[NTOS] On DBG builds, fill pool allocations with 0xCD and freed pool with 0xDD

This matches what the MSVC runtime does with heap allocations on debug builds.

ntoskrnl/mm/ARM3/expool.c

@@ -1859,6 +1859,7 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
     ULONG OriginalType;
     PKPRCB Prcb = KeGetCurrentPrcb();
     PGENERAL_LOOKASIDE LookasideList;
+    PVOID Allocation;
 
     //
     // Some sanity checks
@@ -1898,10 +1899,13 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
             if (MmUseSpecialPool(NumberOfBytes, Tag))
             {
                 //
-                // Try to allocate using special pool
+                // Try to allocate using special pool (initialized with random byte)
                 //
-                Entry = MmAllocateSpecialPool(NumberOfBytes, Tag, PoolType, 2);
+                Allocation = MmAllocateSpecialPool(NumberOfBytes, Tag, PoolType, 2);
-                if (Entry) return Entry;
+                if (Allocation != NULL)
+                {
+                    return Allocation;
+                }
             }
         }
     }
@@ -1922,8 +1926,8 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
         //
         // Allocate pages for it
         //
-        Entry = MiAllocatePoolPages(OriginalType, NumberOfBytes);
+        Allocation = MiAllocatePoolPages(OriginalType, NumberOfBytes);
-        if (!Entry)
+        if (Allocation == NULL)
         {
 #if DBG
             //
@@ -1995,7 +1999,7 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
         // Add a tag for the big page allocation and switch to the generic "BIG"
         // tag if we failed to do so, then insert a tracker for this alloation.
         //
-        if (!ExpAddTagForBigPages(Entry,
+        if (!ExpAddTagForBigPages(Allocation,
                                   Tag,
                                   (ULONG)BYTES_TO_PAGES(NumberOfBytes),
                                   OriginalType))
@@ -2003,7 +2007,7 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
             Tag = ' GIB';
         }
         ExpInsertPoolTracker(Tag, ROUND_TO_PAGES(NumberOfBytes), OriginalType);
-        return Entry;
+        return Allocation;
     }
 
     //
@@ -2073,7 +2077,11 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
             Entry->PoolTag = Tag;
             (POOL_FREE_BLOCK(Entry))->Flink = NULL;
             (POOL_FREE_BLOCK(Entry))->Blink = NULL;
-            return POOL_FREE_BLOCK(Entry);
+            Allocation = POOL_FREE_BLOCK(Entry);
+#if DBG
+            RtlFillMemory(Allocation, NumberOfBytes, 0xCD);
+#endif
+            return Allocation;
         }
     }
 
@@ -2257,7 +2265,11 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
             Entry->PoolTag = Tag;
             (POOL_FREE_BLOCK(Entry))->Flink = NULL;
             (POOL_FREE_BLOCK(Entry))->Blink = NULL;
-            return POOL_FREE_BLOCK(Entry);
+            Allocation = POOL_FREE_BLOCK(Entry);
+#if DBG
+            RtlFillMemory(Allocation, NumberOfBytes, 0xCD);
+#endif
+            return Allocation;
         }
     } while (++ListHead != &PoolDesc->ListHeads[POOL_LISTS_PER_PAGE]);
 
@@ -2400,7 +2412,9 @@ ExAllocatePoolWithTag(IN POOL_TYPE PoolType,
     //
     ExpCheckPoolBlocks(Entry);
     Entry->PoolTag = Tag;
-    return POOL_FREE_BLOCK(Entry);
+    Allocation = POOL_FREE_BLOCK(Entry);
+
+    return Allocation;
 }
 
 /*
@@ -2544,6 +2558,10 @@ ExFreePoolWithTag(IN PVOID P,
             Tag &= ~PROTECTED_POOL;
         }
 
+#if DBG
+        RtlFillMemory(P, PageCount * PAGE_SIZE, 0xDD);
+#endif
+
         //
         // Check block tag
         //
@@ -2669,6 +2687,10 @@ ExFreePoolWithTag(IN PVOID P,
         }
     }
 
+#if DBG
+    RtlFillMemory(P, BlockSize * POOL_BLOCK_SIZE - sizeof(*Entry), 0xDD);
+#endif
+
     //
     // Is this allocation small enough to have come from a lookaside list?
     //

ntoskrnl/mm/ARM3/pool.c

@@ -665,6 +665,9 @@ MiAllocatePoolPages(IN POOL_TYPE PoolType,
         //
         // Return the allocation address to the caller
         //
+#if DBG
+        RtlFillMemory(BaseVa, ROUND_TO_PAGES(SizeInBytes), 0xCD);
+#endif
         return BaseVa;
     }
 
@@ -674,7 +677,13 @@ MiAllocatePoolPages(IN POOL_TYPE PoolType,
     if ((SizeInPages == 1) && (ExQueryDepthSList(&MiNonPagedPoolSListHead)))
     {
         BaseVa = InterlockedPopEntrySList(&MiNonPagedPoolSListHead);
-        if (BaseVa) return BaseVa;
+        if (BaseVa)
+        {
+#if DBG
+            RtlFillMemory(BaseVa, ROUND_TO_PAGES(SizeInBytes), 0xCD);
+#endif
+            return BaseVa;
+        }
     }
 
     //
@@ -802,6 +811,9 @@ MiAllocatePoolPages(IN POOL_TYPE PoolType,
                 // Release the nonpaged pool lock, and return the allocation
                 //
                 KeReleaseQueuedSpinLock(LockQueueMmNonPagedPoolLock, OldIrql);
+#if DBG
+                RtlFillMemory(BaseVa, ROUND_TO_PAGES(SizeInBytes), 0xCD);
+#endif
                 return BaseVa;
             }
 
@@ -897,7 +909,11 @@ MiAllocatePoolPages(IN POOL_TYPE PoolType,
     //
     // Return the address
     //
-    return MiPteToAddress(StartPte);
+    BaseVa = MiPteToAddress(StartPte);
+#if DBG
+            RtlFillMemory(BaseVa, ROUND_TO_PAGES(SizeInBytes), 0xCD);
+#endif
+    return BaseVa;
 }
 
 ULONG