platform: merge branch 'th/platform-nl-extack-msg'

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1543

11 files changed, 279 insertions, 173 deletions

diff --git a/src/core/nm-netns.c b/src/core/nm-netns.c
index 12ca850898..dfdaaa06c7 100644
--- a/src/core/nm-netns.c
+++ b/src/core/nm-netns.c
@@ -815,7 +815,7 @@ nm_netns_ip_route_ecmp_commit(NMNetns    *self,
         if (changed || is_reapply) {
             _LOGT("ecmp-route: multi-hop %s",
                   nmp_object_to_string(route_obj, NMP_OBJECT_TO_STRING_PUBLIC, sbuf, sizeof(sbuf)));
-            nm_platform_ip_route_add(priv->platform, NMP_NLM_FLAG_APPEND, route_obj);
+            nm_platform_ip_route_add(priv->platform, NMP_NLM_FLAG_APPEND, route_obj, NULL);
         }
     }
 }
diff --git a/src/core/platform/nm-fake-platform.c b/src/core/platform/nm-fake-platform.c
index c92d9aef56..c5ecd90ddf 100644
--- a/src/core/platform/nm-fake-platform.c
+++ b/src/core/platform/nm-fake-platform.c
@@ -102,7 +102,9 @@ static gboolean ip6_address_add(NMPlatform     *platform,
                                 struct in6_addr peer_addr,
                                 guint32         lifetime,
                                 guint32         preferred,
-                                guint           flags);
+                                guint           flags,
+                                char          **out_extack_msg);
+
 static gboolean
 ip6_address_delete(NMPlatform *platform, int ifindex, struct in6_addr addr, guint8 plen);
 
@@ -542,7 +544,7 @@ link_changed(NMPlatform         *platform,
     nm_platform_cache_update_emit_signal(platform, cache_op, obj_old, device->obj);
 
     if (!IN6_IS_ADDR_UNSPECIFIED(&device->ip6_lladdr)) {
-        if (device->obj->link.connected)
+        if (device->obj->link.connected) {
             ip6_address_add(platform,
                             device->obj->link.ifindex,
                             device->ip6_lladdr,
@@ -550,8 +552,9 @@ link_changed(NMPlatform         *platform,
                             in6addr_any,
                             NM_PLATFORM_LIFETIME_PERMANENT,
                             NM_PLATFORM_LIFETIME_PERMANENT,
-                            0);
-        else
+                            0,
+                            NULL);
+        } else
             ip6_address_delete(platform, device->obj->link.ifindex, device->ip6_lladdr, 64);
     }
 
@@ -865,7 +868,10 @@ mesh_set_ssid(NMPlatform *platform, int ifindex, const guint8 *ssid, gsize len)
 /*****************************************************************************/
 
 static gboolean
-ipx_address_add(NMPlatform *platform, int addr_family, const NMPlatformObject *address)
+ipx_address_add(NMPlatform             *platform,
+                int                     addr_family,
+                const NMPlatformObject *address,
+                char                  **out_extack_msg)
 {
     nm_auto_nmpobj NMPObject       *obj = NULL;
     NMPCacheOpsType                 cache_op;
@@ -874,6 +880,7 @@ ipx_address_add(NMPlatform *platform, int addr_family, const NMPlatformObject *a
     NMPCache                       *cache   = nm_platform_get_cache(platform);
 
     g_assert(NM_IN_SET(addr_family, AF_INET, AF_INET6));
+    g_assert(!out_extack_msg || !*out_extack_msg);
 
     obj = nmp_object_new(addr_family == AF_INET ? NMP_OBJECT_TYPE_IP4_ADDRESS
                                                 : NMP_OBJECT_TYPE_IP6_ADDRESS,
@@ -894,7 +901,8 @@ ip4_address_add(NMPlatform *platform,
                 guint32     lifetime,
                 guint32     preferred,
                 guint32     flags,
-                const char *label)
+                const char *label,
+                char      **out_extack_msg)
 {
     NMPlatformIP4Address address;
 
@@ -914,7 +922,7 @@ ip4_address_add(NMPlatform *platform,
     if (label)
         g_strlcpy(address.label, label, sizeof(address.label));
 
-    return ipx_address_add(platform, AF_INET, (const NMPlatformObject *) &address);
+    return ipx_address_add(platform, AF_INET, (const NMPlatformObject *) &address, out_extack_msg);
 }
 
 static gboolean
@@ -925,7 +933,8 @@ ip6_address_add(NMPlatform     *platform,
                 struct in6_addr peer_addr,
                 guint32         lifetime,
                 guint32         preferred,
-                guint32         flags)
+                guint32         flags,
+                char          **out_extack_msg)
 {
     NMPlatformIP6Address address;
 
@@ -942,7 +951,7 @@ ip6_address_add(NMPlatform     *platform,
     address.preferred   = preferred;
     address.n_ifa_flags = flags;
 
-    return ipx_address_add(platform, AF_INET6, (const NMPlatformObject *) &address);
+    return ipx_address_add(platform, AF_INET6, (const NMPlatformObject *) &address, out_extack_msg);
 }
 
 static gboolean
@@ -1092,7 +1101,7 @@ object_delete(NMPlatform *platform, const NMPObject *obj)
 }
 
 static int
-ip_route_add(NMPlatform *platform, NMPNlmFlags flags, NMPObject *obj_stack)
+ip_route_add(NMPlatform *platform, NMPNlmFlags flags, NMPObject *obj_stack, char **out_extack_msg)
 {
     NMDedupMultiIter                iter;
     nm_auto_nmpobj NMPObject       *obj = NULL;
@@ -1114,6 +1123,7 @@ ip_route_add(NMPlatform *platform, NMPNlmFlags flags, NMPObject *obj_stack)
     g_assert(NM_IN_SET(NMP_OBJECT_GET_TYPE(obj_stack),
                        NMP_OBJECT_TYPE_IP4_ROUTE,
                        NMP_OBJECT_TYPE_IP6_ROUTE));
+    g_assert(!out_extack_msg || !*out_extack_msg);
 
     addr_family = NMP_OBJECT_GET_ADDR_FAMILY(obj_stack);
 
