linux/fs/reiserfs/xattr.c
Greg Kroah-Hartman b24413180f 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>
2017-11-02 11:10:55 +01:00

1010 lines
24 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/reiserfs/xattr.c
*
* Copyright (c) 2002 by Jeff Mahoney, <jeffm@suse.com>
*
*/
/*
* In order to implement EA/ACLs in a clean, backwards compatible manner,
* they are implemented as files in a "private" directory.
* Each EA is in it's own file, with the directory layout like so (/ is assumed
* to be relative to fs root). Inside the /.reiserfs_priv/xattrs directory,
* directories named using the capital-hex form of the objectid and
* generation number are used. Inside each directory are individual files
* named with the name of the extended attribute.
*
* So, for objectid 12648430, we could have:
* /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_access
* /.reiserfs_priv/xattrs/C0FFEE.0/system.posix_acl_default
* /.reiserfs_priv/xattrs/C0FFEE.0/user.Content-Type
* .. or similar.
*
* The file contents are the text of the EA. The size is known based on the
* stat data describing the file.
*
* In the case of system.posix_acl_access and system.posix_acl_default, since
* these are special cases for filesystem ACLs, they are interpreted by the
* kernel, in addition, they are negatively and positively cached and attached
* to the inode so that unnecessary lookups are avoided.
*
* Locking works like so:
* Directory components (xattr root, xattr dir) are protectd by their i_mutex.
* The xattrs themselves are protected by the xattr_sem.
*/
#include "reiserfs.h"
#include <linux/capability.h>
#include <linux/dcache.h>
#include <linux/namei.h>
#include <linux/errno.h>
#include <linux/gfp.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include "xattr.h"
#include "acl.h"
#include <linux/uaccess.h>
#include <net/checksum.h>
#include <linux/stat.h>
#include <linux/quotaops.h>
#include <linux/security.h>
#include <linux/posix_acl_xattr.h>
#define PRIVROOT_NAME ".reiserfs_priv"
#define XAROOT_NAME "xattrs"
/*
* Helpers for inode ops. We do this so that we don't have all the VFS
* overhead and also for proper i_mutex annotation.
* dir->i_mutex must be held for all of them.
*/
#ifdef CONFIG_REISERFS_FS_XATTR
static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
{
BUG_ON(!inode_is_locked(dir));
return dir->i_op->create(dir, dentry, mode, true);
}
#endif
static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
BUG_ON(!inode_is_locked(dir));
return dir->i_op->mkdir(dir, dentry, mode);
}
/*
* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
* mutation ops aren't called during rename or splace, which are the
* only other users of I_MUTEX_CHILD. It violates the ordering, but that's
* better than allocating another subclass just for this code.
*/
static int xattr_unlink(struct inode *dir, struct dentry *dentry)
{
int error;
BUG_ON(!inode_is_locked(dir));
inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD);
error = dir->i_op->unlink(dir, dentry);
inode_unlock(d_inode(dentry));
if (!error)
d_delete(dentry);
return error;
}
static int xattr_rmdir(struct inode *dir, struct dentry *dentry)
{
int error;
BUG_ON(!inode_is_locked(dir));
inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD);
error = dir->i_op->rmdir(dir, dentry);
if (!error)
d_inode(dentry)->i_flags |= S_DEAD;
inode_unlock(d_inode(dentry));
if (!error)
d_delete(dentry);
return error;
}
#define xattr_may_create(flags) (!flags || flags & XATTR_CREATE)
static struct dentry *open_xa_root(struct super_block *sb, int flags)
{
struct dentry *privroot = REISERFS_SB(sb)->priv_root;
