From patchwork Wed Jul 11 20:36:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 10520447 X-Patchwork-Delegate: snitzer@redhat.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1533F603D7 for ; Wed, 11 Jul 2018 20:37:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E9609298BD for ; Wed, 11 Jul 2018 20:37:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E7820298D5; Wed, 11 Jul 2018 20:37:01 +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=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0EBDA29873 for ; Wed, 11 Jul 2018 20:37:00 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D6A14317C3EC; Wed, 11 Jul 2018 20:36:58 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A29EA3001A51; Wed, 11 Jul 2018 20:36:58 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 5C0A014B0F; Wed, 11 Jul 2018 20:36:58 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id w6BKaaQi014889 for ; Wed, 11 Jul 2018 16:36:36 -0400 Received: by smtp.corp.redhat.com (Postfix) id E4DA2600D1; Wed, 11 Jul 2018 20:36:36 +0000 (UTC) Delivered-To: dm-devel@redhat.com Received: from mx1.redhat.com (ext-mx03.extmail.prod.ext.phx2.redhat.com [10.5.110.27]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DD2C6600C2 for ; Wed, 11 Jul 2018 20:36:36 +0000 (UTC) Received: from mail-pf0-f196.google.com (mail-pf0-f196.google.com [209.85.192.196]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 82D4F80F7D for ; Wed, 11 Jul 2018 20:36:33 +0000 (UTC) Received: by mail-pf0-f196.google.com with SMTP id y8-v6so19133235pfm.10 for ; Wed, 11 Jul 2018 13:36:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Nat8iTKWvSD4ychV4rEE2eDXAa7pi2+ftb1Ei0FCzN0=; b=f6XSLcCZzFFkl9VmUGai36J/3eribp7AA+EMJa/1Z9AL8S9bJqwdX7dDFjTD9Ehhq3 DS7Sjyachtua2DsHkbXqCY73mGKRtPVwdas4hNmcHFf5NJHp0EGecjjvmxUWweDtk8kc WDtgCunxKER70BBOIo6B0tILqYoJubg20KZ30= 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=Nat8iTKWvSD4ychV4rEE2eDXAa7pi2+ftb1Ei0FCzN0=; b=JeOHq88FtXw5B7KDfAURgzITRJKLvwrIZne/MLAp6FqV6BTLqXxT7vSA9ea/4HWnHL 0gYe3x0VY155Rt26sU+x+ZNPS1jWluBILiGc0lqHiuPJwEXgg8wWZmsKUx8+JV7FXwBt f/9PuzFZf9tqpdBVw+H2O7eLCAwAwt1t2CNKzh8C2wY4UAqd8srusHiSe9H1kjxHLsDi kjUd3AWZNUPgBeRGf6w8ONLuJLSQ+huMHsF+iKI+SAj93329rGmxY0xaO5wrpUYZ2fke JPC7sWw9oooTjVUS1sGr0p3XpRkuK12QxTELwi1qvgbVt9nT+eMTNXQ0WzRHc8m2tVMy GI+A== X-Gm-Message-State: AOUpUlH4cK2Lb76l2o3h59mMSCgzjYCzBB9OitNUolH0t8eIF53dxgOc YF97c6atSAdPrZHv+R7frzJ0zGNBbDI= X-Google-Smtp-Source: AAOMgpdNPHZqs+Qc80qSqYJnRfArvvxMggIqsQbRZi4pfhdUB/UAp+gsXzKaqx5vXS6pS4uhXN09ww== X-Received: by 2002:a65:6645:: with SMTP id z5-v6mr126268pgv.71.1531341392429; Wed, 11 Jul 2018 13:36:32 -0700 (PDT) Received: from www.outflux.net (173-164-112-133-Oregon.hfc.comcastbusiness.net. [173.164.112.133]) by smtp.gmail.com with ESMTPSA id 84-v6sm34234208pfj.33.2018.07.11.13.36.27 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 11 Jul 2018 13:36:28 -0700 (PDT) From: Kees Cook To: Herbert Xu Date: Wed, 11 Jul 2018 13:36:17 -0700 Message-Id: <20180711203619.1020-13-keescook@chromium.org> In-Reply-To: <20180711203619.1020-1-keescook@chromium.org> References: <20180711203619.1020-1-keescook@chromium.org> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 11 Jul 2018 20:36:33 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 11 Jul 2018 20:36:33 +0000 (UTC) for IP:'209.85.192.196' DOMAIN:'mail-pf0-f196.google.com' HELO:'mail-pf0-f196.google.com' FROM:'keescook@chromium.org' RCPT:'' X-RedHat-Spam-Score: -0.112 (DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_PASS) 209.85.192.196 mail-pf0-f196.google.com 209.85.192.196 mail-pf0-f196.google.com X-Scanned-By: MIMEDefang 2.78 on 10.5.110.27 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-loop: dm-devel@redhat.com Cc: Giovanni Cabiddu , Kees Cook , Arnd Bergmann , Eric Biggers , Mike Snitzer , "Gustavo A. R. Silva" , qat-linux@intel.com, linux-kernel@vger.kernel.org, Masahiro Yamada , dm-devel@redhat.com, linux-crypto@vger.kernel.org, Lars Persson , Tim Chen , "David S. Miller" , Alasdair Kergon , Rabin Vincent Subject: [dm-devel] [PATCH v4 12/14] crypto: ahash: Remove VLA usage for AHASH_REQUEST_ON_STACK X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Wed, 11 Jul 2018 20:36:59 +0000 (UTC) X-Virus-Scanned: ClamAV using ClamSMTP In the quest to remove all stack VLA usage from the kernel[1], this caps the ahash request size similar to the other limits and adds a sanity check at registration. Unfortunately, these reqsizes can be very large. Looking at instrumented tcrypt output, the largest is for sha512: crypt: testing sha512 crypto_ahash_set_reqsize: 528 crypto_ahash_set_reqsize: 728 crypto_ahash_set_reqsize: 808 [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Signed-off-by: Kees Cook --- include/crypto/hash.h | 3 ++- include/crypto/internal/hash.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 4fcd0e2368cd..9290120536cd 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -66,10 +66,11 @@ struct ahash_request { #define AHASH_MAX_DIGESTSIZE 512 #define AHASH_MAX_STATESIZE 512 +#define AHASH_MAX_REQSIZE 808 #define AHASH_REQUEST_ON_STACK(name, ahash) \ char __##name##_desc[sizeof(struct ahash_request) + \ - crypto_ahash_reqsize(ahash)] CRYPTO_MINALIGN_ATTR; \ + AHASH_MAX_REQSIZE] CRYPTO_MINALIGN_ATTR; \ struct ahash_request *name = (void *)__##name##_desc /** diff --git a/include/crypto/internal/hash.h b/include/crypto/internal/hash.h index a0b0ad9d585e..d96ae5f52125 100644 --- a/include/crypto/internal/hash.h +++ b/include/crypto/internal/hash.h @@ -142,6 +142,7 @@ static inline struct ahash_alg *__crypto_ahash_alg(struct crypto_alg *alg) static inline void crypto_ahash_set_reqsize(struct crypto_ahash *tfm, unsigned int reqsize) { + BUG_ON(reqsize > AHASH_MAX_REQSIZE); tfm->reqsize = reqsize; }