diff --git a/src/core/platform/tests/test-cleanup.c b/src/core/platform/tests/test-cleanup.c
index 139a028001..c643e71c4a 100644
--- a/src/core/platform/tests/test-cleanup.c
+++ b/src/core/platform/tests/test-cleanup.c
@@ -77,6 +77,7 @@ test_cleanup_internal(void)
                                          lifetime,
                                          preferred,
                                          0,
+                                         NULL,
                                          NULL));
     g_assert(nm_platform_ip6_address_add(NM_PLATFORM_GET,
                                          ifindex,
@@ -85,7 +86,8 @@ test_cleanup_internal(void)
                                          in6addr_any,
                                          lifetime,
                                          preferred,
-                                         flags));
+                                         flags,
+                                         NULL));
     nmtstp_ip4_route_add(NM_PLATFORM_GET,
                          ifindex,
                          NM_IP_CONFIG_SOURCE_USER,
diff --git a/src/core/platform/tests/test-common.c b/src/core/platform/tests/test-common.c
index a37982fc69..5a39d3aaf7 100644
--- a/src/core/platform/tests/test-common.c
+++ b/src/core/platform/tests/test-common.c
@@ -1809,7 +1809,8 @@ _ip_address_add(NMPlatform     *platform,
                                                   lifetime,
                                                   preferred,
                                                   flags,
-                                                  label);
+                                                  label,
+                                                  NULL);
         } else {
             g_assert(label == NULL);
             success = nm_platform_ip6_address_add(platform,
@@ -1819,7 +1820,8 @@ _ip_address_add(NMPlatform     *platform,
                                                   peer_address->addr6,
                                                   lifetime,
                                                   preferred,
-                                                  flags);
+                                                  flags,
+                                                  NULL);
         }
         g_assert(success);
     }
diff --git a/src/core/platform/tests/test-route.c b/src/core/platform/tests/test-route.c
index bd8fdc271c..9aa21a9ac6 100644
--- a/src/core/platform/tests/test-route.c
+++ b/src/core/platform/tests/test-route.c
@@ -421,7 +421,8 @@ test_ip6_route(void)
                                          in6addr_any,
                                          NM_PLATFORM_LIFETIME_PERMANENT,
                                          NM_PLATFORM_LIFETIME_PERMANENT,
-                                         0));
+                                         0,
+                                         NULL));
     accept_signals(route_added, 0, 3);
 
     _wait_for_ipv6_addr_non_tentative(NM_PLATFORM_GET, 200, ifindex, 1, &pref_src);
@@ -706,7 +707,8 @@ test_ip4_route_options(gconstpointer test_data)
                                              a->lifetime,
                                              a->preferred,
                                              a->n_ifa_flags,
-                                             a->label));
+                                             a->label,
+                                             NULL));
         if (a->peer_address == a->address)
             _wait_for_ipv4_addr_device_route(NM_PLATFORM_GET, 200, a->ifindex, a->address, a->plen);
     }
@@ -878,7 +880,8 @@ test_ip6_route_options(gconstpointer test_data)
                                              addr[i].peer_address,
                                              addr[i].lifetime,
                                              addr[i].preferred,
-                                             addr[i].n_ifa_flags));
+                                             addr[i].n_ifa_flags,
+                                             NULL));
     }
     _wait_for_ipv6_addr_non_tentative(NM_PLATFORM_GET, 400, IFINDEX, addr_n, addr_in6);
 
diff --git a/src/libnm-platform/nm-linux-platform.c b/src/libnm-platform/nm-linux-platform.c
index 30ad1275d8..cf47fb35ee 100644
--- a/src/libnm-platform/nm-linux-platform.c
+++ b/src/libnm-platform/nm-linux-platform.c
@@ -465,7 +465,7 @@ typedef enum _nm_packed {
 
 typedef struct {
     WaitForNlResponseResult *out_seq_result;
-    char                   **out_errmsg;
+    char                   **out_extack_msg;
     union {
         int        *out_refresh_all_in_progress;
         NMPObject **out_route_get;
@@ -482,9 +482,6 @@ typedef struct {
 typedef struct {
     guint32 nlh_seq_next;
     guint32 nlh_seq_last_seen;
-#if NM_MORE_LOGGING
-    guint32 nlh_seq_last_handled;
-#endif
 } NetlinkProtocolPrivData;
 
 typedef struct {
@@ -709,7 +706,7 @@ wait_for_nl_response_to_nmerr(WaitForNlResponseResult seq_result)
 
 static const char *
 wait_for_nl_response_to_string(WaitForNlResponseResult seq_result,
-                               const char             *errmsg,
+                               const char             *extack_msg,
                                char                   *buf,
                                gsize                   buf_size)
 {
@@ -735,8 +732,8 @@ wait_for_nl_response_to_string(WaitForNlResponseResult seq_result,
                              "failure %d (%s%s%s)",
                              -((int) seq_result),
                              nm_strerror_native(-((int) seq_result)),
-                             errmsg ? " - " : "",
-                             errmsg ?: "");
+                             extack_msg ? " - " : "",
+                             extack_msg ?: "");
         } else
             nm_strbuf_append(&buf, &buf_size, "internal failure %d", (int) seq_result);
         break;
@@ -6994,7 +6991,7 @@ delayed_action_schedule_WAIT_FOR_RESPONSE(NMPlatform                        *pla
                                           NMPNetlinkProtocol                 netlink_protocol,
                                           guint32                            seq_number,
                                           WaitForNlResponseResult           *out_seq_result,
-                                          char                             **out_errmsg,
+                                          char                             **out_extack_msg,
                                           DelayedActionWaitForNlResponseType response_type,
                                           gpointer                           response_out_data)
 {
@@ -7003,7 +7000,7 @@ delayed_action_schedule_WAIT_FOR_RESPONSE(NMPlatform                        *pla
         .timeout_abs_nsec =
             nm_utils_get_monotonic_timestamp_nsec() + (200 * (NM_UTILS_NSEC_PER_SEC / 1000)),
         .out_seq_result    = out_seq_result,
-        .out_errmsg        = out_errmsg,
+        .out_extack_msg    = out_extack_msg,
         .response_type     = response_type,
         .response.out_data = response_out_data,
     };
@@ -7362,7 +7359,7 @@ static int
 _nl_send_nlmsghdr(NMPlatform                        *platform,
                   struct nlmsghdr                   *nlhdr,
                   WaitForNlResponseResult           *out_seq_result,
-                  char                             **out_errmsg,
+                  char                             **out_extack_msg,
                   DelayedActionWaitForNlResponseType response_type,
                   gpointer                           response_out_data)
 {
@@ -7410,7 +7407,7 @@ again:
                                               NMP_NETLINK_ROUTE,
                                               seq,
                                               out_seq_result,
-                                              out_errmsg,
+                                              out_extack_msg,
                                               response_type,
                                               response_out_data);
     return 0;
@@ -7421,7 +7418,7 @@ _netlink_send_nlmsg(NMPlatform                        *platform,
                     NMPNetlinkProtocol                 netlink_protocol,
                     struct nl_msg                     *nlmsg,
                     WaitForNlResponseResult           *out_seq_result,
-                    char                             **out_errmsg,
+                    char                             **out_extack_msg,
                     DelayedActionWaitForNlResponseType response_type,
                     gpointer                           response_out_data)
 {
@@ -7444,7 +7441,7 @@ _netlink_send_nlmsg(NMPlatform                        *platform,
                                               netlink_protocol,
                                               seq,
                                               out_seq_result,
-                                              out_errmsg,
+                                              out_extack_msg,
                                               response_type,
                                               response_out_data);
     return 0;
@@ -7454,13 +7451,13 @@ static int
 _netlink_send_nlmsg_rtnl(NMPlatform              *platform,
                          struct nl_msg           *nlmsg,
                          WaitForNlResponseResult *out_seq_result,
-                         char                   **out_errmsg)
+                         char                   **out_extack_msg)
 {
     return _netlink_send_nlmsg(platform,
                                NMP_NETLINK_ROUTE,
                                nlmsg,
                                out_seq_result,
-                               out_errmsg,
+                               out_extack_msg,
                                DELAYED_ACTION_RESPONSE_TYPE_VOID,
                                NULL);
 }
@@ -7731,7 +7728,7 @@ event_seq_check(NMPlatform             *platform,
                 NMPNetlinkProtocol      netlink_protocol,
                 guint32                 seq_number,
                 WaitForNlResponseResult seq_result,
-                const char             *msg)
+                const char             *extack_msg)
 {
     NMLinuxPlatformPrivate *priv = NM_LINUX_PLATFORM_GET_PRIVATE(platform);
     guint                   i;
@@ -7742,7 +7739,7 @@ event_seq_check(NMPlatform             *platform,
     if (!NM_FLAGS_ANY(
             priv->delayed_action.flags,
             nmp_netlink_protocol_info(netlink_protocol)->delayed_action_type_wait_for_response))
-        goto out;
+        return;
 
