Merge pull request #20375 from yuwata/network-bridge-vlan-issue-20373

network: fix bridge and openvswitch issues

src/core/bpf-devices.c

@@ -9,6 +9,7 @@
 #include "fileio.h"
 #include "nulstr-util.h"
 #include "parse-util.h"
+#include "path-util.h"
 #include "stat-util.h"
 #include "stdio-util.h"
 #include "string-util.h"
@@ -260,7 +261,7 @@ int bpf_devices_apply_policy(
         r = bpf_program_cgroup_attach(prog, BPF_CGROUP_DEVICE, controller_path, BPF_F_ALLOW_MULTI);
         if (r < 0)
                 return log_error_errno(r, "Attaching device control BPF program to cgroup %s failed: %m",
-                                       cgroup_path);
+                                       empty_to_root(cgroup_path));
 
  finish:
         /* Unref the old BPF program (which will implicitly detach it) right before attaching the new program. */

src/core/cgroup.c

@@ -84,7 +84,7 @@ static int set_attribute_and_warn(Unit *u, const char *controller, const char *a
         r = cg_set_attribute(controller, u->cgroup_path, attribute, value);
         if (r < 0)
                 log_unit_full_errno(u, LOG_LEVEL_CGROUP_WRITE(r), r, "Failed to set '%s' attribute on '%s' to '%.*s': %m",
-                                    strna(attribute), isempty(u->cgroup_path) ? "/" : u->cgroup_path, (int) strcspn(value, NEWLINE), value);
+                                    strna(attribute), empty_to_root(u->cgroup_path), (int) strcspn(value, NEWLINE), value);
 
         return r;
 }
@@ -706,25 +706,25 @@ void cgroup_oomd_xattr_apply(Unit *u, const char *cgroup_path) {
         if (c->moom_preference == MANAGED_OOM_PREFERENCE_OMIT) {
                 r = cg_set_xattr(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, "user.oomd_omit", "1", 1, 0);
                 if (r < 0)
-                        log_unit_debug_errno(u, r, "Failed to set oomd_omit flag on control group %s, ignoring: %m", cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to set oomd_omit flag on control group %s, ignoring: %m", empty_to_root(cgroup_path));
         }
 
         if (c->moom_preference == MANAGED_OOM_PREFERENCE_AVOID) {
                 r = cg_set_xattr(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, "user.oomd_avoid", "1", 1, 0);
                 if (r < 0)
-                        log_unit_debug_errno(u, r, "Failed to set oomd_avoid flag on control group %s, ignoring: %m", cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to set oomd_avoid flag on control group %s, ignoring: %m", empty_to_root(cgroup_path));
         }
 
         if (c->moom_preference != MANAGED_OOM_PREFERENCE_AVOID) {
                 r = cg_remove_xattr(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, "user.oomd_avoid");
-                if (r != -ENODATA)
+                if (r < 0 && r != -ENODATA)
-                        log_unit_debug_errno(u, r, "Failed to remove oomd_avoid flag on control group %s, ignoring: %m", cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to remove oomd_avoid flag on control group %s, ignoring: %m", empty_to_root(cgroup_path));
         }
 
         if (c->moom_preference != MANAGED_OOM_PREFERENCE_OMIT) {
                 r = cg_remove_xattr(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, "user.oomd_omit");
-                if (r != -ENODATA)
+                if (r < 0 && r != -ENODATA)
-                        log_unit_debug_errno(u, r, "Failed to remove oomd_omit flag on control group %s, ignoring: %m", cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to remove oomd_omit flag on control group %s, ignoring: %m", empty_to_root(cgroup_path));
         }
 }
 
