nl80211: Add more through validation of MLME command parameters

Check that the used authentication type and reason code are valid here
so that drivers/mac80211 do not need to care about this. In addition,
remove the unnecessary validation of SSID attribute length which is
taken care of by netlink policy.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 26 insertions, 6 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 44c79972be57..6f38ee7a3c92 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2614,6 +2614,14 @@ static int nl80211_dump_scan(struct sk_buff *skb,
         return err;
 }
 
+static bool nl80211_valid_auth_type(enum nl80211_auth_type auth_type)
+{
+        return auth_type == NL80211_AUTHTYPE_OPEN_SYSTEM ||
+                auth_type == NL80211_AUTHTYPE_SHARED_KEY ||
+                auth_type == NL80211_AUTHTYPE_FT ||
+                auth_type == NL80211_AUTHTYPE_NETWORK_EAP;
+}
+
 static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
 {
         struct cfg80211_registered_device *drv;
@@ -2666,6 +2674,10 @@ static int nl80211_authenticate(struct sk_buff *skb, struct genl_info *info)
         if (info->attrs[NL80211_ATTR_AUTH_TYPE]) {
                 req.auth_type =
                         nla_get_u32(info->attrs[NL80211_ATTR_AUTH_TYPE]);
+                if (!nl80211_valid_auth_type(req.auth_type)) {
+                        err = -EINVAL;
+                        goto out;
+                }
         }
 
         err = drv->ops->auth(&drv->wiphy, dev, &req);
@@ -2718,10 +2730,6 @@ static int nl80211_associate(struct sk_buff *skb, struct genl_info *info)
                 }
         }
 
-        if (nla_len(info->attrs[NL80211_ATTR_SSID]) > IEEE80211_MAX_SSID_LEN) {
-                err = -EINVAL;
-                goto out;
-        }
         req.ssid = nla_data(info->attrs[NL80211_ATTR_SSID]);
         req.ssid_len = nla_len(info->attrs[NL80211_ATTR_SSID]);
 
@@ -2769,9 +2777,15 @@ static int nl80211_deauthenticate(struct sk_buff *skb, struct genl_info *info)
 
         req.peer_addr = nla_data(info->attrs[NL80211_ATTR_MAC]);
 
-        if (info->attrs[NL80211_ATTR_REASON_CODE])
+        if (info->attrs[NL80211_ATTR_REASON_CODE]) {
                 req.reason_code =
                         nla_get_u16(info->attrs[NL80211_ATTR_REASON_CODE]);
+                if (req.reason_code == 0) {
+                        /* Reason Code 0 is reserved */
+                        err = -EINVAL;
+                        goto out;
+                }
+        }
 
         if (info->attrs[NL80211_ATTR_IE]) {
                 req.ie = nla_data(info->attrs[NL80211_ATTR_IE]);
@@ -2817,9 +2831,15 @@ static int nl80211_disassociate(struct sk_buff *skb, struct genl_info *info)
 
         req.peer_addr = nla_data(info->attrs[NL80211_ATTR_MAC]);
 
-        if (info->attrs[NL80211_ATTR_REASON_CODE])
+        if (info->attrs[NL80211_ATTR_REASON_CODE]) {
                 req.reason_code =
                         nla_get_u16(info->attrs[NL80211_ATTR_REASON_CODE]);
+                if (req.reason_code == 0) {
+                        /* Reason Code 0 is reserved */
+                        err = -EINVAL;
+                        goto out;
+                }
+        }
 
         if (info->attrs[NL80211_ATTR_IE]) {
                 req.ie = nla_data(info->attrs[NL80211_ATTR_IE]);