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,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 5A81EC2D0BF for ; Fri, 13 Dec 2019 10:04:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20B2F2073D for ; Fri, 13 Dec 2019 10:04:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="Sqme3mDO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726931AbfLMKEV (ORCPT ); Fri, 13 Dec 2019 05:04:21 -0500 Received: from mail-wm1-f68.google.com ([209.85.128.68]:50978 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726895AbfLMKES (ORCPT ); Fri, 13 Dec 2019 05:04:18 -0500 Received: by mail-wm1-f68.google.com with SMTP id a5so5672724wmb.0 for ; Fri, 13 Dec 2019 02:04:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=VXK6UjT3yvQXehTLYa6S1u2sa5BlRdomwa2/Hcjjkmc=; b=Sqme3mDOu29bXcnx3JAe8SM+kNYOjY0c1eOn0jeZhyWGeYUz5rGyQns0Ag7pq/6y+4 kyNlzPph787dZHJXZEiOAQhGqvDODOeUvfLalFGgPiFOIIbTOdaXxqCO4YXJM6O/J8A5 7y+ODXuNB/C6mQD7u8B9P5qd4jMdTwZO/82wv52hSD1gubm9gWP71J3kBDqhi6pnnpca +eMsnw4qmTsvG5PLIGt4gyyUyu8eeJJt0qvL6jGUQfBofpLosscXuEDnqCzV3F3SUx26 ANV1PwSCvLnuSYw3unH3vKxAF87HodZ174wMuHlQoyrwyn7WrIeh517gJIyDMCnxww0g DLDA== 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=VXK6UjT3yvQXehTLYa6S1u2sa5BlRdomwa2/Hcjjkmc=; b=SpOZ/Ph+One6FP4/M7mEuHUwRycgZHMJ13EPSKAiNJDfqhW48R3ofir1kDTB80LKXq vlRiLaSunooSLEwaU42vLAVBCnJoxfXY3JVs82wIrrtuSyxG0UBBat6X4OLllgrPNSaT GLj/et7XTgoVl/61S3KONUFe49mc9JipSVR2mMIDj9pohB9SoM8KcoEWGErWng1nzzMx 1irUAH0/1qwQ/q+xUaMbmT9OlziMLzXyoKVpOgLY9ZGIihWP5raQGng+PdYsruQgA7oF jrOmx+bk9XaJOBx/i75nqDtkF/EG0gk43cjulrlt+WaEUKiRrFJwwTxJgj41mAVD9G0Y T+sg== X-Gm-Message-State: APjAAAUpmIxCI4Nsx3OUR66wBnmkn+ecHnhH+xr8YwjzaeJsMlUAS1bX UgWYEVVUiFP6/PwDnGbPs1h/c/FaKlzpG831dBLjzg== X-Google-Smtp-Source: APXvYqzrrrCcFiuqdvaZaLnkNV6SCoP4uctJu8CpEBW12Wz60eMvE/ICbTcq/LDfsqhURwKKOS2I+ILGE90133ebxOI= X-Received: by 2002:a1c:a795:: with SMTP id q143mr11772299wme.52.1576231456007; Fri, 13 Dec 2019 02:04:16 -0800 (PST) MIME-Version: 1.0 References: <20191213090646.12329-1-jlee@suse.com> <20191213090646.12329-3-jlee@suse.com> <20191213092049.GW22409@linux-l9pv.suse> In-Reply-To: <20191213092049.GW22409@linux-l9pv.suse> From: Ard Biesheuvel Date: Fri, 13 Dec 2019 10:04:14 +0000 Message-ID: Subject: Re: [PATCH 2/2] efi: show error messages only when loading certificates is failed To: Joey Lee Cc: Chun-Yi Lee , Josh Boyer , "Serge E . Hallyn" , Nayna Jain , Mimi Zohar , James Morris , David Howells , linux-efi , Linux Kernel Mailing List , linux-security-module Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 13 Dec 2019 at 10:21, Joey Lee wrote: > > Hi Ard, > > On Fri, Dec 13, 2019 at 09:10:12AM +0000, Ard Biesheuvel wrote: > > On Fri, 13 Dec 2019 at 10:07, Lee, Chun-Yi wrote: > > > > > > When loading certificates list from EFI variables, the error > > > message and efi status code always be emitted to dmesg. It looks > > > ugly: > > > > > > [ 2.335031] Couldn't get size: 0x800000000000000e > > > [ 2.335032] Couldn't get UEFI MokListRT > > > [ 2.339985] Couldn't get size: 0x800000000000000e > > > [ 2.339987] Couldn't get UEFI dbx list > > > > > > This cosmetic patch moved the messages to the error handling code > > > path. And, it also shows the corresponding status string of status > > > code. > > > > > > > So what output do we get after applying this patch when those > > variables don't exist? > > > > A "UEFI:xxxx list was not found" message will be exposed in dmesg > when kernel loglevel be set to debug. Otherwise