============================================ WARNING: possible recursive locking detected syzkaller #0 Not tainted -------------------------------------------- syz.8.330/6635 is trying to acquire lock: ffff88807a2960b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1 but task is already holding lock: ffff88807a2960b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&tree->tree_lock/1); lock(&tree->tree_lock/1); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.8.330/6635: #0: ffff88804d260460 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev fs/read_write.c:927 [inline] #0: ffff88804d260460 (sb_writers#13){.+.+}-{0:0}, at: do_pwritev+0x229/0x3a0 fs/read_write.c:1025 #1: ffff88807dd34a28 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88807dd34a28 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: generic_file_write_iter+0x7e/0x1b0 mm/filemap.c:3941 #2: ffff88807dd34878 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x13f0 fs/hfs/extent.c:397 #3: ffff88807a2960b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1 #4: ffff88807dd33b78 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x13f0 fs/hfs/extent.c:397 stack backtrace: CPU: 1 PID: 6635 Comm: syz.8.330 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 __lock_acquire+0x1236/0x7d10 kernel/locking/lockdep.c:-1 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 hfs_find_init+0x15b/0x1d0 fs/hfs/bfind.c:-1 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x35d/0x13f0 fs/hfs/extent.c:401 hfs_bmap_reserve+0x103/0x420 fs/hfs/btree.c:231 __hfs_ext_write_extent+0x1fa/0x470 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6b/0x9b0 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x39c/0x13f0 fs/hfs/extent.c:401 hfs_get_block+0x40f/0xc50 fs/hfs/extent.c:353 __block_write_begin_int+0x565/0x15d0 fs/buffer.c:2012 __block_write_begin fs/buffer.c:2062 [inline] block_write_begin fs/buffer.c:2122 [inline] cont_write_begin+0x598/0x7b0 fs/buffer.c:2471 hfs_write_begin+0x92/0xe0 fs/hfs/inode.c:59 cont_expand_zero fs/buffer.c:2398 [inline] cont_write_begin+0x263/0x7b0 fs/buffer.c:2461 hfs_write_begin+0x92/0xe0 fs/hfs/inode.c:59 generic_perform_write+0x2b6/0x550 mm/filemap.c:3785 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944 do_iter_readv_writev+0x47e/0x5f0 fs/read_write.c:-1 do_iter_write+0x205/0x7b0 fs/read_write.c:855 vfs_writev fs/read_write.c:928 [inline] do_pwritev+0x240/0x3a0 fs/read_write.c:1025 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7febc0852819 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:00007febbeaac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000148 RAX: ffffffffffffffda RBX: 00007febc0acbfa0 RCX: 00007febc0852819 RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000004 RBP: 00007febc08e8c91 R08: 000000000000000c R09: 0000000000000004 R10: 0000000000800fff R11: 0000000000000246 R12: 0000000000000000 R13: 00007febc0acc038 R14: 00007febc0acbfa0 R15: 00007fffe9d10558