[ion] 17059: - Protect semaphore release with SEH, since it can cause an exception

- Protect semaphore release with SEH, since it can cause an exception
- Correct object type initializer
- Correct incorrect PreviousMode checks
- Correct MaximumCount and ReleaseCount checks since they can't be
negative either
- Harmonize formatting
Modified: trunk/reactos/ntoskrnl/ex/sem.c
  _____  

Modified: trunk/reactos/ntoskrnl/ex/sem.c
--- trunk/reactos/ntoskrnl/ex/sem.c	2005-08-05 06:54:15 UTC (rev
17058)
+++ trunk/reactos/ntoskrnl/ex/sem.c	2005-08-05 06:56:17 UTC (rev
17059)
@@ -2,9 +2,9 @@

  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS kernel
  * FILE:            ntoskrnl/ex/sem.c
- * PURPOSE:         Synchronization primitives
+ * PURPOSE:         Semaphore Implementation
  *
- * PROGRAMMERS:     Alex Ionescu (alex(a)relsoft.net)- Reformatting, bug
fixes.
+ * PROGRAMMERS:     Alex Ionescu (alex(a)relsoft.net)
  *                  David Welch (welch(a)mcmail.com)
  */
 
@@ -18,14 +18,16 @@
 
 POBJECT_TYPE ExSemaphoreObjectType;
 
-static GENERIC_MAPPING ExSemaphoreMapping = {
+static GENERIC_MAPPING ExSemaphoreMapping =
+{
     STANDARD_RIGHTS_READ    | SEMAPHORE_QUERY_STATE,
     STANDARD_RIGHTS_WRITE   | SEMAPHORE_MODIFY_STATE,
     STANDARD_RIGHTS_EXECUTE | SYNCHRONIZE | SEMAPHORE_QUERY_STATE,
-    SEMAPHORE_ALL_ACCESS};
+    SEMAPHORE_ALL_ACCESS
+};
 
-static const INFORMATION_CLASS_INFO ExSemaphoreInfoClass[] = {
-
+static const INFORMATION_CLASS_INFO ExSemaphoreInfoClass[] =
+{
      /* SemaphoreBasicInformation */
     ICI_SQ_SAME( sizeof(SEMAPHORE_BASIC_INFORMATION), sizeof(ULONG),
ICIF_QUERY ),
 };
@@ -47,8 +49,8 @@
     ObjectTypeInitializer.DefaultNonPagedPoolCharge =
sizeof(KSEMAPHORE);
     ObjectTypeInitializer.GenericMapping = ExSemaphoreMapping;
     ObjectTypeInitializer.PoolType = NonPagedPool;
+    ObjectTypeInitializer.InvalidAttributes = OBJ_OPENLINK;
     ObjectTypeInitializer.ValidAccessMask = SEMAPHORE_ALL_ACCESS;
-    ObjectTypeInitializer.UseDefaultObject = TRUE;
     ObpCreateTypeObject(&ObjectTypeInitializer, &Name,
&ExSemaphoreObjectType);
 }
 
@@ -67,29 +69,29 @@
     HANDLE hSemaphore;
     KPROCESSOR_MODE PreviousMode = ExGetPreviousMode();
     NTSTATUS Status = STATUS_SUCCESS;
-
     PAGED_CODE();
 
     /* Check Output Safety */
-    if(PreviousMode != KernelMode) {
-
-        _SEH_TRY {
-
+    if(PreviousMode != KernelMode)
+    {
+        _SEH_TRY 
+        {
             ProbeForWrite(SemaphoreHandle,
                           sizeof(HANDLE),
                           sizeof(ULONG));
-        } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
+        }
+        _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+        {
             Status = _SEH_GetExceptionCode();
+        }
+        _SEH_END;
 
-        } _SEH_END;
-
         if(!NT_SUCCESS(Status)) return Status;
     }
 
     /* Make sure the counts make sense */
-    if (!MaximumCount || InitialCount < 0 || InitialCount >
MaximumCount) {
-
+    if (MaximumCount <= 0 || InitialCount < 0 || InitialCount >
MaximumCount)
+    {
         DPRINT("Invalid Count Data!\n");
         return STATUS_INVALID_PARAMETER;
     }
@@ -106,8 +108,8 @@
                             (PVOID*)&Semaphore);
 
     /* Check for Success */
-    if (NT_SUCCESS(Status)) {
-
+    if (NT_SUCCESS(Status))
+    {
         /* Initialize it */
         KeInitializeSemaphore(Semaphore,
                               InitialCount,
@@ -123,17 +125,17 @@
         ObDereferenceObject(Semaphore);
 
         /* Check for success and return handle */
-        if(NT_SUCCESS(Status)) {
-
-            _SEH_TRY {
-
+        if(NT_SUCCESS(Status))
+        {
+            _SEH_TRY
+            {
                 *SemaphoreHandle = hSemaphore;
-
-            } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
+            }
+            _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+            {
                 Status = _SEH_GetExceptionCode();
-
-            } _SEH_END;
+            }
+            _SEH_END;
         }
     }
 
