And, you have, of course, confirmed that this piece of kernel code is wrong, and that DevMgr/Cfgapi/SetupApi are doing the right thing, right?
So if I was to reverse engineer ntoskrnl I wouldn't discover that it was actually doing the same thing as the un-"fixed" code, right?
Best regards,
Alex Ionescu
On Sun, Aug 14, 2011 at 10:44 AM,
<cgutman@svn.reactos.org> wrote:
Author: cgutman
Date: Sun Aug 14 14:44:34 2011
New Revision: 53232
URL: http://svn.reactos.org/svn/reactos?rev=53232&view=rev
Log:
[NTOSKRNL]
- Fix NULL termination of strings in IoGetDeviceProperty
- Fixes garbage displayed in the Enumerator field of the device manager property page
Modified:
trunk/reactos/ntoskrnl/io/pnpmgr/pnpmgr.c
Modified: trunk/reactos/ntoskrnl/io/pnpmgr/pnpmgr.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/io/pnpmgr/pnpmgr.c?rev=53232&r1=53231&r2=53232&view=diff
==============================================================================
--- trunk/reactos/ntoskrnl/io/pnpmgr/pnpmgr.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/io/pnpmgr/pnpmgr.c [iso-8859-1] Sun Aug 14 14:44:34 2011
@@ -3467,6 +3467,8 @@
NTSTATUS Status = STATUS_BUFFER_TOO_SMALL;
GUID BusTypeGuid;
POBJECT_NAME_INFORMATION ObjectNameInfo = NULL;
+ BOOLEAN NullTerminate = FALSE;
+
DPRINT("IoGetDeviceProperty(0x%p %d)\n", DeviceObject, DeviceProperty);
/* Assume failure */
@@ -3517,7 +3519,10 @@
/* Get the name from the path */
EnumeratorNameEnd = wcschr(DeviceInstanceName, OBJ_NAME_PATH_SEPARATOR);
ASSERT(EnumeratorNameEnd);
-
+
+ /* This string needs to be NULL-terminated */
+ NullTerminate = TRUE;
+
/* This is the format of the returned data */
PIP_RETURN_DATA((EnumeratorNameEnd - DeviceInstanceName) * sizeof(WCHAR),
DeviceInstanceName);
@@ -3567,7 +3572,10 @@
/* It's up to the caller to try again */
Status = STATUS_BUFFER_TOO_SMALL;
}
-
+
+ /* This string needs to be NULL-terminated */
+ NullTerminate = TRUE;
+
/* Return if successful */
if (NT_SUCCESS(Status)) PIP_RETURN_DATA(ObjectNameInfo->Name.Length,
ObjectNameInfo->Name.Buffer);
@@ -3633,15 +3641,14 @@
else if (NT_SUCCESS(Status))
{
/* We know up-front how much data to expect, check the caller's buffer */
- *ResultLength = ReturnLength;
- if (ReturnLength <= BufferLength)
+ *ResultLength = ReturnLength + (NullTerminate ? sizeof(UNICODE_NULL) : 0);
+ if (*ResultLength <= BufferLength)
{
/* Buffer is all good, copy the data */
RtlCopyMemory(PropertyBuffer, Data, ReturnLength);
- /* Check for properties that require a null-terminated string */
- if ((DeviceProperty == DevicePropertyEnumeratorName) ||
- (DeviceProperty == DevicePropertyPhysicalDeviceObjectName))
+ /* Check if we need to NULL-terminate the string */
+ if (NullTerminate)
{
/* Terminate the string */
((PWCHAR)PropertyBuffer)[ReturnLength / sizeof(WCHAR)] = UNICODE_NULL;