loop3: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected 6.6.97-syzkaller #0 Not tainted ------------------------------------------------------ syz.3.251/6926 is trying to acquire lock: ffff88802d648778 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xdb/0x1220 fs/hfs/extent.c:397 but task is already holding lock: ffff88807ca220b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15f/0x1d0 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+0x129/0xcc0 kernel/locking/mutex.c:747 hfs_find_init+0x15f/0x1d0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_get_block+0x51c/0xbd0 fs/hfs/extent.c:366 block_read_full_folio+0x42e/0xf40 fs/buffer.c:2406 filemap_read_folio+0x167/0x760 mm/filemap.c:2420 do_read_cache_folio+0x470/0x7e0 mm/filemap.c:3789 do_read_cache_page+0x32/0x250 mm/filemap.c:3855 read_mapping_page include/linux/pagemap.h:892 [inline] __hfs_bnode_create+0x4a9/0x790 fs/hfs/bnode.c:296 hfs_bnode_find+0x222/0xcc0 fs/hfs/bnode.c:341 hfs_brec_find+0x15a/0x500 fs/hfs/bfind.c:126 hfs_brec_read+0x24/0x110 fs/hfs/bfind.c:165 hfs_cat_find_brec+0x15d/0x3f0 fs/hfs/catalog.c:194 hfs_fill_super+0xdd5/0x1320 fs/hfs/super.c:419 mount_bdev+0x22b/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3366 do_mount fs/namespace.c:3706 [inline] __do_sys_mount fs/namespace.c:3915 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3892 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 hfs_extend_file+0xdb/0x1220 fs/hfs/extent.c:397 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x317/0x1220 fs/hfs/extent.c:401 hfs_get_block+0x3d8/0xbd0 fs/hfs/extent.c:353 __block_write_begin_int+0x566/0x1ad0 fs/buffer.c:2124 __block_write_begin fs/buffer.c:2173 [inline] block_write_begin+0x9a/0x1e0 fs/buffer.c:2234 cont_write_begin+0x5c8/0x7e0 fs/buffer.c:2591 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:58 cont_expand_zero fs/buffer.c:2518 [inline] cont_write_begin+0x2ad/0x7e0 fs/buffer.c:2581 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:58 generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4016 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4137 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 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+0x195/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 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 *** 4 locks held by syz.3.251/6926: #0: ffff888066500418 (sb_writers#19){.+.+}-{0:0}, at: vfs_write+0x20e/0x940 fs/read_write.c:580 #1: ffff88802d649cb8 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff88802d649cb8 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: generic_file_write_iter+0x83/0x2e0 mm/filemap.c:4134 #2: ffff88802d649af8 (&HFS_I(inode)->extents_lock#2){+.+.}-{3:3}, at: hfs_extend_file+0xdb/0x1220 fs/hfs/extent.c:397 #3: ffff88807ca220b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15f/0x1d0 fs/hfs/bfind.c:-1 stack backtrace: CPU: 0 PID: 6926 Comm: syz.3.251 Not tainted 6.6.97-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_noncircular+0x2bd/0x3c0 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 hfs_extend_file+0xdb/0x1220 fs/hfs/extent.c:397 hfs_bmap_reserve+0x107/0x430 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x317/0x1220 fs/hfs/extent.c:401 hfs_get_block+0x3d8/0xbd0 fs/hfs/extent.c:353 __block_write_begin_int+0x566/0x1ad0 fs/buffer.c:2124 __block_write_begin fs/buffer.c:2173 [inline] block_write_begin+0x9a/0x1e0 fs/buffer.c:2234 cont_write_begin+0x5c8/0x7e0 fs/buffer.c:2591 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:58 cont_expand_zero fs/buffer.c:2518 [inline] cont_write_begin+0x2ad/0x7e0 fs/buffer.c:2581 hfs_write_begin+0x8b/0xd0 fs/hfs/inode.c:58 generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4016 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4137 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 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+0x195/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fce4e78e929 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:00007fce4f6d7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007fce4e9b5fa0 RCX: 00007fce4e78e929 RDX: 0000000000000001 RSI: 0000200000000940 RDI: 0000000000000005 RBP: 00007fce4e810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008000c61 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fce4e9b5fa0 R15: 00007ffcd5d77dd8