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
13 int orc_dump(const char *_objname)
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
30 objname = _objname;
31
32 elf_version(EV_CURRENT);
33
34 fd = open(objname, O_RDONLY);
35 if (fd == -1) {
36 perror("open");
37 return -1;
38 }
39
40 elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
41 if (!elf) {
42 WARN_ELF("elf_begin");
43 return -1;
44 }
45
46 if (!elf64_getehdr(elf)) {
47 WARN_ELF("elf64_getehdr");
48 return -1;
49 }
50 memcpy(&dummy_elf.ehdr, elf64_getehdr(elf), sizeof(dummy_elf.ehdr));
51
52 if (elf_getshdrnum(elf, &nr_sections)) {
53 WARN_ELF("elf_getshdrnum");
54 return -1;
55 }
56
57 if (elf_getshdrstrndx(elf, &shstrtab_idx)) {
58 WARN_ELF("elf_getshdrstrndx");
59 return -1;
60 }
61
62 for (i = 0; i < nr_sections; i++) {
63 scn = elf_getscn(elf, i);
64 if (!scn) {
65 WARN_ELF("elf_getscn");
66 return -1;
67 }
68
69 if (!gelf_getshdr(scn, &sh)) {
70 WARN_ELF("gelf_getshdr");
71 return -1;
72 }
73
74 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
75 if (!name) {
76 WARN_ELF("elf_strptr");
77 return -1;
78 }
79
80 data = elf_getdata(scn, NULL);
81 if (!data) {
82 WARN_ELF("elf_getdata");
83 return -1;
84 }
85
86 if (!strcmp(name, ".symtab")) {
87 symtab = data;
88 } else if (!strcmp(name, ".strtab")) {
89 strtab_idx = i;
90 } else if (!strcmp(name, ".orc_unwind")) {
91 orc = data->d_buf;
92 orc_size = sh.sh_size;
93 } else if (!strcmp(name, ".orc_unwind_ip")) {
94 orc_ip = data->d_buf;
95 orc_ip_addr = sh.sh_addr;
96 } else if (!strcmp(name, ".rela.orc_unwind_ip")) {
97 rela_orc_ip = data;
98 }
99 }
100
101 if (!symtab || !strtab_idx || !orc || !orc_ip)
102 return 0;
103
104 if (orc_size % sizeof(*orc) != 0) {
105 WARN("bad .orc_unwind section size");
106 return -1;
107 }
108
109 nr_entries = orc_size / sizeof(*orc);
110 for (i = 0; i < nr_entries; i++) {
111 if (rela_orc_ip) {
112 if (!gelf_getrela(rela_orc_ip, i, &rela)) {
113 WARN_ELF("gelf_getrela");
114 return -1;
115 }
116
117 if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) {
118 WARN_ELF("gelf_getsym");
119 return -1;
120 }
121
122 if (GELF_ST_TYPE(sym.st_info) == STT_SECTION) {
123 scn = elf_getscn(elf, sym.st_shndx);
124 if (!scn) {
125 WARN_ELF("elf_getscn");
126 return -1;
127 }
128
129 if (!gelf_getshdr(scn, &sh)) {
130 WARN_ELF("gelf_getshdr");
131 return -1;
132 }
133
134 name = elf_strptr(elf, shstrtab_idx, sh.sh_name);
135 if (!name) {
136 WARN_ELF("elf_strptr");
137 return -1;
138 }
139 } else {
140 name = elf_strptr(elf, strtab_idx, sym.st_name);
141 if (!name) {
142 WARN_ELF("elf_strptr");
143 return -1;
144 }
145 }
146
147 printf("%s+%llx:", name, (unsigned long long)rela.r_addend);
148
149 } else {
150 printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i]));
151 }
152
153 orc_print_dump(&dummy_elf, orc, i);
154 }
155
156 elf_end(elf);
157 close(fd);
158
159 return 0;
160 }
161
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