[PATCH v2 2/6] Fix Length calculation in PdoQueryId

[Owen Smith <owen.smith@xxxxxxxxx>]

Decrease Length by the string length of the current ID before moving
the Buffer value to the end of the current ID. Without this, Length
is not decreased, leading to potential issues with the next call to
RtlStringCbPrintfW.
Note: the second chunk it to maintain consistent ordering of operations
for clarity, and has no functional change.

Signed-off-by: Owen Smith <owen.smith@xxxxxxxxx>
---
 src/xenbus/pdo.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/xenbus/pdo.c b/src/xenbus/pdo.c
index 5e6fff3..663dd3b 100644
--- a/src/xenbus/pdo.c
+++ b/src/xenbus/pdo.c
@@ -1456,11 +1456,11 @@ PdoQueryId(
                                         Revision->Number);
             ASSERT(NT_SUCCESS(status));
 
-            Buffer += wcslen(Buffer);
             Length -= (ULONG)(wcslen(Buffer) * sizeof (WCHAR));
+            Buffer += wcslen(Buffer);
 
-            Buffer++;
             Length -= sizeof (WCHAR);
+            Buffer++;
 
             --Index;
         }
-- 
2.41.0.windows.3