mac80211: Don't squash error codes in key setup functions

ieee80211_add_key() currently returns -ENOMEM in case of any error,
including a missing crypto algorithm.  Change ieee80211_key_alloc()
and ieee80211_aes_{key_setup_encrypt,cmac_key_setup}() to encode
errors with ERR_PTR() rather than returning NULL, and change
ieee80211_add_key() accordingly.

Compile-tested only.

Reported-by: Marcin Owsiany <porridge@debian.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 1b9d87ed143a..d6dbc8ea4ead 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -234,13 +234,13 @@ struct ieee80211_key *ieee80211_key_alloc(enum ieee80211_key_alg alg,
                                           size_t seq_len, const u8 *seq)
 {
         struct ieee80211_key *key;
-        int i, j;
+        int i, j, err;
 
         BUG_ON(idx < 0 || idx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS);
 
         key = kzalloc(sizeof(struct ieee80211_key) + key_len, GFP_KERNEL);
         if (!key)
-                return NULL;
+                return ERR_PTR(-ENOMEM);
 
         /*
          * Default to software encryption; we'll later upload the
@@ -296,9 +296,10 @@ struct ieee80211_key *ieee80211_key_alloc(enum ieee80211_key_alg alg,
                  * it does not need to be initialized for every packet.
                  */
                 key->u.ccmp.tfm = ieee80211_aes_key_setup_encrypt(key_data);
-                if (!key->u.ccmp.tfm) {
+                if (IS_ERR(key->u.ccmp.tfm)) {
+                        err = PTR_ERR(key->u.ccmp.tfm);
                         kfree(key);
-                        return NULL;
+                        key = ERR_PTR(err);
                 }
         }
 
@@ -309,9 +310,10 @@ struct ieee80211_key *ieee80211_key_alloc(enum ieee80211_key_alg alg,
                  */
                 key->u.aes_cmac.tfm =
                         ieee80211_aes_cmac_key_setup(key_data);
-                if (!key->u.aes_cmac.tfm) {
+                if (IS_ERR(key->u.aes_cmac.tfm)) {
+                        err = PTR_ERR(key->u.aes_cmac.tfm);
                         kfree(key);
-                        return NULL;
+                        key = ERR_PTR(err);
                 }
         }