6.16-stable review patch. If anyone has any objections, please let me know.
------------------
From: Miri Korenblit miriam.rachel.korenblit@intel.com
[ Upstream commit be1ba9ed221ffb95a8bb15f4c83d0694225ba808 ]
If we get to the error path of ieee80211_prep_connection, for example because of a FW issue, then ieee80211_vif_set_links is called with 0. But the call to drv_change_vif_links from ieee80211_vif_update_links will probably fail as well, for the same reason. In this case, the valid_links and active_links bitmaps will be reverted to the value of the failing connection. Then, in the next connection, due to the logic of ieee80211_set_vif_links_bitmaps, valid_links will be set to the ID of the new connection assoc link, but the active_links will remain with the ID of the old connection's assoc link. If those IDs are different, we get into a weird state of valid_links and active_links being different. One of the consequences of this state is to call drv_change_vif_links with new_links as 0, since the & operation between the bitmaps will be 0.
Since a removal of a link should always succeed, ignore the return value of drv_change_vif_links if it was called to only remove links, which is the case for the ieee80211_prep_connection's error path. That way, the bitmaps will not be reverted to have the value from the failing connection and will have 0, so the next connection will have a good state.
Signed-off-by: Miri Korenblit miriam.rachel.korenblit@intel.com Reviewed-by: Johannes Berg johannes.berg@intel.com Link: https://patch.msgid.link/20250609213231.ba2011fb435f.Id87ff6dab5e1cf757b5409... Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/mac80211.h | 2 ++ net/mac80211/link.c | 9 ++++++++- 2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 1b79e948b925..2e9d1c0bf5ac 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -4468,6 +4468,8 @@ struct ieee80211_prep_tx_info { * new links bitmaps may be 0 if going from/to a non-MLO situation. * The @old array contains pointers to the old bss_conf structures * that were already removed, in case they're needed. + * Note that removal of link should always succeed, so the return value + * will be ignored in a removal only case. * This callback can sleep. * @change_sta_links: Change the valid links of a station, similar to * @change_vif_links. This callback can sleep. diff --git a/net/mac80211/link.c b/net/mac80211/link.c index 4f7b7d0f64f2..d71eabe5abf8 100644 --- a/net/mac80211/link.c +++ b/net/mac80211/link.c @@ -2,7 +2,7 @@ /* * MLO link handling * - * Copyright (C) 2022-2024 Intel Corporation + * Copyright (C) 2022-2025 Intel Corporation */ #include <linux/slab.h> #include <linux/kernel.h> @@ -368,6 +368,13 @@ static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata, ieee80211_update_apvlan_links(sdata); }
+ /* + * Ignore errors if we are only removing links as removal should + * always succeed + */ + if (!new_links) + ret = 0; + if (ret) { /* restore config */ memcpy(sdata->link, old_data, sizeof(old_data));