loop4: detected capacity change from 0 to 1024 hfsplus: b-tree write err: -5, ino 2 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.4.358/9436 is trying to acquire lock: ffff8880641a3cf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_get_block+0x3a0/0x1670 fs/hfsplus/extents.c:260 but task is already holding lock: ffff88803fd190e8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0xa7/0xce0 fs/hfsplus/bitmap.c:35 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sbi->alloc_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfsplus_block_allocate+0xa7/0xce0 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xb2d/0x1d70 fs/hfsplus/extents.c:464 hfsplus_bmap_reserve+0x128/0x520 fs/hfsplus/btree.c:358 hfsplus_create_cat+0x1e2/0x11c0 fs/hfsplus/catalog.c:272 hfsplus_fill_super+0x129a/0x19e0 fs/hfsplus/super.c:605 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3839 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&HFSPLUS_I(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 kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfsplus_get_block+0x3a0/0x1670 fs/hfsplus/extents.c:260 block_read_full_folio+0x29f/0x830 fs/buffer.c:2417 filemap_read_folio+0x137/0x3b0 mm/filemap.c:2501 do_read_cache_folio+0x2bf/0x560 mm/filemap.c:4101 do_read_cache_page mm/filemap.c:4167 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:4176 read_mapping_page include/linux/pagemap.h:1011 [inline] hfsplus_block_allocate+0xf3/0xce0 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xb2d/0x1d70 fs/hfsplus/extents.c:464 hfsplus_get_block+0x42e/0x1670 fs/hfsplus/extents.c:245 __block_write_begin_int+0x6c6/0x1910 fs/buffer.c:2142 block_write_begin fs/buffer.c:2253 [inline] cont_write_begin+0x737/0xae0 fs/buffer.c:2591 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:48 page_symlink+0x27a/0x440 fs/namei.c:6380 hfsplus_symlink+0xc9/0x290 fs/hfsplus/dir.c:481 vfs_symlink+0x195/0x340 fs/namei.c:5621 filename_symlinkat+0x1cd/0x420 fs/namei.c:5646 __do_sys_symlink fs/namei.c:5673 [inline] __se_sys_symlink+0x4d/0x2b0 fs/namei.c:5669 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 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(&sbi->alloc_mutex); lock(&HFSPLUS_I(inode)->extents_lock); lock(&sbi->alloc_mutex); lock(&HFSPLUS_I(inode)->extents_lock); *** DEADLOCK *** 5 locks held by syz.4.358/9436: #0: ffff88805ddca480 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff8880641a37d8 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff8880641a37d8 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline] #1: ffff8880641a37d8 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline] #1: ffff8880641a37d8 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928 #2: ffff88803fd19178 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_symlink+0x81/0x290 fs/hfsplus/dir.c:476 #3: ffff88803dc13cf8 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x215/0x1d70 fs/hfsplus/extents.c:453 #4: ffff88803fd190e8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0xa7/0xce0 fs/hfsplus/bitmap.c:35 stack backtrace: CPU: 1 UID: 0 PID: 9436 Comm: syz.4.358 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 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 kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfsplus_get_block+0x3a0/0x1670 fs/hfsplus/extents.c:260 block_read_full_folio+0x29f/0x830 fs/buffer.c:2417 filemap_read_folio+0x137/0x3b0 mm/filemap.c:2501 do_read_cache_folio+0x2bf/0x560 mm/filemap.c:4101 do_read_cache_page mm/filemap.c:4167 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:4176 read_mapping_page include/linux/pagemap.h:1011 [inline] hfsplus_block_allocate+0xf3/0xce0 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xb2d/0x1d70 fs/hfsplus/extents.c:464 hfsplus_get_block+0x42e/0x1670 fs/hfsplus/extents.c:245 __block_write_begin_int+0x6c6/0x1910 fs/buffer.c:2142 block_write_begin fs/buffer.c:2253 [inline] cont_write_begin+0x737/0xae0 fs/buffer.c:2591 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:48 page_symlink+0x27a/0x440 fs/namei.c:6380 hfsplus_symlink+0xc9/0x290 fs/hfsplus/dir.c:481 vfs_symlink+0x195/0x340 fs/namei.c:5621 filename_symlinkat+0x1cd/0x420 fs/namei.c:5646 __do_sys_symlink fs/namei.c:5673 [inline] __se_sys_symlink+0x4d/0x2b0 fs/namei.c:5669 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7febb184c819 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:00007febafa9e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 00007febb1ac5fa0 RCX: 00007febb184c819 RDX: 0000000000000000 RSI: 0000200000000cc0 RDI: 000020000000a900 RBP: 00007febb18e2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007febb1ac6038 R14: 00007febb1ac5fa0 R15: 00007ffe97baead8