[bug report] wifi: mt76: mt7996: Rely on mt7996_sta_link in sta_add/sta_remove callbacks

[Dan Carpenter]

Hello Lorenzo Bianconi,

Commit dd82a9e02c05 ("wifi: mt76: mt7996: Rely on mt7996_sta_link in
sta_add/sta_remove callbacks") from Mar 11, 2025 (linux-next), leads
to the following Smatch static checker warning:

	drivers/net/wireless/mediatek/mt76/mt7996/main.c:1023 mt7996_mac_sta_add_links()
	error: uninitialized symbol 'err'.

drivers/net/wireless/mediatek/mt76/mt7996/main.c
    984 static int
    985 mt7996_mac_sta_add_links(struct mt7996_dev *dev, struct ieee80211_vif *vif,
    986                          struct ieee80211_sta *sta, unsigned long new_links)
    987 {
    988         struct mt7996_sta *msta = (struct mt7996_sta *)sta->drv_priv;
    989         unsigned int link_id;
    990         int err;
    991 
    992         for_each_set_bit(link_id, &new_links, IEEE80211_MLD_MAX_NUM_LINKS) {
    993                 struct ieee80211_bss_conf *link_conf;
    994                 struct ieee80211_link_sta *link_sta;
    995                 struct mt7996_vif_link *link;
    996 
    997                 if (rcu_access_pointer(msta->link[link_id]))
    998                         continue;

What about if there are no new links or we hit the continue on every
iteration.

    999 
    1000                 link_conf = link_conf_dereference_protected(vif, link_id);
    1001                 if (!link_conf)
    1002                         goto error_unlink;

error code?

    1003 
    1004                 link = mt7996_vif_link(dev, vif, link_id);
    1005                 if (!link)
    1006                         goto error_unlink;

error code?

    1007 
    1008                 link_sta = link_sta_dereference_protected(sta, link_id);
    1009                 if (!link_sta)
    1010                         goto error_unlink;

error code?

    1011 
    1012                 err = mt7996_mac_sta_init_link(dev, link_conf, link_sta, link,
    1013                                                link_id);
    1014                 if (err)
    1015                         goto error_unlink;
    1016         }
    1017 
    1018         return 0;
    1019 
    1020 error_unlink:
    1021         mt7996_mac_sta_remove_links(dev, sta, new_links);
    1022 
--> 1023         return err;
    1024 }

regards,
dan carpenter