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=-9.9 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,USER_AGENT_GIT 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 AD6E6ECE58C for ; Wed, 2 Oct 2019 17:04:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B53E21D82 for ; Wed, 2 Oct 2019 17:04:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="tdnoIcnm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728706AbfJBRD5 (ORCPT ); Wed, 2 Oct 2019 13:03:57 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:39963 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728662AbfJBRD4 (ORCPT ); Wed, 2 Oct 2019 13:03:56 -0400 Received: by mail-wr1-f68.google.com with SMTP id l3so20517630wru.7 for ; Wed, 02 Oct 2019 10:03:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=4a/CPg2xqZ+b/NZpx616PMtohSxll231qGMOuYzcxWE=; b=tdnoIcnmIker0lvF0KY3CO60+cNs1URBTEXXNXeUHW2fshCRDEH9xmYdis8pb1fbyb vNRpKz04Fu+yWrCMZl4FUbI/pJEuRCInVKToqfVtof3VoXvgmrFZtNwmeBWMGXrl00xF FqVum7Wmu5DH4DDvKIL3nYWX00HsxNPaIzDN5jDm0hi91BB0lXTB58XpG5EYQ6fIvWns 3YVbuJarZaqE5M9XLA0CmxLCQ7htEsQld6/RrO2fbgf84bF3w1DL/ozhBDdgqWWWOwyz NsAL2C7i/UyXnd35g6XPDzPh2xyrhVXOtrhyCG/WpIOwdMbI5nzYR9ztd3wtLNA46vQj HAUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=4a/CPg2xqZ+b/NZpx616PMtohSxll231qGMOuYzcxWE=; b=GXrzt9sA4hHawaA8PIg5YUYikBdsD+KRDqCgNd52x58wEXudYGBjgdNnKf1c+q71Fu Hw1HBvgrHMBczol+G7ciVM4lpqHjWIT6iB+r7a4E7SPVAUvOtoshBS6cdhGQx69j9tsK xZfUD2WZ0GYNR+a5VtX5MAfw//lR9bCnOJXF5tczt60kVy6rpbSIxNiNc8sTBKNLPLqD bGCvh3sZ7OtYF5MXQvEc/BMTP39QcL0zDOU/7q5OoJADx1ZPlj6I4DyWiA5J53K54vS7 nCQoU1mgHeetMNxP/qXYQinai4LtG+tKkY0h6A6j9rQAGr+KlVwwim7U3UmP9qrjUt2a SnuQ== X-Gm-Message-State: APjAAAXVoknTgsw9kCIVElVc6nstPiIteW1GjuSnwmlnxGA7QA+i96Q2 xFLjFQ325r6Sz0Z9JaqWSJUsHjEODik6WFhy X-Google-Smtp-Source: APXvYqzYraTwzohAp1cOr3JZijdPGRhdWNVm7YqHKQHJV7nNyafLy7wTF+k2v7yiQ67qhfcMavJB8Q== X-Received: by 2002:adf:e849:: with SMTP id d9mr3616348wrn.358.1570035834376; Wed, 02 Oct 2019 10:03:54 -0700 (PDT) Received: from sudo.home ([2a01:cb1d:112:6f00:f145:3252:fc29:76c9]) by smtp.gmail.com with ESMTPSA id f18sm7085459wmh.43.2019.10.02.10.03.53 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 02 Oct 2019 10:03:53 -0700 (PDT) From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-kernel@vger.kernel.org, Ben Dooks , Dave Young , Jarkko Sakkinen , Jerry Snitselaar , linux-integrity@vger.kernel.org, Lukas Wunner , Lyude Paul , Matthew Garrett , Octavian Purdila , Peter Jones , Scott Talbert Subject: [PATCH 4/7] efi/tpm: don't traverse an event log with no events Date: Wed, 2 Oct 2019 18:59:01 +0200 Message-Id: <20191002165904.8819-5-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191002165904.8819-1-ard.biesheuvel@linaro.org> References: <20191002165904.8819-1-ard.biesheuvel@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Peter Jones 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. Fixes: c46f3405692d ("tpm: Reserve the TPM final events table") Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Peter Jones Tested-by: Lyude Paul Reviewed-by: Jarkko Sakkinen Acked-by: Matthew Garrett Acked-by: Ard Biesheuvel Signed-off-by: Jarkko Sakkinen Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/tpm.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c index 1d3f5ca3eaaf..b9ae5c6f9b9c 100644 --- a/drivers/firmware/efi/tpm.c +++ b/drivers/firmware/efi/tpm.c @@ -75,11 +75,16 @@ 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); + } memblock_reserve((unsigned long)final_tbl, tbl_size + sizeof(*final_tbl)); early_memunmap(final_tbl, sizeof(*final_tbl)); -- 2.20.1