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