Merge pull request #4722 from sysown/v2.7_reg_test_4716_single_semicolon

Fixed crash when a lone semicolon (;) is sent as input (Admin Interface) - v2.7

lib/ProxySQL_Admin.cpp

@@ -3761,12 +3761,20 @@ void admin_session_handler(MySQL_Session *sess, void *_pa, PtrSize_t *pkt) {
 
 	if (query_no_space_length) {
 		// fix bug #925
-		while (query_no_space[query_no_space_length-1]==';' || query_no_space[query_no_space_length-1]==' ') {
+		while (query_no_space_length &&
+			(query_no_space[query_no_space_length-1]==';' || query_no_space[query_no_space_length-1]==' ')) {
 			query_no_space_length--;
 			query_no_space[query_no_space_length]=0;
 		}
 	}
 
+	if (query_no_space_length == 0) {
+		proxy_warning("Empty query\n");
+		SPA->send_MySQL_ERR(&sess->client_myds->myprot, (char*)"Empty query");
+		run_query = false;
+		goto __run_query;
+	}
+
 	// add global mutex, see bug #1188
 	pthread_mutex_lock(&pa->sql_query_global_mutex);
 

test/tap/tests/mysql-reg_test_4716_single_semicolon-t.cpp

@@ -0,0 +1,64 @@
+ /**
+  * @file mysql-reg_test_4716_single_semicolon-t.cpp
+  * @brief  This test aims to verify that ProxySQL handles a lone semicolon (;) input
+  * crashing. The expected behavior is for ProxySQL to either ignore the input or return an
+  * appropriate error message, rather than crashing or becoming unresponsive.
+  */
+
+#include <string>
+#include <sstream>
+
+#include "mysql.h"
+#include "command_line.h"
+#include "tap.h"
+#include "utils.h"
+
+CommandLine cl;
+
+enum ConnType {
+    ADMIN,
+    BACKEND
+};
+
+int main(int argc, char** argv) {
+
+    std::vector<const char*> queries = { ";", " ", "", ";  ", "  ;" };
+
+    plan(queries.size() + 1); // Total number of tests planned
+
+    if (cl.getEnv())
+        return exit_status();
+
+    // Initialize Admin connection
+    MYSQL* proxysql_admin = mysql_init(NULL);
+    if (!proxysql_admin) {
+        fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql_admin));
+        return -1;
+    }
+
+    // Connnect to ProxySQL Admin
+    if (!mysql_real_connect(proxysql_admin, cl.admin_host, cl.admin_username, cl.admin_password, NULL, cl.admin_port, NULL, 0)) {
+        fprintf(stderr, "File %s, line %d, Error: %s\n", __FILE__, __LINE__, mysql_error(proxysql_admin));
+        return -1;
+    }
+
+    for (const char* query : queries) {
+        MYSQL_QUERY_err(proxysql_admin, query);
+        const int _errorno = mysql_errno(proxysql_admin);
+        ok(_errorno > 0, "Error Code:%d, Message:%s", _errorno, mysql_error(proxysql_admin));
+    }
+
+    // Test a valid query to ensure the connection is working
+    if (mysql_query(proxysql_admin, "SELECT 1") == 0) {
+        MYSQL_RES* res = mysql_store_result(proxysql_admin);
+        ok(res != nullptr, "Query executed successfully. %s", mysql_error(proxysql_admin));
+        mysql_free_result(res);
+    }
+    else {
+        ok(false, "Error executing query. %s", mysql_error(proxysql_admin));
+    }
+
+    mysql_close(proxysql_admin);
+
+    return exit_status();
+}