loop2: detected capacity change from 0 to 1024 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.717/14190 is trying to acquire lock: ffff88803696c0e8 (&sbi->alloc_mutex){+.+.}-{4:4}, at: hfsplus_block_free+0xc7/0x630 fs/hfsplus/bitmap.c:182 but task is already holding lock: ffff888063f5ecf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_truncate+0x2d0/0xd20 fs/hfsplus/extents.c:577 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:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 hfsplus_get_block+0x391/0x1610 fs/hfsplus/extents.c:262 block_read_full_folio+0x29f/0x810 fs/buffer.c:2398 filemap_read_folio+0x12c/0x3a0 mm/filemap.c:2510 do_read_cache_folio+0x2bf/0x560 mm/filemap.c:4140 do_read_cache_page mm/filemap.c:4206 [inline] read_cache_page+0x5d/0x170 mm/filemap.c:4215 read_mapping_page include/linux/pagemap.h:1009 [inline] hfsplus_block_allocate+0xf7/0xd30 fs/hfsplus/bitmap.c:37 hfsplus_file_extend+0xb77/0x1df0 fs/hfsplus/extents.c:466 hfsplus_get_block+0x41f/0x1610 fs/hfsplus/extents.c:247 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2123 block_write_begin fs/buffer.c:2234 [inline] cont_write_begin+0x71b/0xac0 fs/buffer.c:2596 hfsplus_write_begin+0x66/0xb0 fs/hfsplus/inode.c:48 page_symlink+0x27a/0x440 fs/namei.c:6418 hfsplus_symlink+0xd3/0x390 fs/hfsplus/dir.c:478 vfs_symlink+0x18b/0x330 fs/namei.c:5656 filename_symlinkat+0x1cd/0x420 fs/namei.c:5681 __do_sys_symlink fs/namei.c:5708 [inline] __se_sys_symlink+0x4d/0x2b0 fs/namei.c:5704 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 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+0x1520/0x2ce0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 hfsplus_block_free+0xc7/0x630 fs/hfsplus/bitmap.c:182 hfsplus_free_extents+0x121/0xa50 fs/hfsplus/extents.c:362 hfsplus_file_truncate+0x7ef/0xd20 fs/hfsplus/extents.c:593 hfsplus_setattr+0x1b5/0x260 fs/hfsplus/inode.c:320 notify_change+0xbb8/0xec0 fs/attr.c:556 do_truncate+0x1c2/0x250 fs/open.c:68 handle_truncate fs/namei.c:4305 [inline] do_open fs/namei.c:4704 [inline] path_openat+0x3009/0x3850 fs/namei.c:4859 do_file_open+0x23e/0x4a0 fs/namei.c:4888 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 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.2.717/14190: #0: ffff8880336de500 (sb_writers#31){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494 #1: ffff888063f5eec8 (&sb->s_type->i_mutex_key#49){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1029 [inline] #1: ffff888063f5eec8 (&sb->s_type->i_mutex_key#49){+.+.}-{4:4}, at: do_truncate+0x18f/0x250 fs/open.c:63 #2: ffff888063f5ecf8 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_truncate+0x2d0/0xd20 fs/hfsplus/extents.c:577 stack backtrace: CPU: 1 UID: 0 PID: 14190 Comm: syz.2.717 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0x1520/0x2ce0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __mutex_lock_common kernel/locking/rtmutex_api.c:559 [inline] mutex_lock_nested+0x5a/0x1d0 kernel/locking/rtmutex_api.c:578 hfsplus_block_free+0xc7/0x630 fs/hfsplus/bitmap.c:182 hfsplus_free_extents+0x121/0xa50 fs/hfsplus/extents.c:362 hfsplus_file_truncate+0x7ef/0xd20 fs/hfsplus/extents.c:593 hfsplus_setattr+0x1b5/0x260 fs/hfsplus/inode.c:320 notify_change+0xbb8/0xec0 fs/attr.c:556 do_truncate+0x1c2/0x250 fs/open.c:68 handle_truncate fs/namei.c:4305 [inline] do_open fs/namei.c:4704 [inline] path_openat+0x3009/0x3850 fs/namei.c:4859 do_file_open+0x23e/0x4a0 fs/namei.c:4888 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1973cace59 Code: ff c3 66 2e 0f 1f 84 00 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 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1971efe028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1973f25fa0 RCX: 00007f1973cace59 RDX: 0000000000183341 RSI: 0000200000000080 RDI: ffffffffffffff9c RBP: 00007f1973d42e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000045 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1973f26038 R14: 00007f1973f25fa0 R15: 00007ffc011b2098