====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.7.4190/21211 is trying to acquire lock: ffff888028a6c0b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 but task is already holding lock: ffff888027d45578 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_extend_file+0xda/0x1230 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+0x91/0x7d0 fs/hfs/inode.c:429 write_inode fs/fs-writeback.c:1525 [inline] __writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745 writeback_single_inode+0x1f3/0x6a0 fs/fs-writeback.c:1801 write_inode_now+0x160/0x1d0 fs/fs-writeback.c:2864 hfs_file_fsync+0xa4/0x140 fs/hfs/inode.c:676 generic_write_sync include/linux/fs.h:3042 [inline] generic_file_write_iter+0x319/0x550 mm/filemap.c:4322 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/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&tree->tree_lock#2/1){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2ee/0x1230 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3708 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x14f4/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 file_open_name fs/open.c:1379 [inline] filp_open+0x176/0x1d0 fs/open.c:1399 coredump_file+0x33e/0xaf0 fs/coredump.c:931 vfs_coredump+0x1688/0x2a50 fs/coredump.c:1141 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:40 [inline] exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:73 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(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock#2/1); *** DEADLOCK *** 4 locks held by syz.7.4190/21211: #0: ffff888049f3c428 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff888027d47120 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #1: ffff888027d47120 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: open_last_lookups fs/namei.c:3804 [inline] #1: ffff888027d47120 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4043 #2: ffff888028a680b0 (&tree->tree_lock#2){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 #3: ffff888027d45578 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 stack backtrace: CPU: 1 UID: 0 PID: 21211 Comm: syz.7.4190 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:760 hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x2ee/0x1230 fs/hfs/extent.c:401 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x1b3/0x640 fs/hfs/catalog.c:104 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3708 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x14f4/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 file_open_name fs/open.c:1379 [inline] filp_open+0x176/0x1d0 fs/open.c:1399 coredump_file+0x33e/0xaf0 fs/coredump.c:931 vfs_coredump+0x1688/0x2a50 fs/coredump.c:1141 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:40 [inline] exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:73 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: 0033:0x7f6dc858ebf1 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 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:fffffffffffffea0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f6dc87b6090 RCX: 00007f6dc858ebe9 RDX: 0000000000000000 RSI: fffffffffffffea0 RDI: 0000000000000000 RBP: 00007f6dc8611e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6dc87b6128 R14: 00007f6dc87b6090 R15: 00007ffe41050b08