freebsd-dev/stand/common/reloc_elf.c
Konstantin Belousov 85f794e126 Skip IRELATIVE relocations when loader processes ELF files.
ifuncs can be only called in the (early boot) kernel environment, so
postpone resolving until early stage of the kernel boot.  This commit
is performed in advance to make loaders on most machines updated
before ifuncs appear in the kernels.

Reviewed by:	emaste, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D13838
2018-01-11 13:57:30 +00:00

232 lines
6.1 KiB
C

/*-
* Copyright (c) 2003 Jake Burkholder.
* Copyright 1996-1998 John D. Polstra.
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* Copyright (c) 1998 Peter Wemm <peter@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <machine/elf.h>
#include <stand.h>
#define FREEBSD_ELF
#include <sys/link_elf.h>
#include "bootstrap.h"
#define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l)
/*
* Apply a single intra-module relocation to the data. `relbase' is the
* target relocation base for the section (i.e. it corresponds to where
* r_offset == 0). `dataaddr' is the relocated address corresponding to
* the start of the data, and `len' is the number of bytes.
*/
int
__elfN(reloc)(struct elf_file *ef, symaddr_fn *symaddr, const void *reldata,
int reltype, Elf_Addr relbase, Elf_Addr dataaddr, void *data, size_t len)
{
#ifdef __sparc__
Elf_Size w;
const Elf_Rela *a;
switch (reltype) {
case ELF_RELOC_RELA:
a = reldata;
if (relbase + a->r_offset >= dataaddr &&
relbase + a->r_offset < dataaddr + len) {
switch (ELF_R_TYPE(a->r_info)) {
case R_SPARC_RELATIVE:
w = relbase + a->r_addend;
bcopy(&w, (u_char *)data + (relbase +
a->r_offset - dataaddr), sizeof(w));
break;
default:
printf("\nunhandled relocation type %u\n",
(u_int)ELF_R_TYPE(a->r_info));
return (EFTYPE);
}
}
break;
}
return (0);
#elif (defined(__i386__) || defined(__amd64__)) && __ELF_WORD_SIZE == 64
Elf64_Addr *where, val;
Elf_Addr addend, addr;
Elf_Size rtype, symidx;
const Elf_Rel *rel;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
dataaddr);
addend = 0;
rtype = ELF_R_TYPE(rel->r_info);
symidx = ELF_R_SYM(rel->r_info);
addend = 0;
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
dataaddr);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
symidx = ELF_R_SYM(rela->r_info);
break;
default:
return (EINVAL);
}
if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
return (0);
if (reltype == ELF_RELOC_REL)
addend = *where;
/* XXX, definitions not available on i386. */
#define R_X86_64_64 1
#define R_X86_64_RELATIVE 8
#define R_X86_64_IRELATIVE 37
switch (rtype) {
case R_X86_64_64: /* S + A */
addr = symaddr(ef, symidx);
if (addr == 0)
return (ESRCH);
val = addr + addend;
*where = val;
break;
case R_X86_64_RELATIVE:
addr = (Elf_Addr)addend + relbase;
val = addr;
*where = val;
break;
case R_X86_64_IRELATIVE:
/* leave it to kernel */
break;
default:
printf("\nunhandled relocation type %u\n", (u_int)rtype);
return (EFTYPE);
}
return (0);
#elif defined(__i386__) && __ELF_WORD_SIZE == 32
Elf_Addr addend, addr, *where, val;
Elf_Size rtype, symidx;
const Elf_Rel *rel;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
dataaddr);
addend = 0;
rtype = ELF_R_TYPE(rel->r_info);
symidx = ELF_R_SYM(rel->r_info);
addend = 0;
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
dataaddr);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
symidx = ELF_R_SYM(rela->r_info);
break;
default:
return (EINVAL);
}
if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
return (0);
if (reltype == ELF_RELOC_REL)
addend = *where;
/* XXX, definitions not available on amd64. */
#define R_386_32 1 /* Add symbol value. */
#define R_386_GLOB_DAT 6 /* Set GOT entry to data address. */
#define R_386_RELATIVE 8 /* Add load address of shared object. */
#define R_386_IRELATIVE 42
switch (rtype) {
case R_386_RELATIVE:
addr = addend + relbase;
*where = addr;
break;
case R_386_32: /* S + A */
addr = symaddr(ef, symidx);
if (addr == 0)
return (ESRCH);
val = addr + addend;
*where = val;
break;
case R_386_IRELATIVE:
/* leave it to kernel */
break;
default:
printf("\nunhandled relocation type %u\n", (u_int)rtype);
return (EFTYPE);
}
return (0);
#elif defined(__powerpc__)
Elf_Size w;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_RELA:
rela = reldata;
if (relbase + rela->r_offset >= dataaddr &&
relbase + rela->r_offset < dataaddr + len) {
switch (ELF_R_TYPE(rela->r_info)) {
case R_PPC_RELATIVE:
w = relbase + rela->r_addend;
bcopy(&w, (u_char *)data + (relbase +
rela->r_offset - dataaddr), sizeof(w));
break;
default:
printf("\nunhandled relocation type %u\n",
(u_int)ELF_R_TYPE(rela->r_info));
return (EFTYPE);
}
}
break;
}
return (0);
#else
return (EOPNOTSUPP);
#endif
}