netfilter: nf_tables: do not compare internal table flags on updates

jira VULN-4985
cve CVE-2024-27065
commit-author Pablo Neira Ayuso <[email protected]>
commit 4a0e7f2

Restore skipping transaction if table update does not modify flags.

Fixes: 179d9ba ("netfilter: nf_tables: fix table flag updates")
	Signed-off-by: Pablo Neira Ayuso <[email protected]>
(cherry picked from commit 4a0e7f2)
	Signed-off-by: Greg Rose <[email protected]>

Author: gvrose8192

net/netfilter/nf_tables_api.c

@@ -967,7 +967,7 @@ static int nf_tables_updtable(struct nft_ctx *ctx)
 	if (flags & ~NFT_TABLE_F_DORMANT)
 		return -EINVAL;
 
-	if (flags == ctx->table->flags)
+	if (flags == (ctx->table->flags & NFT_TABLE_F_MASK))
 		return 0;
 
 	/* No dormant off/on/off/on games in single transaction */