From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT 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 9C773C4646D for ; Sun, 5 Aug 2018 00:36:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 479BB217C1 for ; Sun, 5 Aug 2018 00:36:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="YCMAnW9l" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 479BB217C1 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=arista.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727296AbeHECic (ORCPT ); Sat, 4 Aug 2018 22:38:32 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:45904 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726275AbeHECia (ORCPT ); Sat, 4 Aug 2018 22:38:30 -0400 Received: by mail-ed1-f68.google.com with SMTP id s16-v6so3443448edq.12 for ; Sat, 04 Aug 2018 17:35:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=googlenew; h=from:to:cc:subject:date:message-id; bh=8jr4ubE/89EJDjqVIiMcByHCHqgz22N9cboNFoT1jj0=; b=YCMAnW9lrJqDVtC/d3gc/kZVqdFZd8URQFxPfNmsjF6iHo9wdkw0OjsZ9CiLw0C9rQ ekQbo0qE4G1mZFfpoCDhvSe6FS/iXX9U78q1Nsb3Zuu7iAGabCWi4Ue+97iA7h+CaQhD VIs1CQvvF4PUG36W+iGyv0PFmkM+54T4WALqhKk+1KPGNfTWz0ASo5dJ3wG29mGD8qoO sRxI4FoGZTaDQSbcbXZgdUtPhGGUByNBeDKqO6k55+1Iom6nyWshrwP7FONKq2nAYxJ8 PKJIw5/f93gqcy0hEuHKedFDeUKzq7pWbF9oFKagHhON6qwv9CkTEVHV1YVoJ3wcv8xr xS8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=8jr4ubE/89EJDjqVIiMcByHCHqgz22N9cboNFoT1jj0=; b=MhRHJ5ITXA5qXGhmmosu8nIEdTdmnGhV/tlJCCw2KT2lSSb9/alW6qO5tydzwG+vvC 9ndENG6C69ctzbH60PWEXKiI5vIcPKGsGqfTt7JBlVLplBDyQKXLCp+8/hNJFW2GL4+7 OJ5vvxfuFExSI5HpMKN/6fsFJf5XzSazGiDSVhjxDdLDBwCHiG/Nr9zC79hBAwfhDoA7 Gv7aY37BwQofR4j3v/ZHqkDr0I9JLH7IjZmVOS9vFESyGQzLScqaMzqkfuBL7yd+lDUQ 3L1ZWLcOXhnzdeMziBe+99MUKSY3m1Qjdlea8Wpu9+7XayA1fPJUYW/izTZKbihXkxAX UvAw== X-Gm-Message-State: AOUpUlFvbb3XgU8SjRibHyExA8IoWXPOTl1PlXZQpc5gZQZhqxb4a2zx UDIAnSS3kMpzEcZrtOlHFxgNeY6956I= X-Google-Smtp-Source: AAOMgpdqxyAqRiyZikXH67zd2XPsiuaTL5puOeKkSAqpww25aqpCsfEeouymyMQ5MXK+oV/+WShPPw== X-Received: by 2002:a50:89d3:: with SMTP id h19-v6mr12498657edh.140.1533429356628; Sat, 04 Aug 2018 17:35:56 -0700 (PDT) Received: from localhost.localdomain ([2a02:8084:ea2:c100:5459:5b7e:632c:59fc]) by smtp.gmail.com with ESMTPSA id q26-v6sm4164249eda.35.2018.08.04.17.35.54 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sat, 04 Aug 2018 17:35:55 -0700 (PDT) From: Dmitry Safonov To: linux-kernel@vger.kernel.org Cc: Dmitry Safonov , Nathan Chancellor , "David S. Miller" , Herbert Xu , Steffen Klassert , netdev@vger.kernel.org, stable@vger.kernel.org Subject: [PATCHv2] netlink: Don't shift on 64 for ngroups Date: Sun, 5 Aug 2018 01:35:53 +0100 Message-Id: <20180805003553.11104-1-dima@arista.com> X-Mailer: git-send-email 2.13.6 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It's legal to have 64 groups for netlink_sock. As user-supplied nladdr->nl_groups is __u32, it's possible to subscribe only to first 32 groups. The check for correctness of .bind() userspace supplied parameter is done by applying mask made from ngroups shift. Which broke Android as they have 64 groups and the shift for mask resulted in an overflow. Fixes: 61f4b23769f0 ("netlink: Don't shift with UB on nlk->ngroups") Cc: "David S. Miller" Cc: Herbert Xu Cc: Steffen Klassert Cc: netdev@vger.kernel.org Cc: stable@vger.kernel.org Reported-and-Tested-by: Nathan Chancellor Signed-off-by: Dmitry Safonov --- v2: sizeof() is in bytes net/netlink/af_netlink.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 7d860a22e5fb..d6ff4d409437 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1011,8 +1011,8 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr, if (nlk->ngroups == 0) groups = 0; - else - groups &= (1ULL << nlk->ngroups) - 1; + else if (nlk->ngroups < 8*sizeof(groups)) + groups &= (1UL << nlk->ngroups) - 1; bound = nlk->bound; if (bound) { -- 2.13.6