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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 CBAAEC282E0 for ; Sat, 20 Apr 2019 00:01:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E71D2183F for ; Sat, 20 Apr 2019 00:01:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iqWDczWr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727542AbfDTABJ (ORCPT ); Fri, 19 Apr 2019 20:01:09 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:36719 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726357AbfDTABG (ORCPT ); Fri, 19 Apr 2019 20:01:06 -0400 Received: by mail-pl1-f196.google.com with SMTP id ck15so3220962plb.3; Fri, 19 Apr 2019 17:01:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=f4IpH+OdorCiIV78MiqY9yn/kZrpDm8mxQw2q8X3OwU=; b=iqWDczWr6v9A7mTL5Zs8v9D/ZrMB5CR2b+TGFVTf75HWr7pVl8f1H9m8FQozFYyx9T P4AVNSJ3KuLxLHAKiJha1xGb1b0JbgmwK2in87wVdfu34QyCR8VJn6EmROJvwqF7n0N0 XsvZazwWEh5rHmzuftE/c134UbXQGo8i8uztLEiMUHJ1WGizoHqHae63iyTlwzG5pk/g qniSOsSF97/hCHYSmbhB6kAWm8rTtQqoekHMh1zJ+GWn/eWj8u6JMqtgioPFuvcpLmwN JID/QxxGqXw3EXQMZK3naIiRQy1hv2V8u5N3135Kl56Lk9YZz09Z237AAg5OXRgTI2fM 3otw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=f4IpH+OdorCiIV78MiqY9yn/kZrpDm8mxQw2q8X3OwU=; b=Cjof8UPxH3b5kfoT9B8LkxHs/IK9AZWJMAyUdr98zcKstBXdDdtcYQ09+29SgFyHkk 15sgOiuojuZlGdKcM+3O2NbiIDsZbnEZ20t7Y9fApP5vCmeQ+QWMsOzoIc5cBY5EMCGU 6KdWL7CGGaHygOq0weJK54Pc4O4iSoemIEcfkKr37Vp0Lucz5M5HBcnn2YXvbQZluew1 xgO3z/mNNSgWPglD5ViEpk2VqID/0+vvw4aTK8l6Rm0CIdnaVh8UPylByzNGzhiXHi+K yUtuuY2c8SIE1aovnwAXaE2A+6GmBztTae/igPffe3/kMP/4i17tidd3IS0n/LGpiMK+ 75AA== X-Gm-Message-State: APjAAAVdNir8BrvuYbcCnzzh0UVmpDkifPh7C1/XRK4vMxhXWNoJRcsX DGnfFexB2vqiGDuzCKMYn1nK9OXq+S4= X-Google-Smtp-Source: APXvYqwAGDaaSmKnVajmO1N6UxWQ4uVxgqriRHSmwjmJGYQTL29kVzcfknvRFEmZMUvALGzrxqn49Q== X-Received: by 2002:a17:902:2927:: with SMTP id g36mr6368660plb.6.1555718465534; Fri, 19 Apr 2019 17:01:05 -0700 (PDT) Received: from prsriva-linux.corp.microsoft.com ([2001:4898:80e8:2:5828:72bc:96ef:ce7c]) by smtp.gmail.com with ESMTPSA id f5sm6699142pgo.75.2019.04.19.17.01.04 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 19 Apr 2019 17:01:04 -0700 (PDT) From: Prakhar Srivastava X-Google-Original-From: Prakhar Srivastava To: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Cc: zohar@linux.vnet.ibm.com, Prakhar Srivastava , Prakhar Srivastava Subject: [PATCHv2] since cmdline args can be same for multiple kexec, log entry hash will collide. Prepend the kernel file name to the cmdline args to distinguish between cmdline args passed to subsequent kexec calls Date: Fri, 19 Apr 2019 17:00:57 -0700 Message-Id: <20190420000057.5222-3-prsriva02@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190420000057.5222-1-prsriva02@gmail.com> References: <20190420000057.5222-1-prsriva02@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Prakhar Srivastava Signed-off-by: Prakhar Srivastava --- since cmdline args can be same for multiple kexec, log entry hash will collide. Prepend the kernel file name to the cmdline args to distinguish between cmdline args passed to subsequent kexec calls kernel/kexec_core.c | 57 +++++++++++++++++++++++++++++++++++++++++ kernel/kexec_file.c | 14 ++++++++-- kernel/kexec_internal.h | 3 +++ 3 files changed, 72 insertions(+), 2 