Merge pull request #3352 from sysown/v2.1.1-3350

Closes #3350: Memory leak reported by Valgrind in ''MySQL_Protocol::get_binds_from_pkt"

lib/MySQL_Session.cpp

@@ -3890,6 +3890,21 @@ void MySQL_Session::handler_rc0_PROCESSING_STMT_EXECUTE(MySQL_Data_Stream *myds)
 			free(CurrentQuery.stmt_meta->pkt);
 			CurrentQuery.stmt_meta->pkt=NULL;
 		}
+
+		// free for all the buffer types in which we allocate
+		for (int i = 0; i < CurrentQuery.stmt_meta->num_params; i++) {
+			enum enum_field_types buffer_type =
+				CurrentQuery.stmt_meta->binds[i].buffer_type;
+
+			if (
+				(buffer_type == MYSQL_TYPE_TIME) ||
+				(buffer_type == MYSQL_TYPE_DATE) ||
+				(buffer_type == MYSQL_TYPE_TIMESTAMP) ||
+				(buffer_type == MYSQL_TYPE_DATETIME)
+			) {
+				free(CurrentQuery.stmt_meta->binds[i].buffer);
+			}
+		}
 	}
 	CurrentQuery.mysql_stmt=NULL;
 }

test/tap/tests/repro_test_leak_3350.cpp

@@ -0,0 +1,101 @@
+/**
+ * @file repro_test_leak_3350.cpp
+ * @brief Test to reproduce issue #3350.
+ * @details This test is not meant to be executed, it's just a left as DOC of how to
+ *   reproduce issue #3350.
+ * @date 2021-03-18
+ */
+
+#include <vector>
+#include <string>
+#include <stdio.h>
+#include <cstring>
+#include <unistd.h>
+
+#include <mysql.h>
+
+#include "tap.h"
+#include "command_line.h"
+#include "utils.h"
+
+const int NUM_EXECUTIONS = 10000;
+
+int main(int argc, char** argv) {
+	CommandLine cl;
+
+	plan(NUM_EXECUTIONS);
+
+	if (cl.getEnv()) {
+		diag("Failed to get the required environmental variables.");
+		return -1;
+	}
+
+	MYSQL* mysql = mysql_init(NULL);
+	if (!mysql) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(mysql));
+		return exit_status();
+	}
+
+	if (!mysql_real_connect(mysql, cl.host, cl.username, cl.password, NULL, 6033, NULL, 0)) {
+		fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(mysql));
+		return exit_status();
+	}
+
+	std::string select_query { "SELECT DAY(?)" };
+
+	// Initialize and prepare the statement
+	MYSQL_STMT* stmt = mysql_stmt_init(mysql);
+	if (!stmt) {
+		ok(false, "mysql_stmt_init(), out of memory\n");
+		return exit_status();
+	}
+
+	MYSQL_TIME ts;
+	MYSQL_BIND bind;
+
+	if (mysql_stmt_prepare(stmt, select_query.c_str(), strlen(select_query.c_str()))) {
+		diag("select_query: %s", select_query.c_str());
+		ok(false, "mysql_stmt_prepare at line %d failed: %s\n", __LINE__ , mysql_error(mysql));
+		mysql_close(mysql);
+		mysql_library_end();
+		return exit_status();
+	}
+
+	/* set up input buffers for all 3 parameters */
+	bind.buffer_type= MYSQL_TYPE_DATE;
+	bind.buffer= (char *)&ts;
+	bind.is_null= 0;
+	bind.length= 0;
+
+	mysql_stmt_bind_param(stmt, &bind);
+
+	ts.year= 2002;
+	ts.month= 2;
+	ts.day= 3;
+
+	ts.hour= 10;
+	ts.minute= 45;
+	ts.second= 20;
+
+	// Execute the prepared statement and check that the field count is correct after doing the execute
+	for (int i = 0; i < NUM_EXECUTIONS; i++) {
+
+		if (mysql_stmt_execute(stmt)) {
+			ok(false, "mysql_stmt_execute at line %d failed: %s\n", __LINE__ , mysql_stmt_error(stmt));
+		}
+		if (mysql_stmt_fetch(stmt)) {
+			ok(false, "mysql_stmt_fetch at line %d failed: %s\n", __LINE__ , mysql_stmt_error(stmt));
+		}
+
+		int field_count = mysql_stmt_field_count(stmt);
+		ok(field_count == 1, "Field count should be '1'");
+	}
+
+	if (mysql_stmt_close(stmt)) {
+		ok(false, "mysql_stmt_close at line %d failed: %s\n", __LINE__ , mysql_error(mysql));
+	}
+
+	mysql_close(mysql);
+
+	return exit_status();
+}