From patchwork Tue Jan 29 00:34:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Edgecombe, Rick P" X-Patchwork-Id: 10785147 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4B7796C2 for ; Tue, 29 Jan 2019 00:39:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 37E562B4C4 for ; Tue, 29 Jan 2019 00:39:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2B9DB2B4D9; Tue, 29 Jan 2019 00:39:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AA5BA2B4C4 for ; Tue, 29 Jan 2019 00:39:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 07B528E0011; Mon, 28 Jan 2019 19:39:24 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id EF8A28E0010; Mon, 28 Jan 2019 19:39:23 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CF5AA8E0011; Mon, 28 Jan 2019 19:39:23 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-pl1-f197.google.com (mail-pl1-f197.google.com [209.85.214.197]) by kanga.kvack.org (Postfix) with ESMTP id 89B428E0010 for ; Mon, 28 Jan 2019 19:39:23 -0500 (EST) Received: by mail-pl1-f197.google.com with SMTP id v2so13025616plg.6 for ; Mon, 28 Jan 2019 16:39:23 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:from:to:cc :subject:date:message-id:in-reply-to:references; bh=1TyrV2qExacMWNjbbAQV/870MI2JQFH4ha6NlSEuZPU=; b=SJtQgoroL2gHm9oWiybKtX0n+4j2BGkRD4kOjov4RBDrytaTxLWfZ0jB2Qm9Zm/gVO gi9YfGdIRVIhUDw1ioN3W5Mqt8vFSSg4v/yvbpkJAM91S6Fv/dATlE3EdbRm5wP4ciDE a1gndRa12bvNyekUSItGQjsL5DQYjGWdXh7PrHqQoKRFn/00jnNKYRM5wXfRyEkTaAe4 dFROFqKoXOxLeFcx/DsduuPhoHKWzq6ipUT2WRiQp3vPhbu+A8oRzNxDJ/7O84X2ymK3 leyOywvRGjIeYlpfGxdmaxS2i9bx2Fa1hLWhmurLLmvL5dz3tyyt/LQg1KW7dY8i07Xk Yocg== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of rick.p.edgecombe@intel.com designates 192.55.52.120 as permitted sender) smtp.mailfrom=rick.p.edgecombe@intel.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com X-Gm-Message-State: AJcUukeImhszIJpdvfH9pg7U+yV+OnhBFOCYq6ShzqNrTwI53NLMhIzK JyQUGTBPna4R3gZ1IhHGmzFScmThFc/oxXIveBdWp0xVQxB9ZD2I0n5+64hd6uyGnRi2x00/1mv XGdXpDoFPxU1SnRBarA+XK6OMJlvEISwXKxgoExg+fVEYCPFA8S40MmAcFWLaP7eaew== X-Received: by 2002:a65:43c5:: with SMTP id n5mr22312206pgp.250.1548722363218; Mon, 28 Jan 2019 16:39:23 -0800 (PST) X-Google-Smtp-Source: ALg8bN5dM0MY7oBuKHcZBgcAxAEhe0HdRadyhEigPoYX71rwZu7lMtHwezvKxkhflIWZQac2imZ6 X-Received: by 2002:a65:43c5:: with SMTP id n5mr22311692pgp.250.1548722353162; Mon, 28 Jan 2019 16:39:13 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1548722353; cv=none; d=google.com; s=arc-20160816; b=hWWdjYR9u2gCnjhxtffgYXMcPEaldfJEI/SuyoTVJD/DTRxPLOpO25bDCpAQ4oIvT/ e3M7J0IyNIF8Z+K4LXnB52uhs2U6HTcgoiBB1eOrt6pOjWlh5VCxIGcGQ84pVsx75oH1 PPsfDT0bgfvQim1nXzt/s9k+EDvq6HTIhFvnveao7A0wKjAvGlwkjLFMeoeCco0rsS6T qE0LsOWT88qmuLlB5R5T7B45tJurV3Jt0bw6EHs+2qknjWMBLF5pOOh7ZNBBlyg4BhQn hmho119aTmePa9SPDfsXUMBfvr24/RTipKUUjeK24UPQw+7QSD4RsgCam2K/CxlSX0DH Zl4Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from; bh=1TyrV2qExacMWNjbbAQV/870MI2JQFH4ha6NlSEuZPU=; b=0ru26so2BDQCi245Xjjuic099V5hlhW7vKIrtu/YlkKzcGvp5IAlGiDxxz0KD/3ZFM HT4JhR0Kpvlmea8scDtbi1k4XDpDbIGlfVO8wn527o79bSjdgHdRxxCDwWqRfABHFo/A yOqSl8kjl3ZS7kdMhn5d9C+xMKXLhLfht5190Ks4K9zPwFr81SU3XTtCh+EmKkHNPisO 5KAwyDgBQA/1IzsiF/eGCW8IsOuoxpg1HG6NBSYi1ZhlZ1Di1hC5dkhL+mGHjEkkvcBh /GYferwhf3OQW89H7iWZCtXlfX8PQq4zPH9t2IwB577omJVzQlspZQ48/4JQ1p54JwLC GlOA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of rick.p.edgecombe@intel.com designates 192.55.52.120 as permitted sender) smtp.mailfrom=rick.p.edgecombe@intel.