linux/fs/xfs/xfs_pnfs.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2014 Christoph Hellwig.
*/
#include "xfs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_bmap.h"
#include "xfs_iomap.h"
#include "xfs_pnfs.h"
/*
* Ensure that we do not have any outstanding pNFS layouts that can be used by
* clients to directly read from or write to this inode. This must be called
* before every operation that can remove blocks from the extent map.
* Additionally we call it during the write operation, where aren't concerned
* about exposing unallocated blocks but just want to provide basic
* synchronization between a local writer and pNFS clients. mmap writes would
* also benefit from this sort of synchronization, but due to the tricky locking
* rules in the page fault path we don't bother.
*/
int
xfs: prepare xfs_break_layouts() for another layout type When xfs is operating as the back-end of a pNFS block server, it prevents collisions between local and remote operations by requiring a lease to be held for remotely accessed blocks. Local filesystem operations break those leases before writing or mutating the extent map of the file. A similar mechanism is needed to prevent operations on pinned dax mappings, like device-DMA, from colliding with extent unmap operations. BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of layout breaking. Layouts are broken in the BREAK_WRITE case to ensure that layout-holders do not collide with local writes. Additionally, layouts are broken in the BREAK_UNMAP case to make sure the layout-holder has a consistent view of the file's extent map. While BREAK_WRITE breaks can be satisfied be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL. After this refactoring xfs_break_layouts() becomes the entry point for coordinating both types of breaks. Finally, xfs_break_leased_layouts() becomes just the BREAK_WRITE handler. Note that the unlock tracking is needed in a follow on change. That will coordinate retrying either break handler until both successfully test for a lease break while maintaining the lock state. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-20 21:42:38 +00:00
xfs_break_leased_layouts(
struct inode *inode,
xfs: prepare xfs_break_layouts() for another layout type When xfs is operating as the back-end of a pNFS block server, it prevents collisions between local and remote operations by requiring a lease to be held for remotely accessed blocks. Local filesystem operations break those leases before writing or mutating the extent map of the file. A similar mechanism is needed to prevent operations on pinned dax mappings, like device-DMA, from colliding with extent unmap operations. BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of layout breaking. Layouts are broken in the BREAK_WRITE case to ensure that layout-holders do not collide with local writes. Additionally, layouts are broken in the BREAK_UNMAP case to make sure the layout-holder has a consistent view of the file's extent map. While BREAK_WRITE breaks can be satisfied be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL. After this refactoring xfs_break_layouts() becomes the entry point for coordinating both types of breaks. Finally, xfs_break_leased_layouts() becomes just the BREAK_WRITE handler. Note that the unlock tracking is needed in a follow on change. That will coordinate retrying either break handler until both successfully test for a lease break while maintaining the lock state. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-20 21:42:38 +00:00
uint *iolock,
bool *did_unlock)
{
struct xfs_inode *ip = XFS_I(inode);
int error;
while ((error = break_layout(inode, false)) == -EWOULDBLOCK) {
xfs_iunlock(ip, *iolock);
xfs: prepare xfs_break_layouts() for another layout type When xfs is operating as the back-end of a pNFS block server, it prevents collisions between local and remote operations by requiring a lease to be held for remotely accessed blocks. Local filesystem operations break those leases before writing or mutating the extent map of the file. A similar mechanism is needed to prevent operations on pinned dax mappings, like device-DMA, from colliding with extent unmap operations. BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of layout breaking. Layouts are broken in the BREAK_WRITE case to ensure that layout-holders do not collide with local writes. Additionally, layouts are broken in the BREAK_UNMAP case to make sure the layout-holder has a consistent view of the file's extent map. While BREAK_WRITE breaks can be satisfied be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL. After this refactoring xfs_break_layouts() becomes the entry point for coordinating both types of breaks. Finally, xfs_break_leased_layouts() becomes just the BREAK_WRITE handler. Note that the unlock tracking is needed in a follow on change. That will coordinate retrying either break handler until both successfully test for a lease break while maintaining the lock state. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-20 21:42:38 +00:00
*did_unlock = true;
error = break_layout(inode, true);
*iolock &= ~XFS_IOLOCK_SHARED;
*iolock |= XFS_IOLOCK_EXCL;
xfs_ilock(ip, *iolock);
}
return error;
}
/*
* Get a unique ID including its location so that the client can identify
* the exported device.
*/
int
xfs_fs_get_uuid(
struct super_block *sb,
u8 *buf,
u32 *len,
u64 *offset)
{
struct xfs_mount *mp = XFS_M(sb);
xfs_notice_once(mp,
"Using experimental pNFS feature, use at your own risk!");
if (*len < sizeof(uuid_t))
return -EINVAL;
memcpy(buf, &mp->m_sb.sb_uuid, sizeof(uuid_t));
*len = sizeof(uuid_t);
*offset = offsetof(struct xfs_dsb, sb_uuid);
return 0;
}
/*
* We cannot use file based VFS helpers such as file_modified() to update
* inode state as we modify the data/metadata in the inode here. Hence we have
* to open code the timestamp updates and SUID/SGID stripping. We also need
* to set the inode prealloc flag to ensure that the extents we allocate are not
* removed if the inode is reclaimed from memory before xfs_fs_block_commit()
* is from the client to indicate that data has been written and the file size
* can be extended.
*/
static int
xfs_fs_map_update_inode(
struct xfs_inode *ip)
{
struct xfs_trans *tp;
int error;
error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_writeid,
0, 0, 0, &tp);
if (error)
return error;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
VFS_I(ip)->i_mode &= ~S_ISUID;
if (VFS_I(ip)->i_mode & S_IXGRP)
VFS_I(ip)->i_mode &= ~S_ISGID;
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
ip->i_diflags |= XFS_DIFLAG_PREALLOC;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
return xfs_trans_commit(tp);
}
/*
* Get a layout for the pNFS client.
*/
int
xfs_fs_map_blocks(
struct inode *inode,
loff_t offset,
u64 length,
struct iomap *iomap,
bool write,
u32 *device_generation)
{
struct xfs_inode *ip = XFS_I(inode);
struct xfs_mount *mp = ip->i_mount;
struct xfs_bmbt_irec imap;
xfs_fileoff_t offset_fsb, end_fsb;
loff_t limit;
int bmapi_flags = XFS_BMAPI_ENTIRE;
int nimaps = 1;
uint lock_flags;
int error = 0;
u64 seq;
if (xfs_is_shutdown(mp))
return -EIO;
/*
* We can't export inodes residing on the realtime device. The realtime
* device doesn't have a UUID to identify it, so the client has no way
* to find it.
*/
if (XFS_IS_REALTIME_INODE(ip))
return -ENXIO;
/*
* The pNFS block layout spec actually supports reflink like
* functionality, but the Linux pNFS server doesn't implement it yet.
*/
if (xfs_is_reflink_inode(ip))
return -ENXIO;
/*
* Lock out any other I/O before we flush and invalidate the pagecache,
* and then hand out a layout to the remote system. This is very
* similar to direct I/O, except that the synchronization is much more
xfs: prepare xfs_break_layouts() for another layout type When xfs is operating as the back-end of a pNFS block server, it prevents collisions between local and remote operations by requiring a lease to be held for remotely accessed blocks. Local filesystem operations break those leases before writing or mutating the extent map of the file. A similar mechanism is needed to prevent operations on pinned dax mappings, like device-DMA, from colliding with extent unmap operations. BREAK_WRITE and BREAK_UNMAP are introduced as two distinct levels of layout breaking. Layouts are broken in the BREAK_WRITE case to ensure that layout-holders do not collide with local writes. Additionally, layouts are broken in the BREAK_UNMAP case to make sure the layout-holder has a consistent view of the file's extent map. While BREAK_WRITE breaks can be satisfied be recalling FL_LAYOUT leases, BREAK_UNMAP breaks additionally require waiting for busy dax-pages to go idle while holding XFS_MMAPLOCK_EXCL. After this refactoring xfs_break_layouts() becomes the entry point for coordinating both types of breaks. Finally, xfs_break_leased_layouts() becomes just the BREAK_WRITE handler. Note that the unlock tracking is needed in a follow on change. That will coordinate retrying either break handler until both successfully test for a lease break while maintaining the lock state. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: "Darrick J. Wong" <darrick.wong@oracle.com> Reported-by: Dave Chinner <david@fromorbit.com> Reported-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-20 21:42:38 +00:00
* complicated. See the comment near xfs_break_leased_layouts
* for a detailed explanation.
*/
xfs_ilock(ip, XFS_IOLOCK_EXCL);
error = -EINVAL;
limit = mp->m_super->s_maxbytes;
if (!write)
limit = max(limit, round_up(i_size_read(inode),
inode->i_sb->s_blocksize));
if (offset > limit)
goto out_unlock;
if (offset > limit - length)
length = limit - offset;
error = filemap_write_and_wait(inode->i_mapping);
if (error)
goto out_unlock;
error = invalidate_inode_pages2(inode->i_mapping);
if (WARN_ON_ONCE(error))
goto out_unlock;
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + length);
offset_fsb = XFS_B_TO_FSBT(mp, offset);
lock_flags = xfs_ilock_data_map_shared(ip);
error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb,
&imap, &nimaps, bmapi_flags);
seq = xfs_iomap_inode_sequence(ip, 0);
ASSERT(!nimaps || imap.br_startblock != DELAYSTARTBLOCK);
if (!error && write &&
(!nimaps || imap.br_startblock == HOLESTARTBLOCK)) {
if (offset + length > XFS_ISIZE(ip))
end_fsb = xfs_iomap_eof_align_last_fsb(ip, end_fsb);
else if (nimaps && imap.br_startblock == HOLESTARTBLOCK)
end_fsb = min(end_fsb, imap.br_startoff +
imap.br_blockcount);
xfs_iunlock(ip, lock_flags);
error = xfs_iomap_write_direct(ip, offset_fsb,
end_fsb - offset_fsb, 0, &imap, &seq);
if (error)
goto out_unlock;
/*
* Ensure the next transaction is committed synchronously so
* that the blocks allocated and handed out to the client are
* guaranteed to be present even after a server crash.