struct dentry *xaroot;
if (d_really_is_negative(privroot))
return ERR_PTR(-ENODATA);
inode_lock_nested(d_inode(privroot), I_MUTEX_XATTR);
xaroot = dget(REISERFS_SB(sb)->xattr_root);
if (!xaroot)
xaroot = ERR_PTR(-ENODATA);
else if (d_really_is_negative(xaroot)) {
int err = -ENODATA;
if (xattr_may_create(flags))
err = xattr_mkdir(d_inode(privroot), xaroot, 0700);
if (err) {
dput(xaroot);
xaroot = ERR_PTR(err);
}
}
inode_unlock(d_inode(privroot));
return xaroot;
}
static struct dentry *open_xa_dir(const struct inode *inode, int flags)
{
struct dentry *xaroot, *xadir;
char namebuf[17];
xaroot = open_xa_root(inode->i_sb, flags);
if (IS_ERR(xaroot))
return xaroot;
snprintf(namebuf, sizeof(namebuf), "%X.%X",
le32_to_cpu(INODE_PKEY(inode)->k_objectid),
inode->i_generation);
inode_lock_nested(d_inode(xaroot), I_MUTEX_XATTR);
xadir = lookup_one_len(namebuf, xaroot, strlen(namebuf));
if (!IS_ERR(xadir) && d_really_is_negative(xadir)) {
int err = -ENODATA;
if (xattr_may_create(flags))
err = xattr_mkdir(d_inode(xaroot), xadir, 0700);
if (err) {
dput(xadir);
xadir = ERR_PTR(err);
}
}
inode_unlock(d_inode(xaroot));
dput(xaroot);
return xadir;
}
/*
* The following are side effects of other operations that aren't explicitly
* modifying extended attributes. This includes operations such as permissions
* or ownership changes, object deletions, etc.
*/
struct reiserfs_dentry_buf {
struct dir_context ctx;
struct dentry *xadir;
int count;
struct dentry *dentries[8];
};
static int
fill_with_dentries(struct dir_context *ctx, const char *name, int namelen,
loff_t offset, u64 ino, unsigned int d_type)
{
struct reiserfs_dentry_buf *dbuf =
container_of(ctx, struct reiserfs_dentry_buf, ctx);
struct dentry *dentry;
WARN_ON_ONCE(!inode_is_locked(d_inode(dbuf->xadir)));
if (dbuf->count == ARRAY_SIZE(dbuf->dentries))
return -ENOSPC;
if (name[0] == '.' && (namelen < 2 ||
(namelen == 2 && name[1] == '.')))
return 0;
dentry = lookup_one_len(name, dbuf->xadir, namelen);
if (IS_ERR(dentry)) {
return PTR_ERR(dentry);
} else if (d_really_is_negative(dentry)) {
/* A directory entry exists, but no file? */
reiserfs_error(dentry->d_sb, "xattr-20003",
"Corrupted directory: xattr %pd listed but "
"not found for file %pd.\n",
dentry, dbuf->xadir);
dput(dentry);
return -EIO;
}
dbuf->dentries[dbuf->count++] = dentry;
return 0;
}
static void
cleanup_dentry_buf(struct reiserfs_dentry_buf *buf)
{
int i;
for (i = 0; i < buf->count; i++)
if (buf->dentries[i])
dput(buf->dentries[i]);
}
static int reiserfs_for_each_xattr(struct inode *inode,
int (*action)(struct dentry *, void *),
void *data)
{
struct dentry *dir;
int i, err = 0;
struct reiserfs_dentry_buf buf = {
.ctx.actor = fill_with_dentries,
};
/* Skip out, an xattr has no xattrs associated with it */
if (IS_PRIVATE(inode) || get_inode_sd_version(inode) == STAT_DATA_V1)
return 0;
dir = open_xa_dir(inode, XATTR_REPLACE);
if (IS_ERR(dir)) {
err = PTR_ERR(dir);
goto out;
} else if (d_really_is_negative(dir)) {
err = 0;
goto out_dir;
}
inode_lock_nested(d_inode(dir), I_MUTEX_XATTR);
buf.xadir = dir;
while (1) {
err = reiserfs_readdir_inode(d_inode(dir), &buf.ctx);
if (err)
break;
if (!buf.count)
break;
for (i = 0; !err && i < buf.count && buf.dentries[i]; i++) {
struct dentry *dentry = buf.dentries[i];
if (!d_is_dir(dentry))
err = action(dentry, data);
dput(dentry);
buf.dentries[i] = NULL;
}
if (err)
break;
buf.count = 0;
}
inode_unlock(d_inode(dir));
cleanup_dentry_buf(&buf);
if (!err) {
/*
* We start a transaction here to avoid a ABBA situation
* between the xattr root's i_mutex and the journal lock.