deletions(-) diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index ae1a3ba24df5..97b77c780311 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -1151,3 +1151,60 @@ void __weak arch_kexec_protect_crashkres(void) void __weak arch_kexec_unprotect_crashkres(void) {} + +/** + * kexec_cmdline_prepend_img_name - prepare the buffer with cmdline + * that needs to be measured + * @outbuf - out buffer that contains the formated string + * @kernel_fd - the file identifier for the kerenel image + * @cmdline_ptr - ptr to the cmdline buffer + * @cmdline_len - len of the buffer. + * + * This generates a buffer in the format Kerenelfilename::cmdline + * + * On success return 0. + * On failure return -EINVAL. + */ +int kexec_cmdline_prepend_img_name(char **outbuf, int kernel_fd, + const char *cmdline_ptr, + unsigned long cmdline_len) +{ + int ret = -EINVAL; + struct fd f = {}; + int size = 0; + char *buf = NULL; + char delimiter[] = "::"; + + if (!outbuf || !cmdline_ptr) + goto out; + + f = fdget(kernel_fd); + if (!f.file) + goto out; + + size = (f.file->f_path.dentry->d_name.len + cmdline_len - 1+ + ARRAY_SIZE(delimiter)) - 1; + + buf = kzalloc(size, GFP_KERNEL); + if (!buf) + goto out; + + memcpy(buf, f.file->f_path.dentry->d_name.name, + f.file->f_path.dentry->d_name.len); + memcpy(buf + f.file->f_path.dentry->d_name.len, + delimiter, ARRAY_SIZE(delimiter) - 1); + memcpy(buf + f.file->f_path.dentry->d_name.len + + ARRAY_SIZE(delimiter) - 1, + cmdline_ptr, cmdline_len - 1); + + *outbuf = buf; + ret = size; + + pr_debug("kexec cmdline buff: %s\n", buf); + +out: + if (f.file) + fdput(f); + + return ret; +} diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 2a5234eb4b28..a487491d55b9 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -126,6 +126,8 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, int ret = 0; void *ldata; loff_t size; + char *buff_to_measure = NULL; + int buff_to_measure_size = 0; ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, &size, INT_MAX, READING_KEXEC_IMAGE); @@ -183,8 +185,13 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, goto out; } - ima_buffer_check(image->cmdline_buf, cmdline_len - 1, - "kexec_cmdline"); + /* IMA measures the cmdline args passed to the next kernel*/ + buff_to_measure_size = kexec_cmdline_prepend_img_name(&buff_to_measure, + kernel_fd, image->cmdline_buf, image->cmdline_buf_len); + + ima_buffer_check(buff_to_measure, buff_to_measure_size, + "kexec_cmdline"); + } /* Call arch image load handlers */ @@ -200,6 +207,9 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, /* In case of error, free up all allocated memory in this function */ if (ret) kimage_file_post_load_cleanup(image); + + kfree(buff_to_measure); + return ret; } diff --git a/kernel/kexec_internal.h b/kernel/kexec_internal.h index 799a8a452187..4d34a8ef4637 100644 --- a/kernel/kexec_internal.h +++ b/kernel/kexec_internal.h @@ -11,6 +11,9 @@ int kimage_load_segment(struct kimage *image, struct kexec_segment *segment); void kimage_terminate(struct kimage *image); int kimage_is_destination_range(struct kimage *image, unsigned long start, unsigned long end); +int kexec_cmdline_prepend_img_name(char **outbuf, int kernel_fd, + const char *cmdline_ptr, + unsigned long cmdline_len); extern struct mutex kexec_mutex; -- 2.17.1