From patchwork Mon Mar 1 16:11:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 389914 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5366EC41620 for ; Mon, 1 Mar 2021 17:39:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A2C2652E7 for ; Mon, 1 Mar 2021 17:39:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238859AbhCARjK (ORCPT ); Mon, 1 Mar 2021 12:39:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:54064 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238266AbhCARb5 (ORCPT ); Mon, 1 Mar 2021 12:31:57 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 07E226509F; Mon, 1 Mar 2021 16:52:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614617568; bh=Kuhto6sw57J0J5NpJjFT2cN/PltugDmj6g/k+4xWY0U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kKLLTRQo98mWj4Mpj0dpRWyGZKpYwg10KEUujeE48xtsoXe9uWsBStFI6n+Gechav FJlkiubIxeqgGKSIq+CpN7I0D0uQGvzyDfAZ0EgkPF5+zYSA817dArQ2EO+SxQPVys IMEIaUCUoiAmdLEl1dWIQii6CXaTZI8YewmOHMi8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lakshmi Ramasubramanian , Tyler Hicks , Thiago Jung Bauermann , Mimi Zohar , Sasha Levin Subject: [PATCH 5.4 119/340] ima: Free IMA measurement buffer after kexec syscall Date: Mon, 1 Mar 2021 17:11:03 +0100 Message-Id: <20210301161054.198372880@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161048.294656001@linuxfoundation.org> References: <20210301161048.294656001@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Lakshmi Ramasubramanian [ Upstream commit f31e3386a4e92ba6eda7328cb508462956c94c64 ] IMA allocates kernel virtual memory to carry forward the measurement list, from the current kernel to the next kernel on kexec system call, in ima_add_kexec_buffer() function. This buffer is not freed before completing the kexec system call resulting in memory leak. Add ima_buffer field in "struct kimage" to store the virtual address of the buffer allocated for the IMA measurement list. Free the memory allocated for the IMA measurement list in kimage_file_post_load_cleanup() function. Signed-off-by: Lakshmi Ramasubramanian Suggested-by: Tyler Hicks Reviewed-by: Thiago Jung Bauermann Reviewed-by: Tyler Hicks Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list") Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin --- include/linux/kexec.h | 5 +++++ kernel/kexec_file.c | 5 +++++ security/integrity/ima/ima_kexec.c | 2 ++ 3 files changed, 12 insertions(+) diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 1776eb2e43a44..a1cffce3de8cd 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -293,6 +293,11 @@ struct kimage { /* Information for loading purgatory */ struct purgatory_info purgatory_info; #endif + +#ifdef CONFIG_IMA_KEXEC + /* Virtual address of IMA measurement buffer for kexec syscall */ + void *ima_buffer; +#endif }; /* kexec interface functions */ diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 79f252af7dee3..4e74db89bd23f 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -165,6 +165,11 @@ void kimage_file_post_load_cleanup(struct kimage *image) vfree(pi->sechdrs); pi->sechdrs = NULL; +#ifdef CONFIG_IMA_KEXEC + vfree(image->ima_buffer); + image->ima_buffer = NULL; +#endif /* CONFIG_IMA_KEXEC */ + /* See if architecture has anything to cleanup post load */ arch_kimage_file_post_load_cleanup(image); diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c index 37b1244e3a166..955e4b4d09e21 100644 --- a/security/integrity/ima/ima_kexec.c +++ b/security/integrity/ima/ima_kexec.c @@ -130,6 +130,8 @@ void ima_add_kexec_buffer(struct kimage *image) return; } + image->ima_buffer = kexec_buffer; + pr_debug("kexec measurement buffer for the loaded kernel at 0x%lx.\n", kbuf.mem); }