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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 DF356C4646D for ; Sun, 5 Aug 2018 00:53:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 929D8217CC for ; Sun, 5 Aug 2018 00:53:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 929D8217CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net 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 S1727350AbeHEC4U (ORCPT ); Sat, 4 Aug 2018 22:56:20 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:59030 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726069AbeHEC4T (ORCPT ); Sat, 4 Aug 2018 22:56:19 -0400 Received: from localhost (unknown [172.58.40.233]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id BBDE814077A41; Sat, 4 Aug 2018 17:53:43 -0700 (PDT) Date: Sat, 04 Aug 2018 17:53:42 -0700 (PDT) Message-Id: <20180804.175342.887624852314321631.davem@davemloft.net> To: dima@arista.com Cc: linux-kernel@vger.kernel.org, natechancellor@gmail.com, herbert@gondor.apana.org.au, steffen.klassert@secunet.com, netdev@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCHv2] netlink: Don't shift on 64 for ngroups From: David Miller In-Reply-To: <20180805003553.11104-1-dima@arista.com> References: <20180805003553.11104-1-dima@arista.com> X-Mailer: Mew version 6.7 on Emacs 26 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sat, 04 Aug 2018 17:53:44 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dmitry Safonov Date: Sun, 5 Aug 2018 01:35:53 +0100 > 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") > Reported-and-Tested-by: Nathan Chancellor > Signed-off-by: Dmitry Safonov Applied and queued up for -stable.