@@ -2250,7 +2250,10 @@ static int ipaddr_modify(int cmd, int flags, int argc, char **argv)
} else if (strcmp(*argv, "home") == 0) {
ifa_flags |= IFA_F_HOMEADDRESS;
} else if (strcmp(*argv, "nodad") == 0) {
- ifa_flags |= IFA_F_NODAD;
+ if (req.ifa.ifa_family == AF_INET6)
+ ifa_flags |= IFA_F_NODAD;
+ else
+ invarg("nodad option can be set only for IPv6 addresses\n", *argv);
} else if (strcmp(*argv, "mngtmpaddr") == 0) {
ifa_flags |= IFA_F_MANAGETEMPADDR;
} else if (strcmp(*argv, "noprefixroute") == 0) {
Duplicate Address Detection (RFC 4862) is available only for IPv6 addresses. As a consequence, 'nodad' option, turning it off, should be available only for IPv6, and is defined like that in the man page. However it is possible to set nodad on IPv4 addresses, too: $ ip link add dummy0 type dummy $ ip -4 addr add 192.168.1.1 dev dummy0 nodad $ ip a 1: dummy0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 1a:6d:c6:96:ca:f8 brd ff:ff:ff:ff:ff:ff inet 192.168.1.1/32 scope global nodad dummy0 valid_lft forever preferred_lft forever Fix this adding a check on the protocol family before setting IFA_F_NODAD flag. Fixes: bac735c53a36d ("enabled to manipulate the flags of IFA_F_HOMEADDRESS or IFA_F_NODAD from ip.") Signed-off-by: Andrea Claudi <aclaudi@redhat.com> --- ip/ipaddress.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)