diff --git a/lib/libpfctl/libpfctl.c b/lib/libpfctl/libpfctl.c
--- a/lib/libpfctl/libpfctl.c
+++ b/lib/libpfctl/libpfctl.c
@@ -194,7 +194,7 @@
 	hdr = snl_create_genl_msg_request(&nw, family_id,
 	    start ? PFNL_CMD_START : PFNL_CMD_STOP);
 
-	snl_finalize_msg(&nw);
+	hdr = snl_finalize_msg(&nw);
 	seq_id = hdr->nlmsg_seq;
 
 	snl_send_message(&ss, hdr);
@@ -1161,7 +1161,7 @@
 	snl_init_writer(ss, &nw);
 	hdr = snl_create_genl_msg_request(&nw, family_id, PFNL_CMD_GETCREATORS);
 	hdr->nlmsg_flags |= NLM_F_DUMP;
-	snl_finalize_msg(&nw);
+	hdr = snl_finalize_msg(&nw);
 	uint32_t seq_id = hdr->nlmsg_seq;
 
 	snl_send_message(ss, hdr);
@@ -1309,7 +1309,7 @@
 	snl_init_writer(ss, &nw);
 	hdr = snl_create_genl_msg_request(&nw, family_id, PFNL_CMD_GETSTATES);
 	hdr->nlmsg_flags |= NLM_F_DUMP;
-	snl_finalize_msg(&nw);
+	hdr = snl_finalize_msg(&nw);
 	uint32_t seq_id = hdr->nlmsg_seq;
 
 	snl_send_message(ss, hdr);
diff --git a/sbin/ifconfig/af_inet.c b/sbin/ifconfig/af_inet.c
--- a/sbin/ifconfig/af_inet.c
+++ b/sbin/ifconfig/af_inet.c
@@ -355,7 +355,7 @@
 	ifahdr->ifa_family = AF_INET;
 	ifahdr->ifa_index = ifindex;
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (EINVAL);
 
 	nlmsg_seq = hdr->nlmsg_seq;
@@ -386,7 +386,7 @@
 	ifahdr->ifa_index = ifindex;
 	snl_add_msg_attr_ip4(&nw, IFA_LOCAL, &addr);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (EINVAL);
 	memset(&e, 0, sizeof(e));
 	snl_read_reply_code(ss, hdr->nlmsg_seq, &e);
@@ -426,7 +426,7 @@
 		snl_add_msg_attr_u32(&nw, IFAF_VHID, pdata->vhid);
 	snl_end_attr_nested(&nw, off);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ctx->io_ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ctx->io_ss, hdr))
 		return (0);
 
 	struct snl_errmsg_data e = {};
diff --git a/sbin/ifconfig/af_inet6.c b/sbin/ifconfig/af_inet6.c
--- a/sbin/ifconfig/af_inet6.c
+++ b/sbin/ifconfig/af_inet6.c
@@ -488,7 +488,7 @@
 		snl_add_msg_attr_u32(&nw, IFAF_VHID, pdata->vhid);
 	snl_end_attr_nested(&nw, off);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ctx->io_ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ctx->io_ss, hdr))
 		return (0);
 
 	struct snl_errmsg_data e = {};
diff --git a/sbin/ifconfig/ifconfig_netlink.c b/sbin/ifconfig/ifconfig_netlink.c
--- a/sbin/ifconfig/ifconfig_netlink.c
+++ b/sbin/ifconfig/ifconfig_netlink.c
@@ -171,7 +171,7 @@
 	hdr->nlmsg_flags |= NLM_F_DUMP;
 	snl_reserve_msg_object(&nw, struct ifinfomsg);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (NULL);
 
 	uint32_t nlmsg_seq = hdr->nlmsg_seq;
@@ -212,7 +212,7 @@
 	snl_reserve_msg_object(&nw, struct ifinfomsg);
 	snl_add_msg_attr_string(&nw, IFLA_IFNAME, ifname);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (0);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -247,7 +247,7 @@
 	hdr->nlmsg_flags |= NLM_F_DUMP;
 	snl_reserve_msg_object(&nw, struct ifaddrmsg);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return;
 
 	uint32_t nlmsg_seq = hdr->nlmsg_seq;
diff --git a/sbin/route/route_netlink.c b/sbin/route/route_netlink.c
--- a/sbin/route/route_netlink.c
+++ b/sbin/route/route_netlink.c
@@ -266,7 +266,7 @@
 	if (rt_metrics->rmx_weight > 0)
 		snl_add_msg_attr_u32(&nw, NL_RTA_WEIGHT, rt_metrics->rmx_weight);
 
