loop4: detected capacity change from 0 to 64 ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0 Not tainted ------------------------------------------------------ syz.4.600/8014 is trying to acquire lock: ffff88807f62c1f8 (&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: ffff8880789560b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x165/0x1e0 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){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 hfs_find_init+0x165/0x1e0 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:2427 filemap_read_folio+0x117/0x380 mm/filemap.c:2412 do_read_cache_folio+0x350/0x590 mm/filemap.c:3894 do_read_cache_page mm/filemap.c:3960 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:3969 read_mapping_page include/linux/pagemap.h:966 [inline] __hfs_bnode_create+0x4a8/0x7f0 fs/hfs/bnode.c:296 hfs_bnode_find+0x224/0xd00 fs/hfs/bnode.c:341 hfs_brec_find+0x159/0x500 fs/hfs/bfind.c:126 hfs_brec_read+0x24/0x110 fs/hfs/bfind.c:165 hfs_cat_find_brec+0x15c/0x3f0 fs/hfs/catalog.c:194 hfs_fill_super+0x426/0x640 fs/hfs/super.c:350 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1681 vfs_get_tree+0x92/0x2b0 fs/super.c:1804 do_new_mount+0x24a/0xa40 fs/namespace.c:3902 do_mount fs/namespace.c:4239 [inline] __do_sys_mount fs/namespace.c:4450 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4427 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 (&HFS_I(tree->inode)->extents_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 hfs_extend_file+0xda/0x1230 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+0x316/0x1230 fs/hfs/extent.c:401 hfs_get_block+0x3d7/0xbd0 fs/hfs/extent.c:353 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2151 block_write_begin fs/buffer.c:2262 [inline] cont_write_begin+0x789/0xb50 fs/buffer.c:2601 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52 generic_perform_write+0x2c7/0x910 mm/filemap.c:4112 generic_file_write_iter+0x10f/0x540 mm/filemap.c:4255 do_iter_readv_writev+0x56e/0x7f0 fs/read_write.c:-1 vfs_writev+0x31a/0x960 fs/read_write.c:1057 do_writev+0x14d/0x2d0 fs/read_write.c:1103 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 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 *** 5 locks held by syz.4.600/8014: #0: ffff88803167ab78 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1217 #1: ffff888078954428 (sb_writers#30){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline] #1: ffff888078954428 (sb_writers#30){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055 #2: ffff88807f62d720 (&sb->s_type->i_mutex_key#41){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #2: ffff88807f62d720 (&sb->s_type->i_mutex_key#41){+.+.}-{4:4}, at: generic_file_write_iter+0xe3/0x540 mm/filemap.c:4252 #3: ffff88807f62d578 (&HFS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfs_extend_file+0xda/0x1230 fs/hfs/extent.c:397 #4: ffff8880789560b0 (&tree->tree_lock#2/1){+.+.}-{4:4}, at: hfs_find_init+0x165/0x1e0 fs/hfs/bfind.c:-1 stack backtrace: CPU: 1 UID: 0 PID: 8014 Comm: syz.4.600 Not tainted 6.16.0-rc5-syzkaller-00053-g8c2e52ebbe88 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747 hfs_extend_file+0xda/0x1230 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+0x316/0x1230 fs/hfs/extent.c:401 hfs_get_block+0x3d7/0xbd0 fs/hfs/extent.c:353 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2151 block_write_begin fs/buffer.c:2262 [inline] cont_write_begin+0x789/0xb50 fs/buffer.c:2601 hfs_write_begin+0x66/0xb0 fs/hfs/inode.c:52 generic_perform_write+0x2c7/0x910 mm/filemap.c:4112 generic_file_write_iter+0x10f/0x540 mm/filemap.c:4255 do_iter_readv_writev+0x56e/0x7f0 fs/read_write.c:-1 vfs_writev+0x31a/0x960 fs/read_write.c:1057 do_writev+0x14d/0x2d0 fs/read_write.c:1103 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 RIP: 0033:0x7f5cb158e929 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:00007f5cb24da038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f5cb17b5fa0 RCX: 00007f5cb158e929 RDX: 0000000000000001 RSI: 0000200000000140 RDI: 0000000000000004 RBP: 00007f5cb1610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5cb17b5fa0 R15: 00007ffdee398158 bio_check_eod: 227 callbacks suppressed syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=65, nr_sectors = 1 limit=64 buffer_io_error: 217 callbacks suppressed Buffer I/O error on dev loop4, logical block 65, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=66, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 66, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=67, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 67, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=68, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 68, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=72, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 72, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=73, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 73, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=76, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 76, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=77, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 77, lost async page write syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=78, nr_sectors = 504 limit=64 syz.4.600: attempt to access beyond end of device loop4: rw=2049, sector=582, nr_sectors = 1 limit=64 Buffer I/O error on dev loop4, logical block 582, lost async page write Buffer I/O error on dev loop4, logical block 583, lost async page write bond0: (slave syz_tun): Releasing backup interface