From 4e6d587275cc8d97f1fcf3ca650d9b3fb32c633f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fran=C3=A7ois=20Colas?= <francois.colas@ledger.fr>
Date: Wed, 27 May 2020 14:57:05 +0200
Subject: [PATCH] Fix incorrect lenght of command INS_PREFIX_HASH

buffer_send[4] (LC) is an unsigned char, len should not
exceed 254 (255 - 1 for the option).
---
 src/device/device_ledger.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/device/device_ledger.cpp b/src/device/device_ledger.cpp
index 222a84d3f..0783b00b0 100644
--- a/src/device/device_ledger.cpp
+++ b/src/device/device_ledger.cpp
@@ -1468,8 +1468,8 @@ namespace hw {
         offset = set_command_header(INS_PREFIX_HASH,2,cnt);      
         len = pref_length - pref_offset;
         //options
-        if (len > (BUFFER_SEND_SIZE-7)) {
-          len = BUFFER_SEND_SIZE-7;
+        if (len > (BUFFER_SEND_SIZE-offset-3)) {
+          len = BUFFER_SEND_SIZE-offset-3;
           this->buffer_send[offset] = 0x80;
         } else {
           this->buffer_send[offset] = 0x00;