monitor: Fix zero-length field handling in print_hex_field

diff --git a/monitor/packet.c b/monitor/packet.c
index fae6161..9badfcd 100644 (file)
--- a/monitor/packet.c
+++ b/monitor/packet.c
@@ -1185,6 +1185,8 @@ static void print_hex_field(const char *label, const uint8_t *data,
        char str[len * 2 + 1];
        uint8_t i;
 
+       str[0] = '\0';
+
        for (i = 0; i < len; i++)
                sprintf(str + (i * 2), "%2.2x", data[i]);