From patchwork Mon Dec 21 02:33:34 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Gang X-Patchwork-Id: 559394 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id B294C140BA5 for ; Mon, 21 Dec 2015 13:34:41 +1100 (AEDT) Received: from localhost ([::1]:42776 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aAqJ5-0002d5-FP for incoming@patchwork.ozlabs.org; Sun, 20 Dec 2015 21:34:39 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42193) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aAqIr-0002M0-VA for qemu-devel@nongnu.org; Sun, 20 Dec 2015 21:34:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aAqIo-0005gP-JO for qemu-devel@nongnu.org; Sun, 20 Dec 2015 21:34:25 -0500 Received: from out1134-219.mail.aliyun.com ([42.120.134.219]:36801) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aAqIo-0005fj-6s for qemu-devel@nongnu.org; Sun, 20 Dec 2015 21:34:22 -0500 X-Alimail-AntiSpam: AC=CONTINUE; BC=0.09592766|-1; FP=4566689659847566807|3|1|3|0|-1|-1|-1; HT=e02c03272; MF=chengang@emindsoft.com.cn; NM=1; PH=DS; RN=8; RT=7; SR=0; TI=SMTPD_----4NCGQW9_1450665246; Received: from localhost.localdomain(mailfrom:chengang@emindsoft.com.cn ip:36.110.17.42) by smtp.aliyun-inc.com(10.147.36.219); Mon, 21 Dec 2015 10:34:13 +0800 From: chengang@emindsoft.com.cn To: riku.voipio@iki.fi, laurent@vivier.eu Date: Mon, 21 Dec 2015 10:33:34 +0800 Message-Id: <1450665214-4467-1-git-send-email-chengang@emindsoft.com.cn> X-Mailer: git-send-email 1.9.1 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 42.120.134.219 Cc: peter.maydell@linaro.org, Chen Gang , Chen Gang , qemu-devel@nongnu.org, rth@twiddle.net Subject: [Qemu-devel] [PATCH v2] linux-user/mmap.c: Always zero MAP_ANONYMOUS memory in mmap_frag() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Chen Gang When mapping MAP_ANONYMOUS memory fragments, still need notice about to set it zero, or it will cause issues. Signed-off-by: Chen Gang --- linux-user/mmap.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 7b459d5..29fe646 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -186,10 +186,12 @@ static int mmap_frag(abi_ulong real_start, if (prot_new != (prot1 | PROT_WRITE)) mprotect(host_start, qemu_host_page_size, prot_new); } else { - /* just update the protection */ if (prot_new != prot1) { mprotect(host_start, qemu_host_page_size, prot_new); } + if ((prot_new & PROT_WRITE) && ((flags & MAP_PRIVATE) || (fd == -1))) { + memset(g2h(start), 0, end - start); + } } return 0; }