     nm_assert(priv->delayed_action.list_wait_for_response_x[netlink_protocol]->len > 0);
 
@@ -7750,30 +7747,23 @@ event_seq_check(NMPlatform             *platform,
         DelayedActionWaitForNlResponseData *data =
             delayed_action_get_list_wait_for_resonse(priv, netlink_protocol, i);
 
-        if (data->seq_number == seq_number) {
-            /* We potentially receive many parts partial responses for the same sequence number.
-                 * Thus, we only remember the result, and collect it later. */
-            if (data->seq_result < 0) {
-                /* we already saw an error for this sequence number.
-                     * Preserve it. */
-            } else if (seq_result != WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_UNKNOWN
-                       || data->seq_result == WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN)
-                data->seq_result = seq_result;
-            if (data->out_errmsg && !*data->out_errmsg)
-                *data->out_errmsg = g_strdup(msg);
-            return;
-        }
-    }
+        if (data->seq_number != seq_number)
+            continue;
 
-out:
+        /* We potentially receive many parts partial responses for the same sequence number.
+         * Thus, we only remember the result, and collect it later. */
+        if (data->seq_result < 0) {
+            /* we already saw an error for this sequence number.
+             * Preserve it. */
+        } else if (seq_result != WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_UNKNOWN
+                   || data->seq_result == WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN)
+            data->seq_result = seq_result;
 
-#if NM_MORE_LOGGING
-    if (seq_number != priv->proto_data_x[netlink_protocol].nlh_seq_last_handled)
-        _LOGt("netlink: recvmsg: unwaited sequence number %u", seq_number);
-    priv->proto_data_x[netlink_protocol].nlh_seq_last_handled = seq_number;
-#else
-    (void) 0;
-#endif
+        if (extack_msg && data->out_extack_msg && !*data->out_extack_msg)
+            *data->out_extack_msg = g_strdup(extack_msg);
+
+        return;
+    }
 }
 
 static void
@@ -8011,14 +8001,14 @@ do_add_link_with_lookup(NMPlatform            *platform,
 {
     const NMPObject        *obj        = NULL;
     WaitForNlResponseResult seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char           *errmsg     = NULL;
+    gs_free char           *extack_msg = NULL;
     int                     nle;
     char                    s_buf[256];
     NMPCache               *cache = nm_platform_get_cache(platform);
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &extack_msg);
     if (nle < 0) {
         _LOGE("do-add-link[%s/%s]: failed sending netlink request \"%s\" (%d)",
               name,
@@ -8037,7 +8027,7 @@ do_add_link_with_lookup(NMPlatform            *platform,
            "do-add-link[%s/%s]: %s",
            name,
            nm_link_type_to_string(link_type),
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)));
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)));
 
     if (out_link) {
         obj       = nmp_cache_lookup_link_full(cache, 0, name, FALSE, link_type, NULL, NULL);
@@ -8051,14 +8041,16 @@ static int
 do_add_addrroute(NMPlatform      *platform,
                  const NMPObject *obj_id,
                  struct nl_msg   *nlmsg,
-                 gboolean         suppress_netlink_failure)
+                 gboolean         suppress_netlink_failure,
+                 char           **out_extack_msg)
 {
     char                    sbuf1[NM_UTILS_TO_STRING_BUFFER_SIZE];
     WaitForNlResponseResult seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char           *errmsg     = NULL;
+    gs_free char           *extack_msg = NULL;
     int                     nle;
     char                    s_buf[256];
 
+    nm_assert(!out_extack_msg || !*out_extack_msg);
     nm_assert(NM_IN_SET(NMP_OBJECT_GET_TYPE(obj_id),
                         NMP_OBJECT_TYPE_IP4_ADDRESS,
                         NMP_OBJECT_TYPE_IP6_ADDRESS,
@@ -8067,13 +8059,14 @@ do_add_addrroute(NMPlatform      *platform,
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &extack_msg);
     if (nle < 0) {
         _LOGE("do-add-%s[%s]: failure sending netlink request \"%s\" (%d)",
               NMP_OBJECT_GET_CLASS(obj_id)->obj_type_name,
               nmp_object_to_string(obj_id, NMP_OBJECT_TO_STRING_ID, sbuf1, sizeof(sbuf1)),
               nm_strerror(nle),
               -nle);
+        NM_SET_OUT(out_extack_msg, g_steal_pointer(&extack_msg));
         return -NME_PL_NETLINK;
     }
 
@@ -8088,7 +8081,7 @@ do_add_addrroute(NMPlatform      *platform,
            "do-add-%s[%s]: %s",
            NMP_OBJECT_GET_CLASS(obj_id)->obj_type_name,
            nmp_object_to_string(obj_id, NMP_OBJECT_TO_STRING_ID, sbuf1, sizeof(sbuf1)),
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)));
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)));
 
     if (NMP_OBJECT_GET_TYPE(obj_id) == NMP_OBJECT_TYPE_IP6_ADDRESS) {
         /* In rare cases, the object is not yet ready as we received the ACK from
@@ -8110,7 +8103,7 @@ do_delete_object(NMPlatform *platform, const NMPObject *obj_id, struct nl_msg *n
 {
     char                    sbuf1[NM_UTILS_TO_STRING_BUFFER_SIZE];
     WaitForNlResponseResult seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char           *errmsg     = NULL;
+    gs_free char           *extack_msg = NULL;
     int                     nle;
     char                    s_buf[256];
     gboolean                success;
@@ -8118,7 +8111,7 @@ do_delete_object(NMPlatform *platform, const NMPObject *obj_id, struct nl_msg *n
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &extack_msg);
     if (nle < 0) {
         _LOGE("do-delete-%s[%s]: failure sending netlink request \"%s\" (%d)",
               NMP_OBJECT_GET_CLASS(obj_id)->obj_type_name,
@@ -8155,7 +8148,7 @@ do_delete_object(NMPlatform *platform, const NMPObject *obj_id, struct nl_msg *n
            "do-delete-%s[%s]: %s%s",
            NMP_OBJECT_GET_CLASS(obj_id)->obj_type_name,
            nmp_object_to_string(obj_id, NMP_OBJECT_TO_STRING_ID, sbuf1, sizeof(sbuf1)),
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)),
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)),
            log_detail);
 
     if (NM_IN_SET(NMP_OBJECT_GET_TYPE(obj_id),
@@ -8186,7 +8179,7 @@ do_change_link(NMPlatform           *platform,
     nm_auto_pop_netns NMPNetns *netns = NULL;
     int                         nle;
     WaitForNlResponseResult     seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char               *errmsg     = NULL;
+    gs_free char               *extack_msg = NULL;
     char                        s_buf[256];
     int                         result;
     NMLogLevel                  log_level;
@@ -8207,7 +8200,7 @@ retry:
     log_detail = "";
     nm_clear_g_free(&log_detail_free);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, nlmsg, &seq_result, &extack_msg);
     if (nle < 0) {
         log_level = LOGL_ERR;
         log_detail_free =
@@ -8267,7 +8260,7 @@ out:
     _NMLOG(log_level,
            "do-change-link[%d]: %s%s",
            ifindex,
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)),
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)),
            log_detail);
 
     if (result == -EAGAIN)
@@ -9499,7 +9492,8 @@ ip4_address_add(NMPlatform *platform,
                 guint32     lifetime,
                 guint32     preferred,
                 guint32     flags,
-                const char *label)
+                const char *label,
+                char      **out_extack_msg)
 {
     NMPObject                    obj_id;
     nm_auto_nlmsg struct nl_msg *nlmsg = NULL;
@@ -9519,7 +9513,7 @@ ip4_address_add(NMPlatform *platform,
                                 label);
 
     nmp_object_stackinit_id_ip4_address(&obj_id, ifindex, addr, plen, peer_addr);
-    return (do_add_addrroute(platform, &obj_id, nlmsg, FALSE) >= 0);
+    return (do_add_addrroute(platform, &obj_id, nlmsg, FALSE, out_extack_msg) >= 0);
 }
 
 static gboolean
@@ -9530,7 +9524,8 @@ ip6_address_add(NMPlatform     *platform,
                 struct in6_addr peer_addr,
                 guint32         lifetime,
                 guint32         preferred,
-                guint32         flags)
+                guint32         flags,
+                char          **out_extack_msg)
 {
     NMPObject                    obj_id;
     nm_auto_nlmsg struct nl_msg *nlmsg = NULL;
@@ -9550,7 +9545,7 @@ ip6_address_add(NMPlatform     *platform,
                                 NULL);
 
     nmp_object_stackinit_id_ip6_address(&obj_id, ifindex, &addr);
-    return (do_add_addrroute(platform, &obj_id, nlmsg, FALSE) >= 0);
+    return (do_add_addrroute(platform, &obj_id, nlmsg, FALSE, out_extack_msg) >= 0);
 }
 
 static gboolean
@@ -9612,7 +9607,7 @@ ip6_address_delete(NMPlatform *platform, int ifindex, struct in6_addr addr, guin
 /*****************************************************************************/
 
 static int
-ip_route_add(NMPlatform *platform, NMPNlmFlags flags, NMPObject *obj_stack)
+ip_route_add(NMPlatform *platform, NMPNlmFlags flags, NMPObject *obj_stack, char **out_extack_msg)
 {
     nm_auto_nlmsg struct nl_msg *nlmsg = NULL;
 
@@ -9622,7 +9617,8 @@ ip_route_add(NMPlatform *platform, NMPNlmFlags flags, NMPObject *obj_stack)
     return do_add_addrroute(platform,
                             obj_stack,
                             nlmsg,
-                            NM_FLAGS_HAS(flags, NMP_NLM_FLAG_SUPPRESS_NETLINK_FAILURE));
+                            NM_FLAGS_HAS(flags, NMP_NLM_FLAG_SUPPRESS_NETLINK_FAILURE),
+                            out_extack_msg);
 }
 
 static gboolean
@@ -9751,7 +9747,7 @@ routing_rule_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformRoutin
 {
     WaitForNlResponseResult      seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
     nm_auto_nlmsg struct nl_msg *msg        = NULL;
-    gs_free char                *errmsg     = NULL;
+    gs_free char                *extack_msg = NULL;
     char                         s_buf[256];
     int                          nle;
 
@@ -9759,7 +9755,7 @@ routing_rule_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformRoutin
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &extack_msg);
     if (nle < 0) {
         _LOGE("do-add-rule: failed sending netlink request \"%s\" (%d)", nm_strerror(nle), -nle);
         return -NME_PL_NETLINK;
@@ -9771,7 +9767,7 @@ routing_rule_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformRoutin
 
     _NMLOG(seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK ? LOGL_DEBUG : LOGL_WARN,
            "do-add-rule: %s",
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)));
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)));
 
     if (seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK)
         return 0;
@@ -9786,7 +9782,7 @@ static int
 qdisc_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformQdisc *qdisc)
 {
     WaitForNlResponseResult      seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char                *errmsg     = NULL;
+    gs_free char                *extack_msg = NULL;
     int                          nle;
     char                         s_buf[256];
     nm_auto_nlmsg struct nl_msg *msg = NULL;
@@ -9798,7 +9794,7 @@ qdisc_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformQdisc *qdisc)
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &extack_msg);
     if (nle < 0) {
         _LOGE("do-add-qdisc: failed sending netlink request \"%s\" (%d)", nm_strerror(nle), -nle);
         return -NME_PL_NETLINK;
@@ -9810,7 +9806,7 @@ qdisc_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformQdisc *qdisc)
 