@@ -743,7 +743,7 @@ static void cgroup_xattr_apply(Unit *u) {
                                  sd_id128_to_string(u->invocation_id, ids), 32,
                                  0);
                 if (r < 0)
-                        log_unit_debug_errno(u, r, "Failed to set invocation ID on control group %s, ignoring: %m", u->cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to set invocation ID on control group %s, ignoring: %m", empty_to_root(u->cgroup_path));
         }
 
         if (unit_cgroup_delegate(u)) {
@@ -752,11 +752,11 @@ static void cgroup_xattr_apply(Unit *u) {
                                  "1", 1,
                                  0);
                 if (r < 0)
-                        log_unit_debug_errno(u, r, "Failed to set delegate flag on control group %s, ignoring: %m", u->cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to set delegate flag on control group %s, ignoring: %m", empty_to_root(u->cgroup_path));
         } else {
                 r = cg_remove_xattr(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, "trusted.delegate");
-                if (r != -ENODATA)
+                if (r < 0 && r != -ENODATA)
-                        log_unit_debug_errno(u, r, "Failed to remove delegate flag on control group %s, ignoring: %m", u->cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to remove delegate flag on control group %s, ignoring: %m", empty_to_root(u->cgroup_path));
         }
 
         cgroup_oomd_xattr_apply(u, u->cgroup_path);
@@ -1913,12 +1913,12 @@ int unit_watch_cgroup(Unit *u) {
                                       * is not an error */
                         return 0;
 
-                return log_unit_error_errno(u, errno, "Failed to add control inotify watch descriptor for control group %s: %m", u->cgroup_path);
+                return log_unit_error_errno(u, errno, "Failed to add control inotify watch descriptor for control group %s: %m", empty_to_root(u->cgroup_path));
         }
 
         r = hashmap_put(u->manager->cgroup_control_inotify_wd_unit, INT_TO_PTR(u->cgroup_control_inotify_wd), u);
         if (r < 0)
-                return log_unit_error_errno(u, r, "Failed to add control inotify watch descriptor to hash map: %m");
+                return log_unit_error_errno(u, r, "Failed to add control inotify watch descriptor for control group %s to hash map: %m", empty_to_root(u->cgroup_path));
 
         return 0;
 }
@@ -1976,12 +1976,12 @@ int unit_watch_cgroup_memory(Unit *u) {
                                       * is not an error */
                         return 0;
 
-                return log_unit_error_errno(u, errno, "Failed to add memory inotify watch descriptor for control group %s: %m", u->cgroup_path);
+                return log_unit_error_errno(u, errno, "Failed to add memory inotify watch descriptor for control group %s: %m", empty_to_root(u->cgroup_path));
         }
 
         r = hashmap_put(u->manager->cgroup_memory_inotify_wd_unit, INT_TO_PTR(u->cgroup_memory_inotify_wd), u);
         if (r < 0)
-                return log_unit_error_errno(u, r, "Failed to add memory inotify watch descriptor to hash map: %m");
+                return log_unit_error_errno(u, r, "Failed to add memory inotify watch descriptor for control group %s to hash map: %m", empty_to_root(u->cgroup_path));
 
         return 0;
 }
@@ -2004,9 +2004,9 @@ int unit_pick_cgroup_path(Unit *u) {
 
         r = unit_set_cgroup_path(u, path);
         if (r == -EEXIST)
-                return log_unit_error_errno(u, r, "Control group %s exists already.", path);
+                return log_unit_error_errno(u, r, "Control group %s exists already.", empty_to_root(path));
         if (r < 0)
-                return log_unit_error_errno(u, r, "Failed to set unit's control group path to %s: %m", path);
+                return log_unit_error_errno(u, r, "Failed to set unit's control group path to %s: %m", empty_to_root(path));
 
         return 0;
 }
@@ -2034,7 +2034,7 @@ static int unit_update_cgroup(
         /* First, create our own group */
         r = cg_create_everywhere(u->manager->cgroup_supported, target_mask, u->cgroup_path);
         if (r < 0)
-                return log_unit_error_errno(u, r, "Failed to create cgroup %s: %m", u->cgroup_path);
+                return log_unit_error_errno(u, r, "Failed to create cgroup %s: %m", empty_to_root(u->cgroup_path));
         created = r;
 
