libexec/ld.elf_so/arch/sh3/mdreloc.c

   1 /*      $NetBSD: mdreloc.c,v 1.31 2014/08/25 20:40:52 joerg Exp $       */
   2
   3 #include <sys/cdefs.h>
   4 #ifndef lint
   5 __RCSID("$NetBSD: mdreloc.c,v 1.31 2014/08/25 20:40:52 joerg Exp $");
   6 #endif /* not lint */
   7
   8 #include <sys/cdefs.h>
   9 #ifndef lint
  10 __RCSID("$NetBSD: mdreloc.c,v 1.31 2014/08/25 20:40:52 joerg Exp $");
  11 #endif /* not lint */
  12
  13 #include <sys/types.h>
  14 #include <sys/tls.h>
  15
  16 #include "debug.h"
  17 #include "rtld.h"
  18
  19 void _rtld_bind_start(void);
  20 void _rtld_relocate_nonplt_self(Elf_Dyn *, Elf_Addr);
  21 caddr_t _rtld_bind(const Obj_Entry *, Elf_Word);
  22 static inline int _rtld_relocate_plt_object(const Obj_Entry *,
  23     const Elf_Rela *, Elf_Addr *);
  24
  25 void
  26 _rtld_setup_pltgot(const Obj_Entry *obj)
  27 {
  28         obj->pltgot[1] = (Elf_Addr) obj;
  29         obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
  30 }
  31
  32 void
  33 _rtld_relocate_nonplt_self(Elf_Dyn *dynp, Elf_Addr relocbase)
  34 {
  35         const Elf_Rela *rela = 0, *relalim;
  36         Elf_Addr relasz = 0;
  37         Elf_Addr *where;
  38
  39         for (; dynp->d_tag != DT_NULL; dynp++) {
  40                 switch (dynp->d_tag) {
  41                 case DT_RELA:
  42                         rela = (const Elf_Rela *)(relocbase + dynp->d_un.d_ptr);
  43                         break;
  44                 case DT_RELASZ:
  45                         relasz = dynp->d_un.d_val;
  46                         break;
  47                 }
  48         }
  49         relalim = (const Elf_Rela *)((const uint8_t *)rela + relasz);
  50         for (; rela < relalim; rela++) {
  51                 where = (Elf_Addr *)(relocbase + rela->r_offset);
  52                 *where = (Elf_Addr)(relocbase + rela->r_addend);
  53         }
  54 }
  55
  56 int
  57 _rtld_relocate_nonplt_objects(Obj_Entry *obj)
  58 {
  59         const Elf_Rela *rela;
  60
  61         for (rela = obj->rela; rela < obj->relalim; rela++) {
  62                 Elf_Addr        *where;
  63                 const Elf_Sym   *def;
  64                 const Obj_Entry *defobj;
  65                 Elf_Addr         tmp;
  66                 unsigned long    symnum;
  67
  68                 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
  69                 symnum = ELF_R_SYM(rela->r_info);
  70
  71                 switch (ELF_R_TYPE(rela->r_info)) {
  72                 case R_TYPE(NONE):
  73                         break;
  74
  75 #if 1 /* XXX should not occur */
  76                 case R_TYPE(GOT32):
  77                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
  78                         if (def == NULL)
  79                                 return -1;
  80
  81                         tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
  82                             rela->r_addend);
  83                         if (*where != tmp)
  84                                 *where = tmp;
  85                         rdbg(("GOT32 %s in %s --> %p in %s",
  86                             obj->strtab + obj->symtab[symnum].st_name,
  87                             obj->path, (void *)*where, defobj->path));
  88                         break;
  89
  90                 case R_TYPE(REL32):
  91                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
  92                         if (def == NULL)
  93                                 return -1;
  94
  95                         tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
  96                             rela->r_addend) - (Elf_Addr)where;
  97                         if (*where != tmp)
  98                                 *where = tmp;
  99                         rdbg(("PC32 %s in %s --> %p in %s",
 100                             obj->strtab + obj->symtab[symnum].st_name,
 101                             obj->path, (void *)*where, defobj->path));
 102                         break;
 103 #endif
 104
 105                 case R_TYPE(DIR32):
 106                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
 107                         if (def == NULL)
 108                                 return -1;
 109
 110                         tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
 111                             rela->r_addend);
 112                         if (*where != tmp)
 113                                 *where = tmp;
 114                         rdbg(("32 %s in %s --> %p in %s",
 115                             obj->strtab + obj->symtab[symnum].st_name,
 116                             obj->path, (void *)*where, defobj->path));
 117                         break;
 118
 119                 case R_TYPE(GLOB_DAT):
 120                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
 121                         if (def == NULL)
 122                                 return -1;
 123
 124                         tmp = (Elf_Addr)(defobj->relocbase + def->st_value) +
 125                             rela->r_addend;
 126                         if (*where != tmp)
 127                                 *where = tmp;
 128                         rdbg(("GLOB_DAT %s in %s --> %p in %s",
 129                             obj->strtab + obj->symtab[symnum].st_name,
 130                             obj->path, (void *)*where, defobj->path));
 131                         break;
 132
 133                 case R_TYPE(RELATIVE):
 134                         if (rela->r_addend)
 135                                 *where = (Elf_Addr)obj->relocbase + rela->r_addend;
 136                         else
 137                                 *where += (Elf_Addr)obj->relocbase;
 138                         rdbg(("RELATIVE in %s --> %p", obj->path,
 139                             (void *)*where));
 140                         break;
 141
 142                 case R_TYPE(COPY):
 143                         /*
 144                          * These are deferred until all other relocations have
 145                          * been done.  All we do here is make sure that the
 146                          * COPY relocation is not in a shared library.  They
 147                          * are allowed only in executable files.
 148                          */
 149                         if (obj->isdynamic) {
 150                                 _rtld_error(
 151                         "%s: Unexpected R_COPY relocation in shared library",
 152                                     obj->path);
 153                                 return -1;
 154                         }
 155                         rdbg(("COPY (avoid in main)"));
 156                         break;
 157
 158                 case R_TYPE(TLS_DTPOFF32):
 159                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
 160                         if (def == NULL)
 161                                 return -1;
 162
 163                         *where = (Elf_Addr)(def->st_value);
 164
 165                         rdbg(("TLS_DTPOFF32 %s in %s --> %p",
 166                             obj->strtab + obj->symtab[symnum].st_name,
 167                             obj->path, (void *)*where));
 168
 169                         break;
 170                 case R_TYPE(TLS_DTPMOD32):
 171                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
 172                         if (def == NULL)
 173                                 return -1;
 174
 175                         *where = (Elf_Addr)(defobj->tlsindex);
 176
 177                         rdbg(("TLS_DTPMOD32 %s in %s --> %p",
 178                             obj->strtab + obj->symtab[symnum].st_name,
 179                             obj->path, (void *)*where));
 180
 181                         break;
 182
 183                 case R_TYPE(TLS_TPOFF32):
 184                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
 185                         if (def == NULL)
 186                                 return -1;
 187
 188                         if (!defobj->tls_done &&
 189                             _rtld_tls_offset_allocate(obj))
 190                                 return -1;
 191
 192                         *where = (Elf_Addr)def->st_value +
 193                             rela->r_addend + defobj->tlsoffset +
 194                             sizeof(struct tls_tcb);
 195
 196                         rdbg(("TLS_TPOFF32 %s in %s --> %p",
 197                             obj->strtab + obj->symtab[symnum].st_name,
 198                             obj->path, (void *)*where));
 199                         break;
 200
 201                 default:
 202                         rdbg(("sym = %lu, type = %lu, offset = %p, "
 203                             "addend = %p, contents = %p, symbol = %s",
 204                             symnum, (u_long)ELF_R_TYPE(rela->r_info),
 205                             (void *)rela->r_offset, (void *)rela->r_addend,
 206                             (void *)*where,
 207                             obj->strtab + obj->symtab[symnum].st_name));
 208                         _rtld_error("%s: Unsupported relocation type %ld "
 209                             "in non-PLT relocations",
 210                             obj->path, (u_long) ELF_R_TYPE(rela->r_info));
 211                         return -1;
 212                 }
 213         }
 214         return 0;
 215 }
 216
 217 int
 218 _rtld_relocate_plt_lazy(const Obj_Entry *obj)
 219 {
 220         const Elf_Rela *rela;
 221
 222         if (!obj->relocbase)
 223                 return 0;
 224
 225         for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
 226                 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
 227
 228                 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
 229
 230                 /* Just relocate the GOT slots pointing into the PLT */
 231                 *where += (Elf_Addr)obj->relocbase;
 232                 rdbg(("fixup !main in %s --> %p", obj->path, (void *)*where));
 233         }
 234
 235         return 0;
 236 }
 237
 238 caddr_t
 239 _rtld_bind(const Obj_Entry *obj, Elf_Word reloff)
 240 {
 241         const Elf_Rela *rela = (const Elf_Rela *)((const uint8_t *)obj->pltrela + reloff);
 242         Elf_Addr new_value;
 243         int err;
 244
 245         new_value = 0;  /* XXX gcc */
 246
 247         _rtld_shared_enter();
 248         err = _rtld_relocate_plt_object(obj, rela, &new_value);
 249         if (err)
 250                 _rtld_die();
 251         _rtld_shared_exit();
 252
 253         return (caddr_t)new_value;
 254 }
 255
 256 int
 257 _rtld_relocate_plt_objects(const Obj_Entry *obj)
 258 {
 259         const Elf_Rela *rela = obj->pltrela;
 260
 261         for (; rela < obj->pltrelalim; rela++)
 262                 if (_rtld_relocate_plt_object(obj, rela, NULL) < 0)
 263                         return -1;
 264
 265         return 0;
 266 }
 267
 268 static inline int
 269 _rtld_relocate_plt_object(const Obj_Entry *obj, const Elf_Rela *rela, Elf_Addr *tp)
 270 {
 271         Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
 272         Elf_Addr new_value;
 273         const Elf_Sym  *def;
 274         const Obj_Entry *defobj;
 275         unsigned long info = rela->r_info;
 276
 277         assert(ELF_R_TYPE(info) == R_TYPE(JMP_SLOT));
 278
 279         def = _rtld_find_plt_symdef(ELF_R_SYM(info), obj, &defobj, tp != NULL);
 280         if (__predict_false(def == NULL))
 281                 return -1;
 282         if (__predict_false(def == &_rtld_sym_zero))
 283                 return 0;
 284
 285         if (ELF_ST_TYPE(def->st_info) == STT_GNU_IFUNC) {
 286                 if (tp == NULL)
 287                         return 0;
 288                 new_value = _rtld_resolve_ifunc(defobj, def);
 289         } else {
 290                 new_value = (Elf_Addr)(defobj->relocbase + def->st_value);
 291         }
 292         rdbg(("bind now/fixup in %s --> old=%p new=%p",
 293             defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
 294         if (*where != new_value)
 295                 *where = new_value;
 296
 297         if (tp)
 298                 *tp = new_value;
 299
 300         return 0;
 301 }