From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751693AbdFAPnf (ORCPT ); Thu, 1 Jun 2017 11:43:35 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:32937 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751669AbdFAPnd (ORCPT ); Thu, 1 Jun 2017 11:43:33 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Fabio Estevam" , "Marek Vasut" , "Herbert Xu" , "Tom Lendacky" , "David S. Miller" , "Shawn Guo" Date: Thu, 01 Jun 2017 16:40:55 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 087/101] crypto: hash - Simplify the ahash_finup implementation In-Reply-To: X-SA-Exim-Connect-IP: 82.70.136.246 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.89-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Marek Vasut commit d4a7a0fbe959e12bdd071b79b50ed34853a6db8f upstream. The ahash_def_finup() can make use of the request save/restore functions, thus make it so. This simplifies the code a little and unifies the code paths. Note that the same remark about free()ing the req->priv applies here, the req->priv can only be free()'d after the original request was restored. Finally, squash a bug in the invocation of completion in the ASYNC path. In both ahash_def_finup_done{1,2}, the function areq->base.complete(X, err); was called with X=areq->base.data . This is incorrect , as X=&areq->base is the correct value. By analysis of the data structures, we see the areq is of type 'struct ahash_request' , areq->base is of type 'struct crypto_async_request' and areq->base.completion is of type crypto_completion_t, which is defined in include/linux/crypto.h as: typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err); This is one lead that the X should be &areq->base . Next up, we can inspect other code which calls the completion callback to give us kind-of statistical idea of how this callback is used. We can try: $ git grep base\.complete\( drivers/crypto/ Finally, by inspecting ahash_request_set_callback() implementation defined in include/crypto/hash.h , we observe that the .data entry of 'struct crypto_async_request' is intended for arbitrary data, not for completion argument. Signed-off-by: Marek Vasut Cc: David S. Miller Cc: Fabio Estevam Cc: Herbert Xu Cc: Shawn Guo Cc: Tom Lendacky Signed-off-by: Herbert Xu Signed-off-by: Ben Hutchings --- crypto/ahash.c | 36 +++++++++--------------------------- 1 file changed, 9 insertions(+), 27 deletions(-) --- a/crypto/ahash.c +++ b/crypto/ahash.c @@ -350,19 +350,16 @@ static void ahash_def_finup_finish2(stru memcpy(priv->result, req->result, crypto_ahash_digestsize(crypto_ahash_reqtfm(req))); - kzfree(priv); + ahash_restore_req(req); } static void ahash_def_finup_done2(struct crypto_async_request *req, int err) { struct ahash_request *areq = req->data; - struct ahash_request_priv *priv = areq->priv; - crypto_completion_t complete = priv->complete; - void *data = priv->data; ahash_def_finup_finish2(areq, err); - complete(data, err); + areq->base.complete(&areq->base, err); } static int ahash_def_finup_finish1(struct ahash_request *req, int err) @@ -382,38 +379,23 @@ out: static void ahash_def_finup_done1(struct crypto_async_request *req, int err) { struct ahash_request *areq = req->data; - struct ahash_request_priv *priv = areq->priv; - crypto_completion_t complete = priv->complete; - void *data = priv->data; err = ahash_def_finup_finish1(areq, err); - complete(data, err); + areq->base.complete(&areq->base, err); } static int ahash_def_finup(struct ahash_request *req) { struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); - unsigned long alignmask = crypto_ahash_alignmask(tfm); - unsigned int ds = crypto_ahash_digestsize(tfm); - struct ahash_request_priv *priv; - - priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask), - (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? - GFP_KERNEL : GFP_ATOMIC); - if (!priv) - return -ENOMEM; - - priv->result = req->result; - priv->complete = req->base.complete; - priv->data = req->base.data; - - req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1); - req->base.complete = ahash_def_finup_done1; - req->base.data = req; - req->priv = priv; + int err; - return ahash_def_finup_finish1(req, tfm->update(req)); + err = ahash_save_req(req, ahash_def_finup_done1); + if (err) + return err; + + err = tfm->update(req); + return ahash_def_finup_finish1(req, err); } static int ahash_no_export(struct ahash_request *req, void *out)