         /* Start watching it */
@@ -2050,7 +2050,7 @@ static int unit_update_cgroup(
                 /* Enable all controllers we need */
                 r = cg_enable_everywhere(u->manager->cgroup_supported, enable_mask, u->cgroup_path, &result_mask);
                 if (r < 0)
-                        log_unit_warning_errno(u, r, "Failed to enable/disable controllers on cgroup %s, ignoring: %m", u->cgroup_path);
+                        log_unit_warning_errno(u, r, "Failed to enable/disable controllers on cgroup %s, ignoring: %m", empty_to_root(u->cgroup_path));
 
                 /* Remember what's actually enabled now */
                 u->cgroup_enabled_mask = result_mask;
@@ -2072,12 +2072,12 @@ static int unit_update_cgroup(
         if (cg_all_unified() == 0) {
                 r = cg_migrate_v1_controllers(u->manager->cgroup_supported, migrate_mask, u->cgroup_path, migrate_callback, u);
                 if (r < 0)
-                        log_unit_warning_errno(u, r, "Failed to migrate controller cgroups from %s, ignoring: %m", u->cgroup_path);
+                        log_unit_warning_errno(u, r, "Failed to migrate controller cgroups from %s, ignoring: %m", empty_to_root(u->cgroup_path));
 
                 is_root_slice = unit_has_name(u, SPECIAL_ROOT_SLICE);
                 r = cg_trim_v1_controllers(u->manager->cgroup_supported, ~target_mask, u->cgroup_path, !is_root_slice);
                 if (r < 0)
-                        log_unit_warning_errno(u, r, "Failed to delete controller cgroups %s, ignoring: %m", u->cgroup_path);
+                        log_unit_warning_errno(u, r, "Failed to delete controller cgroups %s, ignoring: %m", empty_to_root(u->cgroup_path));
         }
 
         /* Set attributes */
@@ -2167,7 +2167,7 @@ int unit_attach_pids_to_cgroup(Unit *u, Set *pids, const char *suffix_path) {
 
                         log_unit_full_errno(u, again ? LOG_DEBUG : LOG_INFO,  q,
                                             "Couldn't move process "PID_FMT" to%s requested cgroup '%s': %m",
-                                            pid, again ? " directly" : "", p);
+                                            pid, again ? " directly" : "", empty_to_root(p));
 
                         if (again) {
                                 int z;
@@ -2179,7 +2179,7 @@ int unit_attach_pids_to_cgroup(Unit *u, Set *pids, const char *suffix_path) {
 
                                 z = unit_attach_pid_to_cgroup_via_bus(u, pid, suffix_path);
                                 if (z < 0)
-                                        log_unit_info_errno(u, z, "Couldn't move process "PID_FMT" to requested cgroup '%s' (directly or via the system bus): %m", pid, p);
+                                        log_unit_info_errno(u, z, "Couldn't move process "PID_FMT" to requested cgroup '%s' (directly or via the system bus): %m", pid, empty_to_root(p));
                                 else
                                         continue; /* When the bus thing worked via the bus we are fully done for this PID. */
                         }
@@ -2213,7 +2213,7 @@ int unit_attach_pids_to_cgroup(Unit *u, Set *pids, const char *suffix_path) {
                                         continue; /* Success! */
 
                                 log_unit_debug_errno(u, q, "Failed to attach PID " PID_FMT " to requested cgroup %s in controller %s, falling back to unit's cgroup: %m",
-                                                     pid, p, cgroup_controller_to_string(c));
+                                                     pid, empty_to_root(p), cgroup_controller_to_string(c));
                         }
 