     _NMLOG(seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK ? LOGL_DEBUG : LOGL_WARN,
            "do-add-qdisc: %s",
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)));
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)));
 
     if (seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK)
         return 0;
@@ -9827,7 +9823,7 @@ tc_delete(NMPlatform *platform,
           gboolean    log_error)
 {
     WaitForNlResponseResult      seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char                *errmsg     = NULL;
+    gs_free char                *extack_msg = NULL;
     int                          nle;
     char                         s_buf[256];
     const char                  *log_tag;
@@ -9856,7 +9852,7 @@ tc_delete(NMPlatform *platform,
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &extack_msg);
     if (nle < 0) {
         _NMLOG(log_error ? LOGL_ERR : LOGL_DEBUG,
                "%s: failed sending netlink request \"%s\" (%d)",
@@ -9874,7 +9870,7 @@ tc_delete(NMPlatform *platform,
                                                                                  : LOGL_WARN,
            "%s: %s",
            log_tag,
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)));
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)));
 
     if (seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK)
         return 0;
@@ -9896,7 +9892,7 @@ static int
 tfilter_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformTfilter *tfilter)
 {
     WaitForNlResponseResult      seq_result = WAIT_FOR_NL_RESPONSE_RESULT_UNKNOWN;
-    gs_free char                *errmsg     = NULL;
+    gs_free char                *extack_msg = NULL;
     int                          nle;
     char                         s_buf[256];
     nm_auto_nlmsg struct nl_msg *msg = NULL;
@@ -9908,7 +9904,7 @@ tfilter_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformTfilter *tf
 
     event_handler_read_netlink(platform, NMP_NETLINK_ROUTE, FALSE);
 
-    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &errmsg);
+    nle = _netlink_send_nlmsg_rtnl(platform, msg, &seq_result, &extack_msg);
     if (nle < 0) {
         _LOGE("do-add-tfilter: failed sending netlink request \"%s\" (%d)", nm_strerror(nle), -nle);
         return -NME_PL_NETLINK;
@@ -9920,7 +9916,7 @@ tfilter_add(NMPlatform *platform, NMPNlmFlags flags, const NMPlatformTfilter *tf
 
     _NMLOG(seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK ? LOGL_DEBUG : LOGL_WARN,
            "do-add-tfilter: %s",
-           wait_for_nl_response_to_string(seq_result, errmsg, s_buf, sizeof(s_buf)));
+           wait_for_nl_response_to_string(seq_result, extack_msg, s_buf, sizeof(s_buf)));
 
     if (seq_result == WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK)
         return 0;
@@ -10176,9 +10172,16 @@ continue_reading:
             int errsv;
 
             errsv = nlmsg_parse_error(msg.nm_nlh, &extack_msg);
-            if (errsv == 0)
+            if (errsv == 0) {
                 seq_result = WAIT_FOR_NL_RESPONSE_RESULT_RESPONSE_OK;
-            else {
+                if (extack_msg) {
+                    _LOGD("%s: recvmsg: warning message from kernel: %s%s%s for request %d",
+                          log_prefix,
+                          NM_PRINT_FMT_QUOTE_STRING(extack_msg),
+                          msg.nm_nlh->nlmsg_seq);
+                    extack_msg = NULL;
+                }
+            } else {
                 _LOGD("%s: recvmsg: error message from kernel: %s (%d)%s%s%s for request %d",
                       log_prefix,
                       nm_strerror(errsv),
@@ -10636,9 +10639,10 @@ mptcp_addr_update(NMPlatform *platform, NMOptionBool add, const NMPlatformMptcpA
         return nle;
     }
 
-    _LOGT("mptcp: %s address %s: success",
+    _LOGT("mptcp: %s address %s: success%s%s%s",
           cmd_str,
-          nm_platform_mptcp_addr_to_string(addr, sbuf, sizeof(sbuf)));
+          nm_platform_mptcp_addr_to_string(addr, sbuf, sizeof(sbuf)),
+          NM_PRINT_FMT_QUOTED(extack_msg[0] != '\0', " Warning: \"", extack_msg, "\"", ""));
 
     return 0;
 
diff --git a/src/libnm-platform/nm-netlink.c b/src/libnm-platform/nm-netlink.c
index fc70422642..e95768465a 100644
--- a/src/libnm-platform/nm-netlink.c
+++ b/src/libnm-platform/nm-netlink.c
@@ -313,9 +313,6 @@ nlmsg_parse_error(const struct nlmsghdr *nlh, const char **out_extack_msg)
 
     e = nlmsg_data(nlh);
 
-    if (!e->error)
-        return 0;
-
     if (NM_FLAGS_HAS(nlh->nlmsg_flags, NLM_F_ACK_TLVS) && out_extack_msg
         && nlh->nlmsg_len >= sizeof(*e) + e->msg.nlmsg_len) {
         static const struct nla_policy policy[] = {
@@ -328,11 +325,19 @@ nlmsg_parse_error(const struct nlmsghdr *nlh, const char **out_extack_msg)
         tlvs = NM_CAST_ALIGN(struct nlattr,
                              (((char *) e) + sizeof(*e) + e->msg.nlmsg_len - NLMSG_HDRLEN));
         if (nla_parse_arr(tb, tlvs, nlh->nlmsg_len - sizeof(*e) - e->msg.nlmsg_len, policy) >= 0) {
-            if (tb[NLMSGERR_ATTR_MSG])
-                *out_extack_msg = nla_get_string(tb[NLMSGERR_ATTR_MSG]);
+            if (tb[NLMSGERR_ATTR_MSG]) {
+                const char *s;
+
+                s = nla_get_string(tb[NLMSGERR_ATTR_MSG]);
+                if (s[0] != '\0')
+                    *out_extack_msg = s;
+            }
         }
     }
 
+    if (!e->error)
+        return 0;
+
     return -nm_errno_from_native(e->error);
 }
 
@@ -488,44 +493,52 @@ nlmsg_put(struct nl_msg *n,
 }
 
 size_t
-nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
+_nla_strlcpy_full(char *dst, const struct nlattr *nla, size_t dstsize, gboolean wipe_remainder)
 {
-    const char *src;
+    const char *src = NULL;
     size_t      srclen;
-    size_t      len;
-
-    /* - Always writes @dstsize bytes to @dst
-     * - Copies the first non-NUL characters to @dst.
-     *   Any characters after the first NUL bytes in @nla are ignored.
-     * - If the string @nla is longer than @dstsize, the string
-     *   gets truncated. @dst will always be NUL terminated. */
-
-    if (G_UNLIKELY(dstsize <= 1)) {
-        if (dstsize == 1)
-            dst[0] = '\0';
-        if (nla && (srclen = nla_len(nla)) > 0)
-            return strnlen(nla_data(nla), srclen);
-        return 0;
-    }
+    size_t      cpylen;
+
+    /* Behaves like strlcpy():
+     *
+     * - returns the length of the string in nla (how much it wanted to copy).
+     * - will always NUL terminate dst (unless dstsize is zero).
+     * - if @wipe_remainder, the remaining bytes after the string are set to NUL,
+     *   similar to what strncpy() would do. Otherwise the bytes are undefined.
+     * - nla is not required to contain a NUL terminated string (unlike nla_get_string()).
+     * - the function copies the bytes up to the first NUL character in nla.
+     *   any remainder in nla is ignored.
+     * - nla may be NULL, which is treated the same as an empty string (copying zero bytes).
+     */
 
