1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
// 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;
char *inline_link;
/*
* Create a new inlined symlink is not supported, just provide a
* method to read the leftovers.
*/
if (ext4_has_inline_data(inode)) {
if (!dentry)
return ERR_PTR(-ECHILD);
inline_link = ext4_read_inline_link(inode);
if (!IS_ERR(inline_link))
set_delayed_call(callback, kfree_link, inline_link);
return inline_link;
}
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,
};
|
