/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/* Get the x86 version of the relocation engine */
#define DO_RELOC_LIBLD_X86
#include <string.h>
#include <stdio.h>
#include <strings.h>
#include <sys/elf_amd64.h>
#include <debug.h>
#include <reloc.h>
#include <i386/machdep_x86.h>
#include "msg.h"
#include "_libld.h"
/*
* This module uses do_reloc_ld() to execute several synthesized relocations.
* That function expects to be passed two things that we need to construct
* here:
*
* 1) A Rel_desc descriptor for each relocation type, from which the
* rel_rtype field, and nothing else, is obtained. This is easily
* handled by constructing the necessary descriptors.
*
* 2) A function, which called with the Rel_desc descriptor, returns
* a string representing the name of the symbol associated with
* the descriptor. The usual function for this is ld_reloc_sym_name().
* However, that function will not work in this case, as these synthetic
* relocations do not have an associated symbol. We supply the
* syn_rdesc_sym_name() function to simply return the fixed name.
*/
static Rel_desc rdesc_r_amd64_gotpcrel = {
NULL, NULL, NULL, 0, 0, 0, R_AMD64_GOTPCREL };
static Rel_desc rdesc_r_amd64_32 = {
NULL, NULL, NULL, 0, 0, 0, R_AMD64_32 };
static Rel_desc rdesc_r_amd64_pc32 = {
NULL, NULL, NULL, 0, 0, 0, R_AMD64_PC32 };
/*ARGSUSED*/
static const char *
syn_rdesc_sym_name(Rel_desc *rdesc)
{
return (MSG_ORIG(MSG_SYM_PLTENT));
}
/*
* Search the GOT index list for a GOT entry with a matching reference and the
* proper addend.
*/
static Gotndx *
ld_find_got_ndx(Alist *alp, Gotref gref, Ofl_desc *ofl, Rel_desc *rdesc)
{
Aliste idx;
Gotndx *gnp;
assert(rdesc != 0);
if ((gref == GOT_REF_TLSLD) && ofl->ofl_tlsldgotndx)
return (ofl->ofl_tlsldgotndx);
for (ALIST_TRAVERSE(alp, idx, gnp)) {
if ((rdesc->rel_raddend == gnp->gn_addend) &&
(gnp->gn_gotref == gref)) {
return (gnp);
}
}
return (NULL);
}
static Xword
ld_calc_got_offset(Rel_desc *rdesc, Ofl_desc *ofl)
{
Os_desc *osp = ofl->ofl_osgot;
Sym_desc *sdp = rdesc->rel_sym;
Xword gotndx;
Gotref gref;
Gotndx *gnp;
if (rdesc->rel_flags & FLG_REL_DTLS)
gref = GOT_REF_TLSGD;
else if (rdesc->rel_flags & FLG_REL_MTLS)
gref = GOT_REF_TLSLD;
else if (rdesc->rel_flags & FLG_REL_STLS)
gref = GOT_REF_TLSIE;
else
gref = GOT_REF_GENERIC;
gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, rdesc);
assert(gnp);
gotndx = (Xword)gnp->gn_gotndx;
if ((rdesc->rel_flags & FLG_REL_DTLS) &&
(rdesc->rel_rtype == R_AMD64_DTPOFF64))
gotndx++;
return ((Xword)(osp->os_shdr->sh_addr + (gotndx * M_GOT_ENTSIZE)));
}
static Word
ld_init_rel(Rel_desc *reld, Word *typedata, void *reloc)
{
Rela *rel = (Rela *)reloc;
/* LINTED */
reld->rel_rtype = (Word)ELF_R_TYPE(rel->r_info, M_MACH);
reld->rel_roffset = rel->r_offset;
reld->rel_raddend = rel->r_addend;
*typedata = 0;
reld->rel_flags |= FLG_REL_RELA;
return ((Word)ELF_R_SYM(rel->r_info));
}
static void
ld_mach_eflags(Ehdr *ehdr, Ofl_desc *ofl)
{
ofl->ofl_dehdr->e_flags |= ehdr->e_flags;
}
static void
ld_mach_make_dynamic(Ofl_desc *ofl, size_t *cnt)
{
if (!(ofl->ofl_flags & FLG_OF_RELOBJ)) {
/*
* Create this entry if we are going to create a PLT table.
*/
if (ofl->ofl_pltcnt)
(*cnt)++; /* DT_PLTGOT */
}
}
static void
ld_mach_update_odynamic(Ofl_desc *ofl, Dyn **dyn)
{
if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) && ofl->ofl_pltcnt) {
(*dyn)->d_tag = DT_PLTGOT;
if (ofl->ofl_osgot)
(*dyn)->d_un.d_ptr = ofl->ofl_osgot->os_shdr->sh_addr;
else
(*dyn)->d_un.d_ptr = 0;
(*dyn)++;
}
}
static Xword
ld_calc_plt_addr(Sym_desc *sdp, Ofl_