============================================ WARNING: possible recursive locking detected 6.1.87-syzkaller #0 Not tainted -------------------------------------------- syz-executor.0/3663 is trying to acquire lock: ffff8880577cc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x16a/0x1e0 but task is already holding lock: ffff8880577cc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x16a/0x1e0 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 6 locks held by syz-executor.0/3663: #0: ffff8880259399e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ba/0x360 fs/file.c:1062 #1: ffff8880577ca460 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x269/0xba0 fs/read_write.c:580 #2: ffff8880577d9628 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff8880577d9628 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: generic_file_write_iter+0x7f/0x310 mm/filemap.c:3974 #3: ffff8880577d9478 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x1440 fs/hfs/extent.c:397 #4: ffff8880577cc0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x16a/0x1e0 #5: ffff8880577d80f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x1440 fs/hfs/extent.c:397 stack backtrace: CPU: 0 PID: 3663 Comm: syz-executor.0 Not tainted 6.1.87-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2983 [inline] check_deadlock kernel/locking/lockdep.c:3026 [inline] validate_chain+0x4711/0x5950 kernel/locking/lockdep.c:3812 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747 hfs_find_init+0x16a/0x1e0 hfs_ext_read_extent fs/hfs/extent.c:200 [inline] hfs_extend_file+0x317/0x1440 fs/hfs/extent.c:401 hfs_bmap_reserve+0xd5/0x3f0 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x22e/0x4f0 fs/hfs/extent.c:121 __hfs_ext_cache_extent+0x6a/0x990 fs/hfs/extent.c:174 hfs_ext_read_extent fs/hfs/extent.c:202 [inline] hfs_extend_file+0x340/0x1440 fs/hfs/extent.c:401 hfs_get_block+0x3e0/0xb60 fs/hfs/extent.c:353 __block_write_begin_int+0x544/0x1a30 fs/buffer.c:1991 __block_write_begin fs/buffer.c:2041 [inline] block_write_begin+0x98/0x1f0 fs/buffer.c:2102 cont_write_begin+0x63f/0x880 fs/buffer.c:2456 hfs_write_begin+0x86/0xd0 fs/hfs/inode.c:58 generic_perform_write+0x2fc/0x5e0 mm/filemap.c:3817 __generic_file_write_iter+0x176/0x400 mm/filemap.c:3945 generic_file_write_iter+0xab/0x310 mm/filemap.c:3977 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7ae/0xba0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f015847dea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f015914f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f01585ac120 RCX: 00007f015847dea9 RDX: 000000006db6e559 RSI: 0000000020000040 RDI: 000000000000000a RBP: 00007f01584ca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f01585ac120 R15: 00007ffeba3d3d98