From: Ben Greear In certain failure paths, the driver is not fully configured, and it fails to find the link object. We still need to remove pointers to the bss_conf to keep from crashing shortly afterwards. Search all indices for stale pointer if we cannot do the fast lookup by ID. Signed-off-by: Ben Greear --- drivers/net/wireless/intel/iwlwifi/mld/link.c | 42 +++++++++++++++---- 1 file changed, 34 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mld/link.c b/drivers/net/wireless/intel/iwlwifi/mld/link.c index b5430e8a73d6..1e4959ceb3db 100644 --- a/drivers/net/wireless/intel/iwlwifi/mld/link.c +++ b/drivers/net/wireless/intel/iwlwifi/mld/link.c @@ -504,23 +504,49 @@ void iwl_mld_remove_link(struct iwl_mld *mld, struct iwl_mld_vif *mld_vif = iwl_mld_vif_from_mac80211(bss_conf->vif); struct iwl_mld_link *link = iwl_mld_link_from_mac80211(bss_conf); bool is_deflink = link == &mld_vif->deflink; - u8 fw_id = link->fw_id; + u16 fw_id; - if (WARN_ON(!link || link->active)) - return; + if (WARN_ON_ONCE(!link)) { + IWL_ERR(mld, "Remove nonexistent link, bss_conf: 0x%px link-id: %d\n", + bss_conf, bss_conf->link_id); + fw_id = 0xffff; + } else { + fw_id = link->fw_id; + } + + /* Not cleaning it up seems worse than cleaning up an active link, + * so continue on even in warning case. + */ + if (link && WARN_ON_ONCE(link->active)) + IWL_ERR(mld, "Removing active link, id: %d\n", + bss_conf->link_id); iwl_mld_rm_link_from_fw(mld, bss_conf); /* Continue cleanup on failure */ - if (!is_deflink) + if (link && !is_deflink) kfree_rcu(link, rcu_head); + rcu_read_lock(); RCU_INIT_POINTER(mld_vif->link[bss_conf->link_id], NULL); - if (WARN_ON(fw_id >= mld->fw->ucode_capa.num_links)) - return; - - RCU_INIT_POINTER(mld->fw_id_to_bss_conf[fw_id], NULL); + if (fw_id >= mld->fw->ucode_capa.num_links) { + struct ieee80211_bss_conf *tmp_bss_conf; + int i; + + /* Search for any existing back-pointer */ + for (i = 0; i < ARRAY_SIZE(mld->fw_id_to_bss_conf); i++) { + tmp_bss_conf = rcu_dereference(mld->fw_id_to_bss_conf[i]); + if (tmp_bss_conf == bss_conf) { + IWL_ERR(mld, "WARNING: Found bss_conf in fw_id_to_bss_conf[%i], Nulling pointer.\n", + i); + RCU_INIT_POINTER(mld->fw_id_to_bss_conf[i], NULL); + } + } + } else { + RCU_INIT_POINTER(mld->fw_id_to_bss_conf[fw_id], NULL); + } + rcu_read_unlock(); } void iwl_mld_handle_missed_beacon_notif(struct iwl_mld *mld, -- 2.42.0