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Shutemov" X-Patchwork-Id: 11068199 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 26AFB746 for ; Wed, 31 Jul 2019 15:14:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1258D20246 for ; Wed, 31 Jul 2019 15:14:42 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 06B66205F6; Wed, 31 Jul 2019 15:14:42 +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,DKIM_SIGNED, DKIM_VALID,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 6BBC820246 for ; Wed, 31 Jul 2019 15:14:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CBDDA8E002A; Wed, 31 Jul 2019 11:13:59 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id BD32F8E0030; Wed, 31 Jul 2019 11:13:59 -0400 (EDT) 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 9FC268E002A; Wed, 31 Jul 2019 11:13:59 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id 4238E8E0030 for ; Wed, 31 Jul 2019 11:13:59 -0400 (EDT) Received: by mail-ed1-f70.google.com with SMTP id i44so42652135eda.3 for ; Wed, 31 Jul 2019 08:13:59 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=bD/5ZInA5DBfNF/OoolUD2uLCIaOC1DGsUwSCxp+njs=; b=VIzL4VAPT63JmqODvU+FF2JFcKiMBCtmRAmZFGS2xI5pAdiaxUNLXAnxhv8tvgAWiC 1i0nIiBDGIP9cmj9tqSwkz9cq8GEgpuI/Mhl4xXEiLk0PDFxVEZdQnxGQqRyRp0Ej+tA naml+my21KzhEIiIvmFO/st1YgA31LbV1Me8Pi2O6xK16JAnquOuQM97cpqnbz89RHel P3aduIjAjpHySwDw+IQInqslxOsI+zrTyjjApoCWBB82WcTToZmTpzrGL5pl3d62aSgF 4cLLBvU7u2QlZyIrp6FdTeSODZpf3GgB8pvRONgz5UxoS/93bo4+zb5gnfT9XKJDZP0g ntcg== X-Gm-Message-State: APjAAAUS04WwyCmBsCnZNYjDDy4TLJVGXeZ1fHIeYVJJJyZp5yMaIiRS GTooqkvt55MqBytJuVKYjGF8F+2LiLTBEGlObSc3Tg8Ah9Ej2ZbRbvRY2lUi+inkpZvqK6ANsGF D1QJeBu8iRVVRgE25VZ9F2OWQgTEYLitHoiq+NPb2hF/0F82Gg+XtAdwHgKrSWBs= X-Received: by 2002:a50:e718:: with SMTP id a24mr106273300edn.91.1564586038834; Wed, 31 Jul 2019 08:13:58 -0700 (PDT) X-Received: by 2002:a50:e718:: with SMTP id a24mr106273185edn.91.1564586037618; Wed, 31 Jul 2019 08:13:57 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1564586037; cv=none; d=google.com; s=arc-20160816; b=NmC8724Zj/0RlCcCjVwJz0WHV2EY4X2DUznZDkQzjC84ZMk37P2cEo6x0ICZwAl9YA cMos8UrEqm+/UydvU1yU0rvg+6ogIlJoL6QhJ4+EU6wqlR8TQT73/cAlh9bFarbQlPe9 EX2ZvBsBOekQpxcHYbEJ4fjWAbmMkfbNJFJDjBS+SSXFsbpbFFWN1C+osQfTzpndrJ4U JvRV1xmmwF7CuZdxoMgexUfpB5flluKGdp0RaLSCnC5NLGGo5l6NIgJPFoe2rhuroTBG jrodVms/0T8YWSjZ1rYnvWoLeoo/1yhn/Q4AjzMiGfES0eexVUM2Hj73phWe9jSAPauY XaZw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:dkim-signature; bh=bD/5ZInA5DBfNF/OoolUD2uLCIaOC1DGsUwSCxp+njs=; b=Uzt0iMYvhfeAiXBipuOSIpzBUA8PBj/aI7+qUmLqnEHxs93X7YFULz8NgH+1mnzc5R 8VPa3FtxeywTbgoUPLoKamQb6zf+dRjwgzF+uBaBCub0XQSpZgyHBIETSjYbC9pd8EYe T7WEHtJqmYuvgoKtU1eldOHSuvVUAX48kqk7/PX7QidYjeF667Hj9460wgzqf6ub0HoH 57goKO2OR85rMU8AdLI49NLs3tlAb54Ye6TFW+ot4HZ5L9OKPa+g3ctPFPE89osJvSkS qn4DkNUrUFofaU3OQZbNTZquTvBwtNY51A9ZF4eXST4B60bHHJNvM20SRr6Tcd1CRGck T37w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@shutemov-name.20150623.gappssmtp.com header.s=20150623 header.b=nvqdVZ7h; spf=neutral (google.com: 209.85.220.65 is neither permitted nor denied by best guess record for domain of kirill@shutemov.name) smtp.mailfrom=kirill@shutemov.name Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. 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Shutemov" X-Google-Original-From: "Kirill A. Shutemov" Received: by box.localdomain (Postfix, from userid 1000) id C65041044A6; Wed, 31 Jul 2019 18:08:16 +0300 (+03) To: Andrew Morton , x86@kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Borislav Petkov , Peter Zijlstra , Andy Lutomirski , David Howells Cc: Kees Cook , Dave Hansen , Kai Huang , Jacob Pan , Alison Schofield , linux-mm@kvack.org, kvm@vger.kernel.