wifi: mac80211: check link exists before use

If the assoc link doesn't exist yet at this point, we
cannot use it yet. This isn't normally the case, but
e.g. in case of FT-DS (or just broken userspace) the
link might not be set up yet and will only be created
later in this function. Check that the link exists.

Fixes: 310c8387c638 ("wifi: mac80211: clean up connection process")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/3151f5d0-c18f-413d-b34b-b94f095b947c@moroto.mountain
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240301193633.c886d300e90a.Ie1d5e23b2a033d934d343c37249f6f4dfddcc5fe@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 89c4165f2753000e53406ecf9f93ba3edb0347b8..c60d23da91fe3e08e35eaf808830d1dbb8e89186 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -8173,7 +8173,7 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata,
                                eth_random_addr(assoc_data->link[i].addr);
                        sband = local->hw.wiphy->bands[link_cbss->channel->band];
 
-                       if (match_auth && i == assoc_link_id)
+                       if (match_auth && i == assoc_link_id && link)
                                assoc_data->link[i].conn = link->u.mgd.conn;
                        else
                                assoc_data->link[i].conn =