don't memcpy to ourselves (It is undefined)

bwalex · Jun 21, 2012 · 4322ebf · 4322ebf
1 parent aa7ee2e
commit 4322ebf
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/crypto-gcrypt.c b/crypto-gcrypt.c
@@ -171,7 +171,10 @@ syscrypt(struct tc_crypto_algo *cipher, unsigned char *key, size_t klen, unsigne
 		return EINVAL;
 	}
 
-	memcpy(out, in, len);
+	/* When chaining ciphers, we reuse the input buffer as the output buffer */
+	if (out != in)
+		memcpy(out, in, len);
+
 	if (do_encrypt)
 		err = xts_encrypt(ctx, out, len, iv);
 	else