diff options
| author | Dale Rahn <drahn@cvs.openbsd.org> | 2002-12-18 19:20:03 +0000 |
|---|---|---|
| committer | Dale Rahn <drahn@cvs.openbsd.org> | 2002-12-18 19:20:03 +0000 |
| commit | 8f09080005732280987e9c3a5d4dfb4b7ff1d0ff (patch) | |
| tree | 40b3f487a7bc16dc52413c5ce00772fd5430b427 /libexec/ld.so/mips | |
| parent | 90f6776918c0b71f3eac3550935610833e3ed1ef (diff) | |
Prepare for an upcoming ELF executable change. This will allow ld.so to
protect the GOT and PLT sections of the executable from being overwritten.
This behavior is enabled by changes in the executable/shared object layout,
and does not occur without the ld changes.
Diffstat (limited to 'libexec/ld.so/mips')
| -rw-r--r-- | libexec/ld.so/mips/rtld_machine.c | 39 |
1 files changed, 38 insertions, 1 deletions
diff --git a/libexec/ld.so/mips/rtld_machine.c b/libexec/ld.so/mips/rtld_machine.c index b58e689e7fa..45467e3b9cf 100644 --- a/libexec/ld.so/mips/rtld_machine.c +++ b/libexec/ld.so/mips/rtld_machine.c @@ -1,4 +1,4 @@ -/* $OpenBSD: rtld_machine.c,v 1.9 2002/11/14 15:15:54 drahn Exp $ */ +/* $OpenBSD: rtld_machine.c,v 1.10 2002/12/18 19:20:02 drahn Exp $ */ /* * Copyright (c) 1998-2002 Opsycon AB, Sweden. @@ -129,6 +129,8 @@ _dl_md_reloc_got(elf_object_t *object, int lazy) const Elf32_Sym *symp; const Elf32_Sym *this; const char *strt; + Elf_Addr ooff; + const Elf_Sym *this; if (object->status & STAT_GOT_DONE) return; @@ -159,6 +161,34 @@ _dl_md_reloc_got(elf_object_t *object, int lazy) n = object->Dyn.info[DT_MIPS_SYMTABNO - DT_LOPROC + DT_NUM] - object->Dyn.info[DT_MIPS_GOTSYM - DT_LOPROC + DT_NUM]; + this = NULL; + ooff = _dl_find_symbol("__got_start", object, &this, + SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT, + NULL); + if (this != NULL) + object->got_addr = ooff + this->st_value; + + this = NULL; + ooff = _dl_find_symbol("__got_end", object, &this, + SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT, + NULL); + if (this != NULL) + object->got_size = ooff + this->st_value - object->got_addr; + + this = NULL; + ooff = _dl_find_symbol("__plt_start", object, &this, + SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT, + NULL); + if (this != NULL) + object->plt_addr = ooff + this->st_value; + + this = NULL; + ooff = _dl_find_symbol("__plt_end", object, &this, + SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, SYM_NOTPLT, + NULL); + if (this != NULL) + object->plt_size = ooff + this->st_value - object->plt_addr; + /* * Then do all global references according to the ABI. * Quickstart is not yet implemented. @@ -195,4 +225,11 @@ DL_DEB(("got: '%s' = %x\n", strt + symp->st_name, symp->st_value)); symp++; } object->status |= STAT_GOT_DONE; + + if (object->got_addr != NULL && object->got_size != 0) + _dl_mprotect((void*)object->got_addr, object->got_size, + PROT_READ); + if (object->plt_addr != NULL && object->plt_size != 0) + _dl_mprotect((void*)object->plt_addr, object->plt_size, + PROT_READ|PROT_EXEC); } |