*/
error = xfs_fs_map_update_inode(ip);
if (!error)
error = xfs_log_force_inode(ip);
if (error)
goto out_unlock;
} else {
xfs_iunlock(ip, lock_flags);
}
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
error = xfs_bmbt_to_iomap(ip, iomap, &imap, 0, 0, seq);
*device_generation = mp->m_generation;
return error;
out_unlock:
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}
/*
* Ensure the size update falls into a valid allocated block.
*/
static int
xfs_pnfs_validate_isize(
struct xfs_inode *ip,
xfs_off_t isize)
{
struct xfs_bmbt_irec imap;
int nimaps = 1;
int error = 0;
xfs_ilock(ip, XFS_ILOCK_SHARED);
error = xfs_bmapi_read(ip, XFS_B_TO_FSBT(ip->i_mount, isize - 1), 1,
&imap, &nimaps, 0);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (error)
return error;
if (imap.br_startblock == HOLESTARTBLOCK ||
imap.br_startblock == DELAYSTARTBLOCK ||
imap.br_state == XFS_EXT_UNWRITTEN)
return -EIO;
return 0;
}
/*
* Make sure the blocks described by maps are stable on disk. This includes
* converting any unwritten extents, flushing the disk cache and updating the
* time stamps.
*
* Note that we rely on the caller to always send us a timestamp update so that
* we always commit a transaction here. If that stops being true we will have
* to manually flush the cache here similar to what the fsync code path does
* for datasyncs on files that have no dirty metadata.
*/
int
xfs_fs_commit_blocks(
struct inode *inode,
struct iomap *maps,
int nr_maps,
struct iattr *iattr)
{
struct xfs_inode *ip = XFS_I(inode);
struct xfs_mount *mp = ip->i_mount;
struct xfs_trans *tp;
bool update_isize = false;
int error, i;
loff_t size;
ASSERT(iattr->ia_valid & (ATTR_ATIME|ATTR_CTIME|ATTR_MTIME));
xfs_ilock(ip, XFS_IOLOCK_EXCL);
size = i_size_read(inode);
if ((iattr->ia_valid & ATTR_SIZE) && iattr->ia_size > size) {
update_isize = true;
size = iattr->ia_size;
}
for (i = 0; i < nr_maps; i++) {
u64 start, length, end;
start = maps[i].offset;
if (start > size)
continue;
end = start + maps[i].length;
if (end > size)
end = size;
length = end - start;
if (!length)
continue;
/*
* Make sure reads through the pagecache see the new data.
*/
error = invalidate_inode_pages2_range(inode->i_mapping,
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 12:29:47 +00:00
start >> PAGE_SHIFT,
(end - 1) >> PAGE_SHIFT);
WARN_ON_ONCE(error);
error = xfs_iomap_write_unwritten(ip, start, length, false);
if (error)
goto out_drop_iolock;
}
if (update_isize) {
error = xfs_pnfs_validate_isize(ip, size);
if (error)
goto out_drop_iolock;
}
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
if (error)
goto out_drop_iolock;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
xfs: use setattr_copy to set vfs inode attributes Filipe Manana pointed out that XFS' behavior w.r.t. setuid/setgid revocation isn't consistent with btrfs[1] or ext4. Those two filesystems use the VFS function setattr_copy to convey certain attributes from struct iattr into the VFS inode structure. Andrey Zhadchenko reported[2] that XFS uses the wrong user namespace to decide if it should clear setgid and setuid on a file attribute update. This is a second symptom of the problem that Filipe noticed. XFS, on the other hand, open-codes setattr_copy in xfs_setattr_mode, xfs_setattr_nonsize, and xfs_setattr_time. Regrettably, setattr_copy is /not/ a simple copy function; it contains additional logic to clear the setgid bit when setting the mode, and XFS' version no longer matches. The VFS implements its own setuid/setgid stripping logic, which establishes consistent behavior. It's a tad unfortunate that it's scattered across notify_change, should_remove_suid, and setattr_copy but XFS should really follow the Linux VFS. Adapt XFS to use the VFS functions and get rid of the old functions. [1] https://lore.kernel.org/fstests/CAL3q7H47iNQ=Wmk83WcGB-KBJVOEtR9+qGczzCeXJ9Y2KCV25Q@mail.gmail.com/ [2] https://lore.kernel.org/linux-xfs/20220221182218.748084-1-andrey.zhadchenko@virtuozzo.com/ Fixes: 7fa294c8991c ("userns: Allow chown and setgid preservation") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org>
2022-03-08 18:51:16 +00:00
ASSERT(!(iattr->ia_valid & (ATTR_UID | ATTR_GID)));
setattr_copy(&nop_mnt_idmap, inode, iattr);
if (update_isize) {
i_size_write(inode, iattr->ia_size);
ip->i_disk_size = iattr->ia_size;
}
xfs_trans_set_sync(tp);
error = xfs_trans_commit(tp);
out_drop_iolock:
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
return error;
}