mac80211: verify ieee80211_key_replace() arguments

There's no code calling ieee80211_key_replace() with both
arguments NULL and it wouldn't make sense, but in the
interest of maintainability add a warning for it. As a
side effect, this also shuts up a smatch warning.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 3e51dd7d98b3..ab8468047200 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -260,6 +260,10 @@ static void ieee80211_key_replace(struct ieee80211_sub_if_data *sdata,
         int idx;
         bool defunikey, defmultikey, defmgmtkey;
 
+        /* caller must provide at least one old/new */
+        if (WARN_ON(!new && !old))
+                return;
+
         if (new)
                 list_add_tail(&new->list, &sdata->key_list);