[20608][20610] Address XMLProfiles fuzzer regressions

src/cpp/rtps/participant/RTPSParticipantImpl.cpp

@@ -150,14 +150,14 @@ static void set_builtin_transports_from_env_var(
                 if (std::regex_search(env_value, mr, msg_size_regex, std::regex_constants::match_not_null))
                 {
                     std::string value = mr[2];
-                    std::string unit = (mr[3] == "") ? "B" : mr[3].str();
+                    std::string unit = mr[3].str();
                     options.maxMessageSize = eprosima::fastdds::dds::utils::parse_value_and_units(value, unit);
                 }
                 // Sockets_size parser
                 if (std::regex_search(env_value, mr, sockets_size_regex, std::regex_constants::match_not_null))
                 {
                     std::string value = mr[2];
-                    std::string unit = (mr[3] == "") ? "B" : mr[3].str();
+                    std::string unit = mr[3].str();
                     options.sockets_buffer_size = eprosima::fastdds::dds::utils::parse_value_and_units(value, unit);
                 }
                 // Non-blocking-send parser

src/cpp/rtps/xmlparser/XMLElementParser.cpp

@@ -4767,7 +4767,7 @@ XMLP_ret XMLParser::getXMLBuiltinTransports(
                 if (std::regex_search(temp, mr, msg_size_regex, std::regex_constants::match_not_null))
                 {
                     std::string value = mr[1];
-                    std::string unit = (mr[2] == "") ? "B" : mr[2].str();
+                    std::string unit = mr[2].str();
                     bt_opts->maxMessageSize = eprosima::fastdds::dds::utils::parse_value_and_units(value, unit);
                 }
             }
@@ -4799,7 +4799,7 @@ XMLP_ret XMLParser::getXMLBuiltinTransports(
                 if (std::regex_search(temp, mr, sockets_size_regex, std::regex_constants::match_not_null))
                 {
                     std::string value = mr[1];
-                    std::string unit = (mr[2] == "") ? "B" : mr[2].str();
+                    std::string unit = mr[2].str();
                     bt_opts->sockets_buffer_size = eprosima::fastdds::dds::utils::parse_value_and_units(value, unit);
                 }
             }

src/cpp/utils/UnitsParser.cpp

@@ -55,6 +55,7 @@ uint32_t parse_value_and_units(
         std::string units)
 {
     static const std::map<std::string, std::uint32_t> magnitudes = {
+        {"", 1},
         {"B", 1},
         {"KB", 1000},
         {"MB", 1000 * 1000},
@@ -64,16 +65,29 @@ uint32_t parse_value_and_units(
         {"GIB", 1024 * 1024 * 1024},
     };
 
-    uint64_t num = std::stoull(value);
+    uint64_t num = 0;
+    try
+    {
+        num = std::stoull(value);
+    }
+    catch (std::out_of_range&)
+    {
+        throw std::invalid_argument("Failed to parse value from string." \
+                      " The number is too large to be converted to bytes (Max: (2^32)-1 Bytes).");
+    }
+
     to_uppercase(units);
 
-    std::regex pattern(R"(([kibmgKIBMG]{1,3})|(\d+))");
-    if (!std::regex_match(units, pattern))
+    uint32_t magnitude = 0;
+    try
+    {
+        magnitude = magnitudes.at(units);
+    }
+    catch (std::out_of_range&)
     {
         throw std::invalid_argument(
                   "The units are not in the expected format. Use: {B, KB, MG, GB, KIB, MIB, GIB}.");
     }
-    const auto magnitude = magnitudes.at(units);
 
     // Check whether the product of number * magnitude overflows
     if (num > std::numeric_limits<std::uint32_t>::max() / magnitude)

test/unittest/xmlparser/XMLParserTests.cpp

@@ -72,6 +72,8 @@ TEST_F(XMLParserTests, regressions)
     EXPECT_EQ(XMLP_ret::XML_OK, XMLParser::loadXML("regressions/simple_participant_profiles_ok.xml", root));
     EXPECT_EQ(XMLP_ret::XML_ERROR, XMLParser::loadXML("regressions/20186_profile_bin.xml", root));
     EXPECT_EQ(XMLP_ret::XML_ERROR, XMLParser::loadXML("regressions/20187_profile_bin.xml", root));
+    EXPECT_EQ(XMLP_ret::XML_ERROR, XMLParser::loadXML("regressions/20608_profile_bin.xml", root));
+    EXPECT_EQ(XMLP_ret::XML_ERROR, XMLParser::loadXML("regressions/20610_profile_bin.xml", root));
 }
 
 TEST_F(XMLParserTests, NoFile)

test/unittest/xmlparser/regressions/20608_profile_bin.xml

@@ -0,0 +1 @@
+<profiles><participant><rtps><builtinTransports max_msg_size="88888888888888888884"/></rtps></participant></profiles>

test/unittest/xmlparser/regressions/20610_profile_bin.xml

@@ -0,0 +1 @@
+<profiles><participant><rtps><builtinTransports max_msg_size="1i"/></rtps></participant></profiles>