-    nm_assert(dst);
+    nm_assert(dstsize == 0 || dst);
 
     if (nla) {
         srclen = nla_len(nla);
         if (srclen > 0) {
             src    = nla_data(nla);
             srclen = strnlen(src, srclen);
-            if (srclen > 0) {
-                len = NM_MIN(dstsize - 1, srclen);
-                memcpy(dst, src, len);
-                memset(&dst[len], 0, dstsize - len);
-                return srclen;
-            }
         }
+    } else
+        srclen = 0;
+
+    if (dstsize == 0) {
+        /* we cannot NUL terminate. This is potentially dangerous, maybe
+         * we should assert against this case. */
+        return srclen;
     }
 
-    memset(dst, 0, dstsize);
-    return 0;
+    cpylen = NM_MIN(dstsize - 1u, srclen);
+
+    nm_memcpy(dst, src, cpylen);
+
+    if (wipe_remainder) {
+        /* like strncpy() would do, wipe the rest. */
+        memset(&dst[cpylen], 0, dstsize - cpylen);
+    } else
+        dst[cpylen] = '\0';
+
+    return srclen;
 }
 
 size_t
diff --git a/src/libnm-platform/nm-netlink.h b/src/libnm-platform/nm-netlink.h
index cdb8a81c32..117525f944 100644
--- a/src/libnm-platform/nm-netlink.h
+++ b/src/libnm-platform/nm-netlink.h
@@ -238,10 +238,36 @@ nla_get_be64(const struct nlattr *nla)
 static inline char *
 nla_get_string(const struct nlattr *nla)
 {
-    return nla_data(nla);
+    char *s;
+
+    /* nla_get_string() requires that nla contains a NUL terminated string.
+     * It cannot return NULL. Only use it with attributes that validate as NLA_STRING. */
+
+    nm_assert(nla_len(nla) > 0);
+
+    s = nla_data(nla);
+
+    nm_assert(memchr(s, 0, nla_len(nla)));
+
+    return s;
 }
 
-size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize);
+size_t
+_nla_strlcpy_full(char *dst, const struct nlattr *nla, size_t dstsize, gboolean wipe_remainder);
+
+static inline size_t
+nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
+{
+    return _nla_strlcpy_full(dst, nla, dstsize, FALSE);
+}
+
+static inline size_t
+nla_strlcpy_wipe(char *dst, const struct nlattr *nla, size_t dstsize)
+{
+    /* Behaves exactly like nla_strlcpy(), but (similar to strncpy()) it fills the
+     * remaining @dstsize bytes with NUL. */
+    return _nla_strlcpy_full(dst, nla, dstsize, TRUE);
+}
 
 size_t nla_memcpy(void *dst, const struct nlattr *nla, size_t dstsize);
 
diff --git a/src/libnm-platform/nm-platform.c b/src/libnm-platform/nm-platform.c
index c80d964851..b1ac3132c0 100644
--- a/src/libnm-platform/nm-platform.c
+++ b/src/libnm-platform/nm-platform.c
@@ -3559,7 +3559,8 @@ nm_platform_ip4_address_add(NMPlatform *self,
                             guint32     lifetime,
                             guint32     preferred,
                             guint32     flags,
-                            const char *label)
+                            const char *label,
+                            char      **out_extack_msg)
 {
     _CHECK_SELF(self, klass, FALSE);
 
@@ -3569,6 +3570,7 @@ nm_platform_ip4_address_add(NMPlatform *self,
     g_return_val_if_fail(preferred <= lifetime, FALSE);
     g_return_val_if_fail(!label || strlen(label) < sizeof(((NMPlatformIP4Address *) NULL)->label),
                          FALSE);
+    nm_assert(!out_extack_msg || !*out_extack_msg);
 
     if (_LOGD_ENABLED()) {
         char                 sbuf[NM_UTILS_TO_STRING_BUFFER_SIZE];
@@ -3601,7 +3603,8 @@ nm_platform_ip4_address_add(NMPlatform *self,
                                   lifetime,
                                   preferred,
                                   flags,
-                                  label);
+                                  label,
+                                  out_extack_msg);
 }
 
 gboolean
@@ -3612,7 +3615,8 @@ nm_platform_ip6_address_add(NMPlatform     *self,
                             struct in6_addr peer_address,
                             guint32         lifetime,
                             guint32         preferred,
-                            guint32         flags)
+                            guint32         flags,
+                            char          **out_extack_msg)
 {
     _CHECK_SELF(self, klass, FALSE);
 
@@ -3620,6 +3624,7 @@ nm_platform_ip6_address_add(NMPlatform     *self,
     g_return_val_if_fail(plen <= 128, FALSE);
     g_return_val_if_fail(lifetime > 0, FALSE);
     g_return_val_if_fail(preferred <= lifetime, FALSE);
+    nm_assert(!out_extack_msg || !*out_extack_msg);
 
     if (_LOGD_ENABLED()) {
         char                 sbuf[NM_UTILS_TO_STRING_BUFFER_SIZE];
@@ -3640,8 +3645,15 @@ nm_platform_ip6_address_add(NMPlatform     *self,
 
     nm_platform_ip6_dadfailed_set(self, ifindex, &address, FALSE);
 
