From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD606C10F14 for ; Thu, 10 Oct 2019 09:02:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 87EFB2067B for ; Thu, 10 Oct 2019 09:02:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570698176; bh=rdcIxeP4m44G4RKG8Wgygl8lX/dUoxoPTmdfFUaKgR8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XxYh8Ro7AnAzpyOEhAlocRFPWqOiMeClB3vYApphgxCBTLM06cNoEXzjqI3+kIm0G ZUDZcLsJMzPISelT3Kxehl41Wz+/qY4rJyNIcPB/kwBcQQQb901Z1qwWd5qPWUkURA Nv7/TUQg8lI7qPxZ2apGhJf/MIlEaZr2ToLrfQQo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388675AbfJJJCz (ORCPT ); Thu, 10 Oct 2019 05:02:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:42556 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733279AbfJJIjO (ORCPT ); Thu, 10 Oct 2019 04:39:14 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6817121D6C; Thu, 10 Oct 2019 08:39:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570696753; bh=rdcIxeP4m44G4RKG8Wgygl8lX/dUoxoPTmdfFUaKgR8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MR53nh5fRv5BAFO6rre0kbiF9aUrAWMbXxybj5FpYSv24a6gjnEuwS3wqn1sv290q 8Wck1Aa1yOUqnoHEqcxb8ukDMC9LVG+vRaWmpL590OGa7xOpRLlA3BMoxexu6ZkfkS 84/7mSlTzwjvQWVStkzVzyaH8iQefP63v08Jmor4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , Herbert Xu Subject: [PATCH 5.3 041/148] crypto: skcipher - Unmap pages after an external error Date: Thu, 10 Oct 2019 10:35:02 +0200 Message-Id: <20191010083613.631776460@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191010083609.660878383@linuxfoundation.org> References: <20191010083609.660878383@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Herbert Xu commit 0ba3c026e685573bd3534c17e27da7c505ac99c4 upstream. skcipher_walk_done may be called with an error by internal or external callers. For those internal callers we shouldn't unmap pages but for external callers we must unmap any pages that are in use. This patch distinguishes between the two cases by checking whether walk->nbytes is zero or not. For internal callers, we now set walk->nbytes to zero prior to the call. For external callers, walk->nbytes has always been non-zero (as zero is used to indicate the termination of a walk). Reported-by: Ard Biesheuvel Fixes: 5cde0af2a982 ("[CRYPTO] cipher: Added block cipher type") Cc: Signed-off-by: Herbert Xu Tested-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/skcipher.c | 42 +++++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 19 deletions(-) --- a/crypto/skcipher.c +++ b/crypto/skcipher.c @@ -90,7 +90,7 @@ static inline u8 *skcipher_get_spot(u8 * return max(start, end_page); } -static void skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize) +static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize) { u8 *addr; @@ -98,19 +98,21 @@ static void skcipher_done_slow(struct sk addr = skcipher_get_spot(addr, bsize); scatterwalk_copychunks(addr, &walk->out, bsize, (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1); + return 0; } int skcipher_walk_done(struct skcipher_walk *walk, int err) { - unsigned int n; /* bytes processed */ - bool more; + unsigned int n = walk->nbytes; + unsigned int nbytes = 0; - if (unlikely(err < 0)) + if (!n) goto finish; - n = walk->nbytes - err; - walk->total -= n; - more = (walk->total != 0); + if (likely(err >= 0)) { + n -= err; + nbytes = walk->total - n; + } if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS | SKCIPHER_WALK_SLOW | @@ -126,7 +128,7 @@ unmap_src: memcpy(walk->dst.virt.addr, walk->page, n); skcipher_unmap_dst(walk); } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) { - if (err) { + if (err > 0) { /* * Didn't process all bytes. Either the algorithm is * broken, or this was the last step and it turned out @@ -134,27 +136,29 @@ unmap_src: * the algorithm requires it. */ err = -EINVAL; - goto finish; - } - skcipher_done_slow(walk, n); - goto already_advanced; + nbytes = 0; + } else + n = skcipher_done_slow(walk, n); } + if (err > 0) + err = 0; + + walk->total = nbytes; + walk->nbytes = 0; + scatterwalk_advance(&walk->in, n); scatterwalk_advance(&walk->out, n); -already_advanced: - scatterwalk_done(&walk->in, 0, more); - scatterwalk_done(&walk->out, 1, more); + scatterwalk_done(&walk->in, 0, nbytes); + scatterwalk_done(&walk->out, 1, nbytes); - if (more) { + if (nbytes) { crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ? CRYPTO_TFM_REQ_MAY_SLEEP : 0); return skcipher_walk_next(walk); } - err = 0; -finish: - walk->nbytes = 0; +finish: /* Short-circuit for the common/fast path. */ if (!((unsigned long)walk->buffer | (unsigned long)walk->page)) goto out;