From: Breno Leitao <leitao@debian.org>
Date: Tue, 15 Apr 2025 19:28:55 +0000 (-0700)
Subject: ipv4: Use nlmsg_payload in devinet file
X-Git-Tag: v6.16-rc1~132^2~280^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7d82cc229c0901b0fa677f2568b436bcf8dcada7;p=thirdparty%2Flinux.git

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 77e5705ac799e..c47d3828d4f65 100644
--- 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;