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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
|
/* Get ELF program header table.
Copyright (C) 1998-2010, 2014 Red Hat, Inc.
This file is part of elfutils.
Written by Ulrich Drepper <drepper@redhat.com>, 1998.
This file is free software; you can redistribute it and/or modify
it under the terms of either
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at
your option) any later version
or
* the GNU General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at
your option) any later version
or both in parallel, as here.
elfutils is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received copies of the GNU General Public License and
the GNU Lesser General Public License along with this program. If
not, see <http://www.gnu.org/licenses/>. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <errno.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <assert.h>
#include <system.h>
#include "libelfP.h"
#include "common.h"
#ifndef LIBELFBITS
# define LIBELFBITS 32
#endif
ElfW2(LIBELFBITS,Phdr) *
__elfw2(LIBELFBITS,getphdr_wrlock) (elf)
Elf *elf;
{
ElfW2(LIBELFBITS,Phdr) *result;
/* If the program header entry has already been filled in the code
below must already have been run. So the class is set, too. No
need to waste any more time here. */
result = elf->state.ELFW(elf,LIBELFBITS).phdr;
if (likely (result != NULL))
return result;
if (elf->class == 0)
elf->class = ELFW(ELFCLASS,LIBELFBITS);
else if (elf->class != ELFW(ELFCLASS,LIBELFBITS))
{
__libelf_seterrno (ELF_E_INVALID_CLASS);
result = NULL;
goto out;
}
if (likely (result == NULL))
{
/* Read the section header table. */
ElfW2(LIBELFBITS,Ehdr) *ehdr = elf->state.ELFW(elf,LIBELFBITS).ehdr;
/* If no program header exists return NULL. */
size_t phnum;
if (__elf_getphdrnum_rdlock (elf, &phnum) != 0)
goto out;
if (phnum == 0 || ehdr->e_phoff == 0)
{
__libelf_seterrno (ELF_E_NO_PHDR);
goto out;
}
/* Check this doesn't overflow. */
size_t size = phnum * sizeof (ElfW2(LIBELFBITS,Phdr));
if (phnum > SIZE_MAX / sizeof (ElfW2(LIBELFBITS,Phdr))
|| ehdr->e_phoff > elf->maximum_size
|| elf->maximum_size - ehdr->e_phoff < size)
{
__libelf_seterrno (ELF_E_INVALID_DATA);
goto out;
}
if (elf->map_address != NULL)
{
/* First see whether the information in the ELF header is
valid and it does not ask for too much. */
if (unlikely (ehdr->e_phoff >= elf->maximum_size)
|| unlikely (elf->maximum_size - ehdr->e_phoff < size))
{
/* Something is wrong. */
__libelf_seterrno (ELF_E_INVALID_PHDR);
goto out;
}
/* All the data is already mapped. Use it. */
void *file_phdr = ((char *) elf->map_address
+ elf->start_offset + ehdr->e_phoff);
if (ehdr->e_ident[EI_DATA] == MY_ELFDATA
&& (ALLOW_UNALIGNED
|| ((uintptr_t) file_phdr
& (__alignof__ (ElfW2(LIBELFBITS,Phdr)) - 1)) == 0))
/* Simply use the mapped data. */
elf->state.ELFW(elf,LIBELFBITS).phdr = file_phdr;
else
{
ElfW2(LIBELFBITS,Phdr) *notcvt;
ElfW2(LIBELFBITS,Phdr) *phdr;
/* Allocate memory for the program headers. We know the number
of entries from the ELF header. */
phdr = elf->state.ELFW(elf,LIBELFBITS).phdr =
(ElfW2(LIBELFBITS,Phdr) *) malloc (size);
