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