mdreloc.c revision 1.4
1 /* $NetBSD: mdreloc.c,v 1.4 2001/12/14 22:07:23 thorpej 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 #include <sys/types.h> 39 #include <sys/mman.h> 40 #include <err.h> 41 #include <errno.h> 42 #include <fcntl.h> 43 #include <stdarg.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <unistd.h> 48 #include <elf.h> 49 50 #include "debug.h" 51 #include "rtld.h" 52 53 extern Elf64_Addr _GLOBAL_OFFSET_TABLE_[]; 54 55 int 56 _rtld_relocate_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela, bool dodebug) 57 { 58 Elf64_Addr *where64; 59 Elf32_Addr *where32; 60 const Elf_Sym *def; 61 const Obj_Entry *defobj; 62 Elf64_Addr tmp64; 63 Elf32_Addr tmp32; 64 65 where64 = (Elf64_Addr *)(obj->relocbase + rela->r_offset); 66 where32 = (Elf32_Addr *)where64; 67 68 switch (ELF_R_TYPE(rela->r_info)) { 69 70 case R_TYPE(NONE): 71 break; 72 73 case R_TYPE(32): /* word32 S + A, truncate */ 74 case R_TYPE(32S): /* word32 S + A, signed truncate */ 75 case R_TYPE(GOT32): /* word32 G + A (XXX can we see these?) */ 76 def = _rtld_find_symdef(_rtld_objlist, rela->r_info, NULL, obj, 77 &defobj, false); 78 if (def == NULL) 79 return -1; 80 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + def->st_value + 81 rela->r_addend); 82 83 if (*where32 != tmp32) 84 *where32 = tmp32; 85 rdbg(dodebug, ("32/32S %s in %s --> %p in %s", 86 defobj->strtab + def->st_name, obj->path, 87 (void *)(unsigned long)*where32, defobj->path)); 88 break; 89 case R_TYPE(64): /* word64 S + A */ 90 def = _rtld_find_symdef(_rtld_objlist, rela->r_info, NULL, obj, 91 &defobj, false); 92 if (def == NULL) 93 return -1; 94 95 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value + 96 rela->r_addend); 97 98 if (*where64 != tmp64) 99 *where64 = tmp64; 100 rdbg(dodebug, ("64 %s in %s --> %p in %s", 101 defobj->strtab + def->st_name, obj->path, 102 (void *)*where64, defobj->path)); 103 break; 104 case R_TYPE(PC32): /* word32 S + A - P */ 105 def = _rtld_find_symdef(_rtld_objlist, rela->r_info, NULL, obj, 106 &defobj, false); 107 if (def == NULL) 108 return -1; 109 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + def->st_value + 110 rela->r_addend - (Elf64_Addr)where64); 111 if (*where32 != tmp32) 112 *where32 = tmp32; 113 rdbg(dodebug, ("PC32 %s in %s --> %p in %s", 114 defobj->strtab + def->st_name, obj->path, 115 (void *)(unsigned long)*where32, defobj->path)); 116 break; 117 case R_TYPE(GLOB_DAT): /* word64 S */ 118 def = _rtld_find_symdef(_rtld_objlist, rela->r_info, NULL, obj, 119 &defobj, false); 120 if (def == NULL) 121 return -1; 122 123 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value); 124 125 if (*where64 != tmp64) 126 *where64 = tmp64; 127 rdbg(dodebug, ("64 %s in %s --> %p in %s", 128 defobj->strtab + def->st_name, obj->path, 129 (void *)*where64, defobj->path)); 130 break; 131 case R_TYPE(RELATIVE): /* word64 B + A */ 132 tmp64 = (Elf64_Addr)(obj->relocbase + rela->r_addend); 133 if (*where64 != tmp64) 134 *where64 = tmp64; 135 rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path, 136 (void *)*where64)); 137 break; 138 139 case R_TYPE(COPY): 140 rdbg(dodebug, ("COPY")); 141 break; 142 143 default: 144 def = _rtld_find_symdef(_rtld_objlist, rela->r_info, NULL, obj, 145 &defobj, true); 146 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, " 147 "addend = %p, contents = %p, symbol = %s", 148 (u_long)ELF_R_SYM(rela->r_info), 149 (u_long)ELF_R_TYPE(rela->r_info), 150 (void *)rela->r_offset, (void *)rela->r_addend, 151 (void *)*where64, 152 def ? defobj->strtab + def->st_name : "??")); 153 _rtld_error("%s: Unsupported relocation type %ld " 154 "in non-PLT relocations\n", 155 obj->path, (u_long) ELF_R_TYPE(rela->r_info)); 156 return -1; 157 } 158 return 0; 159 } 160 161 162 163 int 164 _rtld_relocate_plt_object(Obj_Entry *obj, const Elf_Rela *rela, caddr_t *addrp, 165 bool bind_now, bool dodebug) 166 { 167 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 168 Elf_Addr new_value; 169 170 /* Fully resolve procedure addresses now */ 171 172 if (bind_now || obj->pltgot == NULL) { 173 const Elf_Sym *def; 174 const Obj_Entry *defobj; 175 176 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 177 178 def = _rtld_find_symdef(_rtld_objlist, rela->r_info, NULL, obj, 179 &defobj, true); 180 if (def == NULL) 181 return -1; 182 183 new_value = (Elf_Addr) 184 (defobj->relocbase + def->st_value + rela->r_addend); 185 rdbg(dodebug, ("bind now %d/fixup in %s --> old=%p new=%p", 186 (int)bind_now, 187 defobj->strtab + def->st_name, 188 (void *)*where, (void *)new_value)); 189 } else { 190 if (!obj->mainprog) { 191 /* Just relocate the GOT slots pointing into the PLT */ 192 new_value = *where + (Elf_Addr) obj->relocbase; 193 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path, 194 (void *)(unsigned long)*where)); 195 } else { 196 return 0; 197 } 198 } 199 /* 200 * Since this page is probably copy-on-write, let's not write 201 * it unless we really really have to. 202 */ 203 if (*where != new_value) 204 *where = new_value; 205 if (addrp != NULL) 206 *addrp = *(caddr_t *)(obj->relocbase + rela->r_offset) - 207 rela->r_addend; 208 return 0; 209 } 210
Indexes created Thu Oct 02 10:09:58 GMT 2025