1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2017 Josh Poimboeuf <jpoimboe@redhat.com>
4 */
5
6 #include <unistd.h>
7 #include <asm/orc_types.h>
8 #include <objtool/objtool.h>
9 #include <objtool/orc.h>
10 #include <objtool/warn.h>
11 #include <objtool/endianness.h>
12
orc_dump(const char * filename)13 int orc_dump(const char *filename)
14 {
15 int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0;
16 struct orc_entry *orc = NULL;
17 char *name;
18 size_t nr_sections;
19 Elf64_Addr orc_ip_addr = 0;
20 size_t shstrtab_idx, strtab_idx = 0;
21 Elf *elf;
22 Elf_Scn *scn;
23 GElf_Shdr sh;
24 GElf_Rela rela;
25 GElf_Sym sym;
26 Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL;
27 struct elf dummy_elf = {};
28
29 elf_version(EV_CURRENT);
30
31 fd = open(filename, O_RDONLY);
32 if (fd == -1) {
33 perror("open");
34 return -1;
35 }
36
37 elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
38 if (!elf) {
39 ERROR_ELF("elf_begin");
40 return -1;
41 }
42
43 if (!elf64_getehdr(elf)) {
44 ERROR_ELF("elf64_getehdr");
45 return -1;
46 }
47 memcpy(&dummy_elf.ehdr, elf64_getehdr(elf), sizeof(dummy_elf.ehdr));
48
49 if (elf_getshdrnum(elf, &nr_sections)) {
50 ERROR_ELF("elf_getshdrnum");
51 return -1;
52 }
53
54 if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
55 ERROR_ELF("elf_getshdrstrndx");
56 return -1;
57 }
58
59 for (i = 0; i < nr_sections; i++) {
60 scn = elf_getscn(elf, i);
61 if (!scn) {
62 ERROR_ELF("elf_getscn");
63 return -1;
64 }
65
66 if (!gelf_getshdr(scn, &sh)) {
67 ERROR_ELF("gelf_getshdr");
68 return -1;
69 }
70
71 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
72 if (!name) {
73 ERROR_ELF("elf_strptr");
74 return -1;
75 }
76
77 data = elf_getdata(scn, NULL);
78 if (!data) {
79 ERROR_ELF("elf_getdata");
80 return -1;
81 }
82
83 if (!strcmp(name, ".symtab")) {
84 symtab = data;
85 } else if (!strcmp(name, ".strtab")) {
86 strtab_idx = i;
87 } else if (!strcmp(name, ".orc_unwind")) {
88 orc = data->d_buf;
89 orc_size = sh.sh_size;
90 } else if (!strcmp(name, ".orc_unwind_ip")) {
91 orc_ip = data->d_buf;
92 orc_ip_addr = sh.sh_addr;
93 } else if (!strcmp(name, ".rela.orc_unwind_ip")) {
94 rela_orc_ip = data;
95 }
96 }
97
98 if (!symtab || !strtab_idx || !orc || !orc_ip)
99 return 0;
100
101 if (orc_size % sizeof(*orc) != 0) {
102 ERROR("bad .orc_unwind section size");
103 return -1;
104 }
105
106 nr_entries = orc_size / sizeof(*orc);
107 for (i = 0; i < nr_entries; i++) {
108 if (rela_orc_ip) {
109 if (!gelf_getrela(rela_orc_ip, i, &rela)) {
110 ERROR_ELF("gelf_getrela");
111 return -1;
112 }
113
114 if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
115 ERROR_ELF("gelf_getsym");
116 return -1;
117 }
118
119 if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
120 scn = elf_getscn(elf, sym.st_shndx);
121 if (!scn) {
122 ERROR_ELF("elf_getscn");
123 return -1;
124 }
125
126 if (!gelf_getshdr(scn, &sh)) {
127 ERROR_ELF("gelf_getshdr");
128 return -1;
129 }
130
131 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
132 if (!name) {
133 ERROR_ELF("elf_strptr");
134 return -1;
135 }
136 } else {
137 name = elf_strptr(elf, strtab_idx, sym.st_name);
138 if (!name) {
139 ERROR_ELF("elf_strptr");
140 return -1;
141 }
142 }
143
144 printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
145
146 } else {
147 printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
148 }
149
150 orc_print_dump(&dummy_elf, orc, i);
151 }
152
153 elf_end(elf);
154 close(fd);
155
156 return 0;
157 }
158