From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tadeusz Struk Subject: [PATCH] crypto: algif - Mark sgl end at the end of data Date: Fri, 28 Nov 2014 10:40:36 -0800 Message-ID: <20141128184036.11421.36028.stgit@tstruk-mobl1> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-crypto@vger.kernel.org, davem@davemloft.net To: herbert@gondor.apana.org.au Return-path: Received: from mga03.intel.com ([134.134.136.65]:19122 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751215AbaK1Snt (ORCPT ); Fri, 28 Nov 2014 13:43:49 -0500 Sender: linux-crypto-owner@vger.kernel.org List-ID: Hi, algif_skcipher sends 127 sgl buffers for encryption regardless of how many buffers acctually have data to process, where the few first with valid len and the rest with zero len. This is not very eficient and may cause problems when algs do something like this without checking the buff lenght: for_each_sg(sgl, sg, sg_nents, i) sg_virt(sg) This patch marks the last one with data as the last one to process. Signed-off-by: Tadeusz Struk --- crypto/algif_skcipher.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c index f80e652..46a0758 100644 --- a/crypto/algif_skcipher.c +++ b/crypto/algif_skcipher.c @@ -441,6 +441,8 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, char __user *from = iov->iov_base; while (seglen) { + int nents; + sgl = list_first_entry(&ctx->tsgl, struct skcipher_sg_list, list); sg = sgl->sg; @@ -468,6 +470,9 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, if (!used) goto free; + nents = sg_nents(ctx->rsgl.sg); + sg_mark_end(&sg[nents - 1]); + ablkcipher_request_set_crypt(&ctx->req, sg, ctx->rsgl.sg, used, ctx->iv); @@ -477,6 +482,7 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock, crypto_ablkcipher_encrypt(&ctx->req) : crypto_ablkcipher_decrypt(&ctx->req), &ctx->completion); + sg_unmark_end(&sg[nents - 1]); free: af_alg_free_sg(&ctx->rsgl);