net: ipv6: addr: perform strict checks also for doit handlers

Make RTM_GETADDR's doit handler use strict checks when
NETLINK_F_STRICT_CHK is set.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 93d5ad2b1a69790384bd9cefa8e0b024e1714c97..339a82cfe5f2482c168438a1ce56c92929a5bd6a 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5179,6 +5179,52 @@ static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
        return inet6_dump_addr(skb, cb, type);
 }
 
+static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
+                                      const struct nlmsghdr *nlh,
+                                      struct nlattr **tb,
+                                      struct netlink_ext_ack *extack)
+{
+       struct ifaddrmsg *ifm;
+       int i, err;
+
+       if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+               NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
+               return -EINVAL;
+       }
+
+       ifm = nlmsg_data(nlh);
+       if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
+               NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
+               return -EINVAL;
+       }
+
+       if (!netlink_strict_get_check(skb))
+               return nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX,
+                                  ifa_ipv6_policy, extack);
+
+       err = nlmsg_parse_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
+                                ifa_ipv6_policy, extack);
+       if (err)
+               return err;
+
+       for (i = 0; i <= IFA_MAX; i++) {
+               if (!tb[i])
+                       continue;
+
+               switch (i) {
+               case IFA_TARGET_NETNSID:
+               case IFA_ADDRESS:
+               case IFA_LOCAL:
+                       break;
+               default:
+                       NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
+                       return -EINVAL;
+               }
+       }
+
+       return 0;
+}
+
 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
                             struct netlink_ext_ack *extack)
 {
@@ -5199,8 +5245,7 @@ static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
        struct sk_buff *skb;
        int err;
 
-       err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
-                         extack);
+       err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
        if (err < 0)
                return err;