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=-14.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 776F2C3A59F for ; Mon, 26 Aug 2019 17:45:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A4E62184D for ; Mon, 26 Aug 2019 17:45:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="m/a0mTn8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387460AbfHZRpr (ORCPT ); Mon, 26 Aug 2019 13:45:47 -0400 Received: from mail-io1-f67.google.com ([209.85.166.67]:40540 "EHLO mail-io1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387459AbfHZRpr (ORCPT ); Mon, 26 Aug 2019 13:45:47 -0400 Received: by mail-io1-f67.google.com with SMTP id t6so39368112ios.7 for ; Mon, 26 Aug 2019 10:45:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=pU42gGw1gVlVUlF/wW/uAiCaAt/FVvOc/4u8XYPtZ6Q=; b=m/a0mTn8JIle2t4XwbClGaKckf9LvOCHpdQOtGkzUU0rgUZ8S22KXFW8g1bzXRTigd LRdxz5zugcj/G1i+OuzEkIRhO17zMitYulMruQy5JkXpHCG89RN1LywMhCPsUGuVD/rf 0tUvUnBlKrwHT+X2zmLr3/8lQaz7tJQwVrjgZhGdJ36x8/MvvefYoliDLf3Memx7VrkB TyVgQnHkRw5PAIlEsUU8ds+God+tLcZl29vHHkKyDVjspcuYQG6bwL0xGUFNpRy9E+dg PW5adaRX7JBso0vpertu9Oi9ZrkqAkUo6QmK67BhqPOMrN+eg/S5CPh7mMH7o3c0e2G7 XTyg== 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=pU42gGw1gVlVUlF/wW/uAiCaAt/FVvOc/4u8XYPtZ6Q=; b=L9VbI6URnr0jeaMJegb2CTXhv2R4CrI/dmeZ0hF6AzhZvQJKC/CodOEtQPeo1lm41i O+3mh7QqcDesThFTSrHXTDS9w64VgRJD8HgvV7iROH6+Ss3iiuvQLnmQoI8T5NgMeewW dUM94muUDGimDSWLa+JIlpscDA/ov385/1wDizcsHI+to7lEJsotEym8BbABJqML/3fP 3IQGuj0VJvYtbKy/E6dsRYJvXMjypcmvDBHGXjLnC+r1TlNA0GE4PZAxCi1p+A0vBI7z 5dMAAHy88ZvoNgQ1AafUf3b14GPTsbMLmTBNmUm0MB3G8W4/FV3n5LJCyAWf4iyBE/Uo at5A== X-Gm-Message-State: APjAAAXbTVrn6VXuNMngj7frqpT37GpEDkdWq1uBJlYaCvU7q+YJRhQI hMTQixX4PTeBG65j6WgpAmzIlyPqBPHTi7obQeBogg== X-Google-Smtp-Source: APXvYqwOqTkOFbPFSsSZbOULUPv8P8IBKF6ZVFOE7qI6tsIsvWnFBKuVEdlXRjTQSOHCljAxWZogDhucBGlwtm4ztH0= X-Received: by 2002:a6b:c94c:: with SMTP id z73mr27054283iof.84.1566841546578; Mon, 26 Aug 2019 10:45:46 -0700 (PDT) MIME-Version: 1.0 References: <20190826153028.32639-1-pjones@redhat.com> <20190826153028.32639-2-pjones@redhat.com> <20190826163020.e7sahr3irqwwneey@linux.intel.com> In-Reply-To: <20190826163020.e7sahr3irqwwneey@linux.intel.com> From: Matthew Garrett Date: Mon, 26 Aug 2019 10:45:35 -0700 Message-ID: Subject: Re: [PATCH 2/2] efi+tpm: don't traverse an event log with no events To: Jarkko Sakkinen Cc: Peter Jones , Ard Biesheuvel , Roberto Sassu , Bartosz Szczepanek , Lyude Paul , linux-efi , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org On Mon, Aug 26, 2019 at 9:30 AM Jarkko Sakkinen wrote: > > On Mon, Aug 26, 2019 at 11:30:28AM -0400, Peter Jones wrote: > > When there are no entries to put into the final event log, some machines > > will return the template they would have populated anyway. In this case > > the nr_events field is 0, but the rest of the log is just garbage. > > > > This patch stops us from trying to iterate the table with > > __calc_tpm2_event_size() when the number of events in the table is 0. > > > > Signed-off-by: Peter Jones > > Tested-by: Lyude Paul > > --- > > drivers/firmware/efi/tpm.c | 14 +++++++++----- > > 1 file changed, 9 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c > > index 1d3f5ca3eaa..be51ed17c6e 100644 > > --- a/drivers/firmware/efi/tpm.c > > +++ b/drivers/firmware/efi/tpm.c > > @@ -75,11 +75,15 @@ int __init efi_tpm_eventlog_init(void) > > goto out; > > } > > > > - tbl_size = tpm2_calc_event_log_size((void *)efi.tpm_final_log > > - + sizeof(final_tbl->version) > > - + sizeof(final_tbl->nr_events), > > - final_tbl->nr_events, > > - log_tbl->log); > > + tbl_size = 0; > > + if (final_tbl->nr_events != 0) { > > + void *events = (void *)efi.tpm_final_log > > + + sizeof(final_tbl->version) > > + + sizeof(final_tbl->nr_events); > > + tbl_size = tpm2_calc_event_log_size(events, > > + final_tbl->nr_events, > > + log_tbl->log); > > + } > > Reviewed-by: Jarkko Sakkinen Acked-by: Matthew Garrett