1 /* Update program header program header table entry.
2 Copyright (C) 2000-2010 Red Hat, Inc.
3 This file is part of elfutils.
4 Written by Ulrich Drepper <drepper@redhat.com>, 2000.
5
6 This file is free software; you can redistribute it and/or modify
7 it under the terms of either
8
9 * the GNU Lesser General Public License as published by the Free
10 Software Foundation; either version 3 of the License, or (at
11 your option) any later version
12
13 or
14
15 * the GNU General Public License as published by the Free
16 Software Foundation; either version 2 of the License, or (at
17 your option) any later version
18
19 or both in parallel, as here.
20
21 elfutils is distributed in the hope that it will be useful, but
22 WITHOUT ANY WARRANTY; without even the implied warranty of
23 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
24 General Public License for more details.
25
26 You should have received copies of the GNU General Public License and
27 the GNU Lesser General Public License along with this program. If
28 not, see <http://www.gnu.org/licenses/>. */
29
30 #ifdef HAVE_CONFIG_H
31 # include <config.h>
32 #endif
33
34 #include <gelf.h>
35 #include <string.h>
36
37 #include "libelfP.h"
38
39
40 int
gelf_update_phdr(Elf * elf,int ndx,GElf_Phdr * src)41 gelf_update_phdr (Elf *elf, int ndx, GElf_Phdr *src)
42 {
43 int result = 0;
44
45 if (elf == NULL)
46 return 0;
47
48 if (unlikely (elf->kind != ELF_K_ELF))
49 {
50 __libelf_seterrno (ELF_E_INVALID_HANDLE);
51 return 0;
52 }
53
54 rwlock_wrlock (elf->lock);
55
56 if (elf->class == ELFCLASS32)
57 {
58 Elf32_Phdr *phdr = elf->state.elf32.phdr;
59
60 /* We have to convert the data to the 32 bit format. This might
61 overflow some fields so we have to test for this case before
62 copying. */
63 if (unlikely (src->p_offset > 0xffffffffull)
64 || unlikely (src->p_vaddr > 0xffffffffull)
65 || unlikely (src->p_paddr > 0xffffffffull)
66 || unlikely (src->p_filesz > 0xffffffffull)
67 || unlikely (src->p_memsz > 0xffffffffull)
68 || unlikely (src->p_align > 0xffffffffull))
69 {
70 __libelf_seterrno (ELF_E_INVALID_DATA);
71 goto out;
72 }
73
74 if (phdr == NULL)
75 {
76 phdr = __elf32_getphdr_wrlock (elf);
77 if (phdr == NULL)
78 /* The error number is already set. */
79 goto out;
80 }
81
82 /* Test whether the index is ok. */
83 size_t phnum;
84 if (ndx >= elf->state.elf32.ehdr->e_phnum
85 && (elf->state.elf32.ehdr->e_phnum != PN_XNUM
86 || __elf_getphdrnum_rdlock (elf, &phnum) != 0
87 || (size_t) ndx >= phnum))
88 {
89 __libelf_seterrno (ELF_E_INVALID_INDEX);
90 goto out;
91 }
92
93 /* Now correct the pointer to point to the correct element. */
94 phdr += ndx;
95
96 #define COPY(name) \
97 phdr->name = src->name
98 COPY (p_type);
99 COPY (p_offset);
100 COPY (p_vaddr);
101 COPY (p_paddr);
102 COPY (p_filesz);
103 COPY (p_memsz);
104 COPY (p_flags);
105 COPY (p_align);
106 }
107 else
108 {
109 Elf64_Phdr *phdr = elf->state.elf64.phdr;
110
111 if (phdr == NULL)
112 {
113 phdr = __elf64_getphdr_wrlock (elf);
114 if (phdr == NULL)
115 /* The error number is already set. */
116 goto out;
117 }
118
119 /* Test whether the index is ok. */
120 size_t phnum;
121 if (ndx >= elf->state.elf64.ehdr->e_phnum
122 && (elf->state.elf64.ehdr->e_phnum != PN_XNUM
123 || __elf_getphdrnum_rdlock (elf, &phnum) != 0
124 || (size_t) ndx >= phnum))
125 {
126 __libelf_seterrno (ELF_E_INVALID_INDEX);
127 goto out;
128 }
129
130 /* Just copy the data. */
131 memcpy (phdr + ndx, src, sizeof (Elf64_Phdr));
132 }
133
134 /* Mark the program header as modified. */
135 elf->state.elf.phdr_flags |= ELF_F_DIRTY;
136
137 result = 1;
138
139 out:
140 rwlock_unlock (elf->lock);
141
142 return result;
143 }
144