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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
*/
#include <unistd.h>
#include <asm/orc_types.h>
#include <objtool/objtool.h>
#include <objtool/warn.h>
#include <objtool/endianness.h>
static const char *reg_name(unsigned int reg)
{
switch (reg) {
case ORC_REG_PREV_SP:
return "prevsp";
case ORC_REG_DX:
return "dx";
case ORC_REG_DI:
return "di";
case ORC_REG_BP:
return "bp";
case ORC_REG_SP:
return "sp";
case ORC_REG_R10:
return "r10";
case ORC_REG_R13:
return "r13";
case ORC_REG_BP_INDIRECT:
return "bp(ind)";
case ORC_REG_SP_INDIRECT:
return "sp(ind)";
default:
return "?";
}
}
static const char *orc_type_name(unsigned int type)
{
switch (type) {
case ORC_TYPE_UNDEFINED:
return "(und)";
case ORC_TYPE_END_OF_STACK:
return "end";
case ORC_TYPE_CALL:
return "call";
case ORC_TYPE_REGS:
return "regs";
case ORC_TYPE_REGS_PARTIAL:
return "regs (partial)";
default:
return "?";
}
}
static void print_reg(unsigned int reg, int offset)
{
if (reg == ORC_REG_BP_INDIRECT)
printf("(bp%+d)", offset);
else if (reg == ORC_REG_SP_INDIRECT)
printf("(sp)%+d", offset);
else if (reg == ORC_REG_UNDEFINED)
printf("(und)");
else
printf("%s%+d", reg_name(reg), offset);
}
int orc_dump(const char *_objname)
{
int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0;
struct orc_entry *orc = NULL;
char *name;
size_t nr_sections;
Elf64_Addr orc_ip_addr = 0;
size_t shstrtab_idx, strtab_idx = 0;
Elf *elf;
Elf_Scn *scn;
GElf_Shdr sh;
GElf_Rela rela;
GElf_Sym sym;
Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
struct elf dummy_elf = {};
objname = _objname;
elf_version(EV_CURRENT);
fd = open(objname, O_RDONLY);
if (fd == -1) {
perror("open");
return -1;
}
elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
if (!elf) {
WARN_ELF("elf_begin");
return -1;
}
if (!elf64_getehdr(elf)) {
WARN_ELF("elf64_getehdr");
return -1;
}
memcpy(&dummy_elf.ehdr, elf64_getehdr(elf), sizeof(dummy_elf.ehdr));
if (elf_getshdrnum(elf, &nr_sections)) {
WARN_ELF("elf_getshdrnum");
return -1;
}
if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
WARN_ELF("elf_getshdrstrndx");
return -1;
}
for (i = 0; i < nr_sections; i++) {
scn = elf_getscn(elf, i);
if (!scn) {
WARN_ELF("elf_getscn");
return -1;
}
if (!gelf_getshdr(scn, &sh)) {
WARN_ELF("gelf_getshdr");
return -1;
}
name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
if (!name) {
WARN_ELF("elf_strptr");
return -1;
}
data = elf_getdata(scn, NULL);
if (!data) {
WARN_ELF("elf_getdata");
return -1;
}
if (!strcmp(name, ".symtab")) {
symtab = data;
} else if (!strcmp(name, ".strtab")) {
strtab_idx = i;
} else if (!strcmp(name, ".orc_unwind")) {
orc = data->d_buf;
orc_size = sh.sh_size;
} else if (!strcmp(name, ".orc_unwind_ip")) {
orc_ip = data->d_buf;
orc_ip_addr = sh.sh_addr;
} else if (!strcmp(name, ".rela.orc_unwind_ip")) {
rela_orc_ip = data;
}
}
if (!symtab || !strtab_idx || !orc || !orc_ip)
return 0;
if (orc_size % sizeof(*orc) != 0) {
WARN("bad .orc_unwind section size");
return -1;
}
nr_entries = orc_size / sizeof(*orc);
for (i = 0; i < nr_entries; i++) {
if (rela_orc_ip) {
if (!gelf_getrela(rela_orc_ip, i, &rela)) {
WARN_ELF("gelf_getrela");
return -1;
}
if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
WARN_ELF("gelf_getsym");
return -1;
}
if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
scn = elf_getscn(elf, sym.st_shndx);
if (!scn) {
WARN_ELF("elf_getscn");
return -1;
}
if (!gelf_getshdr(scn, &sh)) {
WARN_ELF("gelf_getshdr");
return -1;
}
name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
if (!name) {
WARN_ELF("elf_strptr");
return -1;
}
} else {
name = elf_strptr(elf, strtab_idx, sym.st_name);
if (!name) {
WARN_ELF("elf_strptr");
return -1;
}
}
printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
} else {
printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
}
printf("type:%s", orc_type_name(orc[i].type));
printf(" sp:");
print_reg(orc[i].sp_reg, bswap_if_needed(&dummy_elf, orc[i].sp_offset));
printf(" bp:");
print_reg(orc[i].bp_reg, bswap_if_needed(&dummy_elf, orc[i].bp_offset));
printf(" signal:%d\n", orc[i].signal);
}
elf_end(elf);
close(fd);
return 0;
}
|
