loop6: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.6.2106/15105 is trying to acquire lock: ffff8880249da7f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 but task is already holding lock: ffff8880574620b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 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+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_get_block+0x51b/0xbd0 fs/hfs/extent.c:366 block_read_full_folio+0x29f/0x830 fs/buffer.c:2420 filemap_read_folio+0x117/0x380 mm/filemap.c:2426 do_read_cache_folio+0x350/0x590 mm/filemap.c:3991 do_read_cache_page mm/filemap.c:4057 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:4066 read_mapping_page include/linux/pagemap.h:993 [inline] __hfs_bnode_create+0x4a8/0x7f0 fs/hfs/bnode.c:388 hfs_bnode_find+0x224/0xd00 fs/hfs/bnode.c:433 hfs_brec_find+0x159/0x500 fs/hfs/bfind.c:129 hfs_brec_read+0x24/0x110 fs/hfs/bfind.c:168 hfs_cat_find_brec+0x15c/0x3f0 fs/hfs/catalog.c:194 hfs_fill_super+0x426/0x620 fs/hfs/super.c:350 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 vfs_get_tree+0x92/0x2b0 fs/super.c:1751 fc_mount fs/namespace.c:1274 [inline] do_new_mount_fc fs/namespace.c:3726 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3802 do_mount fs/namespace.c:4125 [inline] __do_sys_mount fs/namespace.c:4324 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4301 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/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_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+0x1f9/0x6a0 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:3048 [inline] generic_file_write_iter+0x319/0x550 mm/filemap.c:4356 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.6.2106/15105: #0: ffff88807b7db438 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232 #1: ffff8880566c4420 (sb_writers#25){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3113 [inline] #1: ffff8880566c4420 (sb_writers#25){.+.+}-{0:0}, at: vfs_write+0x211/0xb30 fs/read_write.c:682 #2: ffff8880249db6a0 (&sb->s_type->i_mutex_key#34){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #2: ffff8880249db6a0 (&sb->s_type->i_mutex_key#34){++++}-{4:4}, at: hfs_file_fsync+0x9a/0x140 fs/hfs/inode.c:673 #3: ffff8880574620b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x184/0x200 fs/hfs/bfind.c:-1 stack backtrace: CPU: 1 UID: 0 PID: 15105 Comm: syz.6.2106 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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_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+0x1f9/0x6a0 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:3048 [inline] generic_file_write_iter+0x319/0x550 mm/filemap.c:4356 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: 0033:0x7f96ae98eba9 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:00007f96af7b5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f96aebd5fa0 RCX: 00007f96ae98eba9 RDX: 0000000000000e09 RSI: 0000200000000040 RDI: 0000000000000004 RBP: 00007f96aea11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f96aebd6038 R14: 00007f96aebd5fa0 R15: 00007ffe4fc6c7e8