cfg80211: Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE

Buffer overread may happen as nl80211_set_station() reads 4 bytes
from the attribute NL80211_ATTR_LOCAL_MESH_POWER_MODE without
validating the size of data received when userspace sends less
than 4 bytes of data with NL80211_ATTR_LOCAL_MESH_POWER_MODE.
Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE to avoid
the buffer overread.

Fixes: 3b1c5a53 ("{cfg,nl}80211: mesh power mode primitives and userspace access")
Cc: stable@vger.kernel.org
Signed-off-by: Srinivas Dasari <dasaris@qti.qualcomm.com>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/nl80211.c

@@ -347,6 +347,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_SCAN_FLAGS] = { .type = NLA_U32 },
 	[NL80211_ATTR_P2P_CTWINDOW] = { .type = NLA_U8 },
 	[NL80211_ATTR_P2P_OPPPS] = { .type = NLA_U8 },
+	[NL80211_ATTR_LOCAL_MESH_POWER_MODE] = {. type = NLA_U32 },
 	[NL80211_ATTR_ACL_POLICY] = {. type = NLA_U32 },
 	[NL80211_ATTR_MAC_ADDRS] = { .type = NLA_NESTED },
 	[NL80211_ATTR_STA_CAPABILITY] = { .type = NLA_U16 },