if (elf->state.ELFW(elf,LIBELFBITS).phdr == NULL)
{
__libelf_seterrno (ELF_E_NOMEM);
goto out;
}
elf->state.ELFW(elf,LIBELFBITS).phdr_flags |=
ELF_F_MALLOCED | ELF_F_DIRTY;
/* Now copy the data and at the same time convert the
byte order. */
if (ehdr->e_ident[EI_DATA] == MY_ELFDATA)
{
assert (! ALLOW_UNALIGNED);
memcpy (phdr, file_phdr, size);
}
else
{
if (ALLOW_UNALIGNED
|| ((uintptr_t) file_phdr
& (__alignof__ (ElfW2(LIBELFBITS,Phdr)) - 1)) == 0)
notcvt = file_phdr;
else
{
notcvt = (ElfW2(LIBELFBITS,Phdr) *) alloca (size);
memcpy (notcvt, file_phdr, size);
}
for (size_t cnt = 0; cnt < phnum; ++cnt)
{
CONVERT_TO (phdr[cnt].p_type, notcvt[cnt].p_type);
CONVERT_TO (phdr[cnt].p_offset, notcvt[cnt].p_offset);
CONVERT_TO (phdr[cnt].p_vaddr, notcvt[cnt].p_vaddr);
CONVERT_TO (phdr[cnt].p_paddr, notcvt[cnt].p_paddr);
CONVERT_TO (phdr[cnt].p_filesz, notcvt[cnt].p_filesz);
CONVERT_TO (phdr[cnt].p_memsz, notcvt[cnt].p_memsz);
CONVERT_TO (phdr[cnt].p_flags, notcvt[cnt].p_flags);
CONVERT_TO (phdr[cnt].p_align, notcvt[cnt].p_align);
}
}
}
}
else if (likely (elf->fildes != -1))
{
/* Allocate memory for the program headers. We know the number
of entries from the ELF header. */
elf->state.ELFW(elf,LIBELFBITS).phdr =
(ElfW2(LIBELFBITS,Phdr) *) malloc (size);
if (elf->state.ELFW(elf,LIBELFBITS).phdr == NULL)
{
__libelf_seterrno (ELF_E_NOMEM);
goto out;
}
elf->state.ELFW(elf,LIBELFBITS).phdr_flags |= ELF_F_MALLOCED;
/* Read the header. */
ssize_t n = pread_retry (elf->fildes,
elf->state.ELFW(elf,LIBELFBITS).phdr, size,
elf->start_offset + ehdr->e_phoff);
if (unlikely ((size_t) n != size))
{
/* Severe problems. We cannot read the data. */
__libelf_seterrno (ELF_E_READ_ERROR);
free (elf->state.ELFW(elf,LIBELFBITS).phdr);
elf->state.ELFW(elf,LIBELFBITS).phdr = NULL;
goto out;
}
/* If the byte order of the file is not the same as the one
of the host convert the data now. */
if (ehdr->e_ident[EI_DATA] != MY_ELFDATA)
{
ElfW2(LIBELFBITS,Phdr) *phdr
= elf->state.ELFW(elf,LIBELFBITS).phdr;
for (size_t cnt = 0; cnt < phnum; ++cnt)
{
CONVERT (phdr[cnt].p_type);
CONVERT (phdr[cnt].p_offset);
CONVERT (phdr[cnt].p_vaddr);
CONVERT (phdr[cnt].p_paddr);
CONVERT (phdr[cnt].p_filesz);
CONVERT (phdr[cnt].p_memsz);
CONVERT (phdr[cnt].p_flags);
CONVERT (phdr[cnt].p_align);
}
}
}
else
{
/* The file descriptor was already enabled and not all data was
read. */
__libelf_seterrno (ELF_E_FD_DISABLED);
goto out;
}
result = elf->state.ELFW(elf,LIBELFBITS).phdr;
}
out:
return result;
}
ElfW2(LIBELFBITS,Phdr) *
elfw2(LIBELFBITS,getphdr) (elf)
Elf *elf;
{
ElfW2(LIBELFBITS,Phdr) *result;
if (elf == NULL)
return NULL;
if (unlikely (elf->kind != ELF_K_ELF))
{
__libelf_seterrno (ELF_E_INVALID_HANDLE);
return NULL;
}
/* If the program header entry has already been filled in the code
* in getphdr_wrlock must already have been run. So the class is
* set, too. No need to waste any more time here. */
result = elf->state.ELFW(elf,LIBELFBITS).phdr;
if (likely (result != NULL))
return result;
rwlock_wrlock (elf->lock);
result = __elfw2(LIBELFBITS,getphdr_wrlock) (elf);
rwlock_unlock (elf->lock);
return result;
}
INTDEF(elfw2(LIBELFBITS,getphdr))
|
