loop3: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.3.28142/5159 is trying to acquire lock: ffff88805ac52c68 (&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: ffff88807dedc0b0 (&tree->tree_lock/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/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_get_block+0x4fc/0xbe0 fs/hfs/extent.c:366 block_read_full_folio+0x47b/0xff0 fs/buffer.c:2406 filemap_read_folio+0x16b/0x790 mm/filemap.c:2420 do_read_cache_folio+0x485/0x7f0 mm/filemap.c:3800 do_read_cache_page+0x32/0x260 mm/filemap.c:3866 read_mapping_page include/linux/pagemap.h:892 [inline] __hfs_bnode_create+0x4ae/0x7c0 fs/hfs/bnode.c:390 hfs_bnode_find+0x21f/0xce0 fs/hfs/bnode.c:435 hfs_brec_find+0x17c/0x500 fs/hfs/bfind.c:135 hfs_brec_read+0x24/0x110 fs/hfs/bfind.c:174 hfs_cat_find_brec+0x173/0x3f0 fs/hfs/catalog.c:194 hfs_fill_super+0xe38/0x13b0 fs/hfs/super.c:419 mount_bdev+0x21c/0x2c0 fs/super.c:1654 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1775 do_new_mount+0x24a/0xa60 fs/namespace.c:3412 do_mount fs/namespace.c:3780 [inline] __do_sys_mount fs/namespace.c:3989 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3966 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:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3281 [inline] validate_chain kernel/locking/lockdep.c:3897 [inline] __lock_acquire+0x3a07/0x7eb0 kernel/locking/lockdep.c:5171 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5790 __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 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4027 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4148 call_write_iter include/linux/fs.h:2019 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_write+0x151/0x260 fs/read_write.c:637 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/1); lock(&HFS_I(tree->inode)->extents_lock); lock(&tree->tree_lock/1); lock(&HFS_I(tree->inode)->extents_lock); *** DEADLOCK *** 5 locks held by syz.3.28142/5159: #0: ffff888032322fc8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888055f3e418 (sb_writers#34){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffff88805ac540e8 (&sb->s_type->i_mutex_key#45){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #2: ffff88805ac540e8 (&sb->s_type->i_mutex_key#45){+.+.}-{3:3}, at: generic_file_write_iter+0x83/0x2e0 mm/filemap.c:4145 #3: ffff88805ac53f28 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xeb/0x1320 fs/hfs/extent.c:397 #4: ffff88807dedc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x170/0x1e0 fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 PID: 5159 Comm: syz.3.28142 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2215 check_prev_add kernel/locking/lockdep.c:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3281 [inline] validate_chain kernel/locking/lockdep.c:3897 [inline] __lock_acquire+0x3a07/0x7eb0 kernel/locking/lockdep.c:5171 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5790 __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 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4027 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4148 call_write_iter include/linux/fs.h:2019 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_write+0x151/0x260 fs/read_write.c:637 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: 0033:0x7fe346d9f559 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:00007fe347cd0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe347025fa0 RCX: 00007fe346d9f559 RDX: 000000000208e24b RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007fe346e36b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe347026038 R14: 00007fe347025fa0 R15: 00007ffd9b0dae38