@@ -153,23 +155,23 @@
     HANDLE hSemaphore;
     KPROCESSOR_MODE PreviousMode = ExGetPreviousMode();
     NTSTATUS Status = STATUS_SUCCESS;
-
     PAGED_CODE();
 
     /* Check Output Safety */
-    if(PreviousMode == UserMode) {
-
-        _SEH_TRY {
-
+    if(PreviousMode != KernelMode)
+    {
+        _SEH_TRY
+        {
             ProbeForWrite(SemaphoreHandle,
                           sizeof(HANDLE),
                           sizeof(ULONG));
-        } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
+        }
+        _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+        {
             Status = _SEH_GetExceptionCode();
+        }
+        _SEH_END;
 
-        } _SEH_END;
-
         if(!NT_SUCCESS(Status)) return Status;
     }
 
@@ -183,16 +185,15 @@
                                 &hSemaphore);
 
     /* Check for success and return handle */
-    if(NT_SUCCESS(Status)) {
-
-        _SEH_TRY {
-
+    if(NT_SUCCESS(Status))
+    {
+        _SEH_TRY
+        {
             *SemaphoreHandle = hSemaphore;
-
-        } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
+        }
+        _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+        {
             Status = _SEH_GetExceptionCode();
-
         } _SEH_END;
     }
 
@@ -225,8 +226,8 @@
                                 ReturnLength,
                                 PreviousMode,
                                 &Status);
-    if(!NT_SUCCESS(Status)) {
-
+    if(!NT_SUCCESS(Status))
+    {
         /* Invalid buffers */
         DPRINT("NtQuerySemaphore() failed, Status: 0x%x\n", Status);
         return Status;
@@ -241,10 +242,10 @@
                                        NULL);
 
     /* Check for success */
-    if(NT_SUCCESS(Status)) {
-
-        _SEH_TRY {
-
+    if(NT_SUCCESS(Status))
+    {
+        _SEH_TRY
+        {
             PSEMAPHORE_BASIC_INFORMATION BasicInfo =
(PSEMAPHORE_BASIC_INFORMATION)SemaphoreInformation;
 
             /* Return the basic information */
@@ -254,10 +255,10 @@
             /* Return length */
             if(ReturnLength) *ReturnLength =
sizeof(SEMAPHORE_BASIC_INFORMATION);
 
-        } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
+        }
+        _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+        {
             Status = _SEH_GetExceptionCode();
-
         } _SEH_END;
 
         /* Dereference the Object */
@@ -284,25 +285,26 @@
     PAGED_CODE();
 
     /* Check buffer validity */
-    if(PreviousCount != NULL && PreviousMode == UserMode) {
-
-        _SEH_TRY {
-
+    if(PreviousCount && PreviousMode != KernelMode)
+    {
+        _SEH_TRY
+        {
             ProbeForWrite(PreviousCount,
                           sizeof(LONG),
                           sizeof(ULONG));
-         } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
+         }
+        _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+        {
             Status = _SEH_GetExceptionCode();
+        }
+        _SEH_END;
 
-        } _SEH_END;
-
         if(!NT_SUCCESS(Status)) return Status;
     }
 
     /* Make sure count makes sense */
-    if (!ReleaseCount) {
-
+    if (ReleaseCount <= 0)
+    {
         DPRINT("Invalid Release Count\n");
         return STATUS_INVALID_PARAMETER;
     }
@@ -316,28 +318,28 @@
                                        NULL);
 
     /* Check for success */
-    if (NT_SUCCESS(Status)) {
-
+    if (NT_SUCCESS(Status))
+    {
         /* Release the semaphore */
-        LONG PrevCount = KeReleaseSemaphore(Semaphore,
-                                            IO_NO_INCREMENT,
-                                            ReleaseCount,
-                                            FALSE);
-        ObDereferenceObject(Semaphore);
+        _SEH_TRY
+        {
+            LONG PrevCount = KeReleaseSemaphore(Semaphore,
+                                                IO_NO_INCREMENT,
+                                                ReleaseCount,
+                                                FALSE);
+            ObDereferenceObject(Semaphore);
 
-        /* Return it */
-        if(PreviousCount) {
-
-            _SEH_TRY {
-
+            /* Return the old count if requested */
+            if(PreviousCount)
+            {
                 *PreviousCount = PrevCount;
-
-            } _SEH_EXCEPT(_SEH_ExSystemExceptionFilter) {
-
-                Status = _SEH_GetExceptionCode();
-
-            } _SEH_END;
+            }
         }
+        _SEH_EXCEPT(_SEH_ExSystemExceptionFilter)
+        {
+            Status = _SEH_GetExceptionCode();
+        }
+        _SEH_END;
     }
 
     /* Return Status */