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Wong" X-Patchwork-Id: 10642745 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9AA97112B for ; Tue, 16 Oct 2018 03:10:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8745A29867 for ; Tue, 16 Oct 2018 03:10:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7AEC92988C; Tue, 16 Oct 2018 03:10:46 +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=-3.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D8E5029867 for ; Tue, 16 Oct 2018 03:10:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 668446B026A; Mon, 15 Oct 2018 23:10:43 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 61A5C6B026B; Mon, 15 Oct 2018 23:10:43 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3FB0F6B026C; Mon, 15 Oct 2018 23:10:43 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-pg1-f197.google.com (mail-pg1-f197.google.com [209.85.215.197]) by kanga.kvack.org (Postfix) with ESMTP id F0ED16B026A for ; Mon, 15 Oct 2018 23:10:42 -0400 (EDT) Received: by mail-pg1-f197.google.com with SMTP id w15-v6so16161735pge.2 for ; Mon, 15 Oct 2018 20:10:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:subject:from:to:cc:date :message-id:in-reply-to:references:user-agent:mime-version :content-transfer-encoding; bh=5eu3BWWTXWnKtqnmkgUDN4s2jZ2fNj7azSAvuPl2YO0=; b=phr8h8LOdc0de9eJJ7unsg4xhVdF4Tyy7anVsnehCW08FHsb/TGMBGsRLBQ/3WyGv3 dNg0hkv40tT+Jf3YG5mCWXszN+iO9cq/wSfpi3YPRiWE0Hq4gtfhPcoXH9VTdJ2iIXs7 uKFTS+meGLcJcvTc2mzw1nrv/Jy5WhSU9u/0Lbmbv75iTdUvGay4SLnXVr05orMTSJh8 Lv8s91O8QXa+k25OHZVBpDBem5mpsRBcPKWLqVRS//gUDV51K8gAmWhjwTC7mTGfekIN FV6ddiyWZlJQ21kp8BDTWZeRhXG7d0GFbVW9Jkq3pGLBWMeP89pUE9zXjxJqw/hJ6q46 ciqQ== X-Gm-Message-State: ABuFfohEwxLwLIcALa7n1bRg/X+SLIugroSSDdLQR2RLmr1QBZz1+Rbk lTh0Yz3n17N/rojzgijKTtqVreQbGkA/nHo7BtPmCOceOXfZ8q2D69IBg+NlOUJK1O/86SeifnF 0bteKChbVLzabkQdPXygtGTjcDz7Rh7YtfcAt18VM+5f3dX0yBgoO5Gg49GDboxAkCg== X-Received: by 2002:a65:4145:: with SMTP id x5-v6mr18435050pgp.309.1539659442612; Mon, 15 Oct 2018 20:10:42 -0700 (PDT) X-Google-Smtp-Source: ACcGV60QT6DZCzZD25Egz+6pxPzOwXKsSX6X5FrLpIWlOb+Q1TcF6+8TTF0SuDJ0H73uRDDHL6Fw X-Received: by 2002:a65:4145:: with SMTP id x5-v6mr18435022pgp.309.1539659441830; Mon, 15 Oct 2018 20:10:41 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1539659441; cv=none; d=google.com; s=arc-20160816; b=cOWqsIgYvcizA4IE05jZIx0aVutkPaKQTUVMt0iLRLEqBtqkHfEcGyrxI3nNbuFwQa nqG56e0cbk29JHnCHT2RnQK30aX4gZynqNwu0aiwQ0vsHUxJz9gV+/gbsVfVQsapeqD0 DuW9mRCXserb4WDloENiyLnfG0YL2hYtWYQu5JWSBia0LCfa76b95QIAT78WkWWiUocf J+XSXOJtRlIaBnSlITy2x2TSBv7Eln2xreAoohWptkUU+bVMApbewSNkb/6aLXNXNT45 F3ucdN9vNDX8LpfZwlImTcRgIt3K66+1cifkPGb+Hh0E4zoa/5WdrmHuOLMYWZNxV13G dK7Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:mime-version:user-agent:references :in-reply-to:message-id:date:cc:to:from:subject:dkim-signature; bh=5eu3BWWTXWnKtqnmkgUDN4s2jZ2fNj7azSAvuPl2YO0=; b=qhooKiF9s/DLK1VpNdOpWl4uwD//cAty6I9rIqep3Fkkv/WkPuqJkmWOzlmo+h8IB5 2X+wfyf+Xt4TI44VwBKBVZ5ovVSzSUXVt+obb0U78SOz8UkdAfXFZBomSL3Romp+8+Qa DpGPFMVZsFNdH1W4cInFfCyIBLfd7Rf4AfAjzf+mU4jrHnscLAZgZDcNTKN9Iwo7HWtG ZmbHieD4F6V8TNokEkJV77UDG28acWxDAJ2ylYyJUyfq1Tk158bHEEW4JrZDxrwQXLCM quPaaczTrWa8zIpigin51gUr7Xk8M70SGZlGfJt4mQKAUO37dwn+FAtE0cba2iha/EKI L7uA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2018-07-02 header.b="WmRiD6H/"; spf=pass (google.com: domain of darrick.wong@oracle.com designates 141.146.126.78 as permitted sender) smtp.mailfrom=darrick.wong@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: