mac80211: Fix key freeing to handle unlinked keys
Key locking simplification removed key->sdata != NULL verification from
ieee80211_key_free(). While that is fine for most use cases, there is one
path where this function can be called with an unlinked key (i.e.,
key->sdata == NULL && key->local == NULL). This results in a NULL pointer
dereference with the current implementation. This is known to happen at
least with FT protocol when wpa_supplicant tries to configure the key
before association.
Avoid the issue by passing in the local pointer to
ieee80211_key_free(). In addition, do not clear the key from hw_accel
or debugfs if it has not yet been added. At least the hw_accel one could
trigger another NULL pointer dereference.
Signed-off-by: Jouni Malinen <j@w1.fi>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index b769567..dab6b8e 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -158,7 +158,7 @@
if (mac_addr) {
sta = sta_info_get_bss(sdata, mac_addr);
if (!sta) {
- ieee80211_key_free(key);
+ ieee80211_key_free(sdata->local, key);
err = -ENOENT;
goto out_unlock;
}
@@ -192,7 +192,7 @@
goto out_unlock;
if (sta->key) {
- ieee80211_key_free(sta->key);
+ ieee80211_key_free(sdata->local, sta->key);
WARN_ON(sta->key);
ret = 0;
}
@@ -205,7 +205,7 @@
goto out_unlock;
}
- ieee80211_key_free(sdata->keys[key_idx]);
+ ieee80211_key_free(sdata->local, sdata->keys[key_idx]);
WARN_ON(sdata->keys[key_idx]);
ret = 0;