l3cfg: fix assertion failure in _l3_hook_add_obj_cb()

With nm_l3cfg_get_combined_l3cd(), we can get the commited or
the combined (next) l3cd. The commits is easy, it's cached already.

However, the combined needs to be computed first, if there were any
changes. For that we call _l3cfg_update_combined_config(), which then
also calls nm_l3_config_data_merge().

But in non-commit mode, _l3cfg_update_combined_config() doesn't call
_l3_acd_data_add_all(), so in _l3_hook_add_obj_cb() the ACD data may
not be as expected. This can previously hit an assertion.

1 files changed, 29 insertions, 19 deletions

diff --git a/src/core/nm-l3cfg.c b/src/core/nm-l3cfg.c
index 99611a1fc0..3ef4a31125 100644
--- a/src/core/nm-l3cfg.c
+++ b/src/core/nm-l3cfg.c
@@ -1337,12 +1337,6 @@ nm_l3cfg_get_acd_is_pending(NML3Cfg *self)
     return self->priv.p->acd_is_pending;
 }
 
-static gboolean
-_acd_track_data_is_not_dirty(const NML3AcdAddrTrackInfo *acd_track)
-{
-    return acd_track && !acd_track->_priv.acd_dirty_track;
-}
-
 static void
 _acd_track_data_clear(NML3AcdAddrTrackInfo *acd_track)
 {
@@ -3348,6 +3342,7 @@ typedef struct {
     NML3Cfg *     self;
     gconstpointer tag;
     bool          assume_config_once;
+    bool          to_commit;
 } L3ConfigMergeHookAddObjData;
 
 static gboolean
@@ -3379,24 +3374,38 @@ _l3_hook_add_obj_cb(const NML3ConfigData *     l3cd,
 
         acd_data = _l3_acd_data_find(self, addr);
 
-        if (!acd_data) {
-            /* we don't yet track an ACD state for this address. That can only
-             * happened during _l3cfg_update_combined_config() with !to_commit,
-             * where we didn't update the ACD state.
-             *
-             * This means, unless you actually commit, nm_l3cfg_get_combined_l3cd(self, get_commited = FALSE)
-             * won't consider IPv4 addresses ready, that have no known ACD state yet. */
+        if (!hook_data->to_commit) {
             nm_assert(self->priv.p->changed_configs_acd_state);
-            acd_bad = TRUE;
-            goto out_ip4_address;
+            /* We don't do an actual commit in _l3cfg_update_combined_config(). That means our acd-data
+             * is not up to date. Check whether we have no acd_data ready, and if not, consider the address
+             * as not ready. It cannot be ready until the next commit starts ACD. */
+            if (!acd_data) {
+                acd_bad = TRUE;
+                goto out_ip4_address;
+            }
+            nm_assert(({
+                NML3AcdAddrTrackInfo *_ti =
+                    _acd_data_find_track(acd_data, l3cd, obj, hook_data->tag);
+
+                !_ti || _ti->_priv.acd_dirty_track;
+            }));
+        } else {
+            /* If we commit, we called _l3_acd_data_add_all(), thus our acd_data must be present
+             * and not dirty. */
+            nm_assert(({
+                NML3AcdAddrTrackInfo *_ti =
+                    _acd_data_find_track(acd_data, l3cd, obj, hook_data->tag);
+
+                _ti && !_ti->_priv.acd_dirty_track;
+            }));
         }
 
-        nm_assert(_acd_track_data_is_not_dirty(
-            _acd_data_find_track(acd_data, l3cd, obj, hook_data->tag)));
         if (!NM_IN_SET(acd_data->info.state,
                        NM_L3_ACD_ADDR_STATE_READY,
-                       NM_L3_ACD_ADDR_STATE_DEFENDING))
+                       NM_L3_ACD_ADDR_STATE_DEFENDING)) {
             acd_bad = TRUE;
+            goto out_ip4_address;
+        }
 
 out_ip4_address:
         hook_result->ip4acd_not_ready = acd_bad ? NM_OPTION_BOOL_TRUE : NM_OPTION_BOOL_FALSE;
@@ -3472,7 +3481,8 @@ _l3cfg_update_combined_config(NML3Cfg *              self,
 
     if (l3_config_datas_len > 0) {
         L3ConfigMergeHookAddObjData hook_data = {
-            .self = self,
+            .self      = self,
+            .to_commit = to_commit,
         };
 
         l3cd = nm_l3_config_data_new(nm_platform_get_multi_idx(self->priv.platform),