From patchwork Sun May 17 12:57:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11554155 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 37BA414B7 for ; Sun, 17 May 2020 12:59:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 208FD20735 for ; Sun, 17 May 2020 12:59:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589720346; bh=K4bW9SUbhJFwMKYXQlU1RiO8Sw6g6tGuIMcVLffkWtQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FEdUAUDnEHbdysgXyeDz5vLTEvSr9f6x42LoQF2qaj0U26j+XEofdM/1k2Mf7f5mG VvBTFd2FBmHMFfmeMmGbII5BdPrw+GcZYdCTT0/eCSiIMVEJS0bb5mN4y8YLX88bcc GdNQpPcACwI6tQ5H+R9U1peKWX6w6n+SWf+czZB4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728111AbgEQM7C (ORCPT ); Sun, 17 May 2020 08:59:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:52090 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728035AbgEQM7C (ORCPT ); Sun, 17 May 2020 08:59:02 -0400 Received: from e123331-lin.nice.arm.com (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 57FEC204EC; Sun, 17 May 2020 12:58:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589720341; bh=K4bW9SUbhJFwMKYXQlU1RiO8Sw6g6tGuIMcVLffkWtQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=18z8pliLqz4DFmOz9J9BnY3COarwmndS4ufpOhNNlGWHJCAL/O4I7tbGdc2Jqp+ZI pgolYbCZG9MVlLz39aLLLZhL+JouD7SH2Ot+n3aAMdbFCzoGMCnYl0bo08ZcGA8dH/ n9BOSSHYbE9UG3DOTmMwS9ZeZ1+iEdFHrtjsW794= From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-kernel@vger.kernel.org, Arvind Sankar , Benjamin Thiel , Borislav Petkov , Dave Young , Heinrich Schuchardt , Javier Martinez Canillas , Jerry Snitselaar , Lenny Szubowicz , linux-acpi@vger.kernel.org, Loic Yhuel , Matthew Garrett , Mike Lothian , Punit Agrawal Subject: [PATCH 7/7] tpm: check event log version before reading final events Date: Sun, 17 May 2020 14:57:54 +0200 Message-Id: <20200517125754.8934-8-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200517125754.8934-1-ardb@kernel.org> References: <20200517125754.8934-1-ardb@kernel.org> MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Loic Yhuel This fixes the boot issues since 5.3 on several Dell models when the TPM is enabled. Depending on the exact grub binary, booting the kernel would freeze early, or just report an error parsing the final events log. We get an event log in the SHA-1 format, which doesn't have a tcg_efi_specid_event_head in the first event, and there is a final events table which doesn't match the crypto agile format. __calc_tpm2_event_size reads bad "count" and "efispecid->num_algs", and either fails, or loops long enough for the machine to be appear frozen. So we now only parse the final events table, which is per the spec always supposed to be in the crypto agile format, when we got a event log in this format. Fixes: c46f3405692de ("tpm: Reserve the TPM final events table") Fixes: 166a2809d65b2 ("tpm: Don't duplicate events from the final event log in the TCG2 log") Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1779611 Signed-off-by: Loïc Yhuel Link: https://lore.kernel.org/r/20200512040113.277768-1-loic.yhuel@gmail.com Reviewed-by: Javier Martinez Canillas Reviewed-by: Jerry Snitselaar Reviewed-by: Matthew Garrett [ardb: warn when final events table is missing or in the wrong format] Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/tpm.c | 5 +++-- drivers/firmware/efi/tpm.c | 5 ++++- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c index 1d59e103a2e3..e9a684637b70 100644 --- a/drivers/firmware/efi/libstub/tpm.c +++ b/drivers/firmware/efi/libstub/tpm.c @@ -54,7 +54,7 @@ void efi_retrieve_tpm2_eventlog(void) efi_status_t status; efi_physical_addr_t log_location = 0, log_last_entry = 0; struct linux_efi_tpm_eventlog *log_tbl = NULL; - struct efi_tcg2_final_events_table *final_events_table; + struct efi_tcg2_final_events_table *final_events_table = NULL; unsigned long first_entry_addr, last_entry_addr; size_t log_size, last_entry_size; efi_bool_t truncated; @@ -127,7 +127,8 @@ void efi_retrieve_tpm2_eventlog(void) * Figure out whether any events have already been logged to the * final events structure, and if so how much space they take up */ - final_events_table = get_efi_config_table(LINUX_EFI_TPM_FINAL_LOG_GUID); + if (version == EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) + final_events_table = get_efi_config_table(LINUX_EFI_TPM_FINAL_LOG_GUID); if (final_events_table && final_events_table->nr_events) { struct tcg_pcr_event2_head *header; int offset; diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c index 31f9f0e369b9..0543fbf60222 100644 --- a/drivers/firmware/efi/tpm.c +++ b/drivers/firmware/efi/tpm.c @@ -62,8 +62,11 @@ int __init efi_tpm_eventlog_init(void) tbl_size = sizeof(*log_tbl) + log_tbl->size; memblock_reserve(efi.tpm_log, tbl_size); - if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) + if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR || + log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) { + pr_warn(FW_BUG "TPM Final Events table missing or invalid\n"); goto out; + } final_tbl = early_memremap(efi.tpm_final_log, sizeof(*final_tbl));