- Implement the ThreadDescriptorTableEntry case for NtQueryInformationThread. This is required for the GetThreadSelectorEntry routine used by user mode debuggers.

- #if out some x86-only LDT code from PS and move it to psldt.c.

svn path=/trunk/; revision=43827

reactos/dll/win32/kernel32/thread/thread.c

@@ -651,7 +651,8 @@ SetThreadPriorityBoost(IN HANDLE hThread,
 /*
  * @implemented
  */
-BOOL WINAPI
+BOOL
+WINAPI
 GetThreadSelectorEntry(IN HANDLE hThread,
                        IN DWORD dwSelector,
                        OUT LPLDT_ENTRY lpSelectorEntry)
@@ -659,18 +660,21 @@ GetThreadSelectorEntry(IN HANDLE hThread,
     DESCRIPTOR_TABLE_ENTRY DescriptionTableEntry;
     NTSTATUS Status;
 
+    /* Set the selector and do the query */
     DescriptionTableEntry.Selector = dwSelector;
     Status = NtQueryInformationThread(hThread,
                                       ThreadDescriptorTableEntry,
                                       &DescriptionTableEntry,
                                       sizeof(DESCRIPTOR_TABLE_ENTRY),
                                       NULL);
-  if(!NT_SUCCESS(Status))
+    if (!NT_SUCCESS(Status))
     {
+        /* Fail */
         SetLastErrorByStatus(Status);
         return FALSE;
     }
 
+    /* Success, return the selector */
     *lpSelectorEntry = DescriptionTableEntry.Descriptor;
     return TRUE;
 }

reactos/include/ndk/i386/ketypes.h

@@ -66,6 +66,11 @@ Author:
 #define KGDT_DF_TSS             0x50
 #define KGDT_NMI_TSS            0x58
 
+//
+// Define the number of GDTs that can be queried by user mode
+//
+#define KGDT_NUMBER             10
+
 //
 // CR4
 //

reactos/ntoskrnl/include/internal/i386/ke.h

@@ -88,6 +88,14 @@ KiThreadStartup(PKSYSTEM_ROUTINE SystemRoutine,
                 KTRAP_FRAME TrapFrame);
 #endif
 
+NTSTATUS
+NTAPI
+Ke386GetGdtEntryThread(
+    IN PKTHREAD Thread,
+    IN ULONG Offset,
+    IN PKGDTENTRY Descriptor
+);
+
 #endif
 #endif /* __NTOSKRNL_INCLUDE_INTERNAL_I386_KE_H */
 

reactos/ntoskrnl/include/internal/ps.h

@@ -300,8 +300,9 @@ PspDestroyQuotaBlock(
     IN PEPROCESS Process
 );
 
+#if defined(_X86_)
 //
-// VDM Support
+// VDM and LDT Support
 //
 NTSTATUS
 NTAPI
@@ -315,6 +316,16 @@ PspDeleteVdmObjects(
     IN PEPROCESS Process
 );
 
+NTSTATUS
+NTAPI
+PspQueryDescriptorThread(
+    IN PETHREAD Thread,
+    IN PVOID ThreadInformation,
+    IN ULONG ThreadInformationLength,
+    OUT PULONG ReturnLength OPTIONAL
+);
+#endif
+
 //
 // Job Routines
 //

reactos/ntoskrnl/ke/i386/ldt.c

@@ -5,6 +5,7 @@
  * PURPOSE:         LDT managment
  *
  * PROGRAMMERS:     David Welch (welch@cwcom.net)
+ *                  Stefan Ginsberg (stefan.ginsberg@reactos.org)
  */
 
 /* INCLUDES *****************************************************************/
@@ -20,6 +21,55 @@ static KSPIN_LOCK GdtLock;
 
 /* FUNCTIONS *****************************************************************/
 
+NTSTATUS
+NTAPI
+Ke386GetGdtEntryThread(IN PKTHREAD Thread,
+                       IN ULONG Offset,
+                       IN PKGDTENTRY Descriptor)
+{
+    /* Make sure the offset is inside the allowed range */
+    if (!((Offset) < (KGDT_NUMBER * sizeof(KGDTENTRY))))
+    {
+        /* It isn't, fail */
+        return STATUS_ACCESS_VIOLATION;
+    }
+
+    /* Check if this is the LDT selector */
+    if (Offset == KGDT_LDT)
+    {
+        /* Get it from the thread's process */
+        RtlCopyMemory(Descriptor,
+                      &Thread->Process->LdtDescriptor,
+                      sizeof(KGDTENTRY));
+    }
+    else
+    {
+        /* Get the descriptor entry from the GDT */
+        RtlCopyMemory(Descriptor,
+                      (PCHAR)((PKIPCR)KeGetPcr()->GDT) + Offset,
+                      sizeof(KGDTENTRY));
+
+        /* Check if this is the TEB selector */
+        if (Offset == KGDT_R3_TEB)
+        {
+            /*
+             * Make sure we set the correct base for this thread. This is per
+             * process and is set in the GDT on context switch, so it might not
+             * be correct for the thread specified.
+             */
+            Descriptor->BaseLow =
+                (USHORT)((ULONG_PTR)(Thread->Teb) & 0xFFFF);
+            Descriptor->HighWord.Bytes.BaseMid =
+                (UCHAR)((ULONG_PTR)(Thread->Teb) >> 16);
+            Descriptor->HighWord.Bytes.BaseHi =
+                (UCHAR)((ULONG_PTR)(Thread->Teb) >> 24);
+        }
+    }
+
+    /* Success */
+    return STATUS_SUCCESS;
+}
+
 VOID
 KeSetBaseGdtSelector(ULONG Entry,
 		     PVOID Base)

reactos/ntoskrnl/ntoskrnl-generic.rbuild

@@ -444,6 +444,7 @@
 		<if property="ARCH" value="i386">
 			<directory name="i386">
 				<file>psctx.c</file>
+				<file>psldt.c</file>
 			</directory>
 		</if>
 		<if property="ARCH" value="arm">

reactos/ntoskrnl/ps/i386/psldt.c

@@ -0,0 +1,105 @@
+/*
+ * PROJECT:         ReactOS Kernel
+ * LICENSE:         GPL - See COPYING in the top level directory
+ * FILE:            ntoskrnl/ps/i386/psldt.c
+ * PURPOSE:         LDT support for x86
+ * PROGRAMMERS:     Stefan Ginsberg (stefan.ginsberg@reactos.org)
+ */
+
+/* INCLUDES ******************************************************************/
+
+#include <ntoskrnl.h>
+#define NDEBUG
+#include <debug.h>
+
+/* FUNCTIONS *****************************************************************/
+
+NTSTATUS
+NTAPI
+PspDeleteLdt(PEPROCESS Process)
+{
+    /* FIXME */
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS
+NTAPI
+PspDeleteVdmObjects(PEPROCESS Process)
+{
+    /* FIXME */
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS
+NTAPI
+PspQueryDescriptorThread(IN PETHREAD Thread,
+                         IN PVOID ThreadInformation,
+                         IN ULONG ThreadInformationLength,
+                         OUT PULONG ReturnLength OPTIONAL)
+{
+    DESCRIPTOR_TABLE_ENTRY DescriptorEntry;
+    LDT_ENTRY Descriptor;
+    NTSTATUS Status;
+    PAGED_CODE();
+
+    /* Verify the size */
+    if (ThreadInformationLength != sizeof(DESCRIPTOR_TABLE_ENTRY))
+    {
+        /* Fail */
+        return STATUS_INFO_LENGTH_MISMATCH;
+    }
+
+    /* Enter SEH for the copy */
+    _SEH2_TRY
+    {
+        /* Get the descriptor */
+        RtlCopyMemory(&DescriptorEntry,
+                      ThreadInformation,
+                      sizeof(DESCRIPTOR_TABLE_ENTRY));
+    }
+    _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
+    {
+        /* Return the exception code */
+        _SEH2_YIELD(return _SEH2_GetExceptionCode());
+    }
+    _SEH2_END;
+
+    /* Check if this is a GDT selector */
+    if (!(DescriptorEntry.Selector & 0x4))
+    {
+        /* Get the GDT entry */
+        Status = Ke386GetGdtEntryThread(&Thread->Tcb,
+                                        DescriptorEntry.Selector & 0xFFFFFFF8,
+                                        (PKGDTENTRY)&Descriptor);
+        if (!NT_SUCCESS(Status)) return Status;
+
+        /* Enter SEH for the copy */
+        _SEH2_TRY
+        {
+            /* Copy the GDT entry to caller */
+            RtlCopyMemory(&((PDESCRIPTOR_TABLE_ENTRY)ThreadInformation)->
+                          Descriptor,
+                          &Descriptor,
+                          sizeof(LDT_ENTRY));
+            if (ReturnLength) *ReturnLength = sizeof(LDT_ENTRY);
+        }
+        _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
+        {
+            /* Return the exception code */
+            _SEH2_YIELD(return _SEH2_GetExceptionCode());
+        }
+        _SEH2_END;
+
+        /* Success */
+        Status = STATUS_SUCCESS;
+    }
+    else
+    {
+        /* This is only supported for VDM, which we don't implement */
+        ASSERT(Thread->ThreadsProcess->LdtInformation == NULL);
+        Status = STATUS_NO_LDT;
+    }
+
+    /* Return status to caller */
+    return Status;
+}

reactos/ntoskrnl/ps/kill.c

@@ -270,9 +270,11 @@ PspDeleteProcess(IN PVOID ObjectBody)
         Process->SectionObject = NULL;
     }
 
-    /* Clean LDT and VDM_OBJECTS */
+#if defined(_X86_)
+    /* Clean Ldt and Vdm objects */
     PspDeleteLdt(Process);
     PspDeleteVdmObjects(Process);
+#endif
 
     /* Delete the Object Table */
     if (Process->ObjectTable)

reactos/ntoskrnl/ps/process.c

@@ -70,22 +70,6 @@ KPRIORITY PspPriorityTable[PROCESS_PRIORITY_CLASS_ABOVE_NORMAL + 1] =
 
 /* PRIVATE FUNCTIONS *********************************************************/
 
-NTSTATUS
-NTAPI
-PspDeleteLdt(PEPROCESS Process)
-{
-    /* FIXME */
-    return STATUS_SUCCESS;
-}
-
-NTSTATUS
-NTAPI
-PspDeleteVdmObjects(PEPROCESS Process)
-{
-    /* FIXME */
-    return STATUS_SUCCESS;
-}
-
 PETHREAD
 NTAPI
 PsGetNextProcessThread(IN PEPROCESS Process,

reactos/ntoskrnl/ps/query.c

@@ -1819,9 +1819,19 @@ NtQueryInformationThread(IN HANDLE ThreadHandle,
             KeLowerIrql(OldIrql);
             break;
 
+        /* LDT and GDT information */
         case ThreadDescriptorTableEntry:
-            DPRINT1("NtQueryInformationThread(): case ThreadDescriptorTableEntry not implemented!\n");
+
+#if defined(_X86_)
+            /* Call the worker routine */
+            Status = PspQueryDescriptorThread(Thread,
+                                              ThreadInformation,
+                                              ThreadInformationLength,
+                                              ReturnLength);
+#else
+            /* Only implemented on x86 */
             Status = STATUS_NOT_IMPLEMENTED;
+#endif
             break;
 
         case ThreadPriorityBoost: