From patchwork Fri Jun 29 00:28:37 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 10495465 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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 59BC1602B3 for ; Fri, 29 Jun 2018 00:30:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 47C7A29E3F for ; Fri, 29 Jun 2018 00:30:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3BAEE29E7A; Fri, 29 Jun 2018 00:30:54 +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=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E657229E3F for ; Fri, 29 Jun 2018 00:30:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934575AbeF2A2v (ORCPT ); Thu, 28 Jun 2018 20:28:51 -0400 Received: from mail-pf0-f195.google.com ([209.85.192.195]:41481 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933005AbeF2A2u (ORCPT ); Thu, 28 Jun 2018 20:28:50 -0400 Received: by mail-pf0-f195.google.com with SMTP id a11-v6so3355274pff.8 for ; Thu, 28 Jun 2018 17:28:49 -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=1FLR47NZKUpOfOHNU+o+a5PLOZJlTKUqZN/VmdUBfgs=; b=MkAQPvaqxyGks++34Jvs5iRnMVknuigdmi6qgS6qZsSecxqqSzmSqSDewi/i2++CPW Z9atPQ6gW6YyDeU1F/EsAcR3Vw2iE+0Mu+x55S3msanXqW9mc07xoEcmCRy2TTB9mSjf HbKmzYeEUOfrIxpnZJMmceEIkvjUwZOX1OjMk= 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=1FLR47NZKUpOfOHNU+o+a5PLOZJlTKUqZN/VmdUBfgs=; b=IAak1CldvNU5VBXtDaUFgTgxLDWyKMiVzhXNbBJYCKP+laN/sY9owqOw20ukDwMsCJ k0h9rARUQ6ER5FLEzVVYsU3s8nmgn9ZUzhKHxrqtutJZxsLfsqtTrCWc9b8njJTszZBn 3wchwZHQpmqeg+5tQaAsbmoDjBpicdlRYPH8KsUNNHwI0Tzz6vr/7/26oq4bSSQEGonQ wDxnXdZneYsChmY3I5Vmm1m7AShErU9Gs+nHWEieiNRhlnKkqTmHWg3YCtsZXH0sR3gX WN1bccbZw7imyoS62Dzyq3/b97MU4LT/jfLluD3Ph5n4jKQsOfeQxUNuYfD/jVDxsx+Q s5kQ== X-Gm-Message-State: APt69E2h8nh4FdzA+1lSLII6L3V16q0qFX///j5ZcLDsyRAWFVQr7YPk DCP1h5YZVGDKURSVHdUjUdlzLA== X-Google-Smtp-Source: AAOMgpfqKh/DeqajN1MA0ClR8XN59h8H9cvpsI5D+gyzFQgoB4+aaUKl1quIavGDKI7keB2pKKcciA== X-Received: by 2002:a65:4304:: with SMTP id j4-v6mr3102693pgq.109.1530232129660; Thu, 28 Jun 2018 17:28:49 -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 74-v6sm16771187pfj.127.2018.06.28.17.28.47 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 28 Jun 2018 17:28:48 -0700 (PDT) From: Kees Cook To: Herbert Xu Cc: Kees Cook , "Gustavo A. R. Silva" , Arnd Bergmann , Eric Biggers , Alasdair Kergon , Giovanni Cabiddu , Lars Persson , Mike Snitzer , Rabin Vincent , Tim Chen , "David S. Miller" , linux-crypto@vger.kernel.org, qat-linux@intel.com, dm-devel@redhat.com, linux-kernel@vger.kernel.org Subject: [PATCH v3 3/9] crypto: shash: Remove VLA usage Date: Thu, 28 Jun 2018 17:28:37 -0700 Message-Id: <20180629002843.31095-4-keescook@chromium.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180629002843.31095-1-keescook@chromium.org> References: <20180629002843.31095-1-keescook@chromium.org> Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In the quest to remove all stack VLA usage from the kernel[1], this removes the VLAs in SHASH_DESC_ON_STACK (via crypto_shash_descsize()) by using the maximum allowable size (which is now more clearly captured in a macro). Similar limits are turned into macros as well. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Signed-off-by: Kees Cook --- crypto/shash.c | 6 +++--- include/crypto/hash.h | 6 +++++- 2 files changed, 8 insertions(+), 4 deletions(-) diff --git a/crypto/shash.c b/crypto/shash.c index 5d732c6bb4b2..ab6902c6dae7 100644 --- a/crypto/shash.c +++ b/crypto/shash.c @@ -458,9 +458,9 @@ static int shash_prepare_alg(struct shash_alg *alg) { struct crypto_alg *base = &alg->base; - if (alg->digestsize > PAGE_SIZE / 8 || - alg->descsize > PAGE_SIZE / 8 || - alg->statesize > PAGE_SIZE / 8) + if (alg->digestsize > SHASH_MAX_DIGESTSIZE || + alg->descsize > SHASH_MAX_DESCSIZE || + alg->statesize > SHASH_MAX_STATESIZE) return -EINVAL; base->cra_type = &crypto_shash_type; diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 76e432cab75d..804e87a9510e 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -151,9 +151,13 @@ struct shash_desc { void *__ctx[] CRYPTO_MINALIGN_ATTR; }; +#define SHASH_MAX_DIGESTSIZE 512 +#define SHASH_MAX_DESCSIZE 512 +#define SHASH_MAX_STATESIZE 512 + #define SHASH_DESC_ON_STACK(shash, ctx) \ char __##shash##_desc[sizeof(struct shash_desc) + \ - crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \ + SHASH_MAX_DESCSIZE] CRYPTO_MINALIGN_ATTR; \ struct shash_desc *shash = (struct shash_desc *)__##shash##_desc /**