diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 5d4eef0..6c08b51 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -374,9 +374,9 @@
 }
 
 # Calculate the input & output maximum content lengths set in the config
-MAX_CONTENT_LEN=$(get_config_value_or_default "MBEDTLS_SSL_MAX_CONTENT_LEN")
-MAX_IN_LEN=$(get_config_value_or_default "MBEDTLS_SSL_IN_CONTENT_LEN")
-MAX_OUT_LEN=$(get_config_value_or_default "MBEDTLS_SSL_OUT_CONTENT_LEN")
+MAX_CONTENT_LEN=$( get_config_value_or_default "MBEDTLS_SSL_MAX_CONTENT_LEN" )
+MAX_IN_LEN=$( get_config_value_or_default "MBEDTLS_SSL_IN_CONTENT_LEN" )
+MAX_OUT_LEN=$( get_config_value_or_default "MBEDTLS_SSL_OUT_CONTENT_LEN" )
 
 # Calculate the maximum content length that fits both
 if [ "$MAX_IN_LEN" -lt "$MAX_CONTENT_LEN" ]; then