-	if (snl_finalize_msg(&nw) && snl_send_message(ss, hdr)) {
+	if ((hdr = snl_finalize_msg(&nw)) && snl_send_message(ss, hdr)) {
 		struct snl_errmsg_data e = {};
 
 		hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -319,7 +319,7 @@
 	struct ifinfomsg *ifmsg = snl_reserve_msg_object(&nw, struct ifinfomsg);
 	if (ifmsg != NULL)
 		ifmsg->ifi_index = ifindex;
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return;
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -822,7 +822,7 @@
 	snl_add_msg_attr_u32(&nw, RTA_TABLE, r->rta_table);
 	snl_add_msg_attr_ip(&nw, RTA_DST, r->rta_dst);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (ENOMEM);
 
 	if (!snl_read_reply_code(ss, hdr->nlmsg_seq, &e)) {
@@ -869,7 +869,7 @@
 	rtm->rtm_family = af;
 	snl_add_msg_attr_u32(&nw, RTA_TABLE, fib);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss, hdr)) {
 		snl_free(&ss);
 		return (EINVAL);
 	}
diff --git a/sys/netlink/netlink_snl_generic.h b/sys/netlink/netlink_snl_generic.h
--- a/sys/netlink/netlink_snl_generic.h
+++ b/sys/netlink/netlink_snl_generic.h
@@ -106,7 +106,7 @@
 	snl_init_writer(ss, &nw);
 	hdr = snl_create_genl_msg_request(&nw, GENL_ID_CTRL, CTRL_CMD_GETFAMILY);
 	snl_add_msg_attr_string(&nw, CTRL_ATTR_FAMILY_NAME, family_name);
-	if (snl_finalize_msg(&nw) == NULL || !snl_send_message(ss, hdr))
+	if ((hdr = snl_finalize_msg(&nw)) == NULL || !snl_send_message(ss, hdr))
 		return (false);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
diff --git a/tests/sys/netlink/test_snl_generic.c b/tests/sys/netlink/test_snl_generic.c
--- a/tests/sys/netlink/test_snl_generic.c
+++ b/tests/sys/netlink/test_snl_generic.c
@@ -86,7 +86,7 @@
 	snl_init_writer(&ss, &nw);
 	hdr = snl_create_genl_msg_request(&nw, GENL_ID_CTRL, CTRL_CMD_GETFAMILY);
 	snl_add_msg_attr_string(&nw, CTRL_ATTR_FAMILY_NAME, "nlctrl");
-	snl_finalize_msg(&nw);
+	hdr = snl_finalize_msg(&nw);
 	snl_send_message(&ss, hdr);
 
 	hdr = snl_read_reply(&ss, hdr->nlmsg_seq);
diff --git a/usr.sbin/arp/arp_netlink.c b/usr.sbin/arp/arp_netlink.c
--- a/usr.sbin/arp/arp_netlink.c
+++ b/usr.sbin/arp/arp_netlink.c
@@ -63,7 +63,7 @@
 	struct ifinfomsg *ifmsg = snl_reserve_msg_object(&nw, struct ifinfomsg);
 	if (ifmsg != NULL)
 		ifmsg->ifi_index = ifindex;
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (false);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -116,7 +116,7 @@
 	snl_add_msg_attr_ip(&nw, RTA_DST, (struct sockaddr *)&dst);
 	snl_add_msg_attr_u32(&nw, RTA_TABLE, fibnum);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (0);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -148,7 +148,7 @@
 	snl_add_msg_attr_u32(&nw, NHAF_TABLE, fibnum);
 	snl_end_attr_nested(&nw, off);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (0);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -285,7 +285,7 @@
 		ndmsg->ndm_ifindex = ifindex;
 	}
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss_req, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss_req, hdr)) {
 		snl_free(&ss_req);
 		return (0);
 	}
@@ -355,7 +355,7 @@
 	}
 	snl_add_msg_attr_ip(&nw, NDA_DST, (struct sockaddr *)dst);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss, hdr)) {
 		snl_free(&ss);
 		return (1);
 	}
@@ -422,7 +422,7 @@
 		snl_end_attr_nested(&nw, off);
 	}
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss, hdr)) {
 		snl_free(&ss);
 		return (1);
 	}
diff --git a/usr.sbin/ndp/ndp_netlink.c b/usr.sbin/ndp/ndp_netlink.c
--- a/usr.sbin/ndp/ndp_netlink.c
+++ b/usr.sbin/ndp/ndp_netlink.c
@@ -76,7 +76,7 @@
 	struct ifinfomsg *ifmsg = snl_reserve_msg_object(&nw, struct ifinfomsg);
 	if (ifmsg != NULL)
 		ifmsg->ifi_index = ifindex;
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (false);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -152,7 +152,7 @@
 	snl_add_msg_attr_ip(&nw, RTA_DST, (struct sockaddr *)dst);
 	snl_add_msg_attr_u32(&nw, RTA_TABLE, fibnum);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (0);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -184,7 +184,7 @@
 	snl_add_msg_attr_u32(&nw, NHAF_TABLE, fibnum);
 	snl_end_attr_nested(&nw, off);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(ss, hdr))
 		return (0);
 
 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
@@ -327,7 +327,7 @@
 		ndmsg->ndm_ifindex = ifindex;
 	}
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss_req, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss_req, hdr)) {
 		snl_free(&ss_req);
 		return (0);
 	}
@@ -421,7 +421,7 @@
 	}
 	snl_add_msg_attr_ip(&nw, NDA_DST, (struct sockaddr *)&dst);
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss, hdr)) {
 		snl_free(&ss);
 		return (1);
 	}
@@ -493,7 +493,7 @@
 	snl_add_msg_attr_ip(&nw, NDA_DST, (struct sockaddr *)dst);
 	snl_add_msg_attr(&nw, NDA_LLADDR, sdl->sdl_alen, LLADDR(sdl));
 
-	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) {
+	if (! (hdr = snl_finalize_msg(&nw)) || !snl_send_message(&ss, hdr)) {
 		snl_free(&ss);
 		return (1);
 	}