From 323c91fad80c2cf02acdd42ed8a009153ed01b49 Mon Sep 17 00:00:00 2001
From: Joseph Lee <joseph@zeronsoftn.com>
Date: Fri, 10 Jan 2025 10:40:29 +0900
Subject: [PATCH] fix: use null-terminator if incorrect length

---
 efi/efivario/context_windows.go | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/efi/efivario/context_windows.go b/efi/efivario/context_windows.go
index 93807c3..c7db299 100644
--- a/efi/efivario/context_windows.go
+++ b/efi/efivario/context_windows.go
@@ -46,9 +46,24 @@ func (e *bufferVarEntry) ReadFrom(r io.Reader) (n int64, err error) {
 		return
 	}
 
-	e.Name = make([]byte, e.Length-20)
-	if _, err = io.ReadFull(fr, e.Name); err != nil {
-		return
+	if e.Length < 20 {
+		var nameBuffer []byte
+		for {
+			var u16char [2]byte
+			if err = fr.ReadFields(u16char[:]); err != nil {
+				return
+			}
+			nameBuffer = append(nameBuffer, u16char[0], u16char[1])
+			if u16char[0] == 0 && u16char[1] == 0 {
+				break
+			}
+		}
+		e.Name = nameBuffer
+	} else {
+		e.Name = make([]byte, e.Length-20)
+		if _, err = io.ReadFull(fr, e.Name); err != nil {
+			return
+		}
 	}
 
 	return