loop1: detected capacity change from 0 to 1024 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.174/6935 is trying to acquire lock: ffff8880343738e8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0xa7/0xc40 fs/hfsplus/bitmap.c:35 but task is already holding lock: ffff8880389c7178 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1f8/0x1ba0 fs/hfsplus/extents.c:453 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/rtmutex_api.c:533 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:552 hfsplus_get_block+0x39a/0x15e0 fs/hfsplus/extents.c:260 block_read_full_folio+0x29f/0x830 fs/buffer.c:2420 filemap_read_folio+0x117/0x380 mm/filemap.c:2489 do_read_cache_folio+0x2ba/0x560 mm/filemap.c:4082 do_read_cache_page mm/filemap.c:4148 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:4157 read_mapping_page include/linux/pagemap.h:1003 [inline] hfsplus_block_allocate+0xf3/0xc40 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xa9a/0x1ba0 fs/hfsplus/extents.c:464 hfsplus_get_block+0x40c/0x15e0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x6b5/0x1900 fs/buffer.c:2145 block_write_begin fs/buffer.c:2256 [inline] cont_write_begin+0x789/0xb50 fs/buffer.c:2594 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:48 page_symlink+0x26f/0x430 fs/namei.c:6277 hfsplus_symlink+0xca/0x260 fs/hfsplus/dir.c:449 vfs_symlink+0x29a/0x2d0 fs/namei.c:5514 do_symlinkat+0x1f5/0x3d0 fs/namei.c:5541 __do_sys_symlink fs/namei.c:5567 [inline] __se_sys_symlink fs/namei.c:5565 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:5565 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&sbi->alloc_mutex){+.+.}-{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+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x340 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_block_allocate+0xa7/0xc40 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xa9a/0x1ba0 fs/hfsplus/extents.c:464 hfsplus_bmap_reserve+0x125/0x500 fs/hfsplus/btree.c:358 hfsplus_create_cat+0x18e/0x1130 fs/hfsplus/catalog.c:272 hfsplus_fill_super+0x12fd/0x1b60 fs/hfsplus/super.c:580 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1699 vfs_get_tree+0x92/0x2a0 fs/super.c:1759 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/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(&HFSPLUS_I(inode)->extents_lock); lock(&sbi->alloc_mutex); lock(&HFSPLUS_I(inode)->extents_lock); lock(&sbi->alloc_mutex); *** DEADLOCK *** 4 locks held by syz.1.174/6935: #0: ffff88801a3900d0 (&type->s_umount_key#52/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:344 #1: ffff888034373978 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_fill_super+0x1280/0x1b60 fs/hfsplus/super.c:573 #2: ffff888038d9e0a0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x290 fs/hfsplus/bfind.c:28 #3: ffff8880389c7178 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1f8/0x1ba0 fs/hfsplus/extents.c:453 stack backtrace: CPU: 0 UID: 0 PID: 6935 Comm: syz.1.174 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 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+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x117/0x340 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_block_allocate+0xa7/0xc40 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xa9a/0x1ba0 fs/hfsplus/extents.c:464 hfsplus_bmap_reserve+0x125/0x500 fs/hfsplus/btree.c:358 hfsplus_create_cat+0x18e/0x1130 fs/hfsplus/catalog.c:272 hfsplus_fill_super+0x12fd/0x1b60 fs/hfsplus/super.c:580 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1699 vfs_get_tree+0x92/0x2a0 fs/super.c:1759 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3158510eea Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f315676de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f315676def0 RCX: 00007f3158510eea RDX: 0000200000000000 RSI: 0000200000000080 RDI: 00007f315676deb0 RBP: 0000200000000000 R08: 00007f315676def0 R09: 0000000000200000 R10: 0000000000200000 R11: 0000000000000246 R12: 0000200000000080 R13: 00007f315676deb0 R14: 000000000000070a R15: 00002000000023c0