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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 B2B03C2B9F9 for ; Mon, 10 May 2021 11:41:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99AC6611C2 for ; Mon, 10 May 2021 11:41:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240832AbhEJLgo (ORCPT ); Mon, 10 May 2021 07:36:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:41732 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233312AbhEJKwQ (ORCPT ); Mon, 10 May 2021 06:52:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 35FAD6186A; Mon, 10 May 2021 10:41:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620643263; bh=Jt5EiUEh7mJTWxku/OtT7jTesUR66OVrgO5rF0CQvAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t+5nsvqV1PmqLnLIFFoPy8nFs/SK6XzF9+HPVp1TpdGINBsStGDR6lMOsKfqzZkX7 QF7ZnefvbVHVbxwNVJkyQ6cRu8Ze84xZbg+NmbHQhrzAnI+HuVbTXHghZ6rrD/YpEO Iqmniz00vcnm6Qr/yCQrvVUuhKTtiJvL7Iwnokhc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefan Berger , Jarkko Sakkinen Subject: [PATCH 5.10 245/299] tpm: efi: Use local variable for calculating final log size Date: Mon, 10 May 2021 12:20:42 +0200 Message-Id: <20210510102013.049951750@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102004.821838356@linuxfoundation.org> References: <20210510102004.821838356@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stefan Berger commit 48cff270b037022e37835d93361646205ca25101 upstream. When tpm_read_log_efi is called multiple times, which happens when one loads and unloads a TPM2 driver multiple times, then the global variable efi_tpm_final_log_size will at some point become a negative number due to the subtraction of final_events_preboot_size occurring each time. Use a local variable to avoid this integer underflow. The following issue is now resolved: Mar 8 15:35:12 hibinst kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Mar 8 15:35:12 hibinst kernel: Workqueue: tpm-vtpm vtpm_proxy_work [tpm_vtpm_proxy] Mar 8 15:35:12 hibinst kernel: RIP: 0010:__memcpy+0x12/0x20 Mar 8 15:35:12 hibinst kernel: Code: 00 b8 01 00 00 00 85 d2 74 0a c7 05 44 7b ef 00 0f 00 00 00 c3 cc cc cc 66 66 90 66 90 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 f3 a4 Mar 8 15:35:12 hibinst kernel: RSP: 0018:ffff9ac4c0fcfde0 EFLAGS: 00010206 Mar 8 15:35:12 hibinst kernel: RAX: ffff88f878cefed5 RBX: ffff88f878ce9000 RCX: 1ffffffffffffe0f Mar 8 15:35:12 hibinst kernel: RDX: 0000000000000003 RSI: ffff9ac4c003bff9 RDI: ffff88f878cf0e4d Mar 8 15:35:12 hibinst kernel: RBP: ffff9ac4c003b000 R08: 0000000000001000 R09: 000000007e9d6073 Mar 8 15:35:12 hibinst kernel: R10: ffff9ac4c003b000 R11: ffff88f879ad3500 R12: 0000000000000ed5 Mar 8 15:35:12 hibinst kernel: R13: ffff88f878ce9760 R14: 0000000000000002 R15: ffff88f77de7f018 Mar 8 15:35:12 hibinst kernel: FS: 0000000000000000(0000) GS:ffff88f87bd00000(0000) knlGS:0000000000000000 Mar 8 15:35:12 hibinst kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Mar 8 15:35:12 hibinst kernel: CR2: ffff9ac4c003c000 CR3: 00000001785a6004 CR4: 0000000000060ee0 Mar 8 15:35:12 hibinst kernel: Call Trace: Mar 8 15:35:12 hibinst kernel: tpm_read_log_efi+0x152/0x1a7 Mar 8 15:35:12 hibinst kernel: tpm_bios_log_setup+0xc8/0x1c0 Mar 8 15:35:12 hibinst kernel: tpm_chip_register+0x8f/0x260 Mar 8 15:35:12 hibinst kernel: vtpm_proxy_work+0x16/0x60 [tpm_vtpm_proxy] Mar 8 15:35:12 hibinst kernel: process_one_work+0x1b4/0x370 Mar 8 15:35:12 hibinst kernel: worker_thread+0x53/0x3e0 Mar 8 15:35:12 hibinst kernel: ? process_one_work+0x370/0x370 Cc: stable@vger.kernel.org Fixes: 166a2809d65b ("tpm: Don't duplicate events from the final event log in the TCG2 log") Signed-off-by: Stefan Berger Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman --- drivers/char/tpm/eventlog/efi.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) --- a/drivers/char/tpm/eventlog/efi.c +++ b/drivers/char/tpm/eventlog/efi.c @@ -17,6 +17,7 @@ int tpm_read_log_efi(struct tpm_chip *ch { struct efi_tcg2_final_events_table *final_tbl = NULL; + int final_events_log_size = efi_tpm_final_log_size; struct linux_efi_tpm_eventlog *log_tbl; struct tpm_bios_log *log; u32 log_size; @@ -66,12 +67,12 @@ int tpm_read_log_efi(struct tpm_chip *ch ret = tpm_log_version; if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR || - efi_tpm_final_log_size == 0 || + final_events_log_size == 0 || tpm_log_version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) goto out; final_tbl = memremap(efi.tpm_final_log, - sizeof(*final_tbl) + efi_tpm_final_log_size, + sizeof(*final_tbl) + final_events_log_size, MEMREMAP_WB); if (!final_tbl) { pr_err("Could not map UEFI TPM final log\n"); @@ -80,10 +81,18 @@ int tpm_read_log_efi(struct tpm_chip *ch goto out; } - efi_tpm_final_log_size -= log_tbl->final_events_preboot_size; + /* + * The 'final events log' size excludes the 'final events preboot log' + * at its beginning. + */ + final_events_log_size -= log_tbl->final_events_preboot_size; + /* + * Allocate memory for the 'combined log' where we will append the + * 'final events log' to. + */ tmp = krealloc(log->bios_event_log, - log_size + efi_tpm_final_log_size, + log_size + final_events_log_size, GFP_KERNEL); if (!tmp) { kfree(log->bios_event_log); @@ -94,15 +103,19 @@ int tpm_read_log_efi(struct tpm_chip *ch log->bios_event_log = tmp; /* - * Copy any of the final events log that didn't also end up in the - * main log. Events can be logged in both if events are generated + * Append any of the 'final events log' that didn't also end up in the + * 'main log'. Events can be logged in both if events are generated * between GetEventLog() and ExitBootServices(). */ memcpy((void *)log->bios_event_log + log_size, final_tbl->events + log_tbl->final_events_preboot_size, - efi_tpm_final_log_size); + final_events_log_size); + /* + * The size of the 'combined log' is the size of the 'main log' plus + * the size of the 'final events log'. + */ log->bios_event_log_end = log->bios_event_log + - log_size + efi_tpm_final_log_size; + log_size + final_events_log_size; out: memunmap(final_tbl);