From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Sat, 2 Jul 2022 02:16:30 +0000 (+0200)
Subject: netfilter: nf_tables: stricter validation of element data
X-Git-Tag: archive/raspbian/5.10.127-2+rpi1^2~27
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks:///%22http:/www.example.com/cgi/%22https:/%22bookmarks:/?a=commitdiff_plain;h=f6d643f2a64f30520b80a1fbc89b4d5e9f619ae7;p=linux.git

netfilter: nf_tables: stricter validation of element data

Origin: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit?id=0a5e36dbcb448a7a8ba63d1d4b6ade2c9d3cc8bf
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2022-34918

commit 7e6bc1f6cabcd30aba0b11219d8e01b952eacbb6 upstream.

Make sure element data type and length do not mismatch the one specified
by the set declaration.

Fixes: 7d7402642eaf ("netfilter: nf_tables: variable sized set element keys / data")
Reported-by: Hugues ANGUELKOV <hanguelkov@randorisec.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Gbp-Pq: Topic bugfix/all
Gbp-Pq: Name netfilter-nf_tables-stricter-validation-of-element-d.patch
---

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 3c17fadaab5..e5622e925ea 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4886,13 +4886,20 @@ static int nft_setelem_parse_data(struct nft_ctx *ctx, struct nft_set *set,
 				  struct nft_data *data,
 				  struct nlattr *attr)
 {
+	u32 dtype;
 	int err;
 
 	err = nft_data_init(ctx, data, NFT_DATA_VALUE_MAXLEN, desc, attr);
 	if (err < 0)
 		return err;
 
-	if (desc->type != NFT_DATA_VERDICT && desc->len != set->dlen) {
+	if (set->dtype == NFT_DATA_VERDICT)
+		dtype = NFT_DATA_VERDICT;
+	else
+		dtype = NFT_DATA_VALUE;
+
+	if (dtype != desc->type ||
+	    set->dlen != desc->len) {
 		nft_data_release(data, desc->type);
 		return -EINVAL;
 	}