======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
kworker/u4:6/4353 is trying to acquire lock:
ffff88807dc268f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x13f0 fs/hfs/extent.c:397
but task is already holding lock:
ffff88807417a0b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 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#2/1){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747
hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1
hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
hfs_get_block+0x553/0xc50 fs/hfs/extent.c:366
block_read_full_folio+0x3e6/0xf00 fs/buffer.c:2271
filemap_read_folio+0x16b/0x770 mm/filemap.c:2490
do_read_cache_folio+0x2a0/0x760 mm/filemap.c:3659
do_read_cache_page+0x32/0x220 mm/filemap.c:3701
read_mapping_page include/linux/pagemap.h:793 [inline]
__hfs_bnode_create+0x4ad/0x7b0 fs/hfs/bnode.c:388
hfs_bnode_find+0x21e/0xd40 fs/hfs/bnode.c:433
hfs_brec_find+0x178/0x500 fs/hfs/bfind.c:132
hfs_brec_read+0x20/0x100 fs/hfs/bfind.c:171
hfs_cat_find_brec+0x174/0x3f0 fs/hfs/catalog.c:194
hfs_fill_super+0xff8/0x15b0 fs/hfs/super.c:419
mount_bdev+0x287/0x3c0 fs/super.c:1443
legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
vfs_get_tree+0x88/0x270 fs/super.c:1573
do_new_mount+0x24a/0xa40 fs/namespace.c:3078
do_mount fs/namespace.c:3421 [inline]
__do_sys_mount fs/namespace.c:3629 [inline]
__se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #0 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain kernel/locking/lockdep.c:3825 [inline]
__lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747
hfs_extend_file+0xfb/0x13f0 fs/hfs/extent.c:397
hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:234
__hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
hfs_ext_write_extent+0x17b/0x200 fs/hfs/extent.c:144
hfs_write_inode+0xd8/0xa20 fs/hfs/inode.c:434
write_inode fs/fs-writeback.c:1470 [inline]
__writeback_single_inode+0x75b/0x1160 fs/fs-writeback.c:1687
writeback_sb_inodes+0xb30/0x1850 fs/fs-writeback.c:1913
wb_writeback+0x482/0xd50 fs/fs-writeback.c:2087
wb_do_writeback fs/fs-writeback.c:2230 [inline]
wb_workfn+0x423/0xee0 fs/fs-writeback.c:2270
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&tree->tree_lock#2/1);
lock(&HFS_I(tree->inode)->extents_lock);
lock(&tree->tree_lock#2/1);
lock(&HFS_I(tree->inode)->extents_lock);
*** DEADLOCK ***
3 locks held by kworker/u4:6/4353:
#0: ffff888019291138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc90004617d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#2: ffff88807417a0b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1
stack backtrace:
CPU: 0 PID: 4353 Comm: kworker/u4:6 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: writeback wb_workfn (flush-7:1)
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain kernel/locking/lockdep.c:3825 [inline]
__lock_acquire+0x2d07/0x7d10 kernel/locking/lockdep.c:5049
lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x12d/0xaf0 kernel/locking/mutex.c:747
hfs_extend_file+0xfb/0x13f0 fs/hfs/extent.c:397
hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:234
__hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121
hfs_ext_write_extent+0x17b/0x200 fs/hfs/extent.c:144
hfs_write_inode+0xd8/0xa20 fs/hfs/inode.c:434
write_inode fs/fs-writeback.c:1470 [inline]
__writeback_single_inode+0x75b/0x1160 fs/fs-writeback.c:1687
writeback_sb_inodes+0xb30/0x1850 fs/fs-writeback.c:1913
wb_writeback+0x482/0xd50 fs/fs-writeback.c:2087
wb_do_writeback fs/fs-writeback.c:2230 [inline]
wb_workfn+0x423/0xee0 fs/fs-writeback.c:2270
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
hfs: new node 0 already hashed?
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4353 at fs/hfs/bnode.c:520 hfs_bnode_create+0x37a/0x400 fs/hfs/bnode.c:519
Modules linked in:
CPU: 1 PID: 4353 Comm: kworker/u4:6 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: writeback wb_workfn (flush-7:1)
RIP: 0010:hfs_bnode_create+0x37a/0x400 fs/hfs/bnode.c:520
Code: aa a2 8a 89 ee e8 56 3b d6 07 e9 ab fd ff ff e8 4c 51 37 ff 48 89 df e8 04 8b eb 07 48 c7 c7 00 ab a2 8a 89 ee e8 36 3b d6 07 <0f> 0b eb b7 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c b7 fc ff ff 4c
RSP: 0018:ffffc90004616e80 EFLAGS: 00010246
RAX: 000000000000001f RBX: ffff88807417a0e0 RCX: fe38b7c7e323bb00
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffc90004616b87 R09: 1ffff920008c2d70
R10: dffffc0000000000 R11: fffff520008c2d71 R12: 0000000000000000
R13: ffff88807417a000 R14: ffff888075612f00 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa2f6d840c0 CR3: 00000000773be000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
hfs_bmap_alloc+0x53d/0x5d0 fs/hfs/btree.c:291
hfs_btree_inc_height+0xfd/0xac0 fs/hfs/brec.c:490
hfs_brec_insert+0x744/0xbd0 fs/hfs/brec.c:148
__hfs_ext_write_extent+0x2a1/0x470 fs/hfs/extent.c:124
hfs_ext_write_extent+0x17b/0x200 fs/hfs/extent.c:144
hfs_write_inode+0xd8/0xa20 fs/hfs/inode.c:434
write_inode fs/fs-writeback.c:1470 [inline]
__writeback_single_inode+0x75b/0x1160 fs/fs-writeback.c:1687
writeback_sb_inodes+0xb30/0x1850 fs/fs-writeback.c:1913
wb_writeback+0x482/0xd50 fs/fs-writeback.c:2087
wb_do_writeback fs/fs-writeback.c:2230 [inline]
wb_workfn+0x423/0xee0 fs/fs-writeback.c:2270
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295