====================================================== WARNING: possible circular locking dependency detected 6.15.0-syzkaller-01958-g785cdec46e92 #0 Not tainted ------------------------------------------------------ syz.3.43/6191 is trying to acquire lock: ffff88805ba358f8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_allocate+0x94/0x9b0 fs/hfsplus/bitmap.c:35 but task is already holding lock: ffff88805ba1b708 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 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}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746 hfsplus_get_block+0x39e/0x1530 fs/hfsplus/extents.c:260 block_read_full_folio+0x29f/0x830 fs/buffer.c:2427 filemap_read_folio+0x114/0x380 mm/filemap.c:2401 do_read_cache_folio+0x350/0x590 mm/filemap.c:3885 do_read_cache_page mm/filemap.c:3951 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:3960 read_mapping_page include/linux/pagemap.h:989 [inline] hfsplus_block_allocate+0xe4/0x9b0 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xae3/0x1990 fs/hfsplus/extents.c:469 hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245 __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2151 block_write_begin fs/buffer.c:2262 [inline] cont_write_begin+0x789/0xb50 fs/buffer.c:2601 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46 page_symlink+0x26c/0x430 fs/namei.c:5511 hfsplus_symlink+0xca/0x260 fs/hfsplus/dir.c:449 vfs_symlink+0x140/0x2f0 fs/namei.c:4730 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4756 __do_sys_symlink fs/namei.c:4777 [inline] __se_sys_symlink fs/namei.c:4775 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4775 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x220 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:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746 hfsplus_block_allocate+0x94/0x9b0 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xae3/0x1990 fs/hfsplus/extents.c:469 hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245 __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2151 block_write_begin fs/buffer.c:2262 [inline] cont_write_begin+0x789/0xb50 fs/buffer.c:2601 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46 cont_expand_zero fs/buffer.c:2528 [inline] cont_write_begin+0x2fa/0xb50 fs/buffer.c:2591 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46 generic_cont_expand_simple+0x13f/0x210 fs/buffer.c:2492 hfsplus_setattr+0x169/0x270 fs/hfsplus/inode.c:258 notify_change+0xb36/0xe40 fs/attr.c:552 do_truncate+0x1a4/0x220 fs/open.c:68 vfs_truncate+0x493/0x520 fs/open.c:118 do_sys_truncate+0xdb/0x190 fs/open.c:141 __do_sys_truncate fs/open.c:153 [inline] __se_sys_truncate fs/open.c:151 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:151 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x220 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 *** 3 locks held by syz.3.43/6191: #0: ffff888011aaa428 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff88805ba1b8f8 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: inode_lock_killable include/linux/fs.h:872 [inline] #1: ffff88805ba1b8f8 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: do_truncate+0x171/0x220 fs/open.c:63 #2: ffff88805ba1b708 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1fc/0x1990 fs/hfsplus/extents.c:458 stack backtrace: CPU: 0 UID: 0 PID: 6191 Comm: syz.3.43 Not tainted 6.15.0-syzkaller-01958-g785cdec46e92 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __mutex_lock_common kernel/locking/mutex.c:601 [inline] __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:746 hfsplus_block_allocate+0x94/0x9b0 fs/hfsplus/bitmap.c:35 hfsplus_file_extend+0xae3/0x1990 fs/hfsplus/extents.c:469 hfsplus_get_block+0x411/0x1530 fs/hfsplus/extents.c:245 __block_write_begin_int+0x6b2/0x1900 fs/buffer.c:2151 block_write_begin fs/buffer.c:2262 [inline] cont_write_begin+0x789/0xb50 fs/buffer.c:2601 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46 cont_expand_zero fs/buffer.c:2528 [inline] cont_write_begin+0x2fa/0xb50 fs/buffer.c:2591 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:46 generic_cont_expand_simple+0x13f/0x210 fs/buffer.c:2492 hfsplus_setattr+0x169/0x270 fs/hfsplus/inode.c:258 notify_change+0xb36/0xe40 fs/attr.c:552 do_truncate+0x1a4/0x220 fs/open.c:68 vfs_truncate+0x493/0x520 fs/open.c:118 do_sys_truncate+0xdb/0x190 fs/open.c:141 __do_sys_truncate fs/open.c:153 [inline] __se_sys_truncate fs/open.c:151 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:151 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x220 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2d21d8e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2d22c14038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007f2d21fb6080 RCX: 00007f2d21d8e969 RDX: 0000000000000000 RSI: 0000000000001101 RDI: 0000200000000000 RBP: 00007f2d21e10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2d21fb6080 R15: 00007ffe86b6c318