From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.priv.miraclelinux.com (202x210x215x66.ap202.ftth.ucom.ne.jp [202.210.215.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 14EC3446BF; Fri, 28 Jun 2024 05:40:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.210.215.66 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719553241; cv=none; b=IGsYvtew90EOCIN/tQXDgzxA2odWrFPcUpEYIB2oEwwg5Cu7OQnzJxLiaQYjPty3fb+Wv2mFIx60rbA9qhqLAE8Tu0uvrF/ybc4eB2KEHkua/AqYtvDKjdqCrcTR0N9u8gv28Pqo4aGE/AxsFtuEKKAXWAHF01BzM4J6DQRsb9I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719553241; c=relaxed/simple; bh=4oL2u/lCzEFZbIK1/nFG/z9ifzk8aFo6ZOhSVILqbIU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=RthrUk2E5owkEn4NbxlFLaqJCJLtXcog0w6OTd4x4VtyG7jEkHi/AVb1FGwwm3u3XAChh/UmvxSzjrZOpVacmSAi4fuuLzKBeBA1N+0qYxDg2QsotX1ysrblfkB54llMRls4l7i2Z0+Omzex0inH6nOHvbuKT//2QEGBiyuy+Ik= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=miraclelinux.com; spf=pass smtp.mailfrom=miraclelinux.com; arc=none smtp.client-ip=202.210.215.66 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=miraclelinux.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=miraclelinux.com Received: from cip-lava-a.miraclelinux.com (cip-lava-a.miraclelinux.com [10.2.1.116]) by smtp.priv.miraclelinux.com (Postfix) with ESMTP id BB04C140103; Fri, 28 Jun 2024 14:40:38 +0900 (JST) From: Kazunori Kobayashi To: netdev@vger.kernel.org Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org, hiraku.toyooka@miraclelinux.com, Kuniyuki Iwashima , Jakub Kicinski , Kazunori Kobayashi Subject: [PATCH 5.4 2/3] ipv6: Fix data races around sk->sk_prot. Date: Mon, 17 Apr 2023 16:54:05 +0000 Message-Id: <20230417165406.26237-3-kazunori.kobayashi@miraclelinux.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230417165406.26237-1-kazunori.kobayashi@miraclelinux.com> References: <20230417165406.26237-1-kazunori.kobayashi@miraclelinux.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: From: Kuniyuki Iwashima commit 364f997b5cfe1db0d63a390fe7c801fa2b3115f6 upstream. Commit 086d49058cd8 ("ipv6: annotate some data-races around sk->sk_prot") fixed some data-races around sk->sk_prot but it was not enough. Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid load tearing. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski Signed-off-by: Kazunori Kobayashi --- net/core/sock.c | 6 ++++-- net/ipv4/af_inet.c | 23 ++++++++++++++++------- net/ipv6/ipv6_sockglue.c | 4 ++-- 3 files changed, 22 insertions(+), 11 deletions(-) diff --git a/net/core/sock.c b/net/core/sock.c index 2b68a93adfa8d..a8359770fd93a 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -3172,7 +3172,8 @@ int sock_common_getsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk; - return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_getsockopt); @@ -3213,7 +3214,8 @@ int sock_common_setsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk; - return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_setsockopt); diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index d7ebee3c048d5..d0293d051637b 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -553,22 +553,27 @@ int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; int err; if (addr_len < sizeof(uaddr->sa_family)) return -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (uaddr->sa_family == AF_UNSPEC) - return sk->sk_prot->disconnect(sk, flags); + return prot->disconnect(sk, flags); if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { - err = sk->sk_prot->pre_connect(sk, uaddr, addr_len); + err = prot->pre_connect(sk, uaddr, addr_len); if (err) return err; } if (!inet_sk(sk)->inet_num && inet_autobind(sk)) return -EAGAIN; - return sk->sk_prot->connect(sk, uaddr, addr_len); + return prot->connect(sk, uaddr, addr_len); } EXPORT_SYMBOL(inet_dgram_connect); @@ -731,10 +736,11 @@ EXPORT_SYMBOL(inet_stream_connect); int inet_accept(struct socket *sock, struct socket *newsock, int flags, bool kern) { - struct sock *sk1 = sock->sk; + struct sock *sk1 = sock->sk, *sk2; int err = -EINVAL; - struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern); if (!sk2) goto do_err; @@ -815,12 +821,15 @@ ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; if (unlikely(inet_send_prepare(sk))) return -EAGAIN; - if (sk->sk_prot->sendpage) - return sk->sk_prot->sendpage(sk, page, offset, size, flags); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (prot->sendpage) + return prot->sendpage(sk, page, offset, size, flags); return sock_no_sendpage(sock, page, offset, size, flags); } EXPORT_SYMBOL(inet_sendpage); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 1c329a951c4d3..4e4a34a40001b 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -222,7 +222,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, &tcp_prot, 1); local_bh_enable(); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */ WRITE_ONCE(sk->sk_prot, &tcp_prot); icsk->icsk_af_ops = &ipv4_specific; sk->sk_socket->ops = &inet_stream_ops; @@ -237,7 +237,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, prot, 1); local_bh_enable(); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */ WRITE_ONCE(sk->sk_prot, prot); sk->sk_socket->ops = &inet_dgram_ops; sk->sk_family = PF_INET; -- 2.39.2