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From 0b95e025ee195fd549a77916c14af38e9b25ac16 Mon Sep 17 00:00:00 2001
From: Ryan Sullivan <rysulliv@redhat.com>
Date: Tue, 16 Apr 2024 13:57:40 -0400
Subject: [KPATCH CVE-2024-1086] kpatch fixes for CVE-2024-1086

Kernels:
3.10.0-1160.102.1.el7
3.10.0-1160.105.1.el7
3.10.0-1160.108.1.el7


Kpatch-MR: https://gitlab.com/redhat/prdsc/rhel/src/kpatch/rhel-7/-/merge_requests/70
Approved-by: Joe Lawrence (@joe.lawrence)
Changes since last build:
[x86_64]:
nf_tables_api.o: changed function: nft_data_init

[ppc64le]:
nf_tables_api.o: changed function: nft_data_init
nf_tables_api.o: changed function: nft_del_setelem

---------------------------

Modifications: none

commit 03d2627c7d53c06b8b28f5a57eb48ddbc1829c12
Author: Florian Westphal <fwestpha@redhat.com>
Date:   Fri Feb 2 15:28:35 2024 +0100

    netfilter: nf_tables: reject QUEUE/DROP verdict parameters

    JIRA: https://issues.redhat.com/browse/RHEL-23500
    Upstream Status: commit f342de4e2f33
    CVE: CVE-2024-1086

    commit f342de4e2f33e0e39165d8639387aa6c19dff660
    Author: Florian Westphal <fw@strlen.de>
    Date:   Sat Jan 20 22:50:04 2024 +0100

        netfilter: nf_tables: reject QUEUE/DROP verdict parameters

        This reverts commit e0abdadcc6e1.

        core.c:nf_hook_slow assumes that the upper 16 bits of NF_DROP
        verdicts contain a valid errno, i.e. -EPERM, -EHOSTUNREACH or similar,
        or 0.

        Due to the reverted commit, its possible to provide a positive
        value, e.g. NF_ACCEPT (1), which results in use-after-free.

        Its not clear to me why this commit was made.

        NF_QUEUE is not used by nftables; "queue" rules in nftables
        will result in use of "nft_queue" expression.

        If we later need to allow specifiying errno values from userspace
        (do not know why), this has to call NF_DROP_GETERR and check that
        "err <= 0" holds true.

        Fixes: e0abdadcc6e1 ("netfilter: nf_tables: accept QUEUE/DROP verdict parameters")
        Cc: stable@vger.kernel.org
        Reported-by: Notselwyn <notselwyn@pwning.tech>
        Signed-off-by: Florian Westphal <fw@strlen.de>
        Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

    Signed-off-by: Florian Westphal <fwestpha@redhat.com>

Signed-off-by: Ryan Sullivan <rysulliv@redhat.com>
---
 net/netfilter/nf_tables_api.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index ed8a787ac400..940f947b5fe7 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4629,16 +4629,10 @@ static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
 	data->verdict.code = ntohl(nla_get_be32(tb[NFTA_VERDICT_CODE]));
 
 	switch (data->verdict.code) {
-	default:
-		switch (data->verdict.code & NF_VERDICT_MASK) {
-		case NF_ACCEPT:
-		case NF_DROP:
-		case NF_QUEUE:
-			break;
-		default:
-			return -EINVAL;
-		}
-		/* fall through */
+	case NF_ACCEPT:
+	case NF_DROP:
+	case NF_QUEUE:
+		break;
 	case NFT_CONTINUE:
 	case NFT_BREAK:
 	case NFT_RETURN:
@@ -4657,6 +4651,8 @@ static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
 		chain->use++;
 		data->verdict.chain = chain;
 		break;
+	default:
+		return -EINVAL;
 	}
 
 	desc->len = sizeof(data->verdict);
-- 
2.45.1