ipv6: Use nlmsg_payload in inet6_rtm_valid_getaddr_req

Leverage the new nlmsg_payload() helper to avoid checking for message
size and then reading the nlmsg data.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250414-nlmsg-v2-7-3d90cb42c6af@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index a9aeb949d9c8e1efb05d1da89d3d5e2075809b2f..4af276179542833c266e6c1db0b3663bfe773454 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5484,7 +5484,8 @@ static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
        struct ifaddrmsg *ifm;
        int i, err;
 
-       if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+       ifm = nlmsg_payload(nlh, sizeof(*ifm));
+       if (!ifm) {
                NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
                return -EINVAL;
        }
@@ -5493,7 +5494,6 @@ static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
                return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
                                              ifa_ipv6_policy, extack);
 
-       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;