Subject: [PATCH iproute2 v2] ip/tunnel: always print all known attributes

From: Ilya Dmitrichenko <[email-masked]>
Date: Mon, 9 Aug 2021 11:23:00 +0100

Presently, if a Geneve or VXLAN interface was created with 'external',
it's not possible for a user to determine e.g. the value of 'dstport'
after creation. This change fixes that by avoiding early returns.

This change partly reverts commit 00ff4b8e31af ("ip/tunnel: Be consistent
when printing tunnel collect metadata").

Signed-off-by: Ilya Dmitrichenko <[email-masked]>
Acked-by: Daniel Borkmann <[email-masked]>
---
 ip/iplink_geneve.c | 12 ++++--------
 ip/iplink_vxlan.c  | 12 ++++--------
 ip/link_gre.c      |  1 -
 ip/link_gre6.c     |  1 -
 ip/link_ip6tnl.c   |  1 -
 ip/link_iptnl.c    |  1 -
 6 files changed, 8 insertions(+), 20 deletions(-)

diff --git a/ip/iplink_geneve.c b/ip/iplink_geneve.c
index 9299236c..78fc818e 100644
--- a/ip/iplink_geneve.c
+++ b/ip/iplink_geneve.c
@@ -243,7 +243,6 @@ static int geneve_parse_opt(struct link_util *lu, int argc, char **argv,
 
 static void geneve_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 {
-	__u32 vni;
 	__u8 ttl = 0;
 	__u8 tos = 0;
 
@@ -252,15 +251,12 @@ static void geneve_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 
 	if (tb[IFLA_GENEVE_COLLECT_METADATA]) {
 		print_bool(PRINT_ANY, "external", "external ", true);
-		return;
 	}
 
-	if (!tb[IFLA_GENEVE_ID] ||
-	    RTA_PAYLOAD(tb[IFLA_GENEVE_ID]) < sizeof(__u32))
-		return;
-
-	vni = rta_getattr_u32(tb[IFLA_GENEVE_ID]);
-	print_uint(PRINT_ANY, "id", "id %u ", vni);
+	if (tb[IFLA_GENEVE_ID] &&
+	    RTA_PAYLOAD(tb[IFLA_GENEVE_ID]) >= sizeof(__u32)) {
+		print_uint(PRINT_ANY, "id", "id %u ", rta_getattr_u32(tb[IFLA_GENEVE_ID]));
+	}
 
 	if (tb[IFLA_GENEVE_REMOTE]) {
 		__be32 addr = rta_getattr_u32(tb[IFLA_GENEVE_REMOTE]);
diff --git a/ip/iplink_vxlan.c b/ip/iplink_vxlan.c
index bae9d994..9afa3cca 100644
--- a/ip/iplink_vxlan.c
+++ b/ip/iplink_vxlan.c
@@ -408,7 +408,6 @@ static int vxlan_parse_opt(struct link_util *lu, int argc, char **argv,
 
 static void vxlan_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 {
-	__u32 vni;
 	__u8 ttl = 0;
 	__u8 tos = 0;
 	__u32 maxaddr;
@@ -419,15 +418,12 @@ static void vxlan_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 	if (tb[IFLA_VXLAN_COLLECT_METADATA] &&
 	    rta_getattr_u8(tb[IFLA_VXLAN_COLLECT_METADATA])) {
 		print_bool(PRINT_ANY, "external", "external ", true);
-		return;
 	}
 
-	if (!tb[IFLA_VXLAN_ID] ||
-	    RTA_PAYLOAD(tb[IFLA_VXLAN_ID]) < sizeof(__u32))
-		return;
-
-	vni = rta_getattr_u32(tb[IFLA_VXLAN_ID]);
-	print_uint(PRINT_ANY, "id", "id %u ", vni);
+	if (tb[IFLA_VXLAN_ID] &&
+	    RTA_PAYLOAD(tb[IFLA_VXLAN_ID]) >= sizeof(__u32)) {
+		print_uint(PRINT_ANY, "id", "id %u ", rta_getattr_u32(tb[IFLA_VXLAN_ID]));
+	}
 
 	if (tb[IFLA_VXLAN_GROUP]) {
 		__be32 addr = rta_getattr_u32(tb[IFLA_VXLAN_GROUP]);
diff --git a/ip/link_gre.c b/ip/link_gre.c
index 6d4a8be8..f462a227 100644
--- a/ip/link_gre.c
+++ b/ip/link_gre.c
@@ -442,7 +442,6 @@ static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 
 	if (tb[IFLA_GRE_COLLECT_METADATA]) {
 		print_bool(PRINT_ANY, "external", "external ", true);
-		return;
 	}
 
 	tnl_print_endpoint("remote", tb[IFLA_GRE_REMOTE], AF_INET);
diff --git a/ip/link_gre6.c b/ip/link_gre6.c
index f33598af..232d9bde 100644
--- a/ip/link_gre6.c
+++ b/ip/link_gre6.c
@@ -461,7 +461,6 @@ static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 
 	if (tb[IFLA_GRE_COLLECT_METADATA]) {
 		print_bool(PRINT_ANY, "external", "external ", true);
-		return;
 	}
 
 	if (tb[IFLA_GRE_FLAGS])
diff --git a/ip/link_ip6tnl.c b/ip/link_ip6tnl.c
index c7b49b02..2fcc13ef 100644
--- a/ip/link_ip6tnl.c
+++ b/ip/link_ip6tnl.c
@@ -344,7 +344,6 @@ static void ip6tunnel_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb
 
 	if (tb[IFLA_IPTUN_COLLECT_METADATA]) {
 		print_bool(PRINT_ANY, "external", "external ", true);
-		return;
 	}
 
 	if (tb[IFLA_IPTUN_FLAGS])
diff --git a/ip/link_iptnl.c b/ip/link_iptnl.c
index 636cdb2c..b25855ba 100644
--- a/ip/link_iptnl.c
+++ b/ip/link_iptnl.c
@@ -368,7 +368,6 @@ static void iptunnel_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[
 
 	if (tb[IFLA_IPTUN_COLLECT_METADATA]) {
 		print_bool(PRINT_ANY, "external", "external ", true);
-		return;
 	}
 
 	if (tb[IFLA_IPTUN_PROTO]) {
-- 
2.29.2