l2tp: remove l2specific_len configurable parameter

Remove l2specific_len configuration parameter since now L2-Specific
Sublayer length is computed according to l2specific_type provided by
userspace.
Reviewed-by: Guillaume Nault <g.nault@alphalink.fr>
Tested-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/l2tp/l2tp_core.c

@@ -1777,7 +1777,6 @@ struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunn
 			session->lns_mode = cfg->lns_mode;
 			session->reorder_timeout = cfg->reorder_timeout;
 			session->l2specific_type = cfg->l2specific_type;
-			session->l2specific_len = cfg->l2specific_len;
 			session->cookie_len = cfg->cookie_len;
 			memcpy(&session->cookie[0], &cfg->cookie[0], cfg->cookie_len);
 			session->peer_cookie_len = cfg->peer_cookie_len;

net/l2tp/l2tp_core.h

@@ -59,7 +59,6 @@ struct l2tp_session_cfg {
 	int			debug;		/* bitmask of debug message
 						 * categories */
 	u16			vlan_id;	/* VLAN pseudowire only */
-	u16			l2specific_len;	/* Layer 2 specific length */
 	u16			l2specific_type; /* Layer 2 specific type */
 	u8			cookie[8];	/* optional cookie */
 	int			cookie_len;	/* 0, 4 or 8 bytes */
@@ -85,7 +84,6 @@ struct l2tp_session {
 	int			cookie_len;
 	u8			peer_cookie[8];
 	int			peer_cookie_len;
-	u16			l2specific_len;
 	u16			l2specific_type;
 	u16			hdr_len;
 	u32			nr;		/* session NR state (receive) */

net/l2tp/l2tp_debugfs.c

@@ -181,7 +181,7 @@ static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
 		   session->debug,
 		   jiffies_to_msecs(session->reorder_timeout));
 	seq_printf(m, "   offset 0 l2specific %hu/%hu\n",
-		   session->l2specific_type, session->l2specific_len);
+		   session->l2specific_type, l2tp_get_l2specific_len(session));
 	if (session->cookie_len) {
 		seq_printf(m, "   cookie %02x%02x%02x%02x",
 			   session->cookie[0], session->cookie[1],

net/l2tp/l2tp_netlink.c

@@ -561,10 +561,6 @@ static int l2tp_nl_cmd_session_create(struct sk_buff *skb, struct genl_info *inf
 			cfg.l2specific_type = L2TP_L2SPECTYPE_DEFAULT;
 		}
 
-		cfg.l2specific_len = 4;
-		if (info->attrs[L2TP_ATTR_L2SPEC_LEN])
-			cfg.l2specific_len = nla_get_u8(info->attrs[L2TP_ATTR_L2SPEC_LEN]);
-
 		if (info->attrs[L2TP_ATTR_COOKIE]) {
 			u16 len = nla_len(info->attrs[L2TP_ATTR_COOKIE]);
 			if (len > 8) {