loop5: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.5.2693/19821 is trying to acquire lock: ffff888024899478 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1540 fs/hfs/extent.c:397 but task is already holding lock: ffff88802939e0b0 (&tree->tree_lock#2/1){+.+.}-{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#2/1){+.+.}-{4:4}: lock_acquire+0x117/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:770 hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2f6/0x1540 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1c5/0x770 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:4409 [inline] open_last_lookups fs/namei.c:4509 [inline] path_openat+0x190f/0x3d90 fs/namei.c:4753 do_filp_open+0x1fa/0x410 fs/namei.c:4783 do_sys_openat2+0x121/0x1c0 fs/open.c:1432 do_sys_open fs/open.c:1447 [inline] __do_sys_openat fs/open.c:1463 [inline] __se_sys_openat fs/open.c:1458 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1458 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 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+0xb9b/0x2130 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:770 hfs_extend_file+0xda/0x1540 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+0x161/0x1e0 fs/hfs/extent.c:144 hfs_write_inode+0xc6/0x8a0 fs/hfs/inode.c:440 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x7e1/0x12f0 fs/fs-writeback.c:1802 writeback_single_inode+0x493/0xc70 fs/fs-writeback.c:1858 write_inode_now+0x160/0x1d0 fs/fs-writeback.c:2924 hfs_file_fsync+0xa4/0x140 fs/hfs/inode.c:687 generic_write_sync include/linux/fs.h:2616 [inline] generic_file_write_iter+0x319/0x550 mm/filemap.c:4461 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 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#2/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); lock(&HFS_I(tree->inode)->extents_lock); *** DEADLOCK *** 4 locks held by syz.5.2693/19821: #0: ffff888075a7d5f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1255 #1: ffff88802939a420 (sb_writers#32){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline] #1: ffff88802939a420 (sb_writers#32){.+.+}-{0:0}, at: vfs_write+0x211/0xb30 fs/read_write.c:682 #2: ffff888024899ca0 (&sb->s_type->i_mutex_key#52){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #2: ffff888024899ca0 (&sb->s_type->i_mutex_key#52){+.+.}-{4:4}, at: hfs_file_fsync+0x9a/0x140 fs/hfs/inode.c:684 #3: ffff88802939e0b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x18e/0x300 fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 UID: 0 PID: 19821 Comm: syz.5.2693 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043 check_noncircular+0x134/0x160 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+0xb9b/0x2130 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:770 hfs_extend_file+0xda/0x1540 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+0x161/0x1e0 fs/hfs/extent.c:144 hfs_write_inode+0xc6/0x8a0 fs/hfs/inode.c:440 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x7e1/0x12f0 fs/fs-writeback.c:1802 writeback_single_inode+0x493/0xc70 fs/fs-writeback.c:1858 write_inode_now+0x160/0x1d0 fs/fs-writeback.c:2924 hfs_file_fsync+0xa4/0x140 fs/hfs/inode.c:687 generic_write_sync include/linux/fs.h:2616 [inline] generic_file_write_iter+0x319/0x550 mm/filemap.c:4461 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f825578f749 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:00007f8256630038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f82559e5fa0 RCX: 00007f825578f749 RDX: 0000000000001006 RSI: 0000200000000940 RDI: 0000000000000004 RBP: 00007f8255813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f82559e6038 R14: 00007f82559e5fa0 R15: 00007ffcacc3a638