From patchwork Tue Jul 24 16:49:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 10542621 X-Patchwork-Delegate: kvalo@adurom.com 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 1B56C112E for ; Tue, 24 Jul 2018 16:52:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BCFA3291EA for ; Tue, 24 Jul 2018 16:52:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B8B2429101; Tue, 24 Jul 2018 16:52:04 +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 5829C29181 for ; Tue, 24 Jul 2018 16:52:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388579AbeGXR5M (ORCPT ); Tue, 24 Jul 2018 13:57:12 -0400 Received: from mail-pl0-f67.google.com ([209.85.160.67]:43092 "EHLO mail-pl0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388578AbeGXR5L (ORCPT ); Tue, 24 Jul 2018 13:57:11 -0400 Received: by mail-pl0-f67.google.com with SMTP id x6-v6so333469plv.10 for ; Tue, 24 Jul 2018 09:49:51 -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=xi1UiijgPtH3bEbgxLJTLT+H3zXPa7fDlbmxyBVC5QY=; b=dyArO5HPDOmgxu1KqX1PLyjELlLB/4D/84YPYAORv5WvH1EukArfqKSZklwmUMMB7a /TGpsRkqAMjiQVw/mB48Ccn1vguQr0t20yF9CE+lGYxame7S7lxWefDK14kQapdlhLEk 203wUEPeCBMmH4vWUkmIeSP0Tbz3jZdvFjhbE= 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=xi1UiijgPtH3bEbgxLJTLT+H3zXPa7fDlbmxyBVC5QY=; b=rzj28u0TaRCjWycH96sJaVjeKbIarzRrvMqMRJDMXsnxdUp2SGBDJVoYZUWsoAJlqt B85qELvPGf2QHpF4nLR0YqokHIB2IJPr0upvm0ib+MgsQ884aB0iz7pzDfN69X5xz6EN 5kEYW5ZmSpjTm5fCvbm9Ux9m2a0UKNM72NOjD4UGbHAVjyRL6NL5/m1HYjT+n9EA7iQP O34AYvlhPnvWixN8YFt54zXaervbsg65Q2gBqh96ZPMh1CG8Edsnhe/UNFvueZjYndOL 7aS8nPdD5XP52aHovdtHc1WO+zY1filpI7F4vSCn2ddBxSDYHI2KjNQ/pZJ8/1LL7cfZ 9OBw== X-Gm-Message-State: AOUpUlGHt7Pg2F/ahJJWmvhp+P1f+ntVnHpZnqAmW0qDNd+NhmCb65Mj rxnTe4XbPuHQ4TK5UTd3I2Ax/w== X-Google-Smtp-Source: AAOMgpeVOEL3rwh7h++k7IUoH+FXXTX0DIe/o1QEmZSs2q6LYLTUBCJLP1OSBUBvuU8XEGR4LWmKqA== X-Received: by 2002:a17:902:b112:: with SMTP id q18-v6mr17394185plr.284.1532450990853; Tue, 24 Jul 2018 09:49:50 -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 e2-v6sm13671874pgo.92.2018.07.24.09.49.45 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 24 Jul 2018 09:49:47 -0700 (PDT) From: Kees Cook To: Herbert Xu Cc: Kees Cook , Arnd Bergmann , Eric Biggers , "Gustavo A. R. Silva" , Alasdair Kergon , Rabin Vincent , Tim Chen , "Rafael J. Wysocki" , Pavel Machek , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Philipp Reisner , Lars Ellenberg , Jens Axboe , Giovanni Cabiddu , Mike Snitzer , Paul Mackerras , Greg Kroah-Hartman , David Howells , Johannes Berg , Tudor-Dan Ambarus , Jia-Ju Bai , Andrew Morton , Geert Uytterhoeven , Josh Poimboeuf , David Woodhouse , Will Deacon , dm-devel@redhat.com, linux-pm@vger.kernel.org, linux-crypto@vger.kernel.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, qat-linux@intel.com, linux-ppp@vger.kernel.org, netdev@vger.kernel.org, devel@driverdev.osuosl.org, linux-afs@lists.infradead.org, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v6 08/18] crypto: skcipher: Remove VLA usage for SKCIPHER_REQUEST_ON_STACK Date: Tue, 24 Jul 2018 09:49:26 -0700 Message-Id: <20180724164936.37477-9-keescook@chromium.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180724164936.37477-1-keescook@chromium.org> References: <20180724164936.37477-1-keescook@chromium.org> Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In the quest to remove all stack VLA usage from the kernel[1], this caps the skcipher request size similar to other limits and adds a sanity check at registration. Looking at instrumented tcrypt output, the largest is for lrw: crypt: testing lrw(aes) crypto_skcipher_set_reqsize: 8 crypto_skcipher_set_reqsize: 88 crypto_skcipher_set_reqsize: 472 [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Signed-off-by: Kees Cook --- include/crypto/internal/skcipher.h | 1 + include/crypto/skcipher.h | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/crypto/internal/skcipher.h b/include/crypto/internal/skcipher.h index e42f7063f245..5035482cbe68 100644 --- a/include/crypto/internal/skcipher.h +++ b/include/crypto/internal/skcipher.h @@ -130,6 +130,7 @@ static inline struct crypto_skcipher *crypto_spawn_skcipher( static inline void crypto_skcipher_set_reqsize( struct crypto_skcipher *skcipher, unsigned int reqsize) { + BUG_ON(reqsize > SKCIPHER_MAX_REQSIZE); skcipher->reqsize = reqsize; } diff --git a/include/crypto/skcipher.h b/include/crypto/skcipher.h index 2f327f090c3e..c48e194438cf 100644 --- a/include/crypto/skcipher.h +++ b/include/crypto/skcipher.h @@ -139,9 +139,11 @@ struct skcipher_alg { struct crypto_alg base; }; +#define SKCIPHER_MAX_REQSIZE 472 + #define SKCIPHER_REQUEST_ON_STACK(name, tfm) \ char __##name##_desc[sizeof(struct skcipher_request) + \ - crypto_skcipher_reqsize(tfm)] CRYPTO_MINALIGN_ATTR; \ + SKCIPHER_MAX_REQSIZE] CRYPTO_MINALIGN_ATTR; \ struct skcipher_request *name = (void *)__##name##_desc /**