From: William Tu <u9012063@gmail.com>
Date: Thu, 17 May 2018 00:24:32 +0000 (-0700)
Subject: erspan: fix invalid erspan version.
X-Git-Tag: v5.15~8822^2~10
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=02f99df1875c11330cd0be69a40fa8ccd14749b2;p=platform%2Fkernel%2Flinux-starfive.git

erspan: fix invalid erspan version.

ERSPAN only support version 1 and 2.  When packets send to an
erspan device which does not have proper version number set,
drop the packet.  In real case, we observe multicast packets
sent to the erspan pernet device, erspan0, which does not have
erspan version configured.

Reported-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 9c169bb2444d..f200b304f76c 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -722,10 +722,12 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb,
 		erspan_build_header(skb, ntohl(tunnel->parms.o_key),
 				    tunnel->index,
 				    truncate, true);
-	else
+	else if (tunnel->erspan_ver == 2)
 		erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key),
 				       tunnel->dir, tunnel->hwid,
 				       truncate, true);
+	else
+		goto free_skb;
 
 	tunnel->parms.o_flags &= ~TUNNEL_KEY;
 	__gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_ERSPAN));
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 69727bc168cb..a3e1dec96a74 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -979,11 +979,14 @@ static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb,
 			erspan_build_header(skb, ntohl(t->parms.o_key),
 					    t->parms.index,
 					    truncate, false);
-		else
+		else if (t->parms.erspan_ver == 2)
 			erspan_build_header_v2(skb, ntohl(t->parms.o_key),
 					       t->parms.dir,
 					       t->parms.hwid,
 					       truncate, false);
+		else
+			goto tx_err;
+
 		fl6.daddr = t->parms.raddr;
 	}