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=-6.7 required=3.0 tests=FORGED_MUA_MOZILLA, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 EEA4FC4725D for ; Wed, 6 May 2020 04:17:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D00E8206D5 for ; Wed, 6 May 2020 04:17:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725887AbgEFERN (ORCPT ); Wed, 6 May 2020 00:17:13 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:23870 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725300AbgEFERM (ORCPT ); Wed, 6 May 2020 00:17:12 -0400 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 04641vlM049077; Wed, 6 May 2020 00:17:03 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 30u8syq8vh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 May 2020 00:17:02 -0400 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 04643Uou052497; Wed, 6 May 2020 00:17:02 -0400 Received: from ppma02fra.de.ibm.com (47.49.7a9f.ip4.static.sl-reverse.com [159.122.73.71]) by mx0a-001b2d01.pphosted.com with ESMTP id 30u8syq8ty-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 May 2020 00:17:02 -0400 Received: from pps.filterd (ppma02fra.de.ibm.com [127.0.0.1]) by ppma02fra.de.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 0464578N013654; Wed, 6 May 2020 04:17:00 GMT Received: from b06avi18626390.portsmouth.uk.ibm.com (b06avi18626390.portsmouth.uk.ibm.com [9.149.26.192]) by ppma02fra.de.ibm.com with ESMTP id 30s0g5bd7j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 May 2020 04:16:59 +0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0464Fl9Z66191808 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 6 May 2020 04:15:47 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 97A5FA404D; Wed, 6 May 2020 04:16:57 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5BA32A4040; Wed, 6 May 2020 04:16:54 +0000 (GMT) Received: from localhost.localdomain (unknown [9.85.89.50]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 6 May 2020 04:16:54 +0000 (GMT) Subject: Re: [PATCH 08/11] fs: move fiemap range validation into the file systems instances To: Christoph Hellwig , linux-ext4@vger.kernel.org, viro@zeniv.linux.org.uk Cc: jack@suse.cz, tytso@mit.edu, adilger@dilger.ca, amir73il@gmail.com, linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org References: <20200505154324.3226743-1-hch@lst.de> <20200505154324.3226743-9-hch@lst.de> From: Ritesh Harjani Date: Wed, 6 May 2020 09:46:52 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20200505154324.3226743-9-hch@lst.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Message-Id: <20200506041654.5BA32A4040@d06av23.portsmouth.uk.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.676 definitions=2020-05-05_11:2020-05-04,2020-05-05 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 phishscore=0 suspectscore=0 clxscore=1015 impostorscore=0 priorityscore=1501 mlxscore=0 adultscore=0 spamscore=0 lowpriorityscore=0 malwarescore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005060026 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On 5/5/20 9:13 PM, Christoph Hellwig wrote: > Replace fiemap_check_flags with a fiemap_prep helper that also takes the > inode and mapped range, and performs the sanity check and truncation > previously done in fiemap_check_range. This way the validation is inside > the file system itself and thus properly works for the stacked overlayfs > case as well. > > Signed-off-by: Christoph Hellwig > Reviewed-by: Amir Goldstein Looks ok. Please feel free to add: Reviewed-by: Ritesh Harjani > --- > Documentation/filesystems/fiemap.txt | 12 +++--- > fs/btrfs/inode.c | 2 +- > fs/cifs/smb2ops.c | 6 ++- > fs/ext4/extents.c | 5 ++- > fs/f2fs/data.c | 3 +- > fs/ioctl.c | 63 +++++++++++----------------- > fs/iomap/fiemap.c | 2 +- > fs/nilfs2/inode.c | 2 +- > fs/ocfs2/extent_map.c | 3 +- > include/linux/fiemap.h | 3 +- > 10 files changed, 47 insertions(+), 54 deletions(-) > > diff --git a/Documentation/filesystems/fiemap.txt b/Documentation/filesystems/fiemap.txt > index ac87e6fda842b..35c8571eccb6e 100644 > --- a/Documentation/filesystems/fiemap.txt > +++ b/Documentation/filesystems/fiemap.txt > @@ -203,16 +203,18 @@ EINTR once fatal signal received. > > > Flag checking should be done at the beginning of the ->fiemap callback via the > -fiemap_check_flags() helper: > +fiemap_prep() helper: > > -int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); > +int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo, > + u64 start, u64 *len, u32 supported_flags); > > The struct fieinfo should be passed in as received from ioctl_fiemap(). The > set of fiemap flags which the fs understands should be passed via fs_flags. If > -fiemap_check_flags finds invalid user flags, it will place the bad values in > +fiemap_prep finds invalid user flags, it will place the bad values in > fieinfo->fi_flags and return -EBADR. If the file system gets -EBADR, from > -fiemap_check_flags(), it should immediately exit, returning that error back to > -ioctl_fiemap(). > +fiemap_prep(), it should immediately exit, returning that error back to > +ioctl_fiemap(). Additionally the range is validate against the supported > +maximum file size. > > > For each extent in the request range, the file system should call > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index 320d1062068d3..1f1ec361089b3 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -8250,7 +8250,7 @@ static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > { > int ret; > > - ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS); > + ret = fiemap_prep(inode, fieinfo, start, &len, BTRFS_FIEMAP_FLAGS); > if (ret) > return ret; > > diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c > index 09047f1ddfb66..828e53e795c6d 100644 > --- a/fs/cifs/smb2ops.c > +++ b/fs/cifs/smb2ops.c > @@ -3408,8 +3408,10 @@ static int smb3_fiemap(struct cifs_tcon *tcon, > int i, num, rc, flags, last_blob; > u64 next; > > - if (fiemap_check_flags(fei, FIEMAP_FLAG_SYNC)) > - return -EBADR; > + rc = fiemap_prep(d_inode(cfile->dentry), fei, start, &len, > + FIEMAP_FLAG_SYNC); > + if (rc) > + return rc; > > xid = get_xid(); > again: > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > index a41ae7c510170..41f73dea92cac 100644 > --- a/fs/ext4/extents.c > +++ b/fs/ext4/extents.c > @@ -4908,8 +4908,9 @@ int ext4_get_es_cache(struct inode *inode, struct fiemap_extent_info *fieinfo, > fieinfo->fi_flags &= ~FIEMAP_FLAG_CACHE; > } > > - if (fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC)) > - return -EBADR; > + error = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC); > + if (error) > + return error; > > error = ext4_fiemap_check_ranges(inode, start, &len); > if (error) > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 25abbbb65ba09..03faafc591b17 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -1825,7 +1825,8 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > return ret; > } > > - ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR); > + ret = fiemap_prep(inode, fieinfo, start, &len, > + FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR); > if (ret) > return ret; > > diff --git a/fs/ioctl.c b/fs/ioctl.c > index 3f300cc07dee4..56bbf02209aef 100644 > --- a/fs/ioctl.c > +++ b/fs/ioctl.c > @@ -149,61 +149,50 @@ int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical, > EXPORT_SYMBOL(fiemap_fill_next_extent); > > /** > - * fiemap_check_flags - check validity of requested flags for fiemap > + * fiemap_prep - check validity of requested flags for fiemap > + * @inode: Inode to operate on > * @fieinfo: Fiemap context passed into ->fiemap > - * @fs_flags: Set of fiemap flags that the file system understands > + * @start: Start of the mapped range > + * @len: Length of the mapped range, can be truncated by this function. > + * @supported_flags: Set of fiemap flags that the file system understands > * > - * Called from file system ->fiemap callback. This will compute the > - * intersection of valid fiemap flags and those that the fs supports. That > - * value is then compared against the user supplied flags. In case of bad user > - * flags, the invalid values will be written into the fieinfo structure, and > - * -EBADR is returned, which tells ioctl_fiemap() to return those values to > - * userspace. For this reason, a return code of -EBADR should be preserved. > + * This function must be called from each ->fiemap instance to validate the > + * fiemap request against the file system parameters. > * > - * Returns 0 on success, -EBADR on bad flags. > + * Returns 0 on success, or a negative error on failure. > */ > -int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags) > +int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo, > + u64 start, u64 *len, u32 supported_flags) > { > + u64 maxbytes = inode->i_sb->s_maxbytes; > u32 incompat_flags; > > - incompat_flags = fieinfo->fi_flags & ~(FIEMAP_FLAGS_COMPAT & fs_flags); > - if (incompat_flags) { > - fieinfo->fi_flags = incompat_flags; > - return -EBADR; > - } > - return 0; > -} > -EXPORT_SYMBOL(fiemap_check_flags); > - > -static int fiemap_check_ranges(struct super_block *sb, > - u64 start, u64 len, u64 *new_len) > -{ > - u64 maxbytes = (u64) sb->s_maxbytes; > - > - *new_len = len; > - > - if (len == 0) > + if (*len == 0) > return -EINVAL; > - > if (start > maxbytes) > return -EFBIG; > > /* > * Shrink request scope to what the fs can actually handle. > */ > - if (len > maxbytes || (maxbytes - len) < start) > - *new_len = maxbytes - start; > + if (*len > maxbytes || (maxbytes - *len) < start) > + *len = maxbytes - start; > > + supported_flags &= FIEMAP_FLAGS_COMPAT; > + incompat_flags = fieinfo->fi_flags & ~supported_flags; > + if (incompat_flags) { > + fieinfo->fi_flags = incompat_flags; > + return -EBADR; > + } > return 0; > } > +EXPORT_SYMBOL(fiemap_prep); > > static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap) > { > struct fiemap fiemap; > struct fiemap_extent_info fieinfo = { 0, }; > struct inode *inode = file_inode(filp); > - struct super_block *sb = inode->i_sb; > - u64 len; > int error; > > if (!inode->i_op->fiemap) > @@ -215,11 +204,6 @@ static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap) > if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS) > return -EINVAL; > > - error = fiemap_check_ranges(sb, fiemap.fm_start, fiemap.fm_length, > - &len); > - if (error) > - return error; > - > fieinfo.fi_flags = fiemap.fm_flags; > fieinfo.fi_extents_max = fiemap.fm_extent_count; > fieinfo.fi_extents_start = ufiemap->fm_extents; > @@ -232,7 +216,8 @@ static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap) > if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC) > filemap_write_and_wait(inode->i_mapping); > > - error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, len); > + error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, > + fiemap.fm_length); > fiemap.fm_flags = fieinfo.fi_flags; > fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped; > if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap))) > @@ -320,7 +305,7 @@ static int __generic_block_fiemap(struct inode *inode, > bool past_eof = false, whole_file = false; > int ret = 0; > > - ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC); > + ret = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC); > if (ret) > return ret; > > diff --git a/fs/iomap/fiemap.c b/fs/iomap/fiemap.c > index 449705575acf9..89dca4a97e4a2 100644 > --- a/fs/iomap/fiemap.c > +++ b/fs/iomap/fiemap.c > @@ -75,7 +75,7 @@ int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi, > ctx.fi = fi; > ctx.prev.type = IOMAP_HOLE; > > - ret = fiemap_check_flags(fi, FIEMAP_FLAG_SYNC); > + ret = fiemap_prep(inode, fi, start, &len, FIEMAP_FLAG_SYNC); > if (ret) > return ret; > > diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c > index 6e1aca38931f3..052c2da11e4d7 100644 > --- a/fs/nilfs2/inode.c > +++ b/fs/nilfs2/inode.c > @@ -1006,7 +1006,7 @@ int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > unsigned int blkbits = inode->i_blkbits; > int ret, n; > > - ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC); > + ret = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC); > if (ret) > return ret; > > diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c > index e3e2d1b2af51a..3744179b73fa1 100644 > --- a/fs/ocfs2/extent_map.c > +++ b/fs/ocfs2/extent_map.c > @@ -746,7 +746,8 @@ int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, > struct buffer_head *di_bh = NULL; > struct ocfs2_extent_rec rec; > > - ret = fiemap_check_flags(fieinfo, OCFS2_FIEMAP_FLAGS); > + ret = fiemap_prep(inode, fieinfo, map_start, &map_len, > + OCFS2_FIEMAP_FLAGS); > if (ret) > return ret; > > diff --git a/include/linux/fiemap.h b/include/linux/fiemap.h > index 240d4f7d9116a..4e624c4665837 100644 > --- a/include/linux/fiemap.h > +++ b/include/linux/fiemap.h > @@ -13,9 +13,10 @@ struct fiemap_extent_info { > fiemap_extent array */ > }; > > +int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo, > + u64 start, u64 *len, u32 supported_flags); > int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical, > u64 phys, u64 len, u32 flags); > -int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); > > int generic_block_fiemap(struct inode *inode, > struct fiemap_extent_info *fieinfo, u64 start, u64 len, >