From: Phil Sutter <phil@nwl.cc>
Date: Fri, 16 May 2025 18:08:05 +0000 (+0200)
Subject: netlink: Avoid potential NULL-ptr deref parsing set elem expressions
X-Git-Tag: v1.1.4~83
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=89645d04106d45d5e23b6d5206777dad1fb3e6bf;p=thirdparty%2Fnftables.git

netlink: Avoid potential NULL-ptr deref parsing set elem expressions

Since netlink_parse_set_expr() may return NULL, the following deref must
be guarded.

Fixes: e6d1d0d611958 ("src: add set element multi-statement support")
Signed-off-by: Phil Sutter <phil@nwl.cc>
---

diff --git a/src/netlink.c b/src/netlink.c
index d8891245..0724190a 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -969,7 +969,8 @@ static int set_elem_parse_expressions(struct nftnl_expr *e, void *data)
 	struct stmt *stmt;
 
 	stmt = netlink_parse_set_expr(set, cache, e);
-	list_add_tail(&stmt->list, &setelem_parse_ctx->stmt_list);
+	if (stmt)
+		list_add_tail(&stmt->list, &setelem_parse_ctx->stmt_list);
 
 	return 0;
 }