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A . Shutemov" Subject: [PATCHv2 31/59] keys/mktme: Set up a percpu_ref_count for MKTME keys Date: Wed, 31 Jul 2019 18:07:45 +0300 Message-Id: <20190731150813.26289-32-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190731150813.26289-1-kirill.shutemov@linux.intel.com> References: <20190731150813.26289-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 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: Alison Schofield The MKTME key service needs to keep usage counts on the encryption keys in order to know when it is safe to free a key for reuse. percpu_ref_count applies well here because the key service will take the initial reference and typically hold that reference while the intermediary references are get/put. The intermediaries in this case will be encrypted VMA's, Align the percpu_ref_init and percpu_ref_kill with the key service instantiate and destroy methods respectively. Signed-off-by: Alison Schofield Signed-off-by: Kirill A. Shutemov --- security/keys/mktme_keys.c | 39 +++++++++++++++++++++++++++++++++++++- 1 file changed, 38 insertions(+), 1 deletion(-) diff --git a/security/keys/mktme_keys.c b/security/keys/mktme_keys.c index 3c641f3ee794..18cb57be5193 100644 --- a/security/keys/mktme_keys.c +++ b/security/keys/mktme_keys.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -71,6 +72,26 @@ int mktme_keyid_from_key(struct key *key) return 0; } +struct percpu_ref *encrypt_count; +void mktme_percpu_ref_release(struct percpu_ref *ref) +{ + unsigned long flags; + int keyid; + + for (keyid = 1; keyid <= mktme_nr_keyids(); keyid++) { + if (&encrypt_count[keyid] == ref) + break; + } + if (&encrypt_count[keyid] != ref) { + pr_debug("%s: invalid ref counter\n", __func__); + return; + } + percpu_ref_exit(ref); + spin_lock_irqsave(&mktme_lock, flags); + mktme_release_keyid(keyid); + spin_unlock_irqrestore(&mktme_lock, flags); +} + enum mktme_opt_id { OPT_ERROR, OPT_TYPE, @@ -199,8 +220,10 @@ static void mktme_destroy_key(struct key *key) unsigned long flags; spin_lock_irqsave(&mktme_lock, flags); - mktme_release_keyid(keyid); + mktme_map[keyid].key = NULL; + mktme_map[keyid].state = KEYID_REF_KILLED; spin_unlock_irqrestore(&mktme_lock, flags); + percpu_ref_kill(&encrypt_count[keyid]); } /* Key Service Method to create a new key. Payload is preparsed. */ @@ -216,9 +239,15 @@ int mktme_instantiate_key(struct key *key, struct key_preparsed_payload *prep) if (!keyid) return -ENOKEY; + if (percpu_ref_init(&encrypt_count[keyid], mktme_percpu_ref_release, + 0, GFP_KERNEL)) + goto err_out; + if (!mktme_program_keyid(keyid, *payload)) return MKTME_PROG_SUCCESS; + percpu_ref_exit(&encrypt_count[keyid]); +err_out: spin_lock_irqsave(&mktme_lock, flags); mktme_release_keyid(keyid); spin_unlock_irqrestore(&mktme_lock, flags); @@ -405,10 +434,18 @@ static int __init init_mktme(void) /* Initialize first programming targets */ mktme_update_pconfig_targets(); + /* Reference counters to protect in use KeyIDs */ + encrypt_count = kvcalloc(mktme_nr_keyids() + 1, sizeof(encrypt_count[0]), + GFP_KERNEL); + if (!encrypt_count) + goto free_targets; + ret = register_key_type(&key_type_mktme); if (!ret) return ret; /* SUCCESS */ + kvfree(encrypt_count); +free_targets: free_cpumask_var(mktme_leadcpus); bitmap_free(mktme_target_map); free_cache: