Step 1: 
Patch 1:

```diff
-	if (!buffer_within_range(pbOrderHdr, 1, pbEnd))
+	if (runLength == 0 && !buffer_within_range(pbOrderHdr, 1, pbEnd))
```

Patch 2:

```diff
-	if (!buffer_within_range(pbOrderHdr, 1, pbEnd))
+	if (runLength == 0 || !buffer_within_range(pbOrderHdr, 1, pbEnd))
```

Patch 3:

```diff
-	if (!buffer_within_range(pbOrderHdr, 1, pbEnd))
+	if (runLength == 0 && !buffer_within_range(pbOrderHdr, 2, pbEnd))
```

Patch 4:

```diff
-	if (!buffer_within_range(pbOrderHdr, 1, pbEnd))
+	if (runLength == 0 || !buffer_within_range(pbOrderHdr, 2, pbEnd))
```

Patch 5:

```diff
-	if (!buffer_within_range(pbOrderHdr, 1, pbEnd))
+	if (runLength == 0 && !buffer_within_range(pbOrderHdr + 1, 2, pbEnd))
```

Note: The patches are based on the assumption that `runLength` is only valid if it is not zero and `pbOrderHdr` must be within range when `runLength` is not zero.