From: Paolo Abeni <pabeni@redhat.com>
Date: Tue, 15 Dec 2015 11:18:04 +0000 (+0100)
Subject: lwtunnel: fix argument parsing
X-Git-Tag: v4.4.0~15
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f0df40810f1c0bc86cf1fcb6f660b0fd9912b1d3;p=thirdparty%2Fiproute2.git

lwtunnel: fix argument parsing

Currently parse_encap_ip() does not update correctly argv/argc;
if multiple lwtunnel arguments are provided, the parsing fails after
the first one, i.e.

 ip route add 172.16.101.0/24 dev vxlan1 encap ip id 42 dst 192.168.255.1

fails with:

 Error: either "to" is duplicate, or "dst" is a garbage.

This commit addresses the issue, stepping to next argument at each iteration
of the parsing loop.

Fixes: 1e5293056a02 ("lwtunnel: Add encapsulation support to ip route")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---

diff --git a/ip/iproute_lwtunnel.c b/ip/iproute_lwtunnel.c
index b2764a6ca..1243977cc 100644
--- a/ip/iproute_lwtunnel.c
+++ b/ip/iproute_lwtunnel.c
@@ -201,10 +201,14 @@ static int parse_encap_ip(struct rtattr *rta, size_t len, int *argcp, char ***ar
 		} else {
 			break;
 		}
+		argc--; argv++;
 	}
 
-	*argcp = argc;
-	*argvp = argv;
+	/* argv is currently the first unparsed argument,
+	 * but the lwt_parse_encap() caller will move to the next,
+	 * so step back */
+	*argcp = argc + 1;
+	*argvp = argv - 1;
 
 	return 0;
 }