From: Herbert Xu Subject: Re: [PATCH v4 3/3] crypto: Add Allwinner Security System crypto accelerator Date: Thu, 24 Jul 2014 14:00:54 +0800 Message-ID: <20140724060054.GA6545@gondor.apana.org.au> References: <1405169953-13695-1-git-send-email-clabbe.montjoie@gmail.com> <1405169953-13695-4-git-send-email-clabbe.montjoie@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, rdunlap@infradead.org, maxime.ripard@free-electrons.com, linux@arm.linux.org.uk, davem@davemloft.net, grant.likely@linaro.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org To: LABBE Corentin Return-path: Received: from helcar.apana.org.au ([209.40.204.226]:42355 "EHLO helcar.apana.org.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750904AbaGXGBx (ORCPT ); Thu, 24 Jul 2014 02:01:53 -0400 Content-Disposition: inline In-Reply-To: <1405169953-13695-4-git-send-email-clabbe.montjoie@gmail.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Sat, Jul 12, 2014 at 02:59:13PM +0200, LABBE Corentin wrote: > > +/* sunxi_hash_init: initialize request context > + * Activate the SS, and configure it for MD5 or SHA1 > + */ > +int sunxi_hash_init(struct ahash_request *areq) > +{ > + const char *hash_type; > + struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); > + struct sunxi_req_ctx *op = crypto_ahash_ctx(tfm); > + > + mutex_lock(&ss->lock); > + > + hash_type = crypto_tfm_alg_name(areq->base.tfm); > + > + op->byte_count = 0; > + op->nbwait = 0; > + op->waitbuf = 0; > + > + /* Enable and configure SS for MD5 or SHA1 */ > + if (strcmp(hash_type, "sha1") == 0) > + op->mode = SS_OP_SHA1; > + else > + op->mode = SS_OP_MD5; > + > + writel(op->mode | SS_ENABLED, ss->base + SS_CTL); > + return 0; The hash driver is completely broken. You are modifying tfm ctx data which is shared by all users of a single tfm. So if two users conduct hashes in parallel they will step all over each other. Worse, the unpaired mutex_lock will quickly lead to dead locks. You cannot assume that final will be called. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt