mdreloc.c revision 1.13
1 /* $NetBSD: mdreloc.c,v 1.13 2002/09/06 03:12:08 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 2001 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Frank van der Linden for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /* 39 * Copyright 1996 John D. Polstra. 40 * Copyright 1996 Matt Thomas <matt (at) 3am-software.com> 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by John Polstra. 54 * 4. The name of the author may not be used to endorse or promote products 55 * derived from this software without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 60 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 61 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 62 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 63 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 64 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 65 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 66 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 #include <sys/types.h> 70 #include <sys/mman.h> 71 #include <err.h> 72 #include <errno.h> 73 #include <fcntl.h> 74 #include <stdarg.h> 75 #include <stdio.h> 76 #include <stdlib.h> 77 #include <string.h> 78 #include <unistd.h> 79 #include <elf.h> 80 81 #include "debug.h" 82 #include "rtld.h" 83 84 void 85 _rtld_setup_pltgot(const Obj_Entry *obj) 86 { 87 obj->pltgot[1] = (Elf_Addr) obj; 88 obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start; 89 } 90 91 int 92 _rtld_relocate_nonplt_objects(const Obj_Entry *obj, bool dodebug) 93 { 94 const Elf_Rela *rela; 95 96 for (rela = obj->rela; rela < obj->relalim; rela++) { 97 Elf64_Addr *where64; 98 Elf32_Addr *where32; 99 const Elf_Sym *def; 100 const Obj_Entry *defobj; 101 Elf64_Addr tmp64; 102 Elf32_Addr tmp32; 103 unsigned long symnum; 104 105 where64 = (Elf64_Addr *)(obj->relocbase + rela->r_offset); 106 where32 = (Elf32_Addr *)where64; 107 symnum = ELF_R_SYM(rela->r_info); 108 109 switch (ELF_R_TYPE(rela->r_info)) { 110 case R_TYPE(NONE): 111 break; 112 113 case R_TYPE(32): /* word32 S + A, truncate */ 114 case R_TYPE(32S): /* word32 S + A, signed truncate */ 115 case R_TYPE(GOT32): /* word32 G + A (XXX can we see these?) */ 116 def = _rtld_find_symdef(symnum, obj, &defobj, false); 117 if (def == NULL) 118 return -1; 119 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + 120 def->st_value + rela->r_addend); 121 122 if (*where32 != tmp32) 123 *where32 = tmp32; 124 rdbg(dodebug, ("32/32S %s in %s --> %p in %s", 125 obj->strtab + obj->symtab[symnum].st_name, 126 obj->path, (void *)(unsigned long)*where32, 127 defobj->path)); 128 break; 129 case R_TYPE(64): /* word64 S + A */ 130 def = _rtld_find_symdef(symnum, obj, &defobj, false); 131 if (def == NULL) 132 return -1; 133 134 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value + 135 rela->r_addend); 136 137 if (*where64 != tmp64) 138 *where64 = tmp64; 139 rdbg(dodebug, ("64 %s in %s --> %p in %s", 140 obj->strtab + obj->symtab[symnum].st_name, 141 obj->path, (void *)*where64, defobj->path)); 142 break; 143 case R_TYPE(PC32): /* word32 S + A - P */ 144 def = _rtld_find_symdef(symnum, obj, &defobj, false); 145 if (def == NULL) 146 return -1; 147 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + 148 def->st_value + rela->r_addend - 149 (Elf64_Addr)where64); 150 if (*where32 != tmp32) 151 *where32 = tmp32; 152 rdbg(dodebug, ("PC32 %s in %s --> %p in %s", 153 obj->strtab + obj->symtab[symnum].st_name, 154 obj->path, (void *)(unsigned long)*where32, 155 defobj->path)); 156 break; 157 case R_TYPE(GLOB_DAT): /* word64 S */ 158 def = _rtld_find_symdef(symnum, obj, &defobj, false); 159 if (def == NULL) 160 return -1; 161 162 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value); 163 164 if (*where64 != tmp64) 165 *where64 = tmp64; 166 rdbg(dodebug, ("64 %s in %s --> %p in %s", 167 obj->strtab + obj->symtab[symnum].st_name, 168 obj->path, (void *)*where64, defobj->path)); 169 break; 170 case R_TYPE(RELATIVE): /* word64 B + A */ 171 tmp64 = (Elf64_Addr)(obj->relocbase + rela->r_addend); 172 if (*where64 != tmp64) 173 *where64 = tmp64; 174 rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path, 175 (void *)*where64)); 176 break; 177 178 case R_TYPE(COPY): 179 rdbg(dodebug, ("COPY")); 180 break; 181 182 default: 183 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, " 184 "addend = %p, contents = %p, symbol = %s", 185 symnum, (u_long)ELF_R_TYPE(rela->r_info), 186 (void *)rela->r_offset, (void *)rela->r_addend, 187 (void *)*where64, 188 obj->strtab + obj->symtab[symnum].st_name)); 189 _rtld_error("%s: Unsupported relocation type %ld " 190 "in non-PLT relocations\n", 191 obj->path, (u_long) ELF_R_TYPE(rela->r_info)); 192 return -1; 193 } 194 } 195 return 0; 196 } 197 198 int 199 _rtld_relocate_plt_lazy(obj, dodebug) 200 const Obj_Entry *obj; 201 bool dodebug; 202 { 203 const Elf_Rela *rela; 204 205 if (obj->mainprog) 206 return 0; 207 208 for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) { 209 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 210 211 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 212 213 /* Just relocate the GOT slots pointing into the PLT */ 214 *where += (Elf_Addr)obj->relocbase; 215 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path, 216 (void *)*where)); 217 } 218 219 return 0; 220 } 221 222 int 223 _rtld_relocate_plt_object(obj, rela, addrp, dodebug) 224 const Obj_Entry *obj; 225 const Elf_Rela *rela; 226 caddr_t *addrp; 227 bool dodebug; 228 { 229 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 230 Elf_Addr new_value; 231 const Elf_Sym *def; 232 const Obj_Entry *defobj; 233 234 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 235 236 def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true); 237 if (def == NULL) 238 return -1; 239 240 new_value = (Elf_Addr)(defobj->relocbase + def->st_value + 241 rela->r_addend); 242 rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p", 243 defobj->strtab + def->st_name, (void *)*where, (void *)new_value)); 244 if (*where != new_value) 245 *where = new_value; 246 247 *addrp = (caddr_t)(new_value - rela->r_addend); 248 return 0; 249 } 250
Indexes created Thu Oct 02 14:10:14 GMT 2025