mdreloc.c revision 1.11
1 /* $NetBSD: mdreloc.c,v 1.11 2002/09/11 14:19:30 junyoung Exp $ */ 2 3 #include <sys/types.h> 4 #include <sys/stat.h> 5 6 #include "debug.h" 7 #include "rtld.h" 8 9 void 10 _rtld_setup_pltgot(const Obj_Entry *obj) 11 { 12 obj->pltgot[1] = (Elf_Addr) obj; 13 obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start; 14 } 15 16 int 17 _rtld_relocate_nonplt_objects(obj, self, dodebug) 18 const Obj_Entry *obj; 19 bool self; 20 bool dodebug; 21 { 22 const Elf_Rel *rel; 23 24 for (rel = obj->rel; rel < obj->rellim; rel++) { 25 Elf_Addr *where; 26 const Elf_Sym *def; 27 const Obj_Entry *defobj; 28 Elf_Addr tmp; 29 unsigned long symnum; 30 31 where = (Elf_Addr *)(obj->relocbase + rel->r_offset); 32 symnum = ELF_R_SYM(rel->r_info); 33 34 switch (ELF_R_TYPE(rel->r_info)) { 35 case R_TYPE(NONE): 36 break; 37 38 #if 1 /* XXX should not occur */ 39 case R_TYPE(PC24): { /* word32 S - P + A */ 40 Elf32_Sword addend; 41 42 /* 43 * Extract addend and sign-extend if needed. 44 */ 45 addend = *where; 46 if (addend & 0x00800000) 47 addend |= 0xff000000; 48 49 def = _rtld_find_symdef(symnum, obj, &defobj, false); 50 if (def == NULL) 51 return -1; 52 tmp = (Elf_Addr)obj->relocbase + def->st_value 53 - (Elf_Addr)where + (addend << 2); 54 if ((tmp & 0xfe000000) != 0xfe000000 && 55 (tmp & 0xfe000000) != 0) { 56 _rtld_error( 57 "%s: R_ARM_PC24 relocation @ %p to %s failed " 58 "(displacement %ld (%#lx) out of range)", 59 obj->path, where, 60 obj->strtab + obj->symtab[symnum].st_name, 61 (long) tmp, (long) tmp); 62 return -1; 63 } 64 tmp >>= 2; 65 *where = (*where & 0xff000000) | (tmp & 0x00ffffff); 66 rdbg(dodebug, ("PC24 %s in %s --> %p @ %p in %s", 67 obj->strtab + obj->symtab[symnum].st_name, 68 obj->path, (void *)*where, where, defobj->path)); 69 break; 70 } 71 #endif 72 73 case R_TYPE(ABS32): /* word32 B + S + A */ 74 def = _rtld_find_symdef(symnum, obj, &defobj, false); 75 if (def == NULL) 76 return -1; 77 *where += (Elf_Addr)defobj->relocbase + def->st_value; 78 rdbg(dodebug, ("ABS32 %s in %s --> %p @ %p in %s", 79 obj->strtab + obj->symtab[symnum].st_name, 80 obj->path, (void *)*where, where, defobj->path)); 81 break; 82 83 case R_TYPE(GLOB_DAT): /* word32 B + S */ 84 def = _rtld_find_symdef(symnum, obj, &defobj, false); 85 if (def == NULL) 86 return -1; 87 *where = (Elf_Addr)(defobj->relocbase + def->st_value); 88 rdbg(dodebug, ("GLOB_DAT %s in %s --> %p @ %p in %s", 89 obj->strtab + obj->symtab[symnum].st_name, 90 obj->path, (void *)*where, where, defobj->path)); 91 break; 92 93 case R_TYPE(RELATIVE): /* word32 B + A */ 94 { 95 extern Elf_Addr _GLOBAL_OFFSET_TABLE_[]; 96 extern Elf_Addr _GOT_END_[]; 97 98 /* This is the ...iffy hueristic. */ 99 if (!self || 100 (caddr_t)where < (caddr_t)_GLOBAL_OFFSET_TABLE_ || 101 (caddr_t)where >= (caddr_t)_GOT_END_) { 102 *where += (Elf_Addr)obj->relocbase; 103 rdbg(dodebug, ("RELATIVE in %s --> %p", 104 obj->path, (void *)*where)); 105 } else 106 rdbg(dodebug, ("RELATIVE in %s stays at %p", 107 obj->path, (void *)*where)); 108 break; 109 } 110 111 case R_TYPE(COPY): 112 /* 113 * These are deferred until all other relocations have 114 * been done. All we do here is make sure that the 115 * COPY relocation is not in a shared library. They 116 * are allowed only in executable files. 117 */ 118 if (obj->isdynamic) { 119 _rtld_error( 120 "%s: Unexpected R_COPY relocation in shared library", 121 obj->path); 122 return -1; 123 } 124 rdbg(dodebug, ("COPY (avoid in main)")); 125 break; 126 127 default: 128 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, " 129 "contents = %p, symbol = %s", 130 symnum, (u_long)ELF_R_TYPE(rel->r_info), 131 (void *)rel->r_offset, (void *)*where, 132 obj->strtab + obj->symtab[symnum].st_name)); 133 _rtld_error("%s: Unsupported relocation type %ld " 134 "in non-PLT relocations\n", 135 obj->path, (u_long) ELF_R_TYPE(rel->r_info)); 136 return -1; 137 } 138 } 139 return 0; 140 } 141 142 int 143 _rtld_relocate_plt_lazy(obj, dodebug) 144 const Obj_Entry *obj; 145 bool dodebug; 146 { 147 const Elf_Rel *rel; 148 149 if (!obj->isdynamic) 150 return 0; 151 152 for (rel = obj->pltrel; rel < obj->pltrellim; rel++) { 153 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rel->r_offset); 154 155 assert(ELF_R_TYPE(rel->r_info) == R_TYPE(JUMP_SLOT)); 156 157 /* Just relocate the GOT slots pointing into the PLT */ 158 *where += (Elf_Addr)obj->relocbase; 159 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path, 160 (void *)*where)); 161 } 162 163 return 0; 164 } 165 166 int 167 _rtld_relocate_plt_object(obj, rela, addrp, dodebug) 168 const Obj_Entry *obj; 169 const Elf_Rela *rela; 170 caddr_t *addrp; 171 bool dodebug; 172 { 173 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 174 Elf_Addr new_value; 175 const Elf_Sym *def; 176 const Obj_Entry *defobj; 177 178 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 179 180 def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true); 181 if (def == NULL) 182 return -1; 183 184 new_value = (Elf_Addr)(defobj->relocbase + def->st_value); 185 rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p", 186 defobj->strtab + def->st_name, (void *)*where, (void *)new_value)); 187 if (*where != new_value) 188 *where = new_value; 189 190 *addrp = (caddr_t)new_value; 191 return 0; 192 } 193
Indexes created Tue Sep 30 11:09:46 GMT 2025