                         /* So this controller is either not delegate or realized, or something else weird happened. In
@@ -2648,7 +2648,7 @@ void unit_prune_cgroup(Unit *u) {
                  * the containing slice is stopped. So even if we failed now, this unit shouldn't assume
                  * that the cgroup is still realized the next time it is started. Do not return early
                  * on error, continue cleanup. */
-                log_unit_full_errno(u, r == -EBUSY ? LOG_DEBUG : LOG_WARNING, r, "Failed to destroy cgroup %s, ignoring: %m", u->cgroup_path);
+                log_unit_full_errno(u, r == -EBUSY ? LOG_DEBUG : LOG_WARNING, r, "Failed to destroy cgroup %s, ignoring: %m", empty_to_root(u->cgroup_path));
 
         if (is_root_slice)
                 return;
@@ -2861,7 +2861,7 @@ void unit_add_to_cgroup_empty_queue(Unit *u) {
 
         r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
         if (r < 0) {
-                log_unit_debug_errno(u, r, "Failed to determine whether cgroup %s is empty: %m", u->cgroup_path);
+                log_unit_debug_errno(u, r, "Failed to determine whether cgroup %s is empty: %m", empty_to_root(u->cgroup_path));
                 return;
         }
         if (r == 0)

src/core/unit.c

@@ -427,7 +427,7 @@ bool unit_may_gc(Unit *u) {
 
                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
                 if (r < 0)
-                        log_unit_debug_errno(u, r, "Failed to determine whether cgroup %s is empty: %m", u->cgroup_path);
+                        log_unit_debug_errno(u, r, "Failed to determine whether cgroup %s is empty: %m", empty_to_root(u->cgroup_path));
                 if (r <= 0)
                         return false;
         }
@@ -4548,7 +4548,7 @@ int unit_kill_context(
                                       log_func, u);
                 if (r < 0) {
                         if (!IN_SET(r, -EAGAIN, -ESRCH, -ENOENT))
-                                log_unit_warning_errno(u, r, "Failed to kill control group %s, ignoring: %m", u->cgroup_path);
+                                log_unit_warning_errno(u, r, "Failed to kill control group %s, ignoring: %m", empty_to_root(u->cgroup_path));
 
                 } else if (r > 0) {
 
@@ -5006,7 +5006,7 @@ int unit_fork_helper_process(Unit *u, const char *name, pid_t *ret) {
         if (u->cgroup_path) {
                 r = cg_attach_everywhere(u->manager->cgroup_supported, u->cgroup_path, 0, NULL, NULL);
                 if (r < 0) {
-                        log_unit_error_errno(u, r, "Failed to join unit cgroup %s: %m", u->cgroup_path);
+                        log_unit_error_errno(u, r, "Failed to join unit cgroup %s: %m", empty_to_root(u->cgroup_path));
                         _exit(EXIT_CGROUP);
                 }
         }

src/libsystemd-network/sd-dhcp6-client.c

@@ -1479,15 +1479,16 @@ static int client_receive_message(
                 return 0;
         }
 
-        if (client->transaction_id != (message->transaction_id &
+        if (client->transaction_id != (message->transaction_id & htobe32(0x00ffffff)))
-                                       htobe32(0x00ffffff)))
                 return 0;
 
         switch (client->state) {
         case DHCP6_STATE_INFORMATION_REQUEST:
                 r = client_receive_reply(client, message, len);
-                if (r < 0)
+                if (r < 0) {
+                        log_dhcp6_client_errno(client, r, "Failed to process received reply message, ignoring: %m");
                         return 0;
+                }
 
                 client_notify(client, SD_DHCP6_CLIENT_EVENT_INFORMATION_REQUEST);
 
@@ -1497,10 +1498,13 @@ static int client_receive_message(
 
         case DHCP6_STATE_SOLICITATION:
                 r = client_receive_advertise(client, message, len);
+                if (r < 0) {
+                        log_dhcp6_client_errno(client, r, "Failed to process received advertise message, ignoring: %m");
+                        return 0;
+                }
 
                 if (r == DHCP6_STATE_REQUEST) {
                         client_start(client, r);
-
                         break;
                 }
 
