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=-16.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 EA0A0C4360F for ; Tue, 26 Mar 2019 18:28:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BA20020879 for ; Tue, 26 Mar 2019 18:28:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Oz9kzY7d" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732691AbfCZS2V (ORCPT ); Tue, 26 Mar 2019 14:28:21 -0400 Received: from mail-qt1-f201.google.com ([209.85.160.201]:55895 "EHLO mail-qt1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732665AbfCZS2T (ORCPT ); Tue, 26 Mar 2019 14:28:19 -0400 Received: by mail-qt1-f201.google.com with SMTP id h51so14375447qte.22 for ; Tue, 26 Mar 2019 11:28:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=UWUYbOZniscPzPib57I8cPwH1j1zNPSziYufzU02lOY=; b=Oz9kzY7d3lv55fVkI6Kb0Gzd3zJwJVSAVP1ulUaw9XyfUgwUTFQ69SW1TpPJkSkz4I 8NUL2BguYiSmd8NFIwTgZKd7UB7lU8F2hm+SV82c1BpjE00Nve3eEAV5dCvYM6U0Adft 8cHrLisTQIpYkEfVr7pSsB7vKPAWYQArSJSuLNv7EWxW+QmxHN7LZdgApdkQI107/Ow2 GZ3GQday6ZqELcHEK3ZUIq2VgMJhr6I6/cma2bxfcIUaCW826/CfZVTmkThJ3vczr5og R+xZyn2RY8eloJabWhb+3U23suPmtoBLFDiFAW2oz2cFDyDctnrk/MCbULdQ+P4rFbUa 32UQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=UWUYbOZniscPzPib57I8cPwH1j1zNPSziYufzU02lOY=; b=o/Wd23G3vp4ZeuiQ+Jd4Xe4JFjB290GjMEjk6NkfZXu4PZau2DnT5qtwOs8n4c6eVR S1uForDS7vX0xl9F5vtDaoxrPUeceF7ys79WrVf7ioApGrhOmjpZiw4IYuktOMOvwZVM z7TS/dJRY7HTMm4IuFFSr2Eyg4fitsCHipdZtiHdvC7w1PDm51KLFFq7CqnUI514qWJK okdjFsb6mWBtzzm+975CdE0mLIbceosCdxjexBpHtQX8kIoqxwXvR9X1WcqDs6VCgZtQ BNVJ3kMJQxM9opAYm5Bj2AdjrtiUcigIne23OD2UZQ+RYvqzjZM2VdAcQ+o3RDLcrj5C HpIQ== X-Gm-Message-State: APjAAAVP46UCbfFi8ynL78unKxY0RA6A5J6UW0GXjygkI3fcuwgmsGlN OuEjYQbcZBYqXvORRdVr9NG+dR6yFSX5VenK3HH2qQ== X-Google-Smtp-Source: APXvYqy8T5iMSU8bRAJDeiOYdZ+vf7wI+oEKQds8Wx9UYe7VIOiL7DRxsniEJLG6jiM0ADBnIZ62Ujuch6uEFVoBA5UeiQ== X-Received: by 2002:ac8:1091:: with SMTP id a17mr25977158qtj.135.1553624898035; Tue, 26 Mar 2019 11:28:18 -0700 (PDT) Date: Tue, 26 Mar 2019 11:27:25 -0700 In-Reply-To: <20190326182742.16950-1-matthewgarrett@google.com> Message-Id: <20190326182742.16950-10-matthewgarrett@google.com> Mime-Version: 1.0 References: <20190326182742.16950-1-matthewgarrett@google.com> X-Mailer: git-send-email 2.21.0.392.gf8f6787159e-goog Subject: [PATCH V31 09/25] uswsusp: Disable when the kernel is locked down From: Matthew Garrett To: jmorris@namei.org Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-api@vger.kernel.org, luto@kernel.org, Matthew Garrett , Matthew Garrett , linux-pm@vger.kernel.org, pavel@ucw.cz, rjw@rjwysocki.net Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Matthew Garrett uswsusp allows a user process to dump and then restore kernel state, which makes it possible to modify the running kernel. Disable this if the kernel is locked down. Signed-off-by: David Howells Signed-off-by: Matthew Garrett cc: linux-pm@vger.kernel.org Cc: pavel@ucw.cz Cc: rjw@rjwysocki.net --- kernel/power/user.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/power/user.c b/kernel/power/user.c index 2d8b60a3c86b..99e13fd13237 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -52,6 +52,9 @@ static int snapshot_open(struct inode *inode, struct file *filp) if (!hibernation_available()) return -EPERM; + if (kernel_is_locked_down("/dev/snapshot", LOCKDOWN_INTEGRITY)) + return -EPERM; + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { -- 2.21.0.392.gf8f6787159e-goog