From patchwork Thu May 21 23:57:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Giuliano Procida X-Patchwork-Id: 225465 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIMWL_WL_MED, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D2DCC433E0 for ; Thu, 21 May 2020 23:57:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D90B2206D4 for ; Thu, 21 May 2020 23:57:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Ez+zqwBQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729211AbgEUX54 (ORCPT ); Thu, 21 May 2020 19:57:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728762AbgEUX54 (ORCPT ); Thu, 21 May 2020 19:57:56 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDA2DC061A0E for ; Thu, 21 May 2020 16:57:55 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id y7so7270044ybj.15 for ; Thu, 21 May 2020 16:57:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=SqxOE+9wT9bCDyiiANOmvuVw5V5WdLRN81dGOQgBRMU=; b=Ez+zqwBQSBo8ttL7BI+SVaEvfobE1o4Vvj2bxjAuiwVhIQV84fPGmEvXPHEHpdu2vz ld6W5rpGxdg+Gc7ZeIAzTwkIsI/9zBGxGTxi89lURBkTJbIPWKXLPs+0iA/OV3mC5D8D FFQZrGEMdAwJr9TS9XgA7wFMO1irsKlEM9W09Ql8LpGbpu8qIXE/AmHjG3I31L4aqGwU d2+Z79UAL3yvx0KexLKrxgTO2Yczso6Cl6ph2HPs7XurqH71wd8kk1Yey+izsh4iV93e XY2jlvx/nDzW810q7WJhwpa0i4Z2z/Y/TuzKDd1h+OlnFa5FqCyCalY4sfBFS2cDTE8v 4/rQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=SqxOE+9wT9bCDyiiANOmvuVw5V5WdLRN81dGOQgBRMU=; b=DxMmzGkpEH/7I1Nd0Np+tOYz9N7N8s9DCBEP5RTEWwxsX0Os47JweVdL9Yr+QYCw14 Pp6g7Jin5WIOps1HEmNwe1K6SW/teD4lDMlBcwGi+2+EMIjn2KZUi/uUJxXnpK0PFzB7 rOwYSbMPWIx1VP9ziZW0Vt7/5XMb9eeFE2jfDQobzhVbem7jVEGS96l9fx9bDjOH/AnN ZX6tbVwaSxPE4m7/ko+c1Ou8/PDfjS4bJQ7seZY6HPWn0Rgj/hdsDQJYQpLBO7Bzb6AB Z5YCv2fxPM5DFXMLIHY8cN6yel0MDikg/vZ1/10isZX6eVMAhJLsUAFpsIJFNk6eVA7L SrWg== X-Gm-Message-State: AOAM530kr6FqPyxgEtrCQOc9xvTkUtj+Iqqs6jmUSMQCj4Z/zxd/lxsD MVteCHcWK/pMMH2+GrUgJvfd4elRerjnRA== X-Google-Smtp-Source: ABdhPJxqi8+SghDFWbalyH03Km6jyC671K9FfvKIsIKxAksSTJz13uAFCH8eUN/TJptE8OLaSz0uuBOoVVfYng== X-Received: by 2002:a05:6902:6d1:: with SMTP id m17mr19964040ybt.372.1590105475123; Thu, 21 May 2020 16:57:55 -0700 (PDT) Date: Fri, 22 May 2020 00:57:14 +0100 In-Reply-To: <20200521235740.191338-1-gprocida@google.com> Message-Id: <20200521235740.191338-2-gprocida@google.com> Mime-Version: 1.0 References: <20200521235740.191338-1-gprocida@google.com> X-Mailer: git-send-email 2.27.0.rc0.183.gde8f92d652-goog Subject: [PATCH 01/27] l2tp: lock socket before checking flags in connect() From: Giuliano Procida To: greg@kroah.com Cc: stable@vger.kernel.org, Guillaume Nault , "David S . Miller" , Giuliano Procida Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Guillaume Nault commit 0382a25af3c771a8e4d5e417d1834cbe28c2aaac upstream. Socket flags aren't updated atomically, so the socket must be locked while reading the SOCK_ZAPPED flag. This issue exists for both l2tp_ip and l2tp_ip6. For IPv6, this patch also brings error handling for __ip6_datagram_connect() failures. Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Giuliano Procida --- include/net/ipv6.h | 2 ++ net/ipv6/datagram.c | 4 +++- net/l2tp/l2tp_ip.c | 19 ++++++++++++------- net/l2tp/l2tp_ip6.c | 16 +++++++++++----- 4 files changed, 28 insertions(+), 13 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 6258264a0bf7..94880f07bc06 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -915,6 +915,8 @@ int compat_ipv6_setsockopt(struct sock *sk, int level, int optname, int compat_ipv6_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen); +int __ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, + int addr_len); int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len); int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr, int addr_len); diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c index f33154365b64..389b6367a810 100644 --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -40,7 +40,8 @@ static bool ipv6_mapped_addr_any(const struct in6_addr *a) return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0); } -static int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) +int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, + int addr_len) { struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; struct inet_sock *inet = inet_sk(sk); @@ -213,6 +214,7 @@ out: fl6_sock_release(flowlabel); return err; } +EXPORT_SYMBOL_GPL(__ip6_datagram_connect); int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { diff --git a/net/l2tp/l2tp_ip.c b/net/l2tp/l2tp_ip.c index 58f87bdd12c7..fab122cc6aac 100644 --- a/net/l2tp/l2tp_ip.c +++ b/net/l2tp/l2tp_ip.c @@ -321,21 +321,24 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len struct sockaddr_l2tpip *lsa = (struct sockaddr_l2tpip *) uaddr; int rc; - if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */ - return -EINVAL; - if (addr_len < sizeof(*lsa)) return -EINVAL; if (ipv4_is_multicast(lsa->l2tp_addr.s_addr)) return -EINVAL; - rc = ip4_datagram_connect(sk, uaddr, addr_len); - if (rc < 0) - return rc; - lock_sock(sk); + /* Must bind first - autobinding does not work */ + if (sock_flag(sk, SOCK_ZAPPED)) { + rc = -EINVAL; + goto out_sk; + } + + rc = __ip4_datagram_connect(sk, uaddr, addr_len); + if (rc < 0) + goto out_sk; + l2tp_ip_sk(sk)->peer_conn_id = lsa->l2tp_conn_id; write_lock_bh(&l2tp_ip_lock); @@ -343,7 +346,9 @@ static int l2tp_ip_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len sk_add_bind_node(sk, &l2tp_ip_bind_table); write_unlock_bh(&l2tp_ip_lock); +out_sk: release_sock(sk); + return rc; } diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c index 2b5230ef8536..59e609f2db64 100644 --- a/net/l2tp/l2tp_ip6.c +++ b/net/l2tp/l2tp_ip6.c @@ -383,9 +383,6 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr, int addr_type; int rc; - if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */ - return -EINVAL; - if (addr_len < sizeof(*lsa)) return -EINVAL; @@ -402,10 +399,18 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr, return -EINVAL; } - rc = ip6_datagram_connect(sk, uaddr, addr_len); - lock_sock(sk); + /* Must bind first - autobinding does not work */ + if (sock_flag(sk, SOCK_ZAPPED)) { + rc = -EINVAL; + goto out_sk; + } + + rc = __ip6_datagram_connect(sk, uaddr, addr_len); + if (rc < 0) + goto out_sk; + l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id; write_lock_bh(&l2tp_ip6_lock); @@ -413,6 +418,7 @@ static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr, sk_add_bind_node(sk, &l2tp_ip6_bind_table); write_unlock_bh(&l2tp_ip6_lock); +out_sk: release_sock(sk); return rc;