====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.4.2070/13998 is trying to acquire lock: ffff888059d8e8f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xeb/0x1320 fs/hfs/extent.c:397 but task is already holding lock: ffff88807b0000b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x170/0x1e0 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+0x135/0xc80 kernel/locking/mutex.c:747 hfs_find_init+0x170/0x1e0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x342/0x1320 fs/hfs/extent.c:401 hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:269 hfs_cat_create+0x203/0x6a0 fs/hfs/catalog.c:104 hfs_create+0x66/0xd0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3496 [inline] open_last_lookups fs/namei.c:3564 [inline] path_openat+0x1705/0x3270 fs/namei.c:3798 do_filp_open+0x1f2/0x430 fs/namei.c:3828 do_sys_openat2+0x134/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_creat fs/open.c:1515 [inline] __se_sys_creat fs/open.c:1509 [inline] __x64_sys_creat+0x90/0xb0 fs/open.c:1509 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 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:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x135/0xc80 kernel/locking/mutex.c:747 hfs_extend_file+0xeb/0x1320 fs/hfs/extent.c:397 hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fc/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6e/0x9a0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x381/0x1320 fs/hfs/extent.c:401 hfs_get_block+0x402/0xbe0 fs/hfs/extent.c:353 __block_write_begin_int+0x571/0x1b00 fs/buffer.c:2124 __block_write_begin fs/buffer.c:2173 [inline] block_write_begin+0x9a/0x1e0 fs/buffer.c:2234 cont_write_begin+0x5fd/0x800 fs/buffer.c:2591 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:59 cont_expand_zero fs/buffer.c:2518 [inline] cont_write_begin+0x2c9/0x800 fs/buffer.c:2581 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:59 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4036 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4157 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x198/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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.4.2070/13998: #0: ffff88805d27c418 (sb_writers#21){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #1: ffff888059d8d738 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff888059d8d738 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: generic_file_write_iter+0x83/0x2e0 mm/filemap.c:4154 #2: ffff888059d8d578 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xeb/0x1320 fs/hfs/extent.c:397 #3: ffff88807b0000b0 (&tree->tree_lock#2/1){+.+.}-{3:3}, at: hfs_find_init+0x170/0x1e0 fs/hfs/bfind.c:-1 stack backtrace: CPU: 1 PID: 13998 Comm: syz.4.2070 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x135/0xc80 kernel/locking/mutex.c:747 hfs_extend_file+0xeb/0x1320 fs/hfs/extent.c:397 hfs_bmap_reserve+0x108/0x430 fs/hfs/btree.c:269 __hfs_ext_write_extent+0x1fc/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6e/0x9a0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x381/0x1320 fs/hfs/extent.c:401 hfs_get_block+0x402/0xbe0 fs/hfs/extent.c:353 __block_write_begin_int+0x571/0x1b00 fs/buffer.c:2124 __block_write_begin fs/buffer.c:2173 [inline] block_write_begin+0x9a/0x1e0 fs/buffer.c:2234 cont_write_begin+0x5fd/0x800 fs/buffer.c:2591 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:59 cont_expand_zero fs/buffer.c:2518 [inline] cont_write_begin+0x2c9/0x800 fs/buffer.c:2581 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:59 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4036 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4157 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x198/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3a8279e019 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3a83739028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f3a82a25fa0 RCX: 00007f3a8279e019 RDX: 0000000000000001 RSI: 0000200000000140 RDI: 0000000000000005 RBP: 00007f3a8283500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008000c61 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3a82a26038 R14: 00007f3a82a25fa0 R15: 00007ffdf0d95bf8