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: from mga04.intel.com (mga04.intel.com. [192.55.52.120]) by mx.google.com with ESMTPS id s17si4514712pgi.513.2019.01.28.16.39.12 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 28 Jan 2019 16:39:13 -0800 (PST) Received-SPF: pass (google.com: domain of rick.p.edgecombe@intel.com designates 192.55.52.120 as permitted sender) client-ip=192.55.52.120; Authentication-Results: mx.google.com; spf=pass (google.com: domain of rick.p.edgecombe@intel.com designates 192.55.52.120 as permitted sender) smtp.mailfrom=rick.p.edgecombe@intel.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 Jan 2019 16:39:11 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,535,1539673200"; d="scan'208";a="133921894" Received: from rpedgeco-desk5.jf.intel.com ([10.54.75.79]) by orsmga001.jf.intel.com with ESMTP; 28 Jan 2019 16:39:11 -0800 From: Rick Edgecombe To: Andy Lutomirski , Ingo Molnar Cc: linux-kernel@vger.kernel.org, x86@kernel.org, hpa@zytor.com, Thomas Gleixner , Borislav Petkov , Nadav Amit , Dave Hansen , Peter Zijlstra , linux_dti@icloud.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, akpm@linux-foundation.org, kernel-hardening@lists.openwall.com, linux-mm@kvack.org, will.deacon@arm.com, ard.biesheuvel@linaro.org, kristen@linux.intel.com, deneen.t.dock@intel.com, Nadav Amit , Kees Cook , Dave Hansen , Rick Edgecombe Subject: [PATCH v2 04/20] fork: provide a function for copying init_mm Date: Mon, 28 Jan 2019 16:34:06 -0800 Message-Id: <20190129003422.9328-5-rick.p.edgecombe@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190129003422.9328-1-rick.p.edgecombe@intel.com> References: <20190129003422.9328-1-rick.p.edgecombe@intel.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP From: Nadav Amit Provide a function for copying init_mm. This function will be later used for setting a temporary mm. Cc: Andy Lutomirski Cc: Kees Cook Cc: Dave Hansen Acked-by: Peter Zijlstra (Intel) Reviewed-by: Masami Hiramatsu Tested-by: Masami Hiramatsu Signed-off-by: Nadav Amit Signed-off-by: Rick Edgecombe --- include/linux/sched/task.h | 1 + kernel/fork.c | 24 ++++++++++++++++++------ 2 files changed, 19 insertions(+), 6 deletions(-) diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 44c6f15800ff..c5a00a7b3beb 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -76,6 +76,7 @@ extern void exit_itimers(struct signal_struct *); extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long); extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); struct task_struct *fork_idle(int); +struct mm_struct *copy_init_mm(void); extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); extern long kernel_wait4(pid_t, int __user *, int, struct rusage *); diff --git a/kernel/fork.c b/kernel/fork.c index b69248e6f0e0..d7b156c49f29 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1299,13 +1299,20 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm) complete_vfork_done(tsk); } -/* - * Allocate a new mm structure and copy contents from the - * mm structure of the passed in task structure. +/** + * dup_mm() - duplicates an existing mm structure + * @tsk: the task_struct with which the new mm will be associated. + * @oldmm: the mm to duplicate. + * + * Allocates a new mm structure and copy contents from the provided + * @oldmm structure. + * + * Return: the duplicated mm or NULL on failure. */ -static struct mm_struct *dup_mm(struct task_struct *tsk) +static struct mm_struct *dup_mm(struct task_struct *tsk, + struct mm_struct *oldmm) { - struct mm_struct *mm, *oldmm = current->mm; + struct mm_struct *mm; int err; mm = allocate_mm(); @@ -1372,7 +1379,7 @@ static int copy_mm(unsigned long clone_flags, struct task_struct *tsk) } retval = -ENOMEM; - mm = dup_mm(tsk); + mm = dup_mm(tsk, current->mm); if (!mm) goto fail_nomem; @@ -2187,6 +2194,11 @@ struct task_struct *fork_idle(int cpu) return task; } +struct mm_struct *copy_init_mm(void) +{ + return dup_mm(NULL, &init_mm); +} + /* * Ok, this is the main fork-routine. *