeback+0x445/0xb00 fs/fs-writeback.c:2239
wb_do_writeback fs/fs-writeback.c:2386 [inline]
wb_workfn+0x3f8/0xf10 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3278 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3361
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3442
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&tree->tree_lock/1);
lock(&HFS_I(tree->inode)->extents_lock);
lock(&tree->tree_lock/1);
lock(&HFS_I(tree->inode)->extents_lock);
*** DEADLOCK ***
3 locks held by kworker/u8:2/35:
#0: ffff88801be84140 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3253 [inline]
#0: ffff88801be84140 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3361
#1: ffffc90000ab7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3254 [inline]
#1: ffffc90000ab7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3361
#2: ffff8880575040a8 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1
stack backtrace:
CPU: 0 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: writeback wb_workfn (flush-7:6)
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_circular_bug+0x2e1/0x300 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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__mutex_lock_common kernel/locking/mutex.c:632 [inline]
__mutex_lock+0x19e/0x1420 kernel/locking/mutex.c:794
hfs_extend_file+0xf2/0x15e0 fs/hfs/extent.c:397
hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269
__hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
hfs_ext_write_extent+0x17e/0x210 fs/hfs/extent.c:144
hfs_write_inode+0x117/0x960 fs/hfs/inode.c:459
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75a/0x10e0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x979/0x19d0 fs/fs-writeback.c:2054
wb_writeback+0x445/0xb00 fs/fs-writeback.c:2239
wb_do_writeback fs/fs-writeback.c:2386 [inline]
wb_workfn+0x3f8/0xf10 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3278 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3361
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3442
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
hfs: new node 0 already hashed?
------------[ cut here ]------------
1
WARNING: fs/hfs/bnode.c:520 at hfs_bnode_create+0x461/0x4f0 fs/hfs/bnode.c:520, CPU#1: kworker/u8:2/35
Modules linked in:
CPU: 1 UID: 0 PID: 35 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: writeback wb_workfn (flush-7:6)
RIP: 0010:hfs_bnode_create+0x461/0x4f0 fs/hfs/bnode.c:520
Code: e8 8b 89 ee e8 70 97 79 fe e9 cf fc ff ff e8 36 15 18 ff 4c 89 ef e8 4e ac 05 09 48 c7 c7 00 0f e8 8b 89 ee e8 50 97 79 fe 90 <0f> 0b 90 eb b0 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c d6 fb ff ff
RSP: 0018:ffffc90000ab6c60 EFLAGS: 00010246
RAX: 000000000000001f RBX: ffff888057504000 RCX: ad59ab8e2300cd00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffc90000ab69e7 R09: 1ffff92000156d3c
R10: dffffc0000000000 R11: fffff52000156d3d R12: 0000000000000000
R13: ffff8880575040d8 R14: ffff888035c41100 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125548000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7d3ceb2286 CR3: 000000007e52e000 CR4: 00000000003526f0
Call Trace:
hfs_bmap_alloc+0x5c1/0x650 fs/hfs/btree.c:326
hfs_btree_inc_height+0x100/0xad0 fs/hfs/brec.c:490
hfs_brec_insert+0x7ef/0xc90 fs/hfs/brec.c:148
__hfs_ext_write_extent+0x2a1/0x470 fs/hfs/extent.c:124
hfs_ext_write_extent+0x17e/0x210 fs/hfs/extent.c:144
hfs_write_inode+0x117/0x960 fs/hfs/inode.c:459
write_inode fs/fs-writeback.c:1582 [inline]
__writeback_single_inode+0x75a/0x10e0 fs/fs-writeback.c:1825
writeback_sb_inodes+0x979/0x19d0 fs/fs-writeback.c:2054
wb_writeback+0x445/0xb00 fs/fs-writeback.c:2239
wb_do_writeback fs/fs-writeback.c:2386 [inline]
wb_workfn+0x3f8/0xf10 fs/fs-writeback.c:2426
process_one_work kernel/workqueue.c:3278 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3361
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3442
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245