From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6D183288CC; Sun, 20 Apr 2025 12:33:15 +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=1745152397; cv=none; b=G/ws4gju+xVaI2D2qjfn0yVsChE+dqVSffqG5yLxAOM5vnpOsZtVhE0N8/0cccsjWInP0/ow3vK9B0mlM5c1SCzVdlbCqmfItEUvKBY1u8eQuIPluHvwntKADzA4VL+ApvDby47PkZExaW6/nC4hsS7euM2COfucSsNwVGMMn0I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745152397; c=relaxed/simple; bh=QCMs88tF/w+2GynbSwK5b75+viaCr7sRkqq58kGoZkw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=dIbV6D0jhfXXK/KL57bIW0tb3Kuj+k2INgID1NU/mh5Lx8ffBgwOCFmjhxKm5grhaJMEGKgHgWRcljyiFZnrxa54ABGqvubQaK4Xdrzjh+ZJEZ07Tk9M3hnzHO+9gpT9hbceITvoPqR/q2cXTte/k52kMt9Qx60dWJGZOy3PnaY= 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=bXWMcxxe; 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="bXWMcxxe" Received: from [100.70.200.26] (unknown [20.114.144.49]) by linux.microsoft.com (Postfix) with ESMTPSA id 077892052525; Sun, 20 Apr 2025 05:33:12 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 077892052525 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1745152395; bh=np2gxTjaHDpb1rtQXoHJcdS3uyHNDSp77IUqwm4GRBs=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=bXWMcxxeSTBTuvhzky/PK/kzwiTKenzUefcYBTl40OvexVFJ34QfeeXJWhmErVzrF URG/kDn+nEc6SjsPehefverHc4IrfRRLD2gNlmV4/h/SUvvAdBbn0719UhQfx3nAcG rREeBW6sTr2HEXjlNli8RsW0B+svH1w1pJuv4+Do= Message-ID: <6a4ecd66-4249-476c-87fa-b5a3806fae5e@linux.microsoft.com> Date: Sun, 20 Apr 2025 05:33:10 -0700 Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v12 5/9] ima: kexec: define functions to copy IMA log at soft boot To: Baoquan He Cc: 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, madvenka@linux.microsoft.com, nramas@linux.microsoft.com, James.Bottomley@hansenpartnership.com, vgoyal@redhat.com, dyoung@redhat.com References: <20250416021028.1403-1-chenste@linux.microsoft.com> <20250416021028.1403-6-chenste@linux.microsoft.com> Content-Language: en-US From: steven chen In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/18/2025 12:40 AM, Baoquan He wrote: > On 04/15/25 at 07:10pm, steven chen wrote: >> From: Steven Chen >> >> The IMA log is currently copied to the new kernel during kexec 'load' >> using ima_dump_measurement_list(). However, the log copied at kexec >> 'load' may result in loss of IMA measurements that only occurred after >> kexec "load'. 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 >> kexec 'execute'. >> >> Set the priority of register_reboot_notifier to INT_MIN to ensure that the >> IMA log copy operation will happen at the end of the operation chain, so >> that all the IMA measurement records extended into the TPM are copied >> >> Signed-off-by: Tushar Sugandhi > ^^^ > > The tag Hi Baoquan, I will add Co-developed-by tag in next version. Thanks, Steven >> Cc: Eric Biederman >> Cc: Baoquan He >> Cc: Vivek Goyal >> Cc: Dave Young >> Signed-off-by: Steven Chen >> Reviewed-by: Mimi Zohar >> --- >> include/linux/ima.h | 3 ++ >> security/integrity/ima/ima_kexec.c | 47 ++++++++++++++++++++++++++++++ >> 2 files changed, 50 insertions(+) > Other than the tag, this looks good to me: > > Acked-by: Baoquan He > >> 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 7e0a19c3483f..e79f6caf895b 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 bool ima_kexec_update_registered; >> static struct seq_file ima_kexec_file; >> +static void *ima_kexec_buffer; >> >> static void ima_free_kexec_file_buf(struct seq_file *sf) >> { >> @@ -162,6 +166,49 @@ 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 = { >> + .notifier_call = ima_update_kexec_buffer, >> + .priority = INT_MIN >> +}; >> + >> +/* >> + * 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 */ >> >> /* >> -- >> 2.43.0 >>