* This doesn't incur much additional overhead since the
* new transaction will just nest inside the
* outer transaction.
*/
int blocks = JOURNAL_PER_BALANCE_CNT * 2 + 2 +
4 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb);
struct reiserfs_transaction_handle th;
reiserfs_write_lock(inode->i_sb);
err = journal_begin(&th, inode->i_sb, blocks);
reiserfs_write_unlock(inode->i_sb);
if (!err) {
int jerror;
inode_lock_nested(d_inode(dir->d_parent),
I_MUTEX_XATTR);
err = action(dir, data);
reiserfs_write_lock(inode->i_sb);
jerror = journal_end(&th);
reiserfs_write_unlock(inode->i_sb);
inode_unlock(d_inode(dir->d_parent));
err = jerror ?: err;
}
}
out_dir:
dput(dir);
out:
/* -ENODATA isn't an error */
if (err == -ENODATA)
err = 0;
return err;
}
static int delete_one_xattr(struct dentry *dentry, void *data)
{
struct inode *dir = d_inode(dentry->d_parent);
/* This is the xattr dir, handle specially. */
if (d_is_dir(dentry))
return xattr_rmdir(dir, dentry);
return xattr_unlink(dir, dentry);
}
static int chown_one_xattr(struct dentry *dentry, void *data)
{
struct iattr *attrs = data;
int ia_valid = attrs->ia_valid;
int err;
/*
* We only want the ownership bits. Otherwise, we'll do
* things like change a directory to a regular file if
* ATTR_MODE is set.
*/
attrs->ia_valid &= (ATTR_UID|ATTR_GID);
err = reiserfs_setattr(dentry, attrs);
attrs->ia_valid = ia_valid;
return err;
}
/* No i_mutex, but the inode is unconnected. */
int reiserfs_delete_xattrs(struct inode *inode)
{
int err = reiserfs_for_each_xattr(inode, delete_one_xattr, NULL);
if (err)
reiserfs_warning(inode->i_sb, "jdm-20004",
"Couldn't delete all xattrs (%d)\n", err);
return err;
}
/* inode->i_mutex: down */
int reiserfs_chown_xattrs(struct inode *inode, struct iattr *attrs)
{
int err = reiserfs_for_each_xattr(inode, chown_one_xattr, attrs);
if (err)
reiserfs_warning(inode->i_sb, "jdm-20007",
"Couldn't chown all xattrs (%d)\n", err);
return err;
}
#ifdef CONFIG_REISERFS_FS_XATTR
/*
* Returns a dentry corresponding to a specific extended attribute file
* for the inode. If flags allow, the file is created. Otherwise, a
* valid or negative dentry, or an error is returned.
