From: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Date: Tue, 15 Aug 2017 17:02:48 +0200
Subject: s390/qeth: reject multicast rxip addresses
Patch-mainline: v4.14-rc1
Git-commit: aa9bea0b081c015ad5d54a2cced0977917775ed7
References: bsc#1061024 FATE#323301

There exist different commands to add unicast and multicast addresses on
the OSA card. rxip addresses are always set as unicast addresses and
thus just unicast addresses should be allowed.

Adding a multicast address now fails and a grace message is generated.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/s390/net/qeth_l3_sys.c |   17 +++++++++++++++++
 1 file changed, 17 insertions(+)

--- a/drivers/s390/net/qeth_l3_sys.c
+++ b/drivers/s390/net/qeth_l3_sys.c
@@ -895,9 +895,26 @@ static ssize_t qeth_l3_dev_rxip_add4_sho
 static int qeth_l3_parse_rxipe(const char *buf, enum qeth_prot_versions proto,
 		 u8 *addr)
 {
+	__be32 ipv4_addr;
+	struct in6_addr ipv6_addr;
+
 	if (qeth_l3_string_to_ipaddr(buf, proto, addr)) {
 		return -EINVAL;
 	}
+	if (proto == QETH_PROT_IPV4) {
+		memcpy(&ipv4_addr, addr, sizeof(ipv4_addr));
+		if (ipv4_is_multicast(ipv4_addr)) {
+			QETH_DBF_MESSAGE(2, "multicast rxip not supported.\n");
+			return -EINVAL;
+		}
+	} else if (proto == QETH_PROT_IPV6) {
+		memcpy(&ipv6_addr, addr, sizeof(ipv6_addr));
+		if (ipv6_addr_is_multicast(&ipv6_addr)) {
+			QETH_DBF_MESSAGE(2, "multicast rxip not supported.\n");
+			return -EINVAL;
+		}
+	}
+
 	return 0;
 }