From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Mon, 4 Dec 2023 13:25:33 +0000 (+0100)
Subject: netfilter: nf_tables: bail out on mismatching dynset and set expressions
X-Git-Tag: v5.15.143~101
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=cf5f113c41eb2c7dbe19d849a0883f7a429fa54b;p=thirdparty%2Fkernel%2Fstable.git

netfilter: nf_tables: bail out on mismatching dynset and set expressions

[ Upstream commit 3701cd390fd731ee7ae8b8006246c8db82c72bea ]

If dynset expressions provided by userspace is larger than the declared
set expressions, then bail out.

Fixes: 48b0ae046ee9 ("netfilter: nftables: netlink support for several set element expressions")
Reported-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c
index 73e606372b05d..e714e0efa7363 100644
--- a/net/netfilter/nft_dynset.c
+++ b/net/netfilter/nft_dynset.c
@@ -279,10 +279,15 @@ static int nft_dynset_init(const struct nft_ctx *ctx,
 			priv->expr_array[i] = dynset_expr;
 			priv->num_exprs++;
 
-			if (set->num_exprs &&
-			    dynset_expr->ops != set->exprs[i]->ops) {
-				err = -EOPNOTSUPP;
-				goto err_expr_free;
+			if (set->num_exprs) {
+				if (i >= set->num_exprs) {
+					err = -EINVAL;
+					goto err_expr_free;
+				}
+				if (dynset_expr->ops != set->exprs[i]->ops) {
+					err = -EOPNOTSUPP;
+					goto err_expr_free;
+				}
 			}
 			i++;
 		}