[FASTFAT] Don't add an extra \, when renaming a file at root.

This fixes failures to rename a file where destination is
the root of a FAT volume.

CORE-10503

diff --git a/drivers/filesystems/fastfat/finfo.c b/drivers/filesystems/fastfat/finfo.c
index 517d738..a19c21d 100644 (file)
--- a/drivers/filesystems/fastfat/finfo.c
+++ b/drivers/filesystems/fastfat/finfo.c
@@ -787,8 +787,12 @@ VfatSetRenameInformation(
         }
 
         RtlCopyUnicodeString(&NewName, &((PVFATFCB)TargetFileObject->FsContext)->PathNameU);
         }
 
         RtlCopyUnicodeString(&NewName, &((PVFATFCB)TargetFileObject->FsContext)->PathNameU);

-        NewName.Buffer[NewName.Length / sizeof(WCHAR)] = L'\\';
-        NewName.Length += sizeof(WCHAR);
+        /* If \, it's already backslash terminated, don't add it */
+        if (!vfatFCBIsRoot(TargetFileObject->FsContext))
+        {
+            NewName.Buffer[NewName.Length / sizeof(WCHAR)] = L'\\';
+            NewName.Length += sizeof(WCHAR);
+        }

         RtlAppendUnicodeStringToString(&NewName, &TargetFileObject->FileName);
     }
 
         RtlAppendUnicodeStringToString(&NewName, &TargetFileObject->FileName);
     }