From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Wed, 25 Oct 2023 14:00:50 +0000 (+0200)
Subject: evaluate: reject set in concatenation
X-Git-Tag: v1.1.0~258
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4b6a4ad9134fa71277c2ff7f92776e1faeb83000;p=thirdparty%2Fnftables.git

evaluate: reject set in concatenation

Consider the following ruleset.

 define ext_if = { "eth0", "eth1" }
 table ip filter {
    chain c {
        iifname . tcp dport { $ext_if . 22 } accept
    }
 }

Attempting to load this ruleset results in:

BUG: invalid expression type 'set' in setnft: netlink.c:304: __netlink_gen_concat_key: Assertion `0' failed.
Aborted (core dumped)

After this patch:

 # nft -f ruleset.nft
 ruleset.nft:1:17-40: Error: cannot use set in concatenation
 define ext_if = { "eth0", "eth1" }
                 ^^^^^^^^^^^^^^^^^^

Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1715
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/src/evaluate.c b/src/evaluate.c
index 2196e928..894987df 100644
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -1511,6 +1511,12 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
 
 		if (list_member_evaluate(ctx, &i) < 0)
 			return -1;
+
+		if (i->etype == EXPR_SET)
+			return expr_error(ctx->msgs, i,
+					  "cannot use %s in concatenation",
+					  expr_name(i));
+
 		flags &= i->flags;
 
 		if (!key && i->dtype->type == TYPE_INTEGER) {