netdev - [PATCH net] ipv4: prevent potential spectre v1 gadget in ip_metrics

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230120133040.3623463-1-edumazet@google.com>
Date:   Fri, 20 Jan 2023 13:30:40 +0000
From:   Eric Dumazet <edumazet@...gle.com>
To:     "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>
Cc:     netdev@...r.kernel.org, eric.dumazet@...il.com,
        Eric Dumazet <edumazet@...gle.com>
Subject: [PATCH net] ipv4: prevent potential spectre v1 gadget in ip_metrics_convert()

	if (!type)
		continue;
	if (type > RTAX_MAX)
		return -EINVAL;
	...
	metrics[type - 1] = val;

@type being used as an array index, we need to prevent
cpu speculation or risk leaking kernel memory content.

Fixes: 6cf9dfd3bd62 ("net: fib: move metrics parsing to a helper")
Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 net/ipv4/metrics.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ipv4/metrics.c b/net/ipv4/metrics.c
index 7fcfdfd8f9def057cbe163b8b395cd2379d98152..0e3ee1532848c8f49e0a342b7c8ecc1c27684e67 100644
--- a/net/ipv4/metrics.c
+++ b/net/ipv4/metrics.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 #include <linux/netlink.h>
+#include <linux/nospec.h>
 #include <linux/rtnetlink.h>
 #include <linux/types.h>
 #include <net/ip.h>
@@ -25,6 +26,7 @@ static int ip_metrics_convert(struct net *net, struct nlattr *fc_mx,
 			return -EINVAL;
 		}
 
+		type = array_index_nospec(type, RTAX_MAX + 1);
 		if (type == RTAX_CC_ALGO) {
 			char tmp[TCP_CA_NAME_MAX];
 
-- 
2.39.1.405.gd4c25cc71f-goog