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
 13int 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}