From: Breno Leitao <leitao@debian.org>
Date: Tue, 15 Apr 2025 19:28:52 +0000 (-0700)
Subject: ipv6: Use nlmsg_payload in addrlabel file
X-Git-Tag: v6.16-rc1~132^2~280^2~7
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5ef4097ed155b3eb3aa7ec2c6035c6800b0e849d;p=thirdparty%2Flinux.git

ipv6: Use nlmsg_payload in addrlabel file

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

This changes function ip6addrlbl_valid_get_req() and
ip6addrlbl_valid_dump_req().

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250415-nlmsg_v2-v1-1-a1c75d493fd7@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c
index ab054f329e12d..fb63ffbcfc647 100644
--- a/net/ipv6/addrlabel.c
+++ b/net/ipv6/addrlabel.c
@@ -473,12 +473,12 @@ static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
 {
 	struct ifaddrlblmsg *ifal;
 
-	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
+	ifal = nlmsg_payload(nlh, sizeof(*ifal));
+	if (!ifal) {
 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
 		return -EINVAL;
 	}
 
-	ifal = nlmsg_data(nlh);
 	if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
 	    ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
@@ -543,7 +543,8 @@ static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
 	struct ifaddrlblmsg *ifal;
 	int i, err;
 
-	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
+	ifal = nlmsg_payload(nlh, sizeof(*ifal));
+	if (!ifal) {
 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
 		return -EINVAL;
 	}
@@ -552,7 +553,6 @@ static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
 		return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
 					      IFAL_MAX, ifal_policy, extack);
 
-	ifal = nlmsg_data(nlh);
 	if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
 		return -EINVAL;