from aserp2120.oracle.com (aserp2120.oracle.com. [141.146.126.78]) by mx.google.com with ESMTPS id f10-v6si12920816pgl.148.2018.10.15.20.10.41 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 15 Oct 2018 20:10:41 -0700 (PDT) Received-SPF: pass (google.com: domain of darrick.wong@oracle.com designates 141.146.126.78 as permitted sender) client-ip=141.146.126.78; Authentication-Results: mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2018-07-02 header.b="WmRiD6H/"; spf=pass (google.com: domain of darrick.wong@oracle.com designates 141.146.126.78 as permitted sender) smtp.mailfrom=darrick.wong@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9G38Tar053313; Tue, 16 Oct 2018 03:10:39 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : in-reply-to : references : mime-version : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=5eu3BWWTXWnKtqnmkgUDN4s2jZ2fNj7azSAvuPl2YO0=; b=WmRiD6H/JOP7jYhQwOlVje+i+ETuilfxpewXFRKf6ZP88jdx+CNv1fToYZrnHpIRQZCC cnkWiRl7SeyihP2e+MJUHD0NjjhZq2RXOyYjhLDUOS5i24KMNR3RD+9DdXGFAn/xgygX GZPX3To4YCXFd9kf9YT8od5fEydfRhgg6/X/xwceftvSQgd7xkqiXNHEB3ea1Beua5NJ uTmFI2kJE1cfpchbnrzdRlqn33cqye5AjlBSrX4JusVJp5RlxSLv06cRIPXWUMPAhTrt d+QFCu3gI4eATezsx9ymqnbGE9hQhneAde1U0SU+Hg43pF7dm5n00UnrVo0pFF4z+YWM kg== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp2120.oracle.com with ESMTP id 2n38npwuw4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 16 Oct 2018 03:10:39 +0000 Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w9G3AXRP010240 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 16 Oct 2018 03:10:33 GMT Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w9G3AWXw009132; Tue, 16 Oct 2018 03:10:32 GMT Received: from localhost (/10.159.227.150) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 15 Oct 2018 20:10:32 -0700 Subject: [PATCH 05/26] vfs: strengthen checking of file range inputs to generic_remap_checks From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, Amir Goldstein , linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christoph Hellwig , ocfs2-devel@oss.oracle.com Date: Mon, 15 Oct 2018 20:10:30 -0700 Message-ID: <153965943066.1256.17049880978132186525.stgit@magnolia> In-Reply-To: <153965939489.1256.7400115244528045860.stgit@magnolia> References: <153965939489.1256.7400115244528045860.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9047 signatures=668706 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810160026 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP From: Darrick J. Wong File range remapping, if allowed to run past the destination file's EOF, is an optimization on a regular file write. Regular file writes that extend the file length are subject to various constraints which are not checked by range cloning. This is a correctness problem because we're never allowed to touch ranges that the page cache can't support (s_maxbytes); we're not supposed to deal with large offsets (MAX_NON_LFS) if O_LARGEFILE isn't set; and we must obey resource limits (RLIMIT_FSIZE). Therefore, add these checks to the new generic_remap_checks function so that we curtail unexpected behavior. Signed-off-by: Darrick J. Wong Reviewed-by: Amir Goldstein Reviewed-by: Christoph Hellwig --- mm/filemap.c | 91 ++++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 59 insertions(+), 32 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 47e6bfd45a91..08ad210fee49 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2915,6 +2915,49 @@ struct page *read_cache_page_gfp(struct address_space *mapping, } EXPORT_SYMBOL(read_cache_page_gfp); +static int generic_access_check_limits(struct file *file, loff_t pos, + loff_t *count) +{ + struct inode *inode = file->f_mapping->host; + + /* Don't exceed the LFS limits. */ + if (unlikely(pos + *count > MAX_NON_LFS && + !