From ed565f91469987e1b6eaf0e0263fe2b02853ed7b Mon Sep 17 00:00:00 2001 From: Beniamino Galvani Date: Sat, 9 Sep 2023 13:53:25 +0200 Subject: [PATCH] l3cfg: fix pruning of ACD data If a commit is invoked without any change to the l3cd or to the ACD data, in _l3cfg_update_combined_config() we skip calling _l3_acd_data_add_all(), which should clear the dirty flag from ACDs. Therefore, in case of such no-op commits the ACDs still marked as dirty - but valid - are removed via: _l3_commit() _l3_acd_data_process_changes() _l3_acd_data_prune() _l3_acd_data_prune_one() Invoking a l3cfg commit without any actual changes is allowed, see the explanation in commit e773559d9d92 ('device: schedule an idle commit when setting device's sys-iface-state'). The bug is visible by running test 'bond_addreses_restart_persistence' with IPv4 ACD/DAD is enabled by default: after restart IPv6 completes immediately, the devices becomes ACTIVATED, the sys-iface-state transitions from ASSUME to MANAGED, a commit is done, and it incorrectly prunes the ACD data. The result is that the IPv4 address is never added again. Fix this by doing the pruning only when we update the dirty flags. --- src/core/nm-l3cfg.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/src/core/nm-l3cfg.c b/src/core/nm-l3cfg.c index 2d0c372b72..42f18a6982 100644 --- a/src/core/nm-l3cfg.c +++ b/src/core/nm-l3cfg.c @@ -334,6 +334,7 @@ typedef struct _NML3CfgPrivate { bool nacd_acd_not_supported : 1; bool acd_ipv4_addresses_on_link_has : 1; + bool acd_data_pruning_needed : 1; bool changed_configs_configs : 1; bool changed_configs_acd_state : 1; @@ -3059,7 +3060,10 @@ _l3_acd_data_process_changes(NML3Cfg *self) AcdData *acd_data; gint64 now_msec = 0; - _l3_acd_data_prune(self, FALSE); + if (self->priv.p->acd_data_pruning_needed) + _l3_acd_data_prune(self, FALSE); + + self->priv.p->acd_data_pruning_needed = FALSE; c_list_for_each_entry (acd_data, &self->priv.p->acd_lst_head, acd_lst) { _l3_acd_data_state_change(self, @@ -3789,6 +3793,8 @@ _l3cfg_update_combined_config(NML3Cfg *self, NM_SET_OUT(out_changed_combined_l3cd, FALSE); + self->priv.p->acd_data_pruning_needed = FALSE; + if (!self->priv.p->changed_configs_configs) { if (!self->priv.p->changed_configs_acd_state) goto out; @@ -3836,6 +3842,7 @@ _l3cfg_update_combined_config(NML3Cfg *self, self->priv.p->changed_configs_acd_state = TRUE; } else { _l3_acd_data_add_all(self, l3_config_datas_arr, l3_config_datas_len, reapply); + self->priv.p->acd_data_pruning_needed = TRUE; self->priv.p->changed_configs_acd_state = FALSE; }