*/
static struct dentry *xattr_lookup(struct inode *inode, const char *name,
int flags)
{
struct dentry *xadir, *xafile;
int err = 0;
xadir = open_xa_dir(inode, flags);
if (IS_ERR(xadir))
return ERR_CAST(xadir);
inode_lock_nested(d_inode(xadir), I_MUTEX_XATTR);
xafile = lookup_one_len(name, xadir, strlen(name));
if (IS_ERR(xafile)) {
err = PTR_ERR(xafile);
goto out;
}
if (d_really_is_positive(xafile) && (flags & XATTR_CREATE))
err = -EEXIST;
if (d_really_is_negative(xafile)) {
err = -ENODATA;
if (xattr_may_create(flags))
err = xattr_create(d_inode(xadir), xafile,
0700|S_IFREG);
}
if (err)
dput(xafile);
out:
inode_unlock(d_inode(xadir));
dput(xadir);
if (err)
return ERR_PTR(err);
return xafile;
}
/* Internal operations on file data */
static inline void reiserfs_put_page(struct page *page)
{
kunmap(page);
put_page(page);
}
static struct page *reiserfs_get_page(struct inode *dir, size_t n)
{
struct address_space *mapping = dir->i_mapping;
struct page *page;
/*
* We can deadlock if we try to free dentries,
* and an unlink/rmdir has just occurred - GFP_NOFS avoids this
*/
mapping_set_gfp_mask(mapping, GFP_NOFS);
page = read_mapping_page(mapping, n >> PAGE_SHIFT, NULL);
if (!IS_ERR(page)) {
kmap(page);
if (PageError(page))
goto fail;
}
return page;
fail:
reiserfs_put_page(page);
return ERR_PTR(-EIO);
}
static inline __u32 xattr_hash(const char *msg, int len)
{
return csum_partial(msg, len, 0);
}
int reiserfs_commit_write(struct file *f, struct page *page,
unsigned from, unsigned to);
static void update_ctime(struct inode *inode)
{
struct timespec now = current_time(inode);
if (inode_unhashed(inode) || !inode->i_nlink ||
timespec_equal(&inode->i_ctime, &now))
return;
inode->i_ctime = current_time(inode);
mark_inode_dirty(inode);
}
static int lookup_and_delete_xattr(struct inode *inode, const char *name)
{
int err = 0;
struct dentry *dentry, *xadir;
xadir = open_xa_dir(inode, XATTR_REPLACE);
if (IS_ERR(xadir))
return PTR_ERR(xadir);
inode_lock_nested(d_inode(xadir), I_MUTEX_XATTR);
dentry = lookup_one_len(name, xadir, strlen(name));
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out_dput;
}
if (d_really_is_positive(dentry)) {
err = xattr_unlink(d_inode(xadir), dentry);
update_ctime(inode);
}
dput(dentry);
out_dput:
inode_unlock(d_inode(xadir));
dput(xadir);
return err;
}
/* Generic extended attribute operations that can be used by xa plugins */
/*
* inode->i_mutex: down
*/
int
reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
struct inode *inode, const char *name,
const void *buffer, size_t buffer_size, int flags)
{
int err = 0;
struct dentry *dentry;
struct page *page;
char *data;
size_t file_pos = 0;
size_t buffer_pos = 0;
size_t new_size;
__u32 xahash = 0;
if (get_inode_sd_version(inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
if (!buffer) {
err = lookup_and_delete_xattr(inode, name);
return err;
}
dentry = xattr_lookup(inode, name, flags);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
down_write(&REISERFS_I(inode)->i_xattr_sem);
xahash = xattr_hash(buffer, buffer_size);
while (buffer_pos < buffer_size || buffer_pos == 0) {
size_t chunk;
size_t skip = 0;
size_t page_offset = (file_pos & (PAGE_SIZE - 1));
if (buffer_size - buffer_pos > PAGE_SIZE)
chunk = PAGE_SIZE;
else
chunk = buffer_size - buffer_pos;
page = reiserfs_get_page(d_inode(dentry), file_pos);
if (IS_ERR(page)) {
err = PTR_ERR(page);
goto out_unlock;
}
lock_page(page);
data = page_address(page);
if (file_pos == 0) {
struct reiserfs_xattr_header *rxh;
skip = file_pos = sizeof(struct reiserfs_xattr_header);
if (chunk + skip > PAGE_SIZE)
chunk = PAGE_SIZE - skip;
rxh = (struct reiserfs_xattr_header *)data;
rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
rxh->h_hash = cpu_to_le32(xahash);
}
reiserfs_write_lock(inode->i_sb);
err = __reiserfs_write_begin(page, page_offset, chunk + skip);
if (!err) {
if (buffer)
memcpy(data + skip, buffer + buffer_pos, chunk);
err = reiserfs_commit_write(NULL, page, page_offset,
