linux-kernel - [PATCH 5.18 041/158] tcp: Fix data-races around sysctl_tcp_l3mdev

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

Date:   Wed, 27 Jul 2022 18:11:45 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Kuniyuki Iwashima <kuniyu@...zon.com>,
        "David S. Miller" <davem@...emloft.net>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.18 041/158] tcp: Fix data-races around sysctl_tcp_l3mdev_accept.

From: Kuniyuki Iwashima <kuniyu@...zon.com>

[ Upstream commit 08a75f10679470552a3a443f9aefd1399604d31d ]

While reading sysctl_tcp_l3mdev_accept, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 6dd9a14e92e5 ("net: Allow accepted sockets to be bound to l3mdev domain")
Signed-off-by: Kuniyuki Iwashima <kuniyu@...zon.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 include/net/inet_hashtables.h | 2 +-
 include/net/inet_sock.h       | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index 98e1ec1a14f0..749bb1e46087 100644
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -207,7 +207,7 @@ static inline bool inet_sk_bound_dev_eq(struct net *net, int bound_dev_if,
 					int dif, int sdif)
 {
 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
-	return inet_bound_dev_eq(!!net->ipv4.sysctl_tcp_l3mdev_accept,
+	return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept),
 				 bound_dev_if, dif, sdif);
 #else
 	return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index b29108f0973a..6395f6b9a5d2 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -121,7 +121,7 @@ static inline int inet_request_bound_dev_if(const struct sock *sk,
 #ifdef CONFIG_NET_L3_MASTER_DEV
 	struct net *net = sock_net(sk);
 
-	if (!bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept)
+	if (!bound_dev_if && READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept))
 		return l3mdev_master_ifindex_by_index(net, skb->skb_iif);
 #endif
 
@@ -133,7 +133,7 @@ static inline int inet_sk_bound_l3mdev(const struct sock *sk)
 #ifdef CONFIG_NET_L3_MASTER_DEV
 	struct net *net = sock_net(sk);
 
-	if (!net->ipv4.sysctl_tcp_l3mdev_accept)
+	if (!READ_ONCE(net->ipv4.sysctl_tcp_l3mdev_accept))
 		return l3mdev_master_ifindex_by_index(net,
 						      sk->sk_bound_dev_if);
 #endif
-- 
2.35.1