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>

1 files changed, 7 insertions, 1 deletions

diff --git a/net/wireless/util.c b/net/wireless/util.c
index 0675f513e7b9..12e2d3fae843 100644
--- 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;
         }