From patchwork Wed Oct 13 17:16:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bodo Stroesser X-Patchwork-Id: 12556453 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA0D8C433F5 for ; Wed, 13 Oct 2021 17:16:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B36C6610CC for ; Wed, 13 Oct 2021 17:16:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237532AbhJMRSf (ORCPT ); Wed, 13 Oct 2021 13:18:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229915AbhJMRSe (ORCPT ); Wed, 13 Oct 2021 13:18:34 -0400 Received: from mail-ed1-x52c.google.com (mail-ed1-x52c.google.com [IPv6:2a00:1450:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0628BC061570; Wed, 13 Oct 2021 10:16:31 -0700 (PDT) Received: by mail-ed1-x52c.google.com with SMTP id w14so13035940edv.11; Wed, 13 Oct 2021 10:16:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id; bh=meUYWdb8BVH+ERVVUD1vNcavs7M1t/BOCZO4+emCVbE=; b=jVRR/+SbGLbMEQxv10T3/4LoFsR2rWpBdBg0FFEZ82YDaGexg+pQ0DYs97MtiPRrXf RlXvPOlqm79zVRD7/UriGjMfAL8PNkjkLb0O7mYpTbayYX9EbEi40m2TXwcVaEXQAmCH VxojX/R8cOeE6kW80Ff2ix3PfR1En00jaXM4cHOimNjeajtEqUnzp3j6LogK28xs2qf4 AMijJn7Bskfh/hFe92Jpb7Ism0G1DT4OixOa8T5VOznF4WmU0Kq+gLY/we1D5cWpy7Mh lidnCk0VQD9pt9MyaH4YsOglzBMcmq+G9+DIwI4iT7NR8WPM3c9dFWdGFhlFfXjrEkCq KC7w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=meUYWdb8BVH+ERVVUD1vNcavs7M1t/BOCZO4+emCVbE=; b=qjgLYwvN2IyX/BDD+MhRddBy9Lf/mGoNCgenpJVRsICfByrX6m328HeK6bzPJse0Y9 7i6BCJd7LZMZw3aYvVJXki+Fsf3vvv7QcuGJ9fylJdWgrJTtYVjKDQlMdVHWr/wFXJbz nTEdjttGH6YCa7ulNrzbK/+qY7mKKZdU95+bwoiPkrYDP7V/FgPW2/0PovAfQM/OxgUz 1RwCdig418xwYDg/7r8k6ODXFla4vRdXV3OyqUr3hnOFhmgAbXMjG9x05MCfFn6xZPQK tolQGbt149AlyuLz0s50xGnWkcAT8ElSGAFWhtvWJ4flMm1QSPtaEnp7dBXXFSEhhy0N LRUA== X-Gm-Message-State: AOAM530oojbRzkaHlZu/LS3lj5W31NXHLTValzpseAWmR8QOjhnSTNbk jKtpj80dQ51J9Ou+Lt8TZce8VF5uzkc= X-Google-Smtp-Source: ABdhPJz+PMeUl1mCh5APvyddfyKOozejgyineYoZpcBqqKP6ej6Yl3Au0xMYJ8USF79wBd0X0P2CPg== X-Received: by 2002:a17:906:da08:: with SMTP id fi8mr567732ejb.552.1634145389543; Wed, 13 Oct 2021 10:16:29 -0700 (PDT) Received: from localhost (ipbcc061e7.dynamic.kabel-deutschland.de. [188.192.97.231]) by smtp.gmail.com with ESMTPSA id i6sm129241ejd.57.2021.10.13.10.16.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 13 Oct 2021 10:16:29 -0700 (PDT) From: Bodo Stroesser To: "Martin K. Petersen" , Mike Christie Cc: Bodo Stroesser , linux-scsi@vger.kernel.org, target-devel@vger.kernel.org Subject: [PATCH] scsi: target: tcmu: allocate zeroed pages for data area Date: Wed, 13 Oct 2021 19:16:06 +0200 Message-Id: <20211013171606.25197-1-bostroesser@gmail.com> X-Mailer: git-send-email 2.12.3 Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org Tcmu populates the data area (used for communication with userspace) with pages that are allocated by calling alloc_page(GFP_NOIO). Therefore previous content of the allocated pages is exposed to user space. Avoid this by adding __GFP_ZERO flag. Zeroing the pages does (nearly) not affect tcmu throughput, because allocated pages are re-used for the data transfers of later SCSI cmds. Signed-off-by: Bodo Stroesser --- drivers/target/target_core_user.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index dc220fad06fa..a19e53877b0b 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -5,6 +5,7 @@ * Copyright (C) 2015 Arrikto, Inc. * Copyright (C) 2017 Chinamobile, Inc. */ +#include #include #include @@ -523,8 +524,8 @@ static inline int tcmu_get_empty_block(struct tcmu_dev *udev, rcu_read_unlock(); for (i = cnt; i < page_cnt; i++) { - /* try to get new page from the mm */ - page = alloc_page(GFP_NOIO); + /* try to get new zeroed page from the mm */ + page = alloc_page(GFP_NOIO | __GFP_ZERO); if (!page) break;