From nobody Wed Dec 17 23:56:57 2025 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 42E96770E7; Fri, 28 Jun 2024 05:41:13 +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=1719553274; cv=none; b=Dy83Y0XGlhNs7w+grPm8den5vEo0UOWRTFBKhI6wgIzSzpR/+X8P9hD/SkzJqkd89He2RUh3fNiQ1GKDecB2wSlIIUBqK1ym7fKHcUVPVDyc5e05tjdazPvNiyJw/rolJcnTxTBYbxwkkV/bYFEZXsGumoVlv9cdIJ7LGlPrpIg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719553274; c=relaxed/simple; bh=w3ls34DoAiYmcoRkVXaNAHsDTKPNzvjkfsGPhogxENo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=XwT/rONgXNbFIz2JNB3oLyntA17LGiAqsigaJHTl/udKnTYVkCNSixpMR2SWdGuEd15sPkuLVB60gpWO/5BZ6Sg6ztjLuBLtSoto3sPMZcrKHiU3yjK276xOF2uz8qZyGPpnzUYxkPt5Q94VzaLk5fb9M7EWtCGGWFUNNPOk22E= 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 3DEDA1400F3; Fri, 28 Jun 2024 14:41:12 +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 4.19 2/3] ipv6: Fix data races around sk->sk_prot. Date: Mon, 17 Apr 2023 16:54:27 +0000 Message-Id: <20230417165428.26284-3-kazunori.kobayashi@miraclelinux.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230417165428.26284-1-kazunori.kobayashi@miraclelinux.com> References: <20230417165428.26284-1-kazunori.kobayashi@miraclelinux.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" 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 c1d60df487fc0..fd467b96fceac 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -3064,7 +3064,8 @@ int sock_common_getsockopt(struct socket *sock, int l= evel, int optname, { struct sock *sk =3D sock->sk; =20 - 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, opt= len); } EXPORT_SYMBOL(sock_common_getsockopt); =20 @@ -3105,7 +3106,8 @@ int sock_common_setsockopt(struct socket *sock, int l= evel, int optname, { struct sock *sk =3D sock->sk; =20 - 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, opt= len); } EXPORT_SYMBOL(sock_common_setsockopt); =20 diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 3c9e05332f179..8ec107748159b 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 so= ckaddr *uaddr, int addr_len, int flags) { struct sock *sk =3D sock->sk; + const struct proto *prot; int err; =20 if (addr_len < sizeof(uaddr->sa_family)) return -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot =3D READ_ONCE(sk->sk_prot); + if (uaddr->sa_family =3D=3D AF_UNSPEC) - return sk->sk_prot->disconnect(sk, flags); + return prot->disconnect(sk, flags); =20 if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { - err =3D sk->sk_prot->pre_connect(sk, uaddr, addr_len); + err =3D prot->pre_connect(sk, uaddr, addr_len); if (err) return err; } =20 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); =20 @@ -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 =3D sock->sk; + struct sock *sk1 =3D sock->sk, *sk2; int err =3D -EINVAL; - struct sock *sk2 =3D sk1->sk_prot->accept(sk1, flags, &err, kern); =20 + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + sk2 =3D READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern); if (!sk2) goto do_err; =20 @@ -809,6 +815,7 @@ ssize_t inet_sendpage(struct socket *sock, struct page = *page, int offset, size_t size, int flags) { struct sock *sk =3D sock->sk; + const struct proto *prot; =20 sock_rps_record_flow(sk); =20 @@ -817,8 +824,10 @@ ssize_t inet_sendpage(struct socket *sock, struct page= *page, int offset, inet_autobind(sk)) return -EAGAIN; =20 - 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 =3D 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 91facff119357..625cece87c122 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -224,7 +224,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int leve= l, 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 =3D &ipv4_specific; sk->sk_socket->ops =3D &inet_stream_ops; @@ -239,7 +239,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int leve= l, 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 =3D &inet_dgram_ops; sk->sk_family =3D PF_INET; --=20 2.39.2