From patchwork Sun Aug 5 00:35:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 953501 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=arista.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=arista.com header.i=@arista.com header.b="YCMAnW9l"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 41jhf86FqMz9s3x for ; Sun, 5 Aug 2018 10:36:00 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726754AbeHECia (ORCPT ); Sat, 4 Aug 2018 22:38:30 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:38161 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726069AbeHECia (ORCPT ); Sat, 4 Aug 2018 22:38:30 -0400 Received: by mail-ed1-f67.google.com with SMTP id t2-v6so3453988edr.5 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=iC96IDSlmEPvU0YXrKsy8vFOdbE0eV75f7MB3c7+EueIIrcdzUhNroGS9tvOPJalLa WuMmI5hXxdLHPhs9qMZ5tm9yClmgtBnWuiEaRtHxKspAG8LXB5gbfg6CV8HARxT7uh7l JxuEFu5jWwdPYP0VTYTX2/Am7FRrU29fbzSZsxjeX4bn072yJNLpIGbWrcQeT7gLPXmc gVa3Ai2dtu6Ya34KvVsuq6KIG2BnxYUswgam8MvpW6zNPom4zskr85ovwP9gJwjhzbiG Rh8RqRTIoPfSg11omtI/MEscwibSNLhPII59vtGpJmepeA7Y+aJxE/wOb87uqwhntiX0 +1aw== X-Gm-Message-State: AOUpUlFFKK2zepNETXUrel0Br7S/JAPGi9UpQKnChQ1vqh2V1jdpeCgh QU7nYA6rx/t/1sOyLjFcGPxvwg== 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: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@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) {