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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 E3AF9C76188 for ; Tue, 23 Jul 2019 06:48:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B4E462238E for ; Tue, 23 Jul 2019 06:48:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730533AbfGWGsY (ORCPT ); Tue, 23 Jul 2019 02:48:24 -0400 Received: from mail-ot1-f67.google.com ([209.85.210.67]:36606 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729552AbfGWGsY (ORCPT ); Tue, 23 Jul 2019 02:48:24 -0400 Received: by mail-ot1-f67.google.com with SMTP id r6so42953614oti.3 for ; Mon, 22 Jul 2019 23:48:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=cY5YICyEZTZmKAe8S+z84IVZKH+kurb4pXia9o6wuCY=; b=npPyA4MaNm/pE1HOKC/P/Z7wcOUg5RfPNrgeOawJvn1Nejjo9EQSSWN54xYMSxjU1f MbayM6LdJdM0kNh2eDdSMXuqxa7npaG0+ee/Lor1qhn7uMymyLAMcnsgLC/Uf/gvoCsJ Ulo2gGOI1CgG4SQU50nw1XiZg5k0IOUySvpOsBG5wz34J2wke6HjP+D8ZQZl39oiCmPj IdkVZWN/I5/HD3f4B47YUezWY0Yr7Z6OhPVwFPVBsep6sYCqV/zsHafTw+LSUwc4Cw30 BUJS0P3Y+6kRLa6n5xp4XwD0BLVrCn/tEGEJhWVIJzl0OrpwQMcFN6Mx3aFkBjE1UnDW 4aeQ== X-Gm-Message-State: APjAAAXMnWZH7qZkbKnhn/NLxy61zzvsEKei+C04Mr/PUXvLcNPJ8FTc DhugYCcqoco8Xgeu/9SdEHj+d/ZPfK1lidlyVmU2Rewm X-Google-Smtp-Source: APXvYqxsddQYVNqohu4Jb847ypd+7U9vUJnysW3/+0Sp9QkhauBUew6rE6lNs/w8PcqsF2R2eim5RvqRMoXbKMYvJEE= X-Received: by 2002:a9d:73cd:: with SMTP id m13mr20394988otk.43.1563864503462; Mon, 22 Jul 2019 23:48:23 -0700 (PDT) MIME-Version: 1.0 References: <20190722132111.25743-1-omosnace@redhat.com> In-Reply-To: From: Ondrej Mosnacek Date: Tue, 23 Jul 2019 08:48:12 +0200 Message-ID: Subject: Re: [PATCH] selinux: check sidtab limit before adding a new entry To: William Roberts Cc: SElinux list , Paul Moore , NitinGote , kernel-hardening@lists.openwall.com, Kees Cook Content-Type: text/plain; charset="UTF-8" Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org On Mon, Jul 22, 2019 at 4:17 PM William Roberts wrote: > On Mon, Jul 22, 2019 at 8:34 AM Ondrej Mosnacek wrote: > > > > We need to error out when trying to add an entry above SIDTAB_MAX in > > sidtab_reverse_lookup() to avoid overflow on the odd chance that this > > happens. > > > > Fixes: ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve performance") > > Signed-off-by: Ondrej Mosnacek > > --- > > security/selinux/ss/sidtab.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c > > index e63a90ff2728..54c1ba1e79ab 100644 > > --- a/security/selinux/ss/sidtab.c > > +++ b/security/selinux/ss/sidtab.c > > @@ -286,6 +286,11 @@ static int sidtab_reverse_lookup(struct sidtab *s, struct context *context, > > ++count; > > } > > > > + /* bail out if we already reached max entries */ > > + rc = -ENOMEM; > > Wouldn't -EOVERFLOW be better? Good point. Will change it in v2. > > > + if (count == SIDTAB_MAX) > > + goto out_unlock; > > + > > /* insert context into new entry */ > > rc = -ENOMEM; > > dst = sidtab_do_lookup(s, count, 1); > > -- > > 2.21.0 > > Thanks, -- Ondrej Mosnacek Software Engineer, Security Technologies Red Hat, Inc.