page_offset + chunk +
skip);
}
reiserfs_write_unlock(inode->i_sb);
unlock_page(page);
reiserfs_put_page(page);
buffer_pos += chunk;
file_pos += chunk;
skip = 0;
if (err || buffer_size == 0 || !buffer)
break;
}
new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
if (!err && new_size < i_size_read(d_inode(dentry))) {
struct iattr newattrs = {
.ia_ctime = current_time(inode),
.ia_size = new_size,
.ia_valid = ATTR_SIZE | ATTR_CTIME,
};
inode_lock_nested(d_inode(dentry), I_MUTEX_XATTR);
inode_dio_wait(d_inode(dentry));
err = reiserfs_setattr(dentry, &newattrs);
inode_unlock(d_inode(dentry));
} else
update_ctime(inode);
out_unlock:
up_write(&REISERFS_I(inode)->i_xattr_sem);
dput(dentry);
return err;
}
/* We need to start a transaction to maintain lock ordering */
int reiserfs_xattr_set(struct inode *inode, const char *name,
const void *buffer, size_t buffer_size, int flags)
{
struct reiserfs_transaction_handle th;
int error, error2;
size_t jbegin_count = reiserfs_xattr_nblocks(inode, buffer_size);
if (!(flags & XATTR_REPLACE))
jbegin_count += reiserfs_xattr_jcreate_nblocks(inode);
reiserfs_write_lock(inode->i_sb);
error = journal_begin(&th, inode->i_sb, jbegin_count);
reiserfs_write_unlock(inode->i_sb);
if (error) {
return error;
}
error = reiserfs_xattr_set_handle(&th, inode, name,
buffer, buffer_size, flags);
reiserfs_write_lock(inode->i_sb);
error2 = journal_end(&th);
reiserfs_write_unlock(inode->i_sb);
if (error == 0)
error = error2;
return error;
}
/*
* inode->i_mutex: down
*/
int
reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
size_t buffer_size)
{
ssize_t err = 0;
struct dentry *dentry;
size_t isize;
size_t file_pos = 0;
size_t buffer_pos = 0;
struct page *page;
__u32 hash = 0;
if (name == NULL)
return -EINVAL;
/*
* We can't have xattrs attached to v1 items since they don't have
* generation numbers
*/
if (get_inode_sd_version(inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
dentry = xattr_lookup(inode, name, XATTR_REPLACE);
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out;
}
down_read(&REISERFS_I(inode)->i_xattr_sem);
isize = i_size_read(d_inode(dentry));
/* Just return the size needed */
if (buffer == NULL) {
err = isize - sizeof(struct reiserfs_xattr_header);
goto out_unlock;
}
if (buffer_size < isize - sizeof(struct reiserfs_xattr_header)) {
err = -ERANGE;
goto out_unlock;
}
while (file_pos < isize) {
size_t chunk;
char *data;
size_t skip = 0;
if (isize - file_pos > PAGE_SIZE)
chunk = PAGE_SIZE;
else
chunk = isize - file_pos;
page = reiserfs_get_page(d_inode(dentry), file_pos);
if (IS_ERR(page)) {
err = PTR_ERR(page);
goto out_unlock;
}
lock_page(page);
data = page_address(page);
if (file_pos == 0) {
struct reiserfs_xattr_header *rxh =
(struct reiserfs_xattr_header *)data;
skip = file_pos = sizeof(struct reiserfs_xattr_header);
chunk -= skip;
/* Magic doesn't match up.. */
if (rxh->h_magic != cpu_to_le32(REISERFS_XATTR_MAGIC)) {
unlock_page(page);
reiserfs_put_page(page);
reiserfs_warning(inode->i_sb, "jdm-20001",
"Invalid magic for xattr (%s) "
"associated with %k", name,
INODE_PKEY(inode));
err = -EIO;
goto out_unlock;
}
hash = le32_to_cpu(rxh->h_hash);
}
memcpy(buffer + buffer_pos, data + skip, chunk);
unlock_page(page);
reiserfs_put_page(page);
file_pos += chunk;
buffer_pos += chunk;
skip = 0;
}
err = isize - sizeof(struct reiserfs_xattr_header);
if (xattr_hash(buffer, isize - sizeof(struct reiserfs_xattr_header)) !=
hash) {
reiserfs_warning(inode->i_sb, "jdm-20002",
"Invalid hash for xattr (%s) associated "
"with %k", name, INODE_PKEY(inode));
err = -EIO;
}
out_unlock:
up_read(&REISERFS_I(inode)->i_xattr_sem);
dput(dentry);
out:
return err;
}
/*
* In order to implement different sets of xattr operations for each xattr
* prefix with the generic xattr API, a filesystem should create a
* null-terminated array of struct xattr_handler (one for each prefix) and
* hang a pointer to it off of the s_xattr field of the superblock.
*
* The generic_fooxattr() functions will use this list to dispatch xattr
* operations to the correct xattr_handler.
*/
#define for_each_xattr_handler(handlers, handler) \
for ((handler) = *(handlers)++; \
(handler) != NULL; \
(handler) = *(handlers)++)
/* This is the implementation for the xattr plugin infrastructure */
static inline const struct xattr_handler *
find_xattr_handler_prefix(const struct xattr_handler **handlers,
const char *name)
{
const struct xattr_handler *xah;
if (!handlers)
return NULL;
for_each_xattr_handler(handlers, xah) {
const char *prefix = xattr_prefix(xah);
if (strncmp(prefix, name, strlen(prefix)) == 0)
break;
}
return xah;
}
struct listxattr_buf {
struct dir_context ctx;
size_t size;
size_t pos;
char *buf;
struct dentry *dentry;
};
static int listxattr_filler(struct dir_context *ctx, const char *name,
int namelen, loff_t offset, u64 ino,
unsigned int d_type)
{
struct listxattr_buf *b =
container_of(ctx, struct listxattr_buf, ctx);
size_t size;
if (name[0] != '.' ||
(namelen != 1 && (name[1] != '.' || namelen != 2))) {
const struct xattr_handler *handler;
handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
name);
if (!handler /* Unsupported xattr name */ ||
(handler->list && !handler->list(b->dentry)))
return 0;
size = namelen + 1;
if (b->buf) {
if (size > b->size)
return -ERANGE;
memcpy(b->buf + b->pos, name, namelen);
b->buf[b->pos + namelen] = 0;
}
b->pos += size;
}
return 0;
}
/*
* Inode operation listxattr()
*
* We totally ignore the generic listxattr here because it would be stupid
* not to. Since the xattrs are organized in a directory, we can just
* readdir to find them.
*/
ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
{
struct dentry *dir;
int err = 0;
struct listxattr_buf buf = {
.ctx.actor = listxattr_filler,
.dentry = dentry,
.buf = buffer,
.size = buffer ? size : 0,
};
if (d_really_is_negative(dentry))
return -EINVAL;
if (!dentry->d_sb->s_xattr ||
get_inode_sd_version(d_inode(dentry)) == STAT_DATA_V1)
return -EOPNOTSUPP;
dir = open_xa_dir(d_inode(dentry), XATTR_REPLACE);
if (IS_ERR(dir)) {
err = PTR_ERR(dir);
if (err == -ENODATA)
err = 0; /* Not an error if there aren't any xattrs */
goto out;
}
inode_lock_nested(d_inode(dir), I_MUTEX_XATTR);
err = reiserfs_readdir_inode(d_inode(dir), &buf.ctx);
inode_unlock(d_inode(dir));
if (!err)
err = buf.pos;
dput(dir);
out:
return err;
}
static int create_privroot(struct dentry *dentry)
{
int err;
struct inode *inode = d_inode(dentry->d_parent);
WARN_ON_ONCE(!inode_is_locked(inode));
err = xattr_mkdir(inode, dentry, 0700);
if (err || d_really_is_negative(dentry)) {
reiserfs_warning(dentry->d_sb, "jdm-20006",
"xattrs/ACLs enabled and couldn't "
"find/create .reiserfs_priv. "
"Failing mount.");
return -EOPNOTSUPP;
}
d_inode(dentry)->i_flags |= S_PRIVATE;
reiserfs_info(dentry->d_sb, "Created %s - reserved for xattr "
"storage.\n", PRIVROOT_NAME);
return 0;
}
#else
int __init reiserfs_xattr_register_handlers(void) { return 0; }
void reiserfs_xattr_unregister_handlers(void) {}
static int create_privroot(struct dentry *dentry) { return 0; }
#endif
/* Actual operations that are exported to VFS-land */
static const struct xattr_handler *reiserfs_xattr_handlers[] = {
#ifdef CONFIG_REISERFS_FS_XATTR
&reiserfs_xattr_user_handler,
&reiserfs_xattr_trusted_handler,
#endif
#ifdef CONFIG_REISERFS_FS_SECURITY
&reiserfs_xattr_security_handler,
#endif
#ifdef CONFIG_REISERFS_FS_POSIX_ACL
&posix_acl_access_xattr_handler,
&posix_acl_default_xattr_handler,
#endif
NULL
};
static int xattr_mount_check(struct super_block *s)
{
/*
* We need generation numbers to ensure that the oid mapping is correct
* v3.5 filesystems don't have them.
*/
if (old_format_only(s)) {
if (reiserfs_xattrs_optional(s)) {
/*
* Old format filesystem, but optional xattrs have
* been enabled. Error out.
*/
reiserfs_warning(s, "jdm-2005",
"xattrs/ACLs not supported "
"on pre-v3.6 format filesystems. "
"Failing mount.");
return -EOPNOTSUPP;
}
}
return 0;
}
int reiserfs_permission(struct inode *inode, int mask)
{
/*
* We don't do permission checks on the internal objects.
* Permissions are determined by the "owning" object.
*/
if (IS_PRIVATE(inode))
return 0;
return generic_permission(inode, mask);
}
static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
{
return -EPERM;
}
static const struct dentry_operations xattr_lookup_poison_ops = {
.d_revalidate = xattr_hide_revalidate,
};
int reiserfs_lookup_privroot(struct super_block *s)
{
struct dentry *dentry;
int err = 0;
/* If we don't have the privroot located yet - go find it */
inode_lock(d_inode(s->s_root));
dentry = lookup_one_len(PRIVROOT_NAME, s->s_root,
strlen(PRIVROOT_NAME));
if (!IS_ERR(dentry)) {
REISERFS_SB(s)->priv_root = dentry;
d_set_d_op(dentry, &xattr_lookup_poison_ops);
if (d_really_is_positive(dentry))
d_inode(dentry)->i_flags |= S_PRIVATE;
} else
err = PTR_ERR(dentry);
inode_unlock(d_inode(s->s_root));
return err;
}
/*
* We need to take a copy of the mount flags since things like
* MS_RDONLY don't get set until *after* we're called.
* mount_flags != mount_options
*/
int reiserfs_xattr_init(struct super_block *s, int mount_flags)
{
int err = 0;
struct dentry *privroot = REISERFS_SB(s)->priv_root;
err = xattr_mount_check(s);
if (err)
goto error;
if (d_really_is_negative(privroot) && !(mount_flags & MS_RDONLY)) {
inode_lock(d_inode(s->s_root));
err = create_privroot(REISERFS_SB(s)->priv_root);
inode_unlock(d_inode(s->s_root));
}
if (d_really_is_positive(privroot)) {
s->s_xattr = reiserfs_xattr_handlers;
inode_lock(d_inode(privroot));
if (!REISERFS_SB(s)->xattr_root) {
struct dentry *dentry;
dentry = lookup_one_len(XAROOT_NAME, privroot,
strlen(XAROOT_NAME));
if (!IS_ERR(dentry))
REISERFS_SB(s)->xattr_root = dentry;
else
err = PTR_ERR(dentry);
}
inode_unlock(d_inode(privroot));
}
error:
if (err) {
clear_bit(REISERFS_XATTRS_USER, &REISERFS_SB(s)->s_mount_opt);
clear_bit(REISERFS_POSIXACL, &REISERFS_SB(s)->s_mount_opt);
}
/* The super_block MS_POSIXACL must mirror the (no)acl mount option. */
if (reiserfs_posixacl(s))
s->s_flags |= MS_POSIXACL;
else
s->s_flags &= ~MS_POSIXACL;
return err;
}