nl80211: fix per-station group key get/del and memory leak

In case userspace attempts to obtain key information for or delete a
unicast key, this is currently erroneously rejected unless the driver
sets the WIPHY_FLAG_IBSS_RSN flag. Apparently enough drivers do so it
was never noticed.

Fix that, and while at it fix a potential memory leak: the error path
in the get_key() function was placed after allocating a message but
didn't free it - move it to a better place. Luckily admin permissions
are needed to call this operation.

Cc: stable@vger.kernel.org
Fixes: e31b82136d1ad ("cfg80211/mac80211: allow per-station GTKs")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 7ca4b5133123..8887c6e5fca8 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2854,6 +2854,9 @@ static int nl80211_get_key(struct sk_buff *skb, struct genl_info *info)
         if (!rdev->ops->get_key)
                 return -EOPNOTSUPP;
 
+        if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
+                return -ENOENT;
+
         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
         if (!msg)
                 return -ENOMEM;
@@ -2873,10 +2876,6 @@ static int nl80211_get_key(struct sk_buff *skb, struct genl_info *info)
             nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr))
                 goto nla_put_failure;
 
-        if (pairwise && mac_addr &&
-            !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
-                return -ENOENT;
-
         err = rdev_get_key(rdev, dev, key_idx, pairwise, mac_addr, &cookie,
                            get_key_callback);
 
@@ -3047,7 +3046,7 @@ static int nl80211_del_key(struct sk_buff *skb, struct genl_info *info)
         wdev_lock(dev->ieee80211_ptr);
         err = nl80211_key_allowed(dev->ieee80211_ptr);
 
-        if (key.type == NL80211_KEYTYPE_PAIRWISE && mac_addr &&
+        if (key.type == NL80211_KEYTYPE_GROUP && mac_addr &&
             !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
                 err = -ENOENT;