From patchwork Mon Oct 12 08:36:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11831921 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 A5A3F16BC for ; Mon, 12 Oct 2020 08:36:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 880282145D for ; Mon, 12 Oct 2020 08:36:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602491804; bh=xGcSgxMYQFxatWCkytqqmruYRAdLAQg4c++Ihzfeilk=; h=From:To:Cc:Subject:Date:List-ID:From; b=tX8pg3AyKG03J/LPiuLR40M/XrepgBeaq54Oh2Ne8PLpTrn9spmqS0cz1Kh4YwLlH m/J0gqNl7MBemLiJJRxAztVJivnsSkHFvuak6gVMmfR+ef6uU1Qa6njL7QfB7snCcQ ut8U/glpnTOEGn/BxQ449dw/Ecbazu7Y1TuHYwT8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726335AbgJLIgo (ORCPT ); Mon, 12 Oct 2020 04:36:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:57714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726104AbgJLIgn (ORCPT ); Mon, 12 Oct 2020 04:36:43 -0400 Received: from e123331-lin.nice.arm.com (lfbn-nic-1-188-42.w2-15.abo.wanadoo.fr [2.15.37.42]) (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 3A12B20714; Mon, 12 Oct 2020 08:36:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602491803; bh=xGcSgxMYQFxatWCkytqqmruYRAdLAQg4c++Ihzfeilk=; h=From:To:Cc:Subject:Date:From; b=bPmPBhsiqQe/SZalLiOr6kMou1sPqsknAquA/3ICQz/fvbGe+NAiqnOKRNyekagSF 7wtZRPFd6l0AOUH5qxtDcsAi4pbXb+AT6Fr010MvyvLoKBmzZtnmAKV3t/4yrzodUw kX7eT2VZ/6i2icJJWPo90BGu4reJThTOWQZLl/w8= From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, Ard Biesheuvel , Chester Lin , Mimi Zohar , Dmitry Kasatkin , James Morris , "Serge E. Hallyn" Subject: [PATCH] ima: defer arch_ima_get_secureboot() call to IMA init time Date: Mon, 12 Oct 2020 10:36:31 +0200 Message-Id: <20201012083631.12724-1-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Chester reports that it is necessary to introduce a new way to pass the EFI secure boot status between the EFI stub and the core kernel on ARM systems. The usual way of obtaining this information is by checking the SecureBoot and SetupMode EFI variables, but this can only be done after the EFI variable workqueue is created, which occurs in a subsys_initcall(), whereas arch_ima_get_secureboot() is called much earlier by the IMA framework. However, the IMA framework itself is started as a late_initcall, and the only reason the call to arch_ima_get_secureboot() occurs so early is because it happens in the context of a __setup() callback that parses the ima_appraise= command line parameter. So let's refactor this code a little bit, by using a core_param() callback to capture the command line argument, and deferring any reasoning based on its contents to the IMA init routine. Cc: Chester Lin Cc: Mimi Zohar Cc: Dmitry Kasatkin Cc: James Morris Cc: "Serge E. Hallyn" Link: https://lore.kernel.org/linux-arm-kernel/20200904072905.25332-2-clin@suse.com/ Signed-off-by: Ard Biesheuvel --- include/linux/ima.h | 6 +++++ security/integrity/ima/ima_appraise.c | 24 +++++++++++--------- security/integrity/ima/ima_main.c | 1 + 3 files changed, 20 insertions(+), 11 deletions(-) diff --git a/include/linux/ima.h b/include/linux/ima.h index d15100de6cdd..8aefee9c36ab 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -27,6 +27,12 @@ extern void ima_post_path_mknod(struct dentry *dentry); extern int ima_file_hash(struct file *file, char *buf, size_t buf_size); extern void ima_kexec_cmdline(int kernel_fd, const void *buf, int size); +#ifdef CONFIG_IMA_APPRAISE_BOOTPARAM +extern void ima_appraise_parse_cmdline(void); +#else +static inline void ima_appraise_parse_cmdline(void) {} +#endif + #ifdef CONFIG_IMA_KEXEC extern void ima_add_kexec_buffer(struct kimage *image); #endif diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index b8848f53c8cc..a0135dbf2a64 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -16,26 +16,28 @@ #include "ima.h" -static int __init default_appraise_setup(char *str) -{ #ifdef CONFIG_IMA_APPRAISE_BOOTPARAM +static char *ima_appraise_cmdline_default __initdata; +core_param(ima_appraise, ima_appraise_cmdline_default, charp, 0); + +void __init ima_appraise_parse_cmdline(void) +{ + if (!ima_appraise_cmdline_default) + return; if (arch_ima_get_secureboot()) { pr_info("Secure boot enabled: ignoring ima_appraise=%s boot parameter option", - str); - return 1; + ima_appraise_cmdline_default); + return; } - if (strncmp(str, "off", 3) == 0) + if (strncmp(ima_appraise_cmdline_default, "off", 3) == 0) ima_appraise = 0; - else if (strncmp(str, "log", 3) == 0) + else if (strncmp(ima_appraise_cmdline_default, "log", 3) == 0) ima_appraise = IMA_APPRAISE_LOG; - else if (strncmp(str, "fix", 3) == 0) + else if (strncmp(ima_appraise_cmdline_default, "fix", 3) == 0) ima_appraise = IMA_APPRAISE_FIX; -#endif - return 1; } - -__setup("ima_appraise=", default_appraise_setup); +#endif /* * is_ima_appraise_enabled - return appraise status diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 8a91711ca79b..31d72cf04768 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -850,6 +850,7 @@ static int __init init_ima(void) { int error; + ima_appraise_parse_cmdline(); ima_init_template_list(); hash_setup(CONFIG_IMA_DEFAULT_HASH); error = ima_init();