cfg80211: validate key index better

Don't accept it if a key_idx < 0 snuck through, reject WEP keys with
key index 4 and 5 (which are used for IGTKs) and don't allow IGTKs
with key indices other than 4 and 5. This makes the key data match
expectations better.

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

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 0675f51..12e2d3f 100644 (file)
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -218,7 +218,7 @@ int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
                                   struct key_params *params, int key_idx,
                                   bool pairwise, const u8 *mac_addr)
 {
-       if (key_idx > 5)
+       if (key_idx < 0 || key_idx > 5)
                return -EINVAL;
 
        if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
@@ -249,7 +249,13 @@ int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
                /* Disallow BIP (group-only) cipher as pairwise cipher */
                if (pairwise)
                        return -EINVAL;
+               if (key_idx < 4)
+                       return -EINVAL;
                break;
+       case WLAN_CIPHER_SUITE_WEP40:
+       case WLAN_CIPHER_SUITE_WEP104:
+               if (key_idx > 3)
+                       return -EINVAL;
        default:
                break;
        }