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FAILED: patch "[PATCH] netfilter: nf_tables: do not allow SET_ID to refer to another" failed to apply to 4.9-stable tree

PATCH [email protected] 1 participant 1 message Aug 13, 2022

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The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 470ee20e069a6d05ae549f7d0ef2bdbcee6a81b2 Mon Sep 17 00:00:00 2001
From: Thadeu Lima de Souza Cascardo <[email protected]>
Date: Tue, 9 Aug 2022 14:01:46 -0300
Subject: [PATCH] netfilter: nf_tables: do not allow SET_ID to refer to another
table

When doing lookups for sets on the same batch by using its ID, a set from a different table can be used.

Then, when the table is removed, a reference to the set may be kept after the set is freed, leading to a potential use-after-free.

When looking for sets by ID, use the table that was used for the lookup by name, and only return sets belonging to that same table.

This fixes CVE-2022-2586, also reported as ZDI-CAN-17470.

Fixes 958bee14d071 ("netfilter: nf_tables: use new transaction infrastructure to handle sets")
net/netfilter/nf_tables_api.c +3 -1
index 3b09e13b9b5c..41c529b0001c 100644
@@ -3842,6 +3842,7 @@ static struct nft_set *nft_set_lookup_byhandle(const struct nft_table *table,
 }
 
 static struct nft_set *nft_set_lookup_byid(const struct net *net,
+					   const struct nft_table *table,
 					   const struct nlattr *nla, u8 genmask)
 {
 	struct nftables_pernet *nft_net = nft_pernet(net);
@@ -3853,6 +3854,7 @@ static struct nft_set *nft_set_lookup_byid(const struct net *net,
 			struct nft_set *set = nft_trans_set(trans);
 
 			if (id == nft_trans_set_id(trans) &&
+			    set->table == table &&
 			    nft_active_genmask(set, genmask))
 				return set;
 		}
@@ -3873,7 +3875,7 @@ struct nft_set *nft_set_lookup_global(const struct net *net,
 		if (!nla_set_id)
 			return set;
 
-		set = nft_set_lookup_byid(net, nla_set_id, genmask);
+		set = nft_set_lookup_byid(net, table, nla_set_id, genmask);
 	}
 	return set;
 }