-    return klass
-        ->ip6_address_add(self, ifindex, address, plen, peer_address, lifetime, preferred, flags);
+    return klass->ip6_address_add(self,
+                                  ifindex,
+                                  address,
+                                  plen,
+                                  peer_address,
+                                  lifetime,
+                                  preferred,
+                                  flags,
+                                  out_extack_msg);
 }
 
 gboolean
@@ -4464,7 +4476,8 @@ next_plat:;
                     NM_FLAGS_HAS(flags, NMP_IP_ADDRESS_SYNC_FLAGS_WITH_NOPREFIXROUTE)
                         ? IFA_F_NOPREFIXROUTE
                         : 0,
-                    known_address->a4.label))
+                    known_address->a4.label,
+                    NULL))
                 success = FALSE;
         } else {
             if (!nm_platform_ip6_address_add(
@@ -4478,7 +4491,8 @@ next_plat:;
                     (NM_FLAGS_HAS(flags, NMP_IP_ADDRESS_SYNC_FLAGS_WITH_NOPREFIXROUTE)
                          ? IFA_F_NOPREFIXROUTE
                          : 0)
-                        | known_address->a6.n_ifa_flags))
+                        | known_address->a6.n_ifa_flags,
+                    NULL))
                 success = FALSE;
         }
     }
@@ -4520,39 +4534,50 @@ nm_platform_ip_address_flush(NMPlatform *self, int addr_family, int ifindex)
 /*****************************************************************************/
 
 static gboolean
-_err_inval_due_to_ipv6_tentative_pref_src(NMPlatform *self, const NMPObject *obj)
+_route_is_temporary_not_available(NMPlatform      *self,
+                                  int              err,
+                                  const NMPObject *obj,
+                                  const char     **out_err_reason)
 {
-    const NMPlatformIP6Route   *r;
+    const NMPlatformIPXRoute   *rx;
     const NMPlatformIP6Address *a;
 
     nm_assert(NM_IS_PLATFORM(self));
     nm_assert(NMP_OBJECT_IS_VALID(obj));
 
-    /* trying to add an IPv6 route with pref-src fails, if the address is
-     * still tentative (rh#1452684). We need to hack around that.
-     *
-     * Detect it, by guessing whether that's the case. */
-
-    if (NMP_OBJECT_GET_TYPE(obj) != NMP_OBJECT_TYPE_IP6_ROUTE)
+    if (err != -EINVAL)
         return FALSE;
 
-    r = NMP_OBJECT_CAST_IP6_ROUTE(obj);
+    rx = NMP_OBJECT_CAST_IPX_ROUTE(obj);
 
-    /* we only allow this workaround for routes added manually by the user. */
-    if (r->rt_source != NM_IP_CONFIG_SOURCE_USER)
+    if (rx->rx.rt_source != NM_IP_CONFIG_SOURCE_USER) {
+        /* we only allow this workaround for routes added manually by the user. */
         return FALSE;
+    }
 
-    if (IN6_IS_ADDR_UNSPECIFIED(&r->pref_src))
+    if (NMP_OBJECT_GET_TYPE(obj) == NMP_OBJECT_TYPE_IP4_ROUTE) {
         return FALSE;
+    } else {
+        const NMPlatformIP6Route *r = &rx->r6;
 
-    a = nm_platform_ip6_address_get(self, r->ifindex, &r->pref_src);
-    if (!a)
-        return FALSE;
-    if (!NM_FLAGS_HAS(a->n_ifa_flags, IFA_F_TENTATIVE)
-        || NM_FLAGS_HAS(a->n_ifa_flags, IFA_F_DADFAILED))
-        return FALSE;
+        /* trying to add an IPv6 route with pref-src fails, if the address is
+         * still tentative (rh#1452684). We need to hack around that.
+         *
+         * Detect it, by guessing whether that's the case. */
 
-    return TRUE;
+        if (IN6_IS_ADDR_UNSPECIFIED(&r->pref_src))
+            return FALSE;
+
+        a = nm_platform_ip6_address_get(self, r->ifindex, &r->pref_src);
+        if (!a)
+            return FALSE;
+        if (!NM_FLAGS_HAS(a->n_ifa_flags, IFA_F_TENTATIVE)
+            || NM_FLAGS_HAS(a->n_ifa_flags, IFA_F_DADFAILED))
+            return FALSE;
+
+        *out_err_reason = "tentative IPv6 src address not ready";
+        return TRUE;
+    }
 }
 
 static guint
@@ -4914,8 +4939,10 @@ nm_platform_ip_route_sync(NMPlatform *self,
 
     for (i_type = 0; routes && i_type < 2; i_type++) {
         for (i = 0; i < routes->len; i++) {
-            int      r, r2;
-            gboolean gateway_route_added = FALSE;
+            gs_free char *extack_msg          = NULL;
+            gboolean      gateway_route_added = FALSE;
+            int           r2;
+            int           r;
 
             conf_o = routes->pdata[i];
 
@@ -4975,8 +5002,11 @@ sync_route_add:
             r = nm_platform_ip_route_add(self,
                                          NMP_NLM_FLAG_APPEND
                                              | NMP_NLM_FLAG_SUPPRESS_NETLINK_FAILURE,
-                                         conf_o);
+                                         conf_o,
+                                         &extack_msg);
             if (r < 0) {
+                const char *err_reason = NULL;
+
                 if (r == -EEXIST) {
                     /* Don't fail for EEXIST. It's not clear that the existing route
                      * is identical to the one that we were about to add. However,
@@ -5015,15 +5045,15 @@ sync_route_add:
                                                 sbuf1,
                                                 sizeof(sbuf1)),
                            nm_strerror(r));
-                } else if (r == -EINVAL && out_temporary_not_available
-                           && _err_inval_due_to_ipv6_tentative_pref_src(self, conf_o)) {
-                    _LOG3D("route-sync: ignore failure to add IPv6 route with tentative IPv6 "
-                           "pref-src: %s: %s",
+                } else if (out_temporary_not_available
+                           && _route_is_temporary_not_available(self, r, conf_o, &err_reason)) {
+                    _LOG3D("route-sync: ignore temporary failure to add route (%s, %s): %s",
+                           nm_strerror(r),
+                           err_reason,
                            nmp_object_to_string(conf_o,
                                                 NMP_OBJECT_TO_STRING_PUBLIC,
                                                 sbuf1,
-                                                sizeof(sbuf1)),
-                           nm_strerror(r));
+                                                sizeof(sbuf1)));
                     if (!*out_temporary_not_available)
                         *out_temporary_not_available =
                             g_ptr_array_new_full(0, (GDestroyNotify) nmp_object_unref);
@@ -5085,7 +5115,8 @@ sync_route_add:
                     r2 = nm_platform_ip_route_add(self,
                                                   NMP_NLM_FLAG_APPEND
                                                       | NMP_NLM_FLAG_SUPPRESS_NETLINK_FAILURE,
-                                                  &oo);
+                                                  &oo,
+                                                  NULL);
 
                     if (r2 < 0) {
                         _LOG3D("route-sync: failure to add gateway IPv%c route: %s: %s",
@@ -5250,7 +5281,7 @@ nm_platform_ip_route_normalize(int addr_family, NMPlatformIPRoute *route)
 }
 
