From nobody Fri Dec 19 21:47:28 2025 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id EABB114900F; Tue, 18 Mar 2025 01:05:17 +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=1742259919; cv=none; b=eEbjaOhE4tXjdPqIuzwNe+YztUL8SsHEKzCiO3tNYsLa9LDwJu0JkgCThTZo1Yej7tenq9hniJ0oWt+Fs4QLckm+hBKFwgoCQ5Hm0amltBTPzZzqDOtKafTRmFVFkfREUl0orSTg1el2BWIzQOTUccSqGdLXKmzHXqJJKSS5jAA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742259919; c=relaxed/simple; bh=5nZEY0j7i8mG4u8/1CGV9wSIM5zPgjiJtsL7mh9u+14=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=heDk5UYLluHmNSFxFr1XQD4M6cB9bkyta7ufzck+PpUVlBVogxKjlQRjTJtk0epcYY8k4NqpPcZfJsAg2600kH4RPD+xSj3PyjXyAXAu8bOZ5QtdOrxFm7D4q/sldxbVtDD59F/OLTP+Crn2O4BuGEnaG7tgRMV3fntS8xo9yVA= 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=jbwYYcq3; 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="jbwYYcq3" Received: from localhost.localdomain (unknown [131.107.147.236]) by linux.microsoft.com (Postfix) with ESMTPSA id 9CBC420DEACD; Mon, 17 Mar 2025 18:05:16 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 9CBC420DEACD DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1742259916; bh=IW0Tu0Ypw9GySYV1UEKgWFwAzFcQAPCZdi7ximAPf+k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jbwYYcq3e97cftHkYSAVt3lU/Dj/B8sjz4cZGM2uYIqNGl2qNuFCtIeTHHXgPIRaZ IKNJclGefNBl9okI8i70sKcBeolZid1rXmm9hIBVDNU+vAlfF9w3aeV+47qbMRt65E PeadlIkzXZQO4H0N4liWWeS75PH0MXgyJQlXZfo0= 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 Cc: madvenka@linux.microsoft.com, nramas@linux.microsoft.com, James.Bottomley@HansenPartnership.com, bhe@redhat.com, vgoyal@redhat.com, dyoung@redhat.com Subject: [PATCH v10 5/8] ima: kexec: define functions to copy IMA log at soft boot Date: Mon, 17 Mar 2025 18:04:43 -0700 Message-ID: <20250318010448.954-6-chenste@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250318010448.954-1-chenste@linux.microsoft.com> References: <20250318010448.954-1-chenste@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The IMA log is currently copied to the new kernel during kexec 'load'=20 using ima_dump_measurement_list(). However, the log copied at kexec=20 'load' may result in loss of IMA measurements that only occurred after kexec "load'. Therefore, the log needs to be copied during kexec=20 '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=20 Kernel image has been loaded for kexec. ima_kexec_post_load() maps the=20 IMA buffer to a segment in the newly loaded Kernel. It also registers=20 the reboot notifier_block to trigger ima_update_kexec_buffer() at=20 kexec 'execute'. Signed-off-by: Tushar Sugandhi Cc: Eric Biederman Cc: Baoquan He =20 Cc: Vivek Goyal Cc: Dave Young Signed-off-by: steven chen Reviewed-by: Stefan Berger Signed-off-by: steven chen --- include/linux/ima.h | 3 ++ security/integrity/ima/ima_kexec.c | 47 ++++++++++++++++++++++++++++++ 2 files changed, 50 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) {} =20 #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 =20 #else diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/im= a_kexec.c index 34020b1513b0..9336c4f60650 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" =20 #ifdef CONFIG_IMA_KEXEC +static bool ima_kexec_update_registered; static struct seq_file ima_kexec_file; +static void *ima_kexec_buffer; =20 static void ima_reset_kexec_file(struct seq_file *sf) { @@ -191,6 +195,49 @@ 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; +} + +static struct notifier_block update_buffer_nb =3D { + .notifier_call =3D ima_update_kexec_buffer, + .priority =3D 1, +}; + +/* + * 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 =3D NULL; + } + + if (!image->ima_buffer_addr) + return; + + ima_kexec_buffer =3D 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 =3D true; + } +} + #endif /* IMA_KEXEC */ =20 /* --=20 2.25.1