From 1490609a3d82e494168a390b34094bacc5e83c02 Mon Sep 17 00:00:00 2001
From: Phil Sutter <psutter@redhat.com>
Date: Tue, 18 May 2021 18:06:50 +0200
Subject: [PATCH] monitor: Fix for use after free when printing map elements

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1919203
Upstream Status: nftables commit 02174ffad484d

commit 02174ffad484d9711678e5d415c32307efc39857
Author: Phil Sutter <phil@nwl.cc>
Date:   Thu Jan 9 17:43:11 2020 +0100

    monitor: Fix for use after free when printing map elements

    When populating the dummy set, 'data' field must be cloned just like
    'key' field.

    Fixes: 343a51702656a ("src: store expr, not dtype to track data in sets")
    Signed-off-by: Phil Sutter <phil@nwl.cc>
    Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 src/monitor.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/monitor.c b/src/monitor.c
index 7927b6f..142cc92 100644
--- a/src/monitor.c
+++ b/src/monitor.c
@@ -401,7 +401,8 @@ static int netlink_events_setelem_cb(const struct nlmsghdr *nlh, int type,
 	 */
 	dummyset = set_alloc(monh->loc);
 	dummyset->key = expr_clone(set->key);
-	dummyset->data = set->data;
+	if (set->data)
+		dummyset->data = expr_clone(set->data);
 	dummyset->flags = set->flags;
 	dummyset->init = set_expr_alloc(monh->loc, set);
 
-- 
2.31.1