@@ -1510,11 +1514,12 @@ static int client_receive_message(
         case DHCP6_STATE_REBIND:
 
                 r = client_receive_reply(client, message, len);
-                if (r < 0)
+                if (r < 0) {
+                        log_dhcp6_client_errno(client, r, "Failed to process received reply message, ignoring: %m");
                         return 0;
+                }
 
                 if (r == DHCP6_STATE_BOUND) {
-
                         r = client_start(client, DHCP6_STATE_BOUND);
                         if (r < 0) {
                                 client_stop(client, r);

src/network/networkd-setlink.c

@@ -95,9 +95,16 @@ static int set_link_handler_internal(
         return 1;
 
 on_error:
-        if (op == SET_LINK_FLAGS) {
+        switch (op) {
+        case SET_LINK_FLAGS:
                 assert(link->set_flags_messages > 0);
                 link->set_flags_messages--;
+                break;
+        case SET_LINK_MASTER:
+                link->master_set = true;
+                break;
+        default:
+                break;
         }
 
         return 0;
@@ -106,7 +113,7 @@ on_error:
 static int link_set_addrgen_mode_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
         int r;
 
-        r = set_link_handler_internal(rtnl, m, link, SET_LINK_ADDRESS_GENERATION_MODE, true, NULL);
+        r = set_link_handler_internal(rtnl, m, link, SET_LINK_ADDRESS_GENERATION_MODE, /* ignore = */ true, NULL);
         if (r <= 0)
                 return r;
 
@@ -120,31 +127,31 @@ static int link_set_addrgen_mode_handler(sd_netlink *rtnl, sd_netlink_message *m
 }
 
 static int link_set_bond_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_BOND, false, NULL);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_BOND, /* ignore = */ false, NULL);
 }
 
 static int link_set_bridge_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_BRIDGE, false, NULL);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_BRIDGE, /* ignore = */ true, NULL);
 }
 
 static int link_set_bridge_vlan_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_BRIDGE_VLAN, false, NULL);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_BRIDGE_VLAN, /* ignore = */ false, NULL);
 }
 
 static int link_set_can_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_CAN, false, NULL);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_CAN, /* ignore = */ false, NULL);
 }
 
 static int link_set_flags_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_FLAGS, false, get_link_update_flag_handler);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_FLAGS, /* ignore = */ false, get_link_update_flag_handler);
 }
 
 static int link_set_group_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_GROUP, false, NULL);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_GROUP, /* ignore = */ false, NULL);
 }
 
 static int link_set_mac_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_MAC, true, get_link_default_handler);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_MAC, /* ignore = */ true, get_link_default_handler);
 }
 
 static int link_set_mac_allow_retry_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
@@ -180,13 +187,18 @@ static int link_set_mac_allow_retry_handler(sd_netlink *rtnl, sd_netlink_message
 }
 
 static int link_set_master_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
-        return set_link_handler_internal(rtnl, m, link, SET_LINK_MASTER, false, get_link_master_handler);
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_MASTER, /* ignore = */ false, get_link_master_handler);
+}
+
+static int link_unset_master_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
+        /* Some devices do not support setting master ifindex. Let's ignore error on unsetting master ifindex. */
+        return set_link_handler_internal(rtnl, m, link, SET_LINK_MASTER, /* ignore = */ true, get_link_master_handler);
 }
 
 static int link_set_mtu_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
         int r;
 
-        r = set_link_handler_internal(rtnl, m, link, SET_LINK_MTU, true, get_link_default_handler);
+        r = set_link_handler_internal(rtnl, m, link, SET_LINK_MTU, /* ignore = */ true, get_link_default_handler);
         if (r <= 0)
                 return r;
 
@@ -745,10 +757,14 @@ int link_request_to_set_mac(Link *link, bool allow_retry) {
 
 int link_request_to_set_master(Link *link) {
         assert(link);
+        assert(link->network);
 
         link->master_set = false;
 