(file->f_flags & O_LARGEFILE))) { + if (pos >= MAX_NON_LFS) + return -EFBIG; + *count = min(*count, (loff_t)MAX_NON_LFS - pos); + } + + /* + * Don't operate on ranges the page cache doesn't support. + * + * If we have written data it becomes a short write. If we have + * exceeded without writing data we send a signal and return EFBIG. + * Linus frestrict idea will clean these up nicely.. + */ + if (unlikely(pos >= inode->i_sb->s_maxbytes)) + return -EFBIG; + + *count = min(*count, inode->i_sb->s_maxbytes - pos); + return 0; +} + +static int generic_write_check_limits(struct file *file, loff_t pos, + loff_t *count) +{ + unsigned long limit = rlimit(RLIMIT_FSIZE); + + if (limit != RLIM_INFINITY) { + if (pos >= limit) { + send_sig(SIGXFSZ, current, 0); + return -EFBIG; + } + *count = min(*count, (loff_t)limit - pos); + } + + return generic_access_check_limits(file, pos, count); +} + /* * Performs necessary checks before doing a write * @@ -2926,8 +2969,8 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; - unsigned long limit = rlimit(RLIMIT_FSIZE); - loff_t pos; + loff_t count; + int ret; if (!iov_iter_count(from)) return 0; @@ -2936,40 +2979,15 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) if (iocb->ki_flags & IOCB_APPEND) iocb->ki_pos = i_size_read(inode); - pos = iocb->ki_pos; - if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) return -EINVAL; - if (limit != RLIM_INFINITY) { - if (iocb->ki_pos >= limit) { - send_sig(SIGXFSZ, current, 0); - return -EFBIG; - } - iov_iter_truncate(from, limit - (unsigned long)pos); - } + count = iov_iter_count(from); + ret = generic_write_check_limits(file, iocb->ki_pos, &count); + if (ret) + return ret; - /* - * LFS rule - */ - if (unlikely(pos + iov_iter_count(from) > MAX_NON_LFS && - !(file->f_flags & O_LARGEFILE))) { - if (pos >= MAX_NON_LFS) - return -EFBIG; - iov_iter_truncate(from, MAX_NON_LFS - (unsigned long)pos); - } - - /* - * Are we about to exceed the fs block limit ? - * - * If we have written data it becomes a short write. If we have - * exceeded without writing data we send a signal and return EFBIG. - * Linus frestrict idea will clean these up nicely.. - */ - if (unlikely(pos >= inode->i_sb->s_maxbytes)) - return -EFBIG; - - iov_iter_truncate(from, inode->i_sb->s_maxbytes - pos); + iov_iter_truncate(from, count); return iov_iter_count(from); } EXPORT_SYMBOL(generic_write_checks); @@ -2991,6 +3009,7 @@ int generic_remap_checks(struct file *file_in, loff_t pos_in, uint64_t bcount; loff_t size_in, size_out; loff_t bs = inode_out->i_sb->s_blocksize; + int ret; /* The start of both ranges must be aligned to an fs block. */ if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_out, bs)) @@ -3014,6 +3033,14 @@ int generic_remap_checks(struct file *file_in, loff_t pos_in, return -EINVAL; count = min(count, size_in - (uint64_t)pos_in); + ret = generic_access_check_limits(file_in, pos_in, &count); + if (ret) + return ret; + + ret = generic_write_check_limits(file_out, pos_out, &count); + if (ret) + return ret; + /* * If the user wanted us to link to the infile's EOF, round up to the * next block boundary for this check.