loop3: detected capacity change from 0 to 1024 ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc5-syzkaller-gc32f8dc5aaf9 #0 Not tainted ------------------------------------------------------ syz.3.964/9003 is trying to acquire lock: ffff0000f2da50f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x88/0x70c fs/hfsplus/bitmap.c:35 but task is already holding lock: ffff0000c40ba988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1b8/0x1388 fs/hfsplus/extents.c:458 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+0x1d0/0x2190 kernel/locking/mutex.c:601 __mutex_lock kernel/locking/mutex.c:746 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:798 hfsplus_get_block+0x2bc/0x1154 fs/hfsplus/extents.c:260 block_read_full_folio+0x2ec/0x824 fs/buffer.c:2427 hfsplus_read_folio+0x28/0x38 fs/hfsplus/inode.c:28 filemap_read_folio+0xec/0x2f8 mm/filemap.c:2401 do_read_cache_folio+0x368/0x5c0 mm/filemap.c:3885 do_read_cache_page mm/filemap.c:3951 [inline] read_cache_page+0x6c/0x160 mm/filemap.c:3960 read_mapping_page include/linux/pagemap.h:989 [inline] hfsplus_block_allocate+0xdc/0x70c fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0x770/0x1388 fs/hfsplus/extents.c:469 hfsplus_get_block+0x314/0x1154 fs/hfsplus/extents.c:245 __block_write_begin_int+0x53c/0x15e8 fs/buffer.c:2151 block_write_begin fs/buffer.c:2262 [inline] cont_write_begin+0x62c/0x968 fs/buffer.c:2601 hfsplus_write_begin+0x7c/0xc4 fs/hfsplus/inode.c:46 generic_perform_write+0x23c/0x79c mm/filemap.c:4103 __generic_file_write_iter+0xfc/0x204 mm/filemap.c:4220 generic_file_write_iter+0x104/0x470 mm/filemap.c:4246 __kernel_write_iter+0x2b8/0x6c8 fs/read_write.c:617 __kernel_write+0xe0/0x130 fs/read_write.c:637 __dump_emit fs/coredump.c:808 [inline] dump_emit+0x220/0x31c fs/coredump.c:845 elf_core_dump+0x22a0/0x2f40 fs/binfmt_elf.c:2080 do_coredump+0x17e8/0x22c0 fs/coredump.c:759 get_signal+0xe38/0x12f8 kernel/signal.c:3019 do_signal+0x1c0/0x4438 arch/arm64/kernel/signal.c:1615 do_notify_resume+0xac/0x1ec arch/arm64/kernel/entry-common.c:148 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_undef+0xb0/0x150 arch/arm64/kernel/entry-common.c:715 el0t_64_sync_handler+0x90/0x108 arch/arm64/kernel/entry-common.c:817 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #0 (&sbi->alloc_mutex){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x1728/0x3058 kernel/locking/lockdep.c:5235 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5866 __mutex_lock_common+0x1d0/0x2190 kernel/locking/mutex.c:601 __mutex_lock kernel/locking/mutex.c:746 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:798 hfsplus_block_allocate+0x88/0x70c fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0x770/0x1388 fs/hfsplus/extents.c:469 hfsplus_bmap_reserve+0xe8/0x494 fs/hfsplus/btree.c:358 hfsplus_create_cat+0x170/0xdc8 fs/hfsplus/catalog.c:272 hfsplus_fill_super+0xfbc/0x1714 fs/hfsplus/super.c:561 get_tree_bdev_flags+0x360/0x414 fs/super.c:1636 get_tree_bdev+0x2c/0x3c fs/super.c:1659 hfsplus_get_tree+0x28/0x38 fs/hfsplus/super.c:640 vfs_get_tree+0x90/0x28c fs/super.c:1759 do_new_mount+0x228/0x814 fs/namespace.c:3884 path_mount+0x5b4/0xde0 fs/namespace.c:4211 do_mount fs/namespace.c:4224 [inline] __do_sys_mount fs/namespace.c:4435 [inline] __se_sys_mount fs/namespace.c:4412 [inline] __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4412 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 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.3.964/9003: #0: ffff0000cc0100e0 (&type->s_umount_key#66/1){+.+.}-{4:4}, at: alloc_super+0x1a0/0x80c fs/super.c:344 #1: ffff0000f2da5198 (&sbi->vh_mutex){+.+.}-{4:4}, at: hfsplus_fill_super+0xf64/0x1714 fs/hfsplus/super.c:554 #2: ffff0001037ac0b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x144/0x1bc fs/hfsplus/bfind.c:28 #3: ffff0000c40ba988 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1b8/0x1388 fs/hfsplus/extents.c:458 stack backtrace: CPU: 1 UID: 0 PID: 9003 Comm: syz.3.964 Not tainted 6.15.0-rc5-syzkaller-gc32f8dc5aaf9 #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x324/0x32c kernel/locking/lockdep.c:2079 check_noncircular+0x154/0x174 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain kernel/locking/lockdep.c:3909 [inline] __lock_acquire+0x1728/0x3058 kernel/locking/lockdep.c:5235 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5866 __mutex_lock_common+0x1d0/0x2190 kernel/locking/mutex.c:601 __mutex_lock kernel/locking/mutex.c:746 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:798 hfsplus_block_allocate+0x88/0x70c fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0x770/0x1388 fs/hfsplus/extents.c:469 hfsplus_bmap_reserve+0xe8/0x494 fs/hfsplus/btree.c:358 hfsplus_create_cat+0x170/0xdc8 fs/hfsplus/catalog.c:272 hfsplus_fill_super+0xfbc/0x1714 fs/hfsplus/super.c:561 get_tree_bdev_flags+0x360/0x414 fs/super.c:1636 get_tree_bdev+0x2c/0x3c fs/super.c:1659 hfsplus_get_tree+0x28/0x38 fs/hfsplus/super.c:640 vfs_get_tree+0x90/0x28c fs/super.c:1759 do_new_mount+0x228/0x814 fs/namespace.c:3884 path_mount+0x5b4/0xde0 fs/namespace.c:4211 do_mount fs/namespace.c:4224 [inline] __do_sys_mount fs/namespace.c:4435 [inline] __se_sys_mount fs/namespace.c:4412 [inline] __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4412 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600