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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9CF2C433EF for ; Tue, 19 Jul 2022 12:26:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234527AbiGSM0T (ORCPT ); Tue, 19 Jul 2022 08:26:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240207AbiGSMYp (ORCPT ); Tue, 19 Jul 2022 08:24:45 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F2924A81A; Tue, 19 Jul 2022 05:09:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 08CEC6177F; Tue, 19 Jul 2022 12:09:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A7192C341D3; Tue, 19 Jul 2022 12:09:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658232557; bh=vjxibplRmYoM5AjjTBzU2tI1aoEEjXJTn1NajLk+/d8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=J2sNmNEL6miIgnVyy1aMirhGIXsiWpMMpuY+2CSDQzB4eTOu4b5a3YP2TQT/fdVAa TaMBpDXxBEoytt9ooNVScNnUCxxVH7jWQy8ZZh6kf0XMVR9IDjfdRF36DVOB6Dt+nY Zm2WkaOK3LchVsD4/KgykkcFx5MgT0EQGxo85sbM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Coiby Xu , Mimi Zohar , Sasha Levin Subject: [PATCH 5.10 065/112] ima: force signature verification when CONFIG_KEXEC_SIG is configured Date: Tue, 19 Jul 2022 13:53:58 +0200 Message-Id: <20220719114632.773018707@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220719114626.156073229@linuxfoundation.org> References: <20220719114626.156073229@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: Coiby Xu [ Upstream commit af16df54b89dee72df253abc5e7b5e8a6d16c11c ] Currently, an unsigned kernel could be kexec'ed when IMA arch specific policy is configured unless lockdown is enabled. Enforce kernel signature verification check in the kexec_file_load syscall when IMA arch specific policy is configured. Fixes: 99d5cadfde2b ("kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE") Reported-and-suggested-by: Mimi Zohar Signed-off-by: Coiby Xu Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin --- arch/x86/kernel/ima_arch.c | 2 ++ include/linux/kexec.h | 6 ++++++ kernel/kexec_file.c | 11 ++++++++++- 3 files changed, 18 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/ima_arch.c b/arch/x86/kernel/ima_arch.c index 7dfb1e808928..bd218470d145 100644 --- a/arch/x86/kernel/ima_arch.c +++ b/arch/x86/kernel/ima_arch.c @@ -88,6 +88,8 @@ const char * const *arch_get_ima_policy(void) if (IS_ENABLED(CONFIG_IMA_ARCH_POLICY) && arch_ima_get_secureboot()) { if (IS_ENABLED(CONFIG_MODULE_SIG)) set_module_sig_enforced(); + if (IS_ENABLED(CONFIG_KEXEC_SIG)) + set_kexec_sig_enforced(); return sb_arch_rules; } return NULL; diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 037192c3a46f..a1f12e959bba 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -442,6 +442,12 @@ static inline int kexec_crash_loaded(void) { return 0; } #define kexec_in_progress false #endif /* CONFIG_KEXEC_CORE */ +#ifdef CONFIG_KEXEC_SIG +void set_kexec_sig_enforced(void); +#else +static inline void set_kexec_sig_enforced(void) {} +#endif + #endif /* !defined(__ASSEBMLY__) */ #endif /* LINUX_KEXEC_H */ diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 2e0f0b3fb9ab..fff11916aba3 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -29,6 +29,15 @@ #include #include "kexec_internal.h" +#ifdef CONFIG_KEXEC_SIG +static bool sig_enforce = IS_ENABLED(CONFIG_KEXEC_SIG_FORCE); + +void set_kexec_sig_enforced(void) +{ + sig_enforce = true; +} +#endif + static int kexec_calculate_store_digests(struct kimage *image); /* @@ -159,7 +168,7 @@ kimage_validate_signature(struct kimage *image) image->kernel_buf_len); if (ret) { - if (IS_ENABLED(CONFIG_KEXEC_SIG_FORCE)) { + if (sig_enforce) { pr_notice("Enforced kernel signature verification failed (%d).\n", ret); return ret; } -- 2.35.1