审计修复第五轮: 二次审计发现的注释修正

- hash.go: 更新过时注释（不再引用已消除的 global sumBuffer）
- hash.go: 拼写修复 hashLenthRange → hashLengthRange

Author: love

hash.go

@@ -111,8 +111,8 @@ func addGarbleToHash(inputHash []byte) [sha256.Size]byte {
 	// separate the env vars and flags, to reduce the chances of collisions.
 	fmt.Fprintf(hasher, " GOGARBLE=%s", sharedCache.GOGARBLE)
 	appendFlags(hasher, true)
-	// addGarbleToHash returns the sum buffer, so we need a new copy.
-	// Otherwise the next use of the global sumBuffer would conflict.
+	// addGarbleToHash returns the sum buffer, so we use a local copy
+	// to avoid any potential conflicts across callers.
 	var sumBuffer [sha256.Size]byte
 	hasher.Sum(sumBuffer[:0])
 	return sumBuffer
@@ -332,7 +332,7 @@ func hashWithCustomSalt(salt []byte, name string) string {
 	// The byte after neededSumBytes is never used as part of the name,
 	// but it is still deterministic and hard to predict,
 	// so it provides us with useful randomness between 0 and 255.
-	// We want the number to be between 0 and hashLenthRange-1 as well,
+	// We want the number to be between 0 and hashLengthRange-1 as well,
 	// so we use a remainder operation.
 	hashLengthRandomness := sum[neededSumBytes] % ((maxHashLength - minHashLength) + 1)
 	hashLength := minHashLength + hashLengthRandomness