From 9ee6278b78859e8a9e303ec4a037b4e76d6ed89a Mon Sep 17 00:00:00 2001
From: "Alexander V. Chernikov" <melifaro@FreeBSD.org>
Date: Sat, 18 Mar 2023 14:01:46 +0000
Subject: [PATCH] netstat: fix double-free in netlink error code path.

CID:	1504382
---
 usr.bin/netstat/route_netlink.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/usr.bin/netstat/route_netlink.c b/usr.bin/netstat/route_netlink.c
index 3546603ca1cc..6e7e505c9619 100644
--- a/usr.bin/netstat/route_netlink.c
+++ b/usr.bin/netstat/route_netlink.c
@@ -91,10 +91,8 @@ prepare_ifmap_netlink(struct snl_state *ss, size_t *pifmap_size)
 	};
 	msg.hdr.nlmsg_len = sizeof(msg);
 
-	if (!snl_send_message(ss, &msg.hdr)) {
-		snl_free(ss);
+	if (!snl_send_message(ss, &msg.hdr))
 		return (NULL);
-	}
 
 	struct ifmap_entry *ifmap = NULL;
 	uint32_t ifmap_size = 0;
@@ -286,6 +284,10 @@ p_rtable_netlink(int fibnum, int af)
 		return (false);
 
 	ifmap = prepare_ifmap_netlink(&ss, &ifmap_size);
+	if (ifmap == NULL) {
+		snl_free(&ss);
+		return (false);
+	}
 
 	struct {
 		struct nlmsghdr hdr;