nl80211: fix MAC address validation

MAC addresses have a fixed length. The current
policy allows passing < ETH_ALEN bytes, which
might result in reading beyond the buffer.

Cc: stable@vger.kernel.org
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index b3a476f..ffafda5 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -89,8 +89,8 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
        [NL80211_ATTR_IFINDEX] = { .type = NLA_U32 },
        [NL80211_ATTR_IFNAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ-1 },
 
-       [NL80211_ATTR_MAC] = { .type = NLA_BINARY, .len = ETH_ALEN },
-       [NL80211_ATTR_PREV_BSSID] = { .type = NLA_BINARY, .len = ETH_ALEN },
+       [NL80211_ATTR_MAC] = { .len = ETH_ALEN },
+       [NL80211_ATTR_PREV_BSSID] = { .len = ETH_ALEN },
 
        [NL80211_ATTR_KEY] = { .type = NLA_NESTED, },
        [NL80211_ATTR_KEY_DATA] = { .type = NLA_BINARY,