ipv4: Use nlmsg_payload in devinet file

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/20250415-nlmsg_v2-v1-4-a1c75d493fd7@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 77e5705ac799eb89fc5330a44d3d6f89e9df3092..c47d3828d4f6563346619c9b1ac7aec437bd086d 100644 (file)
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -1792,12 +1792,12 @@ static int inet_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
        struct ifaddrmsg *ifm;
        int err, i;
 
-       if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+       ifm = nlmsg_payload(nlh, sizeof(*ifm));
+       if (!ifm) {
                NL_SET_ERR_MSG(extack, "ipv4: Invalid header for address dump request");
                return -EINVAL;
        }
 
-       ifm = nlmsg_data(nlh);
        if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
                NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for address dump request");
                return -EINVAL;