 static int
-_ip_route_add(NMPlatform *self, NMPNlmFlags flags, NMPObject *obj_stack)
+_ip_route_add(NMPlatform *self, NMPNlmFlags flags, NMPObject *obj_stack, char **out_extack_msg)
 {
     char sbuf[NM_UTILS_TO_STRING_BUFFER_SIZE];
     int  ifindex;
@@ -5266,6 +5297,7 @@ _ip_route_add(NMPlatform *self, NMPNlmFlags flags, NMPObject *obj_stack)
     nm_assert(NM_IN_SET(NMP_OBJECT_GET_TYPE(obj_stack),
                         NMP_OBJECT_TYPE_IP4_ROUTE,
                         NMP_OBJECT_TYPE_IP6_ROUTE));
+    nm_assert(!out_extack_msg || !*out_extack_msg);
 
     nm_assert(NMP_OBJECT_GET_TYPE(obj_stack) != NMP_OBJECT_TYPE_IP4_ROUTE
               || obj_stack->ip4_route.n_nexthops <= 1u || obj_stack->_ip4_route.extra_nexthops);
@@ -5287,11 +5319,14 @@ _ip_route_add(NMPlatform *self, NMPNlmFlags flags, NMPObject *obj_stack)
      *   is stack allocated (and the potential "extra_nexthops" array is
      *   guaranteed to stay alive too).
      */
-    return klass->ip_route_add(self, flags, obj_stack);
+    return klass->ip_route_add(self, flags, obj_stack, out_extack_msg);
 }
 
 int
-nm_platform_ip_route_add(NMPlatform *self, NMPNlmFlags flags, const NMPObject *obj)
+nm_platform_ip_route_add(NMPlatform      *self,
+                         NMPNlmFlags      flags,
+                         const NMPObject *obj,
+                         char           **out_extack_msg)
 {
     nm_auto_nmpobj const NMPObject *obj_keep_alive = NULL;
     NMPObject                       obj_stack;
@@ -5309,7 +5344,7 @@ nm_platform_ip_route_add(NMPlatform *self, NMPNlmFlags flags, const NMPObject *o
         obj_stack._ip4_route.extra_nexthops = obj->_ip4_route.extra_nexthops;
     }
 
-    return _ip_route_add(self, flags, &obj_stack);
+    return _ip_route_add(self, flags, &obj_stack, out_extack_msg);
 }
 
 int
@@ -5341,7 +5376,7 @@ nm_platform_ip4_route_add(NMPlatform                   *self,
                               &extra_nexthops_free);
     }
 
-    return _ip_route_add(self, flags, &obj);
+    return _ip_route_add(self, flags, &obj, NULL);
 }
 
 int
@@ -5350,7 +5385,7 @@ nm_platform_ip6_route_add(NMPlatform *self, NMPNlmFlags flags, const NMPlatformI
     NMPObject obj;
 
     nmp_object_stackinit(&obj, NMP_OBJECT_TYPE_IP6_ROUTE, (const NMPlatformObject *) route);
-    return _ip_route_add(self, flags, &obj);
+    return _ip_route_add(self, flags, &obj, NULL);
 }
 
 gboolean
diff --git a/src/libnm-platform/nm-platform.h b/src/libnm-platform/nm-platform.h
index 1cd9c6c6f9..39f8edabd8 100644
--- a/src/libnm-platform/nm-platform.h
+++ b/src/libnm-platform/nm-platform.h
@@ -1215,7 +1215,8 @@ typedef struct {
                                 guint32     lifetime,
                                 guint32     preferred_lft,
                                 guint32     flags,
-                                const char *label);
+                                const char *label,
+                                char      **out_extack_msg);
     gboolean (*ip6_address_add)(NMPlatform     *self,
                                 int             ifindex,
                                 struct in6_addr address,
@@ -1223,7 +1224,8 @@ typedef struct {
                                 struct in6_addr peer_address,
                                 guint32         lifetime,
                                 guint32         preferred_lft,
-                                guint32         flags);
+                                guint32         flags,
+                                char          **out_extack_msg);
     gboolean (*ip4_address_delete)(NMPlatform *self,
                                    int         ifindex,
                                    in_addr_t   address,
@@ -1234,7 +1236,11 @@ typedef struct {
                                    struct in6_addr address,
                                    guint8          plen);
 
-    int (*ip_route_add)(NMPlatform *self, NMPNlmFlags flags, NMPObject *obj_stack);
+    int (*ip_route_add)(NMPlatform *self,
+                        NMPNlmFlags flags,
+                        NMPObject  *obj_stack,
+                        char      **out_extack_msg);
+
     int (*ip_route_get)(NMPlatform   *self,
                         int           addr_family,
                         gconstpointer address,
@@ -2130,7 +2136,8 @@ gboolean nm_platform_ip4_address_add(NMPlatform *self,
                                      guint32     lifetime,
                                      guint32     preferred_lft,
                                      guint32     flags,
-                                     const char *label);
+                                     const char *label,
+                                     char      **out_extack_msg);
 gboolean nm_platform_ip6_address_add(NMPlatform     *self,
                                      int             ifindex,
                                      struct in6_addr address,
@@ -2138,7 +2145,8 @@ gboolean nm_platform_ip6_address_add(NMPlatform     *self,
                                      struct in6_addr peer_address,
                                      guint32         lifetime,
                                      guint32         preferred_lft,
-                                     guint32         flags);
+                                     guint32         flags,
+                                     char          **out_extack_msg);
 gboolean nm_platform_ip4_address_delete(NMPlatform *self,
                                         int         ifindex,
                                         in_addr_t   address,
@@ -2251,7 +2259,10 @@ nm_platform_ip_route_get_gateway(int addr_family, const NMPlatformIPRoute *route
     return &((NMPlatformIP6Route *) route)->gateway;
 }
 
-int nm_platform_ip_route_add(NMPlatform *self, NMPNlmFlags flags, const NMPObject *route);
+int nm_platform_ip_route_add(NMPlatform      *self,
+                             NMPNlmFlags      flags,
+                             const NMPObject *route,
+                             char           **out_extack_msg);
 int nm_platform_ip4_route_add(NMPlatform                   *self,
                               NMPNlmFlags                   flags,
                               const NMPlatformIP4Route     *route,
diff --git a/src/libnm-platform/nmp-global-tracker.c b/src/libnm-platform/nmp-global-tracker.c
index 3fd31e4e14..8f36c124ef 100644
--- a/src/libnm-platform/nmp-global-tracker.c
+++ b/src/libnm-platform/nmp-global-tracker.c
@@ -1101,7 +1101,7 @@ nmp_global_tracker_sync(NMPGlobalTracker *self, NMPObjectType obj_type, gboolean
                                          NMP_NLM_FLAG_ADD,
                                          NMP_OBJECT_CAST_ROUTING_RULE(obj_data->obj));
         } else
-            nm_platform_ip_route_add(self->platform, NMP_NLM_FLAG_APPEND, obj_data->obj);
+            nm_platform_ip_route_add(self->platform, NMP_NLM_FLAG_APPEND, obj_data->obj, NULL);
     }
 }