+        if (link->network->batadv || link->network->bond || link->network->bridge || link->network->vrf)
                 return link_request_set_link(link, SET_LINK_MASTER, link_set_master_handler, NULL);
+        else
+                return link_request_set_link(link, SET_LINK_MASTER, link_unset_master_handler, NULL);
 }
 
 int link_request_to_set_mtu(Link *link, uint32_t mtu) {

test/test-network/conf/26-bridge-issue-20373.netdev

@@ -0,0 +1,12 @@
+[NetDev]
+Name=bridge99
+Kind=bridge
+
+[Bridge]
+MulticastQuerier=yes
+MulticastSnooping=yes
+Priority=10
+STP=yes
+ForwardDelaySec=5
+MulticastIGMPVersion=2
+VLANFiltering=yes

test/test-network/conf/26-bridge-vlan-master-issue-20373.network

@@ -0,0 +1,20 @@
+[Match]
+Name=bridge99
+
+[Network]
+VLAN=vlan99
+IPForward=yes
+ConfigureWithoutCarrier=yes
+LLDP=yes
+IPv6AcceptRA=false
+
+[Bridge]
+Learning=yes
+MulticastRouter=no
+UseBPDU=yes
+
+[BridgeVLAN]
+VLAN=100
+
+[BridgeVLAN]
+VLAN=600

test/test-network/conf/26-bridge-vlan-slave-issue-20373.network

@@ -0,0 +1,29 @@
+[Match]
+Name=test1
+
+[Network]
+IPv6AcceptRA=no
+IPForward=yes
+Bridge=bridge99
+LinkLocalAddressing=no
+EmitLLDP=nearest-bridge
+LLDP=yes
+
+[Link]
+RequiredForOnline=no
+
+[Bridge]
+Learning=yes
+MulticastRouter=query
+UseBPDU=yes
+
+[BridgeVLAN]
+VLAN=100
+EgressUntagged=100
+PVID=100
+
+[BridgeVLAN]
+VLAN=560
+
+[BridgeVLAN]
+VLAN=600

test/test-network/systemd-networkd-tests.py

@@ -3425,21 +3425,29 @@ class NetworkdBridgeTests(unittest.TestCase, Utilities):
     links = [
         'bridge99',
         'dummy98',
-        'test1']
+        'test1',
+        'vlan99',
+    ]
 
     units = [
         '11-dummy.netdev',
         '12-dummy.netdev',
+        '21-vlan.netdev',
+        '21-vlan.network',
         '26-bridge.netdev',
         '26-bridge-configure-without-carrier.network',
+        '26-bridge-issue-20373.netdev',
         '26-bridge-mdb-master.network',
         '26-bridge-mdb-slave.network',
         '26-bridge-slave-interface-1.network',
         '26-bridge-slave-interface-2.network',
+        '26-bridge-vlan-master-issue-20373.network',
         '26-bridge-vlan-master.network',
+        '26-bridge-vlan-slave-issue-20373.network',
         '26-bridge-vlan-slave.network',
         'bridge99-ignore-carrier-loss.network',
-        'bridge99.network']
+        'bridge99.network'
+    ]
 
     routing_policy_rule_tables = ['100']
 
@@ -3474,6 +3482,25 @@ class NetworkdBridgeTests(unittest.TestCase, Utilities):
             self.assertRegex(output, f'{i}')
         self.assertNotRegex(output, '4095')
 
+    def test_bridge_vlan_issue_20373(self):
+        copy_unit_to_networkd_unit_path('11-dummy.netdev', '26-bridge-vlan-slave-issue-20373.network',
+                                        '26-bridge-issue-20373.netdev', '26-bridge-vlan-master-issue-20373.network',
+                                        '21-vlan.netdev', '21-vlan.network')
+        start_networkd()
+        self.wait_online(['test1:enslaved', 'bridge99:degraded', 'vlan99:routable'])
+
+        output = check_output('bridge vlan show dev test1')
+        print(output)
+        self.assertIn('100 PVID Egress Untagged', output)
+        self.assertIn('560', output)
+        self.assertIn('600', output)
+
+        output = check_output('bridge vlan show dev bridge99')
+        print(output)
+        self.assertIn('1 PVID Egress Untagged', output)
+        self.assertIn('100', output)
+        self.assertIn('600', output)
+
     def test_bridge_mdb(self):
         copy_unit_to_networkd_unit_path('11-dummy.netdev', '26-bridge-mdb-slave.network',
                                         '26-bridge.netdev', '26-bridge-mdb-master.network')