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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 autolearn=ham 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 7C9AFC2D0CE for ; Tue, 21 Jan 2020 17:46:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 50D5E22522 for ; Tue, 21 Jan 2020 17:46:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="JKg3U0/m" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729205AbgAURqC (ORCPT ); Tue, 21 Jan 2020 12:46:02 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:53792 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728186AbgAURqC (ORCPT ); Tue, 21 Jan 2020 12:46:02 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id 00LHcALr143931; Tue, 21 Jan 2020 17:45:58 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2019-08-05; bh=KpS6xwrKyWJhk7DQPJTgXp+GQ0Sk4zF24Zkn8ftRw6o=; b=JKg3U0/mxjH94uFy0wzmV1apfVhn2YR0ZYMOSiSUkJ+BYw7FLSVK0bbqwsI79Ij7vgDl wnwNz4j8Hd83WGAcx+kel5fkzjtQQWP7TK/1X8gj9kHdpdb+dIRd3TRs838K31x/b3pw 887fZFi1heNd6kHbzaezjEQLCuNsiy8+LfjfuwnQX9QYQuuKkRqgM7SBM6HDoRnfnxpO v6fO36akNb2WuM8jFjeXbxazStv3U+F3kY9xx5TJ6NRdcApoaqB571vbnvkPQDJmwBux aD9nbX+7bgYpwrSMkxU5Ws5XD5K0uHE4U0bdvUAvXTsgnQHKcaS9hE4iE2hoxjJQraBH Wg== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by userp2120.oracle.com with ESMTP id 2xktnr6hr4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 21 Jan 2020 17:45:58 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id 00LHd9Im156307; Tue, 21 Jan 2020 17:45:57 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userp3030.oracle.com with ESMTP id 2xnsa936yt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 21 Jan 2020 17:45:57 +0000 Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 00LHjuaH017472; Tue, 21 Jan 2020 17:45:56 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 21 Jan 2020 09:45:56 -0800 Date: Tue, 21 Jan 2020 09:45:55 -0800 From: "Darrick J. Wong" To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org, Allison Collins Subject: Re: [PATCH 04/29] xfs: use strndup_user in XFS_IOC_ATTRMULTI_BY_HANDLE Message-ID: <20200121174555.GE8247@magnolia> References: <20200114081051.297488-1-hch@lst.de> <20200114081051.297488-5-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200114081051.297488-5-hch@lst.de> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9507 signatures=668685 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=8.0.1-1911140001 definitions=main-2001210136 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9507 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-2001210136 Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Jan 14, 2020 at 09:10:26AM +0100, Christoph Hellwig wrote: > Simplify the user copy code by using strndup_user. This means that we > now do one memory allocation per operation instead of one per ioctl, > but memory allocations are cheap compared to the actual file system > operations. > > Signed-off-by: Christoph Hellwig Looks ok, Reviewed-by: Darrick J. Wong --D > --- > fs/xfs/xfs_ioctl.c | 17 +++++------------ > fs/xfs/xfs_ioctl32.c | 17 +++++------------ > 2 files changed, 10 insertions(+), 24 deletions(-) > > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > index 6bd0684a3528..f4d5c865e29e 100644 > --- a/fs/xfs/xfs_ioctl.c > +++ b/fs/xfs/xfs_ioctl.c > @@ -446,11 +446,6 @@ xfs_attrmulti_by_handle( > goto out_dput; > } > > - error = -ENOMEM; > - attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL); > - if (!attr_name) > - goto out_kfree_ops; > - > error = 0; > for (i = 0; i < am_hreq.opcount; i++) { > if ((ops[i].am_flags & ATTR_ROOT) && > @@ -460,12 +455,11 @@ xfs_attrmulti_by_handle( > } > ops[i].am_flags &= ~ATTR_KERNEL_FLAGS; > > - ops[i].am_error = strncpy_from_user((char *)attr_name, > - ops[i].am_attrname, MAXNAMELEN); > - if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN) > - error = -ERANGE; > - if (ops[i].am_error < 0) > + attr_name = strndup_user(ops[i].am_attrname, MAXNAMELEN); > + if (IS_ERR(attr_name)) { > + ops[i].am_error = PTR_ERR(attr_name); > break; > + } > > switch (ops[i].am_opcode) { > case ATTR_OP_GET: > @@ -496,13 +490,12 @@ xfs_attrmulti_by_handle( > default: > ops[i].am_error = -EINVAL; > } > + kfree(attr_name); > } > > if (copy_to_user(am_hreq.ops, ops, size)) > error = -EFAULT; > > - kfree(attr_name); > - out_kfree_ops: > kfree(ops); > out_dput: > dput(dentry); > diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c > index 1092c66e48d6..e6a7f619a54c 100644 > --- a/fs/xfs/xfs_ioctl32.c > +++ b/fs/xfs/xfs_ioctl32.c > @@ -443,11 +443,6 @@ xfs_compat_attrmulti_by_handle( > goto out_dput; > } > > - error = -ENOMEM; > - attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL); > - if (!attr_name) > - goto out_kfree_ops; > - > error = 0; > for (i = 0; i < am_hreq.opcount; i++) { > if ((ops[i].am_flags & ATTR_ROOT) && > @@ -457,13 +452,12 @@ xfs_compat_attrmulti_by_handle( > } > ops[i].am_flags &= ~ATTR_KERNEL_FLAGS; > > - ops[i].am_error = strncpy_from_user((char *)attr_name, > - compat_ptr(ops[i].am_attrname), > + attr_name = strndup_user(compat_ptr(ops[i].am_attrname), > MAXNAMELEN); > - if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN) > - error = -ERANGE; > - if (ops[i].am_error < 0) > + if (IS_ERR(attr_name)) { > + ops[i].am_error = PTR_ERR(attr_name); > break; > + } > > switch (ops[i].am_opcode) { > case ATTR_OP_GET: > @@ -494,13 +488,12 @@ xfs_compat_attrmulti_by_handle( > default: > ops[i].am_error = -EINVAL; > } > + kfree(attr_name); > } > > if (copy_to_user(compat_ptr(am_hreq.ops), ops, size)) > error = -EFAULT; > > - kfree(attr_name); > - out_kfree_ops: > kfree(ops); > out_dput: > dput(dentry); > -- > 2.24.1 >