tests: Prefer permanent MAC for finding link info, fallback to curren…

…t MAC

When a network connection specifies both an interface name and MAC
address, and the physical interface has identical permanent and current
MACs, applying the configuration multiple times can cause an error:
"no such interface exists."

The issue occurs because `SysUtil.link_info_find()` may return a link
info entry where the user-specified MAC matches only the current
("address") but not the permanent MAC ("perm-address"). In such cases,
the returned link info may have a different interface name than the one
specified in the network connection, leading to the error.

We already implemented a fix (c341683) that ensures link lookup
prioritizes the permanent MAC, only falling back to the current MAC when
necessary. The integration test `tests_mac_address_match.yml` verifies
this fix by requiring an Ethernet interface where the permanent and
current MACs match.

Resolves: https://issues.redhat.com/browse/RHEL-74211

Signed-off-by: Wen Liang <[email protected]>

tests/ensure_provider_tests.py

@@ -79,6 +79,7 @@
     "playbooks/tests_infiniband.yml": {},
     "playbooks/tests_ipv6_disabled.yml": {},
     "playbooks/tests_ipv6_dns_search.yml": {},
+    "playbooks/tests_mac_address_match.yml": {},
     "playbooks/tests_provider.yml": {
         MINIMUM_VERSION: "'1.20.0'",
         "comment": "# NetworKmanager 1.20.0 added support for forgetting profiles",

tests/playbooks/tests_mac_address_match.yml

@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: BSD-3-Clause
+---
+- name: Play for testing MAC address match on device
+  hosts: all
+  vars:
+    # This test requires an Ethernet interface whose permanent
+    # MAC address matches its current MAC address. Ensure that the
+    # specified interface meets this condition.
+    #
+    # Two VLAN profiles are defined to test deterministic behavior when fetching
+    # link information from sysfs. The issue being tested arises when `os.listdir(path)`
+    # returns interfaces in an arbitrary order, potentially listing a VLAN device
+    # before its parent interface. This can cause intermittent "no such interface
+    # exists" errors when applying configurations repeatedly.
+    #
+    # - `vlan_profile1` (e.g., `eth1.3732`) is named with the VLAN ID appended
+    #   after the parent interface, following the standard `<parent>.<vlan_id>` format.
+    # - `vlan_profile2` (e.g., `120-vlan`) has a fixed name, designed to test a scenario
+    #   where lexicographic sorting causes the VLAN to appear before its parent interface.
+    interface: "{{ lookup('env', 'MAC_ADDR_MATCH_INTERFACE') | default('eth1', true) }}"
+    profile: "{{ interface }}"
+    vlan_profile1: "{{ interface }}.3732"
+    vlan_profile2: "120-vlan"
+    lsr_fail_debug:
+      - __network_connections_result
+  tags:
+    - "tests::match"
+  tasks:
+    - name: Show playbook name
+      debug:
+        msg: "this is: playbooks/tests_mac_address_match.yml"
+      tags:
+        - always
+
+    - name: Install ethtool (test dependency)
+      package:
+        name: ethtool
+        state: present
+        use: "{{ (__network_is_ostree | d(false)) |
+          ternary('ansible.posix.rhel_rpm_ostree', omit) }}"
+
+    - name: Retrieve MAC address using ethtool
+      command: ethtool -P {{ interface }}
+      register: mac_address_result
+      changed_when: false
+      failed_when: mac_address_result.rc != 0
+
+    - name: Set the MAC address variable
+      set_fact:
+        mac: "{{ mac_address_result.stdout_lines[-1].split(' ')[-1] }}"
+
+    - name: Display the retrieved MAC address
+      debug:
+        msg: "Retrieved MAC address for {{ interface }}: {{ mac }}"
+
+    - name: Test the MAC address match
+      tags:
+        - tests::match:match
+      block:
+        - name: Include the task 'run_test.yml'
+          include_tasks: tasks/run_test.yml
+          vars:
+            lsr_description: Test MAC address match on device
+            lsr_setup:
+              - tasks/remove_profile.yml
+              - tasks/assert_profile_absent.yml
+            lsr_test:
+              - tasks/create_mac_address_match.yml
+              - tasks/create_mac_address_match.yml
+            lsr_assert:
+              - tasks/assert_profile_present.yml
+              - tasks/assert_network_connections_succeeded.yml
+            lsr_cleanup:
+              - tasks/cleanup_vlan_and_parent_profile+device.yml
+              - tasks/check_network_dns.yml

