120 lines
2.8 KiB
C
120 lines
2.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* linux/fs/ext4/symlink.c
|
|
*
|
|
* Only fast symlinks left here - the rest is done by generic code. AV, 1999
|
|
*
|
|
* Copyright (C) 1992, 1993, 1994, 1995
|
|
* Remy Card (card@masi.ibp.fr)
|
|
* Laboratoire MASI - Institut Blaise Pascal
|
|
* Universite Pierre et Marie Curie (Paris VI)
|
|
*
|
|
* from
|
|
*
|
|
* linux/fs/minix/symlink.c
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
*
|
|
* ext4 symlink handling code
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/namei.h>
|
|
#include "ext4.h"
|
|
#include "xattr.h"
|
|
|
|
static const char *ext4_encrypted_get_link(struct dentry *dentry,
|
|
struct inode *inode,
|
|
struct delayed_call *done)
|
|
{
|
|
struct buffer_head *bh = NULL;
|
|
const void *caddr;
|
|
unsigned int max_size;
|
|
const char *paddr;
|
|
|
|
if (!dentry)
|
|
return ERR_PTR(-ECHILD);
|
|
|
|
if (ext4_inode_is_fast_symlink(inode)) {
|
|
caddr = EXT4_I(inode)->i_data;
|
|
max_size = sizeof(EXT4_I(inode)->i_data);
|
|
} else {
|
|
bh = ext4_bread(NULL, inode, 0, 0);
|
|
if (IS_ERR(bh))
|
|
return ERR_CAST(bh);
|
|
if (!bh) {
|
|
EXT4_ERROR_INODE(inode, "bad symlink.");
|
|
return ERR_PTR(-EFSCORRUPTED);
|
|
}
|
|
caddr = bh->b_data;
|
|
max_size = inode->i_sb->s_blocksize;
|
|
}
|
|
|
|
paddr = fscrypt_get_symlink(inode, caddr, max_size, done);
|
|
brelse(bh);
|
|
return paddr;
|
|
}
|
|
|
|
static int ext4_encrypted_symlink_getattr(struct user_namespace *mnt_userns,
|
|
const struct path *path,
|
|
struct kstat *stat, u32 request_mask,
|
|
unsigned int query_flags)
|
|
{
|
|
ext4_getattr(mnt_userns, path, stat, request_mask, query_flags);
|
|
|
|
return fscrypt_symlink_getattr(path, stat);
|
|
}
|
|
|
|
static void ext4_free_link(void *bh)
|
|
{
|
|
brelse(bh);
|
|
}
|
|
|
|
static const char *ext4_get_link(struct dentry *dentry, struct inode *inode,
|
|
struct delayed_call *callback)
|
|
{
|
|
struct buffer_head *bh;
|
|
|
|
if (!dentry) {
|
|
bh = ext4_getblk(NULL, inode, 0, EXT4_GET_BLOCKS_CACHED_NOWAIT);
|
|
if (IS_ERR(bh))
|
|
return ERR_CAST(bh);
|
|
if (!bh || !ext4_buffer_uptodate(bh))
|
|
return ERR_PTR(-ECHILD);
|
|
} else {
|
|
bh = ext4_bread(NULL, inode, 0, 0);
|
|
if (IS_ERR(bh))
|
|
return ERR_CAST(bh);
|
|
if (!bh) {
|
|
EXT4_ERROR_INODE(inode, "bad symlink.");
|
|
return ERR_PTR(-EFSCORRUPTED);
|
|
}
|
|
}
|
|
|
|
set_delayed_call(callback, ext4_free_link, bh);
|
|
nd_terminate_link(bh->b_data, inode->i_size,
|
|
inode->i_sb->s_blocksize - 1);
|
|
return bh->b_data;
|
|
}
|
|
|
|
const struct inode_operations ext4_encrypted_symlink_inode_operations = {
|
|
.get_link = ext4_encrypted_get_link,
|
|
.setattr = ext4_setattr,
|
|
.getattr = ext4_encrypted_symlink_getattr,
|
|
.listxattr = ext4_listxattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_symlink_inode_operations = {
|
|
.get_link = ext4_get_link,
|
|
.setattr = ext4_setattr,
|
|
.getattr = ext4_getattr,
|
|
.listxattr = ext4_listxattr,
|
|
};
|
|
|
|
const struct inode_operations ext4_fast_symlink_inode_operations = {
|
|
.get_link = simple_get_link,
|
|
.setattr = ext4_setattr,
|
|
.getattr = ext4_getattr,
|
|
.listxattr = ext4_listxattr,
|
|
};
|