====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.5.868/7354 is trying to acquire lock: ffff88805854c488 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_get_block+0x38f/0x1520 fs/hfsplus/extents.c:260 but task is already holding lock: ffff8880250af8f8 (&sbi->alloc_mutex){+.+.}-{3:3}, at: hfsplus_block_allocate+0x8e/0x900 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){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xae0 kernel/locking/mutex.c:747 hfsplus_block_free+0xbf/0x4b0 fs/hfsplus/bitmap.c:182 hfsplus_free_extents+0x10d/0xa50 fs/hfsplus/extents.c:360 hfsplus_file_truncate+0x756/0xb60 fs/hfsplus/extents.c:589 hfsplus_delete_inode+0x17c/0x230 fs/hfsplus/inode.c:-1 hfsplus_unlink+0x52b/0x800 fs/hfsplus/dir.c:405 vfs_unlink+0x376/0x600 fs/namei.c:4330 do_unlinkat+0x335/0x580 fs/namei.c:4398 __do_sys_unlink fs/namei.c:4446 [inline] __se_sys_unlink fs/namei.c:4444 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4444 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2d18/0x7c40 kernel/locking/lockdep.c:5063 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xae0 kernel/locking/mutex.c:747 hfsplus_get_block+0x38f/0x1520 fs/hfsplus/extents.c:260 block_read_full_folio+0x405/0xf80 fs/buffer.c:2271 filemap_read_folio+0x164/0x7a0 mm/filemap.c:2490 do_read_cache_folio+0x29e/0x790 mm/filemap.c:3659 do_read_cache_page+0x32/0x230 mm/filemap.c:3701 read_mapping_page include/linux/pagemap.h:793 [inline] hfsplus_block_allocate+0xe3/0x900 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xb17/0x1a40 fs/hfsplus/extents.c:466 hfsplus_get_block+0x41d/0x1520 fs/hfsplus/extents.c:245 __block_write_begin_int+0x577/0x1ab0 fs/buffer.c:1991 __block_write_begin fs/buffer.c:2041 [inline] block_write_begin+0x96/0x1e0 fs/buffer.c:2102 cont_write_begin+0x5f9/0x800 fs/buffer.c:2456 hfsplus_write_begin+0x87/0xd0 fs/hfsplus/inode.c:52 generic_perform_write+0x2fa/0x5c0 mm/filemap.c:3862 __generic_file_write_iter+0x148/0x2a0 mm/filemap.c:3960 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:3989 __kernel_write_iter+0x298/0x690 fs/read_write.c:517 __kernel_write+0x103/0x170 fs/read_write.c:537 __dump_emit+0x210/0x310 fs/coredump.c:873 elf_core_dump+0x287e/0x3630 fs/binfmt_elf.c:2306 do_coredump+0x16c1/0x2480 fs/coredump.c:824 get_signal+0x1093/0x1340 kernel/signal.c:2858 arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1485 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 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 *** 4 locks held by syz.5.868/7354: #0: ffff8880772aa460 (sb_writers#18){.+.+}-{0:0}, at: do_coredump+0x169d/0x2480 fs/coredump.c:823 #1: ffff88807ee22b80 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #1: ffff88807ee22b80 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: generic_file_write_iter+0x7f/0x2e0 mm/filemap.c:3986 #2: ffff88807ee22988 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1ca/0x1a40 fs/hfsplus/extents.c:455 #3: ffff8880250af8f8 (&sbi->alloc_mutex){+.+.}-{3:3}, at: hfsplus_block_allocate+0x8e/0x900 fs/hfsplus/bitmap.c:35 stack backtrace: CPU: 0 PID: 7354 Comm: syz.5.868 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2d18/0x7c40 kernel/locking/lockdep.c:5063 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xae0 kernel/locking/mutex.c:747 hfsplus_get_block+0x38f/0x1520 fs/hfsplus/extents.c:260 block_read_full_folio+0x405/0xf80 fs/buffer.c:2271 filemap_read_folio+0x164/0x7a0 mm/filemap.c:2490 do_read_cache_folio+0x29e/0x790 mm/filemap.c:3659 do_read_cache_page+0x32/0x230 mm/filemap.c:3701 read_mapping_page include/linux/pagemap.h:793 [inline] hfsplus_block_allocate+0xe3/0x900 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xb17/0x1a40 fs/hfsplus/extents.c:466 hfsplus_get_block+0x41d/0x1520 fs/hfsplus/extents.c:245 __block_write_begin_int+0x577/0x1ab0 fs/buffer.c:1991 __block_write_begin fs/buffer.c:2041 [inline] block_write_begin+0x96/0x1e0 fs/buffer.c:2102 cont_write_begin+0x5f9/0x800 fs/buffer.c:2456 hfsplus_write_begin+0x87/0xd0 fs/hfsplus/inode.c:52 generic_perform_write+0x2fa/0x5c0 mm/filemap.c:3862 __generic_file_write_iter+0x148/0x2a0 mm/filemap.c:3960 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:3989 __kernel_write_iter+0x298/0x690 fs/read_write.c:517 __kernel_write+0x103/0x170 fs/read_write.c:537 __dump_emit+0x210/0x310 fs/coredump.c:873 elf_core_dump+0x287e/0x3630 fs/binfmt_elf.c:2306 do_coredump+0x16c1/0x2480 fs/coredump.c:824 get_signal+0x1093/0x1340 kernel/signal.c:2858 arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1485 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f415b79de61 Code: 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 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f415ba26090 RCX: 00007f415b79de59 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007f415b833e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f415ba26128 R14: 00007f415ba26090 R15: 00007ffcbbbc76c8 syz.5.868 (7354) used greatest stack depth: 19984 bytes left