tests/tasks/assert_network_connections_succeeded.yml

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: BSD-3-Clause
+---
+- name: Assert that configuring network connections is succeeded
+  assert:
+    that:
+      - __network_connections_result.failed == false
+    msg: Configuring network connections is failed with the error
+      "{{ __network_connections_result.stderr }}"

tests/tasks/cleanup_vlan_and_parent_profile+device.yml

@@ -0,0 +1,26 @@
+# SPDX-License-Identifier: BSD-3-Clause
+---
+- name: Clean up the test devices and the connection profiles
+  tags:
+    - "tests::cleanup"
+  block:
+    - name: Import network role
+      import_role:
+        name: linux-system-roles.network
+      vars:
+        network_connections:
+          - name: "{{ profile }}"
+            persistent_state: absent
+            state: down
+          - name: "{{ vlan_profile1 }}"
+            persistent_state: absent
+            state: down
+          - name: "{{ vlan_profile2 }}"
+            persistent_state: absent
+            state: down
+      failed_when: false
+    - name: Delete the device '{{ interface }}'
+      command: ip link del {{ interface }}
+      failed_when: false
+      changed_when: false
+...

tests/tasks/create_mac_address_match.yml

@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: BSD-3-Clause
+---
+- name: Include network role
+  include_role:
+    name: linux-system-roles.network
+  vars:
+    network_connections:
+      - name: "{{ interface }}"
+        state: up
+        persistent_state: present
+        autoconnect: true
+        type: ethernet
+        interface_name: "{{ interface }}"
+        mac: "{{ mac }}"
+        ip:
+          dhcp4: false
+          auto6: false
+
+      - name: "{{ vlan_profile1 }}"
+        state: up
+        persistent_state: present
+        type: vlan
+        parent: "{{ interface }}"
+        vlan:
+          id: 3732
+        autoconnect: true
+        ip:
+          auto_gateway: false
+          ipv6_disabled: true
+          gateway4: 10.10.0.1
+          address: 10.10.0.6/24
+          dhcp4: false
+          auto6: false
+
+      - name: "{{ vlan_profile2 }}"
+        state: up
+        persistent_state: present
+        type: vlan
+        parent: "{{ interface }}"
+        vlan:
+          id: 120
+        autoconnect: true
+        ip:
+          auto_gateway: false
+          ipv6_disabled: true
+          gateway4: 10.10.120.1
+          address: 10.10.120.120/24
+          dhcp4: false
+          auto6: false
+- name: Show result
+  debug:
+    var: __network_connections_result
+...

tests/tests_mac_address_match_nm.yml

@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# This file was generated by ensure_provider_tests.py
+---
+# set network provider and gather facts
+# yamllint disable rule:line-length
+- name: Run playbook 'playbooks/tests_mac_address_match.yml' with nm as provider
+  hosts: all
+  tasks:
+    - name: Include the task 'el_repo_setup.yml'
+      include_tasks: tasks/el_repo_setup.yml
+    - name: Set network provider to 'nm'
+      set_fact:
+        network_provider: nm
+      tags:
+        - always
+
+
+# The test requires or should run with NetworkManager, therefore it cannot run
+# on RHEL/CentOS 6
+- name: Import the playbook 'playbooks/tests_mac_address_match.yml'
+  import_playbook: playbooks/tests_mac_address_match.yml
+  when:
+    - ansible_distribution_major_version != '6'