Unzipping and renaming 3 times results in a file length of 0

[xuyouqiao2005]

Bug Report

Unzipping and renaming 3 times results in a file length of 0

How to Reproduce

srcFile: xxx.7z
unzipping it, we can got tree:
xxx/
├─1.txt
├─2.txt
├─3.txt

1.txt/2.txt/3.txt is not empty

start memfs cmd: -i -n 1024 -m P: -s 848297984 -t 10000 -f
step1: copy xxx.7z to P:\xxx.7z
step2: using 7z to unzipping it to xxx/

step3: rename xxx/ to xxx1/
step4: using 7z to unzipping it to xxx/

step5: rename xxx/ to xxx2/
step6: using 7z to unzipping it to xxx/

use cmd: ls
got:

Mode LastWriteTime Length Name

---

-a---- 2023/6/29 10:10 0 1.txt
-a---- 2023/6/29 10:10 0 2.txt
-a---- 2023/6/29 9:57 9 3.txt

Behaviors

we find 1.txt/2.txt is changed to 0 bytes
if you repeat step3/step4 again, you counld find other errors, such as cannot not access xxx2/. two xxx/ directorys

Environment

• OS version and build: 10.0.19045
• WinFsp version and build: 20230529T013725Z

[xuyouqiao2005]

i dont sure that problem is caused in function FspFsvolCreateComplete, you may changed the FileDesc fileNode. if xxx/ directory has more files, such steps resule memfs wild pointer crash.

    ....
    if (FileNode != OpenedFileNode)
    {
        FspFileNodeDereference(FileNode);
        FileDesc->FileNode = FileNode = OpenedFileNode;
    }
    ...