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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 3FD0AC76188 for ; Mon, 22 Jul 2019 14:17:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0F91121911 for ; Mon, 22 Jul 2019 14:17:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gW9vyQD8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728441AbfGVORz (ORCPT ); Mon, 22 Jul 2019 10:17:55 -0400 Received: from mail-io1-f66.google.com ([209.85.166.66]:39475 "EHLO mail-io1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728228AbfGVORz (ORCPT ); Mon, 22 Jul 2019 10:17:55 -0400 Received: by mail-io1-f66.google.com with SMTP id f4so74252015ioh.6 for ; Mon, 22 Jul 2019 07:17:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=8BgcIiKgU3cVL5c3uWuI7qgsPo43Ofan69gI+GtB8pA=; b=gW9vyQD8wpUE67AmtdmO61lNcDOm8C5bBDjVDcn6BwyHFIH8yaSi732bkz4H2nu2+K 0EQKB1Eqsi2bMtqtxkY6Uqvm9FbC3KHdjMr8YWU2Q0dO14s4YHbTce11onLwHo4AkMfY yl+IIgyxsY6GRdnWrYZCAWCuTn9eqfkm+fD2CxNNGY7VToOg0UAD+IT95RBQ3H+H4PRq AYlaAXHtxknXs98faJuayVZB7UpcKc1FZ6sfp2Vz7vFXDf72PzX1oucRO0/NM4yrPteD mACizNGtGqbpG8m6dvzm4d6MjETaOL0ZyGQyV8xUaDMtMLLMbru0xbYgT4Eyb7xT32DO AWqw== 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=8BgcIiKgU3cVL5c3uWuI7qgsPo43Ofan69gI+GtB8pA=; b=SaiCNc7rxVBu4PIqMQZdFJGokwYw8/t845fBmk4LlzuEUpEb3CH6Llusm57ycDqx27 u2O9mATtUnSBojBt1P6oFvVIwJgISz6tkyKzDDc+Iqp9GrVdEyZTK/BDmbm6OHspPXhj cFc+28D/cvwvgKvDbs7oB7sn392zAAY1VTBQcL+R2+MZkDCpQJ2pDclbf6GPga3iOs64 1xqS+FixuZXsN0i3tvMDqfsp++KmBwDjsnBr8zSBgE+nN+oe/t1+OIswLGBe3oMt9xj/ I+Z/sgH3FlwMg7aQ4IWW4EtbJ+V9A0aZup2+RzyezGTQpT13EokVIV0gq2l8NJbyzOnI PLzQ== X-Gm-Message-State: APjAAAU8Mc5HPzlpvJSI8Kb2WbM5DAnOxx8/0lQJTzl+wthaBEAI84VG rmV17qATUSpZxHSiCQhFmihIEHiyjIM/fEpMIU/APIPw X-Google-Smtp-Source: APXvYqxSU8r5SW12WAZvYzgqmo77sEVY1AxWrM0uLeeeouxYv0Rw9/ilnZOqdOmpbDCS0VjqHL/70dpc95EAtETUm4U= X-Received: by 2002:a6b:d008:: with SMTP id x8mr62293510ioa.129.1563805074311; Mon, 22 Jul 2019 07:17:54 -0700 (PDT) MIME-Version: 1.0 References: <20190722132111.25743-1-omosnace@redhat.com> In-Reply-To: <20190722132111.25743-1-omosnace@redhat.com> From: William Roberts Date: Mon, 22 Jul 2019 09:17:42 -0500 Message-ID: Subject: Re: [PATCH] selinux: check sidtab limit before adding a new entry To: Ondrej Mosnacek Cc: selinux@vger.kernel.org, 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 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? > + if (count == SIDTAB_MAX) > + goto out_unlock; > + > /* insert context into new entry */ > rc = -ENOMEM; > dst = sidtab_do_lookup(s, count, 1); > -- > 2.21.0 >