replace a read-only file cause the parent folder keep being occupied

[NatsuKageX]

the reproduce methods:
1.run mirror sample.
2.create a new txt file in dokan disk.
3.set the txt file read-only attribute.
4.copy a new txt file with same filename to dokan disk and try overwrite the old one.
5.rename the other files below the same dokan parent folder of the txt file, it will always return status_sharing_violation

from the debug mode, I saw the parent folder was opened by dokan.dll and does not close it no more. I can fix it by return ACCESS_DENIED on function MirrorCreateFile when try to overwrite a read-only file or close the opened handle in function DispatchCreate, but I'm not sure which way is better.

[Liryna]

When the create to delete a file fails the mirror fake a create on the parent to check whether it gives the permission to remove children (the .txt file). The problem here is that the filesystem handle in the request context is the parent and not the file targeted by the request. Therefore sub request that expects to target a file fails,

This logic should be removed. We should let the filesystem implementation do the parent check internally.

dokany/dokan/create.c

Lines 250 to 298 in 726bf60

	if (STATUS_ACCESS_DENIED == status &&
	IoEvent->DokanInstance->DokanOperations->ZwCreateFile &&
	(IoEvent->EventContext->Operation.Create.SecurityContext.DesiredAccess &
	DELETE)) {
	DbgPrint("Delete failed, ask parent folder if we have the right\n");
	// strip the last section of the file path
	WCHAR *lastP = NULL;
	for (WCHAR *p = fileName; *p; p++) {
	if ((*p == L'\\' || *p == L'/') && p[1])
	lastP = p;
	}
	if (lastP) {
	*lastP = 0;
	}
	SetIOSecurityContext(IoEvent->EventContext, &ioSecurityContext);
	ACCESS_MASK newDesiredAccess =
	(MAXIMUM_ALLOWED & ioSecurityContext.DesiredAccess)
	? (FILE_DELETE_CHILD | FILE_LIST_DIRECTORY)
	: (((DELETE & ioSecurityContext.DesiredAccess) ? FILE_DELETE_CHILD
	: 0) |
	((FILE_READ_ATTRIBUTES & ioSecurityContext.DesiredAccess)
	? FILE_LIST_DIRECTORY
	: 0));
	options |= FILE_OPEN_FOR_BACKUP_INTENT; //Enable open directory
	options &= ~FILE_NON_DIRECTORY_FILE; //Remove non dir flag
	status = IoEvent->DokanInstance->DokanOperations->ZwCreateFile(
	fileName, &ioSecurityContext, newDesiredAccess,
	IoEvent->EventContext->Operation.Create.FileAttributes,
	IoEvent->EventContext->Operation.Create.ShareAccess, disposition,
	options, &IoEvent->DokanFileInfo);
	if (status == STATUS_SUCCESS) {
	DbgPrint("Parent give us the right to delete\n");
	IoEvent->EventResult->Status = STATUS_SUCCESS;
	IoEvent->EventResult->Operation.Create.Information = FILE_OPENED;
	} else {
	DbgPrint("Parent CreateFile failed status = %lx\n", status);
	PushFileOpenInfo(IoEvent->DokanOpenInfo);
	IoEvent->DokanOpenInfo = NULL;
	}
	} else {
	PushFileOpenInfo(IoEvent->DokanOpenInfo);
	IoEvent->DokanOpenInfo = NULL;
	}
	} else {

[NatsuKageX]

I tried remove this logic from DispatchCreate and it works. Thanks!

[Liryna]

Great! I am keeping this open so we can do this at head too

[NatsuKageX]

Great! I am keeping this open so we can do this at head too

Thanks! And I have also found the reproduce methods of issue #1293. Hope to troubleshoot it soon.