linux_dsm_epyc7002/fs/reiserfs/xattr_security.c
Jeff Mahoney 57fe60df62 reiserfs: add atomic addition of selinux attributes during inode creation
Some time ago, some changes were made to make security inode attributes
be atomically written during inode creation.  ReiserFS fell behind in
this area, but with the reworking of the xattr code, it's now fairly
easy to add.

The following patch adds the ability for security attributes to be added
automatically during inode creation.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-30 12:16:39 -07:00

110 lines
2.6 KiB
C

#include <linux/reiserfs_fs.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include <linux/reiserfs_xattr.h>
#include <linux/security.h>
#include <asm/uaccess.h>
static int
security_get(struct inode *inode, const char *name, void *buffer, size_t size)
{
if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
if (IS_PRIVATE(inode))
return -EPERM;
return reiserfs_xattr_get(inode, name, buffer, size);
}
static int
security_set(struct inode *inode, const char *name, const void *buffer,
size_t size, int flags)
{
if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
if (IS_PRIVATE(inode))
return -EPERM;
return reiserfs_xattr_set(inode, name, buffer, size, flags);
}
static size_t security_list(struct inode *inode, char *list, size_t list_len,
const char *name, size_t namelen)
{
const size_t len = namelen + 1;
if (IS_PRIVATE(inode))
return 0;
if (list && len <= list_len) {
memcpy(list, name, namelen);
list[namelen] = '\0';
}
return len;
}
/* Initializes the security context for a new inode and returns the number
* of blocks needed for the transaction. If successful, reiserfs_security
* must be released using reiserfs_security_free when the caller is done. */
int reiserfs_security_init(struct inode *dir, struct inode *inode,
struct reiserfs_security_handle *sec)
{
int blocks = 0;
int error = security_inode_init_security(inode, dir, &sec->name,
&sec->value, &sec->length);
if (error) {
if (error == -EOPNOTSUPP)
error = 0;
sec->name = NULL;
sec->value = NULL;
sec->length = 0;
return error;
}
if (sec->length) {
blocks = reiserfs_xattr_jcreate_nblocks(inode) +
reiserfs_xattr_nblocks(inode, sec->length);
/* We don't want to count the directories twice if we have
* a default ACL. */
REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
}
return blocks;
}
int reiserfs_security_write(struct reiserfs_transaction_handle *th,
struct inode *inode,
struct reiserfs_security_handle *sec)
{
int error;
if (strlen(sec->name) < sizeof(XATTR_SECURITY_PREFIX))
return -EINVAL;
error = reiserfs_xattr_set_handle(th, inode, sec->name, sec->value,
sec->length, XATTR_CREATE);
if (error == -ENODATA || error == -EOPNOTSUPP)
error = 0;
return error;
}
void reiserfs_security_free(struct reiserfs_security_handle *sec)
{
kfree(sec->name);
kfree(sec->value);
sec->name = NULL;
sec->value = NULL;
}
struct xattr_handler reiserfs_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.get = security_get,
.set = security_set,
.list = security_list,
};