[PATCH v2 net] ipv4: Add ICMPv6 support when parse route ipproto

[Hangbin Liu]

For ip rules, we need to use 'ipproto ipv6-icmp' to match ICMPv6 headers.
But for ip -6 route, currently we only support tcp, udp and icmp.

Add ICMPv6 support so we can match ipv6-icmp rules for route lookup.

v2: As David Ahern and Sabrina Dubroca suggested, Add an argument to
rtm_getroute_parse_ip_proto() to handle ICMP/ICMPv6 with different family.

Reported-by: Jianlin Shi <ji...@redhat.com>
Fixes: eacb9384a3fe ("ipv6: support sport, dport and ip_proto in RTM_GETROUTE")
Signed-off-by: Hangbin Liu <liuhang...@gmail.com>
---
 include/net/ip.h   |  2 +-
 net/ipv4/netlink.c | 17 +++++++++++++----
 net/ipv4/route.c   |  2 +-
 net/ipv6/route.c   |  3 ++-
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/include/net/ip.h b/include/net/ip.h
index 8866bfce6121..80300e8a6280 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -716,7 +716,7 @@ extern int sysctl_icmp_msgs_burst;
 int ip_misc_proc_init(void);
 #endif
 
-int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto,
+int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
                                struct netlink_ext_ack *extack);
 
 #endif /* _IP_H */
diff --git a/net/ipv4/netlink.c b/net/ipv4/netlink.c
index f86bb4f06609..d8e3a1fb8e82 100644
--- a/net/ipv4/netlink.c
+++ b/net/ipv4/netlink.c
@@ -3,9 +3,10 @@
 #include <linux/types.h>
 #include <net/net_namespace.h>
 #include <net/netlink.h>
+#include <linux/in6.h>
 #include <net/ip.h>
 
-int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto,
+int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family,
                                struct netlink_ext_ack *extack)
 {
        *ip_proto = nla_get_u8(attr);
@@ -13,11 +14,19 @@ int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 
*ip_proto,
        switch (*ip_proto) {
        case IPPROTO_TCP:
        case IPPROTO_UDP:
+               return 0;
        case IPPROTO_ICMP:
+               if (family != AF_INET)
+                       break;
+               return 0;
+#if IS_ENABLED(CONFIG_IPV6)
+       case IPPROTO_ICMPV6:
+               if (family != AF_INET6)
+                       break;
                return 0;
-       default:
-               NL_SET_ERR_MSG(extack, "Unsupported ip proto");
-               return -EOPNOTSUPP;
+#endif
        }
+       NL_SET_ERR_MSG(extack, "Unsupported ip proto");
+       return -EOPNOTSUPP;
 }
 EXPORT_SYMBOL_GPL(rtm_getroute_parse_ip_proto);
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 5163b64f8fb3..7bb9128c8363 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2803,7 +2803,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, 
struct nlmsghdr *nlh,
 
        if (tb[RTA_IP_PROTO]) {
                err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
-                                                 &ip_proto, extack);
+                                                 &ip_proto, AF_INET, extack);
                if (err)
                        return err;
        }
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ce15dc4ccbfa..6f949aa5b64f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -4889,7 +4889,8 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, 
struct nlmsghdr *nlh,
 
        if (tb[RTA_IP_PROTO]) {
                err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
-                                                 &fl6.flowi6_proto, extack);
+                                                 &fl6.flowi6_proto, AF_INET6,
+                                                 extack);
                if (err)
                        goto errout;
        }
-- 
2.19.2