/* Do relocations for ELF dynamic linking. Copyright (C) 1995-2014 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ /* This file may be included twice, to define both `elf_dynamic_do_rel' and `elf_dynamic_do_rela'. */ #ifdef DO_RELA # define elf_dynamic_do_Rel elf_dynamic_do_Rela # define Rel Rela # define elf_machine_rel elf_machine_rela # define elf_machine_rel_relative elf_machine_rela_relative #endif #ifndef DO_ELF_MACHINE_REL_RELATIVE # define DO_ELF_MACHINE_REL_RELATIVE(map, l_addr, relative) \ elf_machine_rel_relative (l_addr, relative, \ (void *) (l_addr + relative->r_offset)) #endif /* Perform the relocations in MAP on the running program image as specified by RELTAG, SZTAG. If LAZY is nonzero, this is the first pass on PLT relocations; they should be set up to call _dl_runtime_resolve, rather than fully resolved now. */ auto inline void __attribute__ ((always_inline)) elf_dynamic_do_Rel (struct link_map *map, ElfW(Addr) reladdr, ElfW(Addr) relsize, __typeof (((ElfW(Dyn) *) 0)->d_un.d_val) nrelative, int lazy, int skip_ifunc) { const ElfW(Rel) *r = (const void *) reladdr; const ElfW(Rel) *end = (const void *) (reladdr + relsize); ElfW(Addr) l_addr = map->l_addr; # if defined ELF_MACHINE_IRELATIVE && !defined RTLD_BOOTSTRAP const ElfW(Rel) *r2 = NULL; const ElfW(Rel) *end2 = NULL; # endif #if (!defined DO_RELA || !defined ELF_MACHINE_PLT_REL) && !defined RTLD_BOOTSTRAP /* We never bind lazily during ld.so bootstrap. Unfortunately gcc is not clever enough to see through all the function calls to realize that. */ if (lazy) { /* Doing lazy PLT relocations; they need very little info. */ for (; r < end; ++r) # ifdef ELF_MACHINE_IRELATIVE if (ELFW(R_TYPE) (r->r_info) == ELF_MACHINE_IRELATIVE) { if (r2 == NULL) r2 = r; end2 = r; } else # endif elf_machine_lazy_rel (map, l_addr, r, skip_ifunc); # ifdef ELF_MACHINE_IRELATIVE if (r2 != NULL) for (; r2 <= end2; ++r2) if (ELFW(R_TYPE) (r2->r_info) == ELF_MACHINE_IRELATIVE) elf_machine_lazy_rel (map, l_addr, r2, skip_ifunc); # endif } else #endif { const ElfW(Sym) *const symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]); const ElfW(Rel) *relative = r; r += nrelative; #ifndef RTLD_BOOTSTRAP /* This is defined in rtld.c, but nowhere in the static libc.a; make the reference weak so static programs can still link. This declaration cannot be done when compiling rtld.c (i.e. #ifdef RTLD_BOOTSTRAP) because rtld.c contains the common defn for _dl_rtld_map, which is incompatible with a weak decl in the same file. */ # ifndef SHARED weak_extern (GL(dl_rtld_map)); # endif if (map != &GL(dl_rtld_map)) /* Already done in rtld itself. */ # if !defined DO_RELA || defined ELF_MACHINE_REL_RELATIVE /* Rela platforms get the offset from r_addend and this must be copied in the relocation address. Therefore we can skip the relative relocations only if this is for rel relocations or rela relocations if they are computed as memory_loc += l_addr... */ if (l_addr != 0) # else /* ...or we know the object has been prelinked. */ if (l_addr != 0 || ! map->l_info[VALIDX(DT_GNU_PRELINKED)]) # endif #endif for (; relative < r; ++relative) DO_ELF_MACHINE_REL_RELATIVE (map, l_addr, relative); #ifdef RTLD_BOOTSTRAP /* The dynamic linker always uses versioning. */ assert (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL); #else if (map->l_info[VERSYMIDX (DT_VERSYM)]) #endif { const ElfW(Half) *const version = (const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]); for (; r < end; ++r) { #if defined ELF_MACHINE_IRELATIVE && !defined RTLD_BOOTSTRAP if (ELFW(R_TYPE) (r->r_info) == ELF_MACHINE_IRELATIVE) { if (r2 == NULL) r2 = r; end2 = r; continue; } #endif ElfW(Half) ndx = version[ELFW(R_SYM) (r->r_info)] & 0x7fff; elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], &map->l_versions[ndx], (void *) (l_addr + r->r_offset), skip_ifunc); } #if defined ELF_MACHINE_IRELATIVE && !defined RTLD_BOOTSTRAP if (r2 != NULL) for (; r2 <= end2; ++r2) if (ELFW(R_TYPE) (r2->r_info) == ELF_MACHINE_IRELATIVE) { ElfW(Half) ndx = version[ELFW(R_SYM) (r2->r_info)] & 0x7fff; elf_machine_rel (map, r2, &symtab[ELFW(R_SYM) (r2->r_info)], &map->l_versions[ndx], (void *) (l_addr + r2->r_offset), skip_ifunc); } #endif } #ifndef RTLD_BOOTSTRAP else { for (; r < end; ++r) # ifdef ELF_MACHINE_IRELATIVE if (ELFW(R_TYPE) (r->r_info) == ELF_MACHINE_IRELATIVE) { if (r2 == NULL) r2 = r; end2 = r; } else # endif elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL, (void *) (l_addr + r->r_offset), skip_ifunc); # ifdef ELF_MACHINE_IRELATIVE if (r2 != NULL) for (; r2 <= end2; ++r2) if (ELFW(R_TYPE) (r2->r_info) == ELF_MACHINE_IRELATIVE) elf_machine_rel (map, r2, &symtab[ELFW(R_SYM) (r2->r_info)], NULL, (void *) (l_addr + r2->r_offset), skip_ifunc); # endif } #endif } } #undef elf_dynamic_do_Rel #undef Rel #undef elf_machine_rel #undef elf_machine_rel_relative #undef DO_ELF_MACHINE_REL_RELATIVE #undef DO_RELA