diff --git a/dlls/netapi32/wksta.c b/dlls/netapi32/wksta.c
index 1d22fc6f30..d89cd1a91a 100644
--- a/dlls/netapi32/wksta.c
+++ b/dlls/netapi32/wksta.c
@@ -445,7 +445,7 @@ NET_API_STATUS WINAPI NetpGetComputerName(LPWSTR *Buffer)
     if (GetComputerNameW(*Buffer,  &dwSize))
     {
         NetApiBufferReallocate(
-            *Buffer, dwSize * sizeof(WCHAR),
+            *Buffer, (dwSize + 1) * sizeof(WCHAR),
             (LPVOID *) Buffer);
         return NERR_Success;
     }