From patchwork Wed Jun 29 10:29:15 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herbert Xu X-Patchwork-Id: 9204767 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 E0A1E6075F for ; Wed, 29 Jun 2016 10:29:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D21BE28569 for ; Wed, 29 Jun 2016 10:29:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C678D2864C; Wed, 29 Jun 2016 10:29:21 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham 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 CFD6B28624 for ; Wed, 29 Jun 2016 10:29:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751290AbcF2K3T (ORCPT ); Wed, 29 Jun 2016 06:29:19 -0400 Received: from helcar.hengli.com.au ([209.40.204.226]:56749 "EHLO helcar.hengli.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751308AbcF2K3S (ORCPT ); Wed, 29 Jun 2016 06:29:18 -0400 Received: from gondolin.me.apana.org.au ([192.168.0.6]) by norbury.hengli.com.au with esmtp (Exim 4.80 #3 (Debian)) id 1bICk7-0005tz-LE; Wed, 29 Jun 2016 20:29:15 +1000 Received: from herbert by gondolin.me.apana.org.au with local (Exim 4.80) (envelope-from ) id 1bICk7-00072n-17; Wed, 29 Jun 2016 18:29:15 +0800 Subject: [v3 PATCH 3/8] lib/mpi: Do not do sg_virt References: <20160629102649.GA26987@gondor.apana.org.au> To: Andrzej Zaborowski , Tadeusz Struk , Linux Crypto Mailing List , Tudor Ambarus , Stephan Mueller , Mat Martineau , Denis Kenzior , Salvatore Benedetto Message-Id: From: Herbert Xu Date: Wed, 29 Jun 2016 18:29:15 +0800 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 Currently the mpi SG helpers use sg_virt which is completely broken. It happens to work with normal kernel memory but will fail with anything that is not linearly mapped. This patch fixes this by using the SG iterator helpers. Signed-off-by: Herbert Xu --- lib/mpi/mpicoder.c | 86 ++++++++++++++++++++++++++++++----------------------- 1 file changed, 50 insertions(+), 36 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c index 7150e5c..c6272ae 100644 --- a/lib/mpi/mpicoder.c +++ b/lib/mpi/mpicoder.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include "mpi-internal.h" @@ -255,7 +256,9 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned nbytes, #error please implement for this limb size. #endif unsigned int n = mpi_get_size(a); + struct sg_mapping_iter miter; int i, x, buf_len; + int nents; if (sign) *sign = a->sign; @@ -263,23 +266,27 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned nbytes, if (nbytes < n) return -EOVERFLOW; - buf_len = sgl->length; - p2 = sg_virt(sgl); + nents = sg_nents_for_len(sgl, nbytes); + if (nents < 0) + return -EINVAL; - while (nbytes > n) { - if (!buf_len) { - sgl = sg_next(sgl); - if (!sgl) - return -EINVAL; - buf_len = sgl->length; - p2 = sg_virt(sgl); - } + sg_miter_start(&miter, sgl, nents, SG_MITER_ATOMIC | SG_MITER_TO_SG); + sg_miter_next(&miter); + buf_len = miter.length; + p2 = miter.addr; + while (nbytes > n) { i = min_t(unsigned, nbytes - n, buf_len); memset(p2, 0, i); p2 += i; - buf_len -= i; nbytes -= i; + + buf_len -= i; + if (!buf_len) { + sg_miter_next(&miter); + buf_len = miter.length; + p2 = miter.addr; + } } for (i = a->nlimbs - 1; i >= 0; i--) { @@ -293,17 +300,16 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned nbytes, p = (u8 *)&alimb; for (x = 0; x < sizeof(alimb); x++) { - if (!buf_len) { - sgl = sg_next(sgl); - if (!sgl) - return -EINVAL; - buf_len = sgl->length; - p2 = sg_virt(sgl); - } *p2++ = *p++; - buf_len--; + if (!--buf_len) { + sg_miter_next(&miter); + buf_len = miter.length; + p2 = miter.addr; + } } } + + sg_miter_stop(&miter); return 0; } EXPORT_SYMBOL_GPL(mpi_write_to_sgl); @@ -323,19 +329,23 @@ EXPORT_SYMBOL_GPL(mpi_write_to_sgl); */ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes) { - struct scatterlist *sg; - int x, i, j, z, lzeros, ents; + struct sg_mapping_iter miter; unsigned int nbits, nlimbs; + int x, j, z, lzeros, ents; + unsigned int len; + const u8 *buff; mpi_limb_t a; MPI val = NULL; - lzeros = 0; - ents = sg_nents(sgl); + ents = sg_nents_for_len(sgl, nbytes); + if (ents < 0) + return NULL; - for_each_sg(sgl, sg, ents, i) { - const u8 *buff = sg_virt(sg); - int len = sg->length; + sg_miter_start(&miter, sgl, ents, SG_MITER_ATOMIC | SG_MITER_FROM_SG); + lzeros = 0; + len = 0; + while (nbytes > 0) { while (len && !*buff) { lzeros++; len--; @@ -345,12 +355,14 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes) if (len && *buff) break; - ents--; + sg_miter_next(&miter); + buff = miter.addr; + len = miter.length; + nbytes -= lzeros; lzeros = 0; } - sgl = sg; nbytes -= lzeros; nbits = nbytes * 8; if (nbits > MAX_EXTERN_MPI_BITS) { @@ -359,8 +371,7 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes) } if (nbytes > 0) - nbits -= count_leading_zeros(*(u8 *)(sg_virt(sgl) + lzeros)) - - (BITS_PER_LONG - 8); + nbits -= count_leading_zeros(*buff) - (BITS_PER_LONG - 8); nlimbs = DIV_ROUND_UP(nbytes, BYTES_PER_MPI_LIMB); val = mpi_alloc(nlimbs); @@ -379,21 +390,24 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes) z = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB; z %= BYTES_PER_MPI_LIMB; - for_each_sg(sgl, sg, ents, i) { - const u8 *buffer = sg_virt(sg) + lzeros; - int len = sg->length - lzeros; - + for (;;) { for (x = 0; x < len; x++) { a <<= 8; - a |= *buffer++; + a |= *buff++; if (((z + x + 1) % BYTES_PER_MPI_LIMB) == 0) { val->d[j--] = a; a = 0; } } z += x; - lzeros = 0; + + if (!sg_miter_next(&miter)) + break; + + buff = miter.addr; + len = miter.length; } + return val; } EXPORT_SYMBOL_GPL(mpi_read_raw_from_sgl);