loop7: detected capacity change from 0 to 1024 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.7.294/8421 is trying to acquire lock: ffff888067f580e8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0xa7/0xce0 fs/hfsplus/bitmap.c:35 but task is already holding lock: ffff8880223bcbf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x215/0x1d70 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+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:1022 [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:6374 hfsplus_symlink+0xc9/0x290 fs/hfsplus/dir.c:481 vfs_symlink+0x195/0x340 fs/namei.c:5615 filename_symlinkat+0x1cd/0x420 fs/namei.c:5640 __do_sys_symlink fs/namei.c:5667 [inline] __se_sys_symlink+0x4d/0x2b0 fs/namei.c:5663 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 (&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+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_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 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.7.294/8421: #0: ffff8880659660d0 (&type->s_umount_key#70/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345 #1: ffff888067f58178 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_fill_super+0x121b/0x19e0 fs/hfsplus/super.c:598 #2: ffff888028fda0a0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28 #3: ffff8880223bcbf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x215/0x1d70 fs/hfsplus/extents.c:453 stack backtrace: CPU: 1 UID: 0 PID: 8421 Comm: syz.7.294 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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_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 RIP: 0033:0x7f698e81da0a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f698ca6de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f698ca6dee0 RCX: 00007f698e81da0a RDX: 0000200000000100 RSI: 0000200000002900 RDI: 00007f698ca6dea0 RBP: 0000200000000100 R08: 00007f698ca6dee0 R09: 0000000002000010 R10: 0000000002000010 R11: 0000000000000246 R12: 0000200000002900 R13: 00007f698ca6dea0 R14: 00000000000006e5 R15: 0000200000000c00 hfsplus: catalog searching failed hfsplus: catalog searching failed hfsplus: catalog searching failed hfsplus: node 4:3 still has 2 user(s)!