mdreloc.c revision 1.8
1 /* $NetBSD: mdreloc.c,v 1.8 2002/09/05 18:25:48 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 extern Elf64_Addr _GLOBAL_OFFSET_TABLE_[]; 85 86 int 87 _rtld_relocate_plt_object(Obj_Entry *obj, const Elf_Rela *rela, caddr_t *addrp, 88 bool bind_now, bool dodebug) 89 { 90 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 91 Elf_Addr new_value; 92 93 /* Fully resolve procedure addresses now */ 94 95 if (bind_now || obj->pltgot == NULL) { 96 const Elf_Sym *def; 97 const Obj_Entry *defobj; 98 99 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 100 101 def = _rtld_find_symdef(rela->r_info, obj, &defobj, true); 102 if (def == NULL) 103 return -1; 104 105 new_value = (Elf_Addr) 106 (defobj->relocbase + def->st_value + rela->r_addend); 107 rdbg(dodebug, ("bind now %d/fixup in %s --> old=%p new=%p", 108 (int)bind_now, 109 defobj->strtab + def->st_name, 110 (void *)*where, (void *)new_value)); 111 } else { 112 if (!obj->mainprog) { 113 /* Just relocate the GOT slots pointing into the PLT */ 114 new_value = *where + (Elf_Addr) obj->relocbase; 115 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path, 116 (void *)(unsigned long)*where)); 117 } else { 118 return 0; 119 } 120 } 121 /* 122 * Since this page is probably copy-on-write, let's not write 123 * it unless we really really have to. 124 */ 125 if (*where != new_value) 126 *where = new_value; 127 if (addrp != NULL) 128 *addrp = *(caddr_t *)(obj->relocbase + rela->r_offset) - 129 rela->r_addend; 130 return 0; 131 } 132 133 void 134 _rtld_setup_pltgot(const Obj_Entry *obj) 135 { 136 obj->pltgot[1] = (Elf_Addr) obj; 137 obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start; 138 } 139 140 int 141 _rtld_relocate_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela, bool dodebug) 142 { 143 Elf64_Addr *where64; 144 Elf32_Addr *where32; 145 const Elf_Sym *def; 146 const Obj_Entry *defobj; 147 Elf64_Addr tmp64; 148 Elf32_Addr tmp32; 149 150 where64 = (Elf64_Addr *)(obj->relocbase + rela->r_offset); 151 where32 = (Elf32_Addr *)where64; 152 153 switch (ELF_R_TYPE(rela->r_info)) { 154 155 case R_TYPE(NONE): 156 break; 157 158 case R_TYPE(32): /* word32 S + A, truncate */ 159 case R_TYPE(32S): /* word32 S + A, signed truncate */ 160 case R_TYPE(GOT32): /* word32 G + A (XXX can we see these?) */ 161 def = _rtld_find_symdef(rela->r_info, obj, &defobj, false); 162 if (def == NULL) 163 return -1; 164 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + def->st_value + 165 rela->r_addend); 166 167 if (*where32 != tmp32) 168 *where32 = tmp32; 169 rdbg(dodebug, ("32/32S %s in %s --> %p in %s", 170 defobj->strtab + def->st_name, obj->path, 171 (void *)(unsigned long)*where32, defobj->path)); 172 break; 173 case R_TYPE(64): /* word64 S + A */ 174 def = _rtld_find_symdef(rela->r_info, obj, &defobj, false); 175 if (def == NULL) 176 return -1; 177 178 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value + 179 rela->r_addend); 180 181 if (*where64 != tmp64) 182 *where64 = tmp64; 183 rdbg(dodebug, ("64 %s in %s --> %p in %s", 184 defobj->strtab + def->st_name, obj->path, 185 (void *)*where64, defobj->path)); 186 break; 187 case R_TYPE(PC32): /* word32 S + A - P */ 188 def = _rtld_find_symdef(rela->r_info, obj, &defobj, false); 189 if (def == NULL) 190 return -1; 191 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + def->st_value + 192 rela->r_addend - (Elf64_Addr)where64); 193 if (*where32 != tmp32) 194 *where32 = tmp32; 195 rdbg(dodebug, ("PC32 %s in %s --> %p in %s", 196 defobj->strtab + def->st_name, obj->path, 197 (void *)(unsigned long)*where32, defobj->path)); 198 break; 199 case R_TYPE(GLOB_DAT): /* word64 S */ 200 def = _rtld_find_symdef(rela->r_info, obj, &defobj, false); 201 if (def == NULL) 202 return -1; 203 204 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value); 205 206 if (*where64 != tmp64) 207 *where64 = tmp64; 208 rdbg(dodebug, ("64 %s in %s --> %p in %s", 209 defobj->strtab + def->st_name, obj->path, 210 (void *)*where64, defobj->path)); 211 break; 212 case R_TYPE(RELATIVE): /* word64 B + A */ 213 tmp64 = (Elf64_Addr)(obj->relocbase + rela->r_addend); 214 if (*where64 != tmp64) 215 *where64 = tmp64; 216 rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path, 217 (void *)*where64)); 218 break; 219 220 case R_TYPE(COPY): 221 rdbg(dodebug, ("COPY")); 222 break; 223 224 default: 225 def = _rtld_find_symdef(rela->r_info, obj, &defobj, true); 226 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, " 227 "addend = %p, contents = %p, symbol = %s", 228 (u_long)ELF_R_SYM(rela->r_info), 229 (u_long)ELF_R_TYPE(rela->r_info), 230 (void *)rela->r_offset, (void *)rela->r_addend, 231 (void *)*where64, 232 def ? defobj->strtab + def->st_name : "??")); 233 _rtld_error("%s: Unsupported relocation type %ld " 234 "in non-PLT relocations\n", 235 obj->path, (u_long) ELF_R_TYPE(rela->r_info)); 236 return -1; 237 } 238 return 0; 239 } 240
Indexes created Thu Oct 02 10:09:58 GMT 2025