there have no messages. > OK, that works for me. I take it this will go via the linux-security tree along with 1/2? Acked-by: Ard Biesheuvel > > > Signed-off-by: "Lee, Chun-Yi" > > > --- > > > security/integrity/platform_certs/load_uefi.c | 40 ++++++++++++++------------- > > > 1 file changed, 21 insertions(+), 19 deletions(-) > > > > > > diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c > > > index 81b19c52832b..b6c60fb3fb6c 100644 > > > --- a/security/integrity/platform_certs/load_uefi.c > > > +++ b/security/integrity/platform_certs/load_uefi.c > > > @@ -1,4 +1,5 @@ > > > // SPDX-License-Identifier: GPL-2.0 > > > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > > > > > #include > > > #include > > > @@ -39,7 +40,7 @@ static __init bool uefi_check_ignore_db(void) > > > * Get a certificate list blob from the named EFI variable. > > > */ > > > static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid, > > > - unsigned long *size) > > > + unsigned long *size, const char *source) > > > { > > > efi_status_t status; > > > unsigned long lsize = 4; > > > @@ -48,23 +49,30 @@ static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid, > > > > > > status = efi.get_variable(name, guid, NULL, &lsize, &tmpdb); > > > if (status != EFI_BUFFER_TOO_SMALL) { > > > - pr_err("Couldn't get size: 0x%lx\n", status); > > > - return NULL; > > > + if (status == EFI_NOT_FOUND) { > > > + pr_debug("%s list was not found\n", source); > > > + return NULL; > > > + } > > > + goto err; > > > } > > > > > > db = kmalloc(lsize, GFP_KERNEL); > > > - if (!db) > > > - return NULL; > > > + if (!db) { > > > + status = EFI_OUT_OF_RESOURCES; > > > + goto err; > > > + } > > > > > > status = efi.get_variable(name, guid, NULL, &lsize, db); > > > if (status != EFI_SUCCESS) { > > > kfree(db); > > > - pr_err("Error reading db var: 0x%lx\n", status); > > > - return NULL; > > > + goto err; > > > } > > > > > > *size = lsize; > > > return db; > > > +err: > > > + pr_err("Couldn't get %s list: %s\n", source, efi_status_to_str(status)); > > > + return NULL; > > > } > > > > > > /* > > > @@ -153,10 +161,8 @@ static int __init load_uefi_certs(void) > > > * an error if we can't get them. > > > */ > > > if (!uefi_check_ignore_db()) { > > > - db = get_cert_list(L"db", &secure_var, &dbsize); > > > - if (!db) { > > > - pr_err("MODSIGN: Couldn't get UEFI db list\n"); > > > - } else { > > > + db = get_cert_list(L"db", &secure_var, &dbsize, "UEFI:db"); > > > + if (db) { > > > rc = parse_efi_signature_list("UEFI:db", > > > db, dbsize, get_handler_for_db); > > > if (rc) > > > @@ -166,10 +172,8 @@ static int __init load_uefi_certs(void) > > > } > > > } > > > > > > - mok = get_cert_list(L"MokListRT", &mok_var, &moksize); > > > - if (!mok) { > > > - pr_info("Couldn't get UEFI MokListRT\n"); > > > - } else { > > > + mok = get_cert_list(L"MokListRT", &mok_var, &moksize, "UEFI:MokListRT"); > > > + if (mok) { > > > rc = parse_efi_signature_list("UEFI:MokListRT", > > > mok, moksize, get_handler_for_db); > > > if (rc) > > > @@ -177,10 +181,8 @@ static int __init load_uefi_certs(void) > > > kfree(mok); > > > } > > > > > > - dbx = get_cert_list(L"dbx", &secure_var, &dbxsize); > > > - if (!dbx) { > > > - pr_info("Couldn't get UEFI dbx list\n"); > > > - } else { > > > + dbx = get_cert_list(L"dbx", &secure_var, &dbxsize, "UEFI:dbx"); > > > + if (dbx) { > > > rc = parse_efi_signature_list("UEFI:dbx", > > > dbx, dbxsize, > > > get_handler_for_dbx); > > > -- > > > 2.16.4 > > >