loop8: detected capacity change from 0 to 1024 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.8.10941/32164 is trying to acquire lock: ffff88805881b048 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 but task is already holding lock: ffff8880509420b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&tree->tree_lock/1){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776 hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 hfsplus_file_truncate+0x2c5/0xce0 fs/hfsplus/extents.c:579 hfsplus_delete_inode+0x194/0x230 fs/hfsplus/inode.c:502 hfsplus_unlink+0x79c/0x9a0 fs/hfsplus/dir.c:426 vfs_unlink+0x2f0/0xbd0 fs/namei.c:5470 filename_unlinkat+0x408/0x730 fs/namei.c:5540 __do_sys_unlinkat fs/namei.c:5569 [inline] __se_sys_unlinkat fs/namei.c:5561 [inline] __x64_sys_unlinkat+0xc0/0x130 fs/namei.c:5561 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{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+0x14b8/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776 hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 hfsplus_bmap_reserve+0x322/0x420 fs/hfsplus/btree.c:358 __hfsplus_ext_write_extent+0x474/0x5e0 fs/hfsplus/extents.c:104 __hfsplus_ext_cache_extent+0x98/0x9d0 fs/hfsplus/extents.c:186 hfsplus_ext_read_extent+0x200/0x250 fs/hfsplus/extents.c:218 hfsplus_file_extend+0x719/0x11d0 fs/hfsplus/extents.c:457 hfsplus_get_block+0x1a9/0xab0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x57a/0x19c0 fs/buffer.c:2146 block_write_begin+0x9d/0x1d0 fs/buffer.c:2257 cont_write_begin+0x573/0xa10 fs/buffer.c:2595 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 generic_perform_write+0x292/0xa40 mm/filemap.c:4314 __generic_file_write_iter+0x1f7/0x240 mm/filemap.c:4431 generic_file_write_iter+0xe1/0x3d0 mm/filemap.c:4457 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1070 fs/read_write.c:688 ksys_write+0x12a/0x250 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 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(&tree->tree_lock/1); lock(&HFSPLUS_I(inode)->extents_lock); lock(&tree->tree_lock/1); lock(&HFSPLUS_I(inode)->extents_lock); *** DEADLOCK *** 5 locks held by syz.8.10941/32164: #0: ffff888078ad70b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1255 #1: ffff88807ac42420 (sb_writers#21){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740 #2: ffff88805881cd38 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #2: ffff88805881cd38 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: generic_file_write_iter+0x8c/0x3d0 mm/filemap.c:4454 #3: ffff88805881cb48 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 #4: ffff8880509420b0 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 stack backtrace: CPU: 0 UID: 0 PID: 32164 Comm: syz.8.10941 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 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+0x14b8/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x1a2/0x1b90 kernel/locking/mutex.c:776 hfsplus_file_extend+0x1c2/0x11d0 fs/hfsplus/extents.c:453 hfsplus_bmap_reserve+0x322/0x420 fs/hfsplus/btree.c:358 __hfsplus_ext_write_extent+0x474/0x5e0 fs/hfsplus/extents.c:104 __hfsplus_ext_cache_extent+0x98/0x9d0 fs/hfsplus/extents.c:186 hfsplus_ext_read_extent+0x200/0x250 fs/hfsplus/extents.c:218 hfsplus_file_extend+0x719/0x11d0 fs/hfsplus/extents.c:457 hfsplus_get_block+0x1a9/0xab0 fs/hfsplus/extents.c:245 __block_write_begin_int+0x57a/0x19c0 fs/buffer.c:2146 block_write_begin+0x9d/0x1d0 fs/buffer.c:2257 cont_write_begin+0x573/0xa10 fs/buffer.c:2595 hfsplus_write_begin+0x64/0x120 fs/hfsplus/inode.c:48 generic_perform_write+0x292/0xa40 mm/filemap.c:4314 __generic_file_write_iter+0x1f7/0x240 mm/filemap.c:4431 generic_file_write_iter+0xe1/0x3d0 mm/filemap.c:4457 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1070 fs/read_write.c:688 ksys_write+0x12a/0x250 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f72ffd9bf79 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:00007f7300c81028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7300015fa0 RCX: 00007f72ffd9bf79 RDX: 000000000208e24b RSI: 0000200000000040 RDI: 0000000000000004 RBP: 00007f72ffe327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7300016038 R14: 00007f7300015fa0 R15: 00007ffe7e6426f8