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 "orc.h" 8 #include "warn.h" 9 10 static const char *reg_name(unsigned int reg) 11 { 12 switch (reg) { 13 case ORC_REG_PREV_SP: 14 return "prevsp"; 15 case ORC_REG_DX: 16 return "dx"; 17 case ORC_REG_DI: 18 return "di"; 19 case ORC_REG_BP: 20 return "bp"; 21 case ORC_REG_SP: 22 return "sp"; 23 case ORC_REG_R10: 24 return "r10"; 25 case ORC_REG_R13: 26 return "r13"; 27 case ORC_REG_BP_INDIRECT: 28 return "bp(ind)"; 29 case ORC_REG_SP_INDIRECT: 30 return "sp(ind)"; 31 default: 32 return "?"; 33 } 34 } 35 36 static const char *orc_type_name(unsigned int type) 37 { 38 switch (type) { 39 case ORC_TYPE_CALL: 40 return "call"; 41 case ORC_TYPE_REGS: 42 return "regs"; 43 case ORC_TYPE_REGS_IRET: 44 return "iret"; 45 default: 46 return "?"; 47 } 48 } 49 50 static void print_reg(unsigned int reg, int offset) 51 { 52 if (reg == ORC_REG_BP_INDIRECT) 53 printf("(bp%+d)", offset); 54 else if (reg == ORC_REG_SP_INDIRECT) 55 printf("(sp%+d)", offset); 56 else if (reg == ORC_REG_UNDEFINED) 57 printf("(und)"); 58 else 59 printf("%s%+d", reg_name(reg), offset); 60 } 61 62 int orc_dump(const char *_objname) 63 { 64 int fd, nr_entries, i, *orc_ip = NULL, orc_size = 0; 65 struct orc_entry *orc = NULL; 66 char *name; 67 size_t nr_sections; 68 Elf64_Addr orc_ip_addr = 0; 69 size_t shstrtab_idx; 70 Elf *elf; 71 Elf_Scn *scn; 72 GElf_Shdr sh; 73 GElf_Rela rela; 74 GElf_Sym sym; 75 Elf_Data *data, *symtab = NULL, *rela_orc_ip = NULL; 76 77 78 objname = _objname; 79 80 elf_version(EV_CURRENT); 81 82 fd = open(objname, O_RDONLY); 83 if (fd == -1) { 84 perror("open"); 85 return -1; 86 } 87 88 elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); 89 if (!elf) { 90 WARN_ELF("elf_begin"); 91 return -1; 92 } 93 94 if (elf_getshdrnum(elf, &nr_sections)) { 95 WARN_ELF("elf_getshdrnum"); 96 return -1; 97 } 98 99 if (elf_getshdrstrndx(elf, &shstrtab_idx)) { 100 WARN_ELF("elf_getshdrstrndx"); 101 return -1; 102 } 103 104 for (i = 0; i < nr_sections; i++) { 105 scn = elf_getscn(elf, i); 106 if (!scn) { 107 WARN_ELF("elf_getscn"); 108 return -1; 109 } 110 111 if (!gelf_getshdr(scn, &sh)) { 112 WARN_ELF("gelf_getshdr"); 113 return -1; 114 } 115 116 name = elf_strptr(elf, shstrtab_idx, sh.sh_name); 117 if (!name) { 118 WARN_ELF("elf_strptr"); 119 return -1; 120 } 121 122 data = elf_getdata(scn, NULL); 123 if (!data) { 124 WARN_ELF("elf_getdata"); 125 return -1; 126 } 127 128 if (!strcmp(name, ".symtab")) { 129 symtab = data; 130 } else if (!strcmp(name, ".orc_unwind")) { 131 orc = data->d_buf; 132 orc_size = sh.sh_size; 133 } else if (!strcmp(name, ".orc_unwind_ip")) { 134 orc_ip = data->d_buf; 135 orc_ip_addr = sh.sh_addr; 136 } else if (!strcmp(name, ".rela.orc_unwind_ip")) { 137 rela_orc_ip = data; 138 } 139 } 140 141 if (!symtab || !orc || !orc_ip) 142 return 0; 143 144 if (orc_size % sizeof(*orc) != 0) { 145 WARN("bad .orc_unwind section size"); 146 return -1; 147 } 148 149 nr_entries = orc_size / sizeof(*orc); 150 for (i = 0; i < nr_entries; i++) { 151 if (rela_orc_ip) { 152 if (!gelf_getrela(rela_orc_ip, i, &rela)) { 153 WARN_ELF("gelf_getrela"); 154 return -1; 155 } 156 157 if (!gelf_getsym(symtab, GELF_R_SYM(rela.r_info), &sym)) { 158 WARN_ELF("gelf_getsym"); 159 return -1; 160 } 161 162 scn = elf_getscn(elf, sym.st_shndx); 163 if (!scn) { 164 WARN_ELF("elf_getscn"); 165 return -1; 166 } 167 168 if (!gelf_getshdr(scn, &sh)) { 169 WARN_ELF("gelf_getshdr"); 170 return -1; 171 } 172 173 name = elf_strptr(elf, shstrtab_idx, sh.sh_name); 174 if (!name || !*name) { 175 WARN_ELF("elf_strptr"); 176 return -1; 177 } 178 179 printf("%s+%llx:", name, (unsigned long long)rela.r_addend); 180 181 } else { 182 printf("%llx:", (unsigned long long)(orc_ip_addr + (i * sizeof(int)) + orc_ip[i])); 183 } 184 185 186 printf(" sp:"); 187 188 print_reg(orc[i].sp_reg, orc[i].sp_offset); 189 190 printf(" bp:"); 191 192 print_reg(orc[i].bp_reg, orc[i].bp_offset); 193 194 printf(" type:%s end:%d\n", 195 orc_type_name(orc[i].type), orc[i].end); 196 } 197 198 elf_end(elf); 199 close(fd); 200 201 return 0; 202 } 203