From patchwork Mon Feb 3 18:45:56 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: steven chen X-Patchwork-Id: 13958058 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id BE24E1CAA8F; Mon, 3 Feb 2025 18:46:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738608370; cv=none; b=RxXRtI4YFzDqjm19BoYNN6YapNIrCh1ZYb8WA9uCGIsB+oCpDc8vpP83LCs+vfZKS2vN9vyQHKL/+PMW0sSG3n+0IeKop5jfomHjrxBWEvuKN+A7R7wTs/qIGZkaeEDBhLncZo7KKodIxzS0i7SmKaoBD+rSwbRGOUtsEiqYRU0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738608370; c=relaxed/simple; bh=EGSzYZ/wUc8bEEIuGyf1CrDl3ntDab0/DRlAcjZi9fE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=rt88RwZW0n7zzLhM0DKzVP/MyFFzmfxbhcROSj07yCOYKbadCcs4o31gnxdPcJsp1FRrtdHIhbtWAVAJHEbiKaoiCnNH1JzI3OJmKcvYcCK96DXrkjTWVtAi/AHyH9Y/KbGFSsTE+wlWHU6z0PGYNXxs3hJAPGzbqXQ+sKOgzLs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=FzlfxyJa; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="FzlfxyJa" Received: from localhost.localdomain (unknown [167.220.59.4]) by linux.microsoft.com (Postfix) with ESMTPSA id 179F9206AB70; Mon, 3 Feb 2025 10:46:06 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 179F9206AB70 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1738608366; bh=VwNfvVLfL00S8Xn+X+PulIftmjpln6BGP2uOmQnQBPE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FzlfxyJa2zYllr2QnQBcoLdC0CJd2zQNRCPlk9beDrawWXl4IIWhKr7/oM619BKiE IrkzHpkJd/xIBnLr8mlIok6P/aGKN+SZnh2m3edC2yPu1Art7qkomLMF/yvXXVZQVA /Fgi7nBD8iPYFddMszNfSHKN+lyyfmWIPHe7NPhU= From: steven chen To: zohar@linux.ibm.com, stefanb@linux.ibm.com, roberto.sassu@huaweicloud.com, roberto.sassu@huawei.com, eric.snowberg@oracle.com, ebiederm@xmission.com, paul@paul-moore.com, code@tyhicks.com, bauermann@kolabnow.com, linux-integrity@vger.kernel.org, kexec@lists.infradead.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, chenste@linux.microsoft.com Cc: madvenka@linux.microsoft.com, nramas@linux.microsoft.com, James.Bottomley@HansenPartnership.com Subject: [PATCH v7 4/7] ima: kexec: define functions to copy IMA log at soft boot Date: Mon, 3 Feb 2025 10:45:56 -0800 Message-Id: <20250203184558.61367-6-chenste@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20250203184558.61367-1-chenste@linux.microsoft.com> References: <20250203184558.61367-1-chenste@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 IMA log is copied to the new Kernel during kexec 'load' using ima_dump_measurement_list(). The log copy at kexec 'load' may result in loss of IMA measurements during kexec soft reboot. It needs to be copied over during kexec 'execute'. Setup the needed infrastructure to move the IMA log copy from kexec 'load' to 'execute'. Define a new IMA hook ima_update_kexec_buffer() as a stub function. It will be used to call ima_dump_measurement_list() during kexec 'execute'. Implement ima_kexec_post_load() function to be invoked after the new Kernel image has been loaded for kexec. ima_kexec_post_load() maps the IMA buffer to a segment in the newly loaded Kernel. It also registers the reboot notifier_block to trigger ima_update_kexec_buffer() at exec 'execute'. Author: Tushar Sugandhi Reviewed-by: Stefan Berger Suggested-by: Mimi Zohar Reviewed-by: "Petr Tesařík" Signed-off-by: Tushar Sugandhi Signed-off-by: steven chen --- include/linux/ima.h | 3 ++ security/integrity/ima/ima_kexec.c | 46 ++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+) diff --git a/include/linux/ima.h b/include/linux/ima.h index 0bae61a15b60..8e29cb4e6a01 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -32,6 +32,9 @@ static inline void ima_appraise_parse_cmdline(void) {} #ifdef CONFIG_IMA_KEXEC extern void ima_add_kexec_buffer(struct kimage *image); +extern void ima_kexec_post_load(struct kimage *image); +#else +static inline void ima_kexec_post_load(struct kimage *image) {} #endif #else diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c index 283860d20521..854b90d34e2d 100644 --- a/security/integrity/ima/ima_kexec.c +++ b/security/integrity/ima/ima_kexec.c @@ -12,10 +12,14 @@ #include #include #include +#include +#include #include "ima.h" #ifdef CONFIG_IMA_KEXEC static struct seq_file ima_kexec_file; +static void *ima_kexec_buffer; +static bool ima_kexec_update_registered; static void ima_reset_kexec_file(struct seq_file *sf) { @@ -185,6 +189,48 @@ void ima_add_kexec_buffer(struct kimage *image) kexec_dprintk("kexec measurement buffer for the loaded kernel at 0x%lx.\n", kbuf.mem); } + +/* + * Called during kexec execute so that IMA can update the measurement list. + */ +static int ima_update_kexec_buffer(struct notifier_block *self, + unsigned long action, void *data) +{ + return NOTIFY_OK; +} + +struct notifier_block update_buffer_nb = { + .notifier_call = ima_update_kexec_buffer, +}; + +/* + * Create a mapping for the source pages that contain the IMA buffer + * so we can update it later. + */ +void ima_kexec_post_load(struct kimage *image) +{ + if (ima_kexec_buffer) { + kimage_unmap_segment(ima_kexec_buffer); + ima_kexec_buffer = NULL; + } + + if (!image->ima_buffer_addr) + return; + + ima_kexec_buffer = kimage_map_segment(image, + image->ima_buffer_addr, + image->ima_buffer_size); + if (!ima_kexec_buffer) { + pr_err("Could not map measurements buffer.\n"); + return; + } + + if (!ima_kexec_update_registered) { + register_reboot_notifier(&update_buffer_nb); + ima_kexec_update_registered = true; + } +} + #endif /* IMA_KEXEC */ /*