Merge pull request #20359 from LabNConsulting/chopps/20356-backport

backport of 20536: Fix mgmtd abort (core) during exit with in-progress config change

Author: ton31337

lib/vty.c

@@ -4154,11 +4154,6 @@ void vty_terminate(void)
 {
 	struct vty *vty;
 
-	if (mgmt_fe_client) {
-		mgmt_fe_client_destroy(mgmt_fe_client);
-		mgmt_fe_client = NULL;
-	}
-
 	memset(vty_cwd, 0x00, sizeof(vty_cwd));
 
 	vty_reset();
@@ -4178,5 +4173,10 @@ void vty_terminate(void)
 	vtys_fini(vtysh_sessions);
 	vtys_init(vtysh_sessions);
 
+	if (mgmt_fe_client) {
+		mgmt_fe_client_destroy(mgmt_fe_client);
+		mgmt_fe_client = NULL;
+	}
+
 	vty_serv_stop();
 }

tests/topotests/conftest.py

@@ -20,7 +20,7 @@
 from lib.common_config import generate_support_bundle
 from lib.topogen import diagnose_env, get_topogen
 from lib.topolog import get_test_logdir, logger
-from lib.topotest import json_cmp_result, gdb_core
+from lib.topotest import gdb_core, json_cmp_result
 from munet import cli
 from munet.base import BaseMunet, Commander, proc_error
 from munet.cleanup import cleanup_current, cleanup_previous
@@ -357,7 +357,9 @@ def check_for_core_dumps():
         tgen.existing_core_files = set()
     existing = tgen.existing_core_files
 
-    cores = glob.glob(os.path.join(tgen.logdir, "*/*.dmp"))
+    cores = glob.glob(f"{tgen.logdir}/**/*.dmp", recursive=True)
+    if cores:
+        logging.info("Found core dumps: %s", cores)
     latest = {x for x in cores if x not in existing}
     if latest:
         existing |= latest

tests/topotests/mgmt_config/test_exit_core.py

@@ -0,0 +1,91 @@
+# SPDX-License-Identifier: ISC
+# -*- coding: utf-8 eval: (blacken-mode 1) -*-
+#
+# December 31 2025, Christian Hopps <chopps@labn.net>
+#
+# Copyright (c) 2025, LabN Consulting, L.L.C.
+#
+"""
+Test static route functionality
+"""
+import datetime
+import logging
+import os
+import re
+import time
+
+import pytest
+from lib.common_config import step
+from lib.topogen import Topogen
+from munet.base import Timeout
+from munet.watchlog import WatchLog
+
+pytestmark = [pytest.mark.staticd]
+
+
+@pytest.fixture(scope="function")
+def tgen(request):
+    "Setup/Teardown the environment and provide tgen argument to tests"
+
+    topodef = {
+        "s1": ("r1",),
+    }
+
+    tgen = Topogen(topodef, request.module.__name__)
+    tgen.start_topology()
+
+    for router in tgen.routers().values():
+        router.load_frr_config("frr.conf")
+
+    tgen.start_router()
+    yield tgen
+    tgen.stop_topology()
+
+
+def scan_for_match(wl, regex, timeout=30):
+    regex = re.compile(regex)
+    to = Timeout(timeout)
+    logging.debug("scanning %s for %s", wl.path, regex)
+    while to:
+        content = wl.snapshot_refresh()
+        if m := regex.search(content):
+            logging.debug("found '%s' in %s", m.group(0), wl.path)
+            return m
+        time.sleep(0.5)
+    raise TimeoutError(f"timeout waiting for {regex} in {wl.path}")
+
+def test_quit_during_config(tgen):
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    r1g = tgen.gears["r1"]
+    r1 = r1g.net
+    wl = WatchLog(r1.rundir / "mgmtd.log")
+
+    # Get a config file with `count` static IPv4 routes
+    count = 10 * 1024
+    config_file = os.path.join(r1.logdir, "bigconfig.conf")
+    with open(config_file, "w") as cfile:
+        for i in range((1 << 24), (1 << 24) + count * 4, 4):
+            dq0 = (i >> 24) & 0xff
+            dq1 = (i >> 16) & 0xff
+            dq2 = (i >> 8) & 0xff
+            dq3 = i & 0xff
+            cfile.write(f"ip route {dq0}.{dq1}.{dq2}.{dq3}/30 101.0.0.2\n")
+
+    step(f"add {count} static routes", reset=True)
+    load_command = 'vtysh -f "{}"'.format(config_file)
+
+    wl.snapshot()
+    config_proc = r1.popen(load_command)
+    try:
+
+        # Wait for part of the configuration to start being applied
+        scan_for_match(wl, re.escape(r"ip route 1.0.1.0/30 101.0.0.2"))
+        logging.info("partial config applied, waiting for completion")
+
+        # Now stop the router to see if we get any core files
+        r1.stopRouter(False)
+    finally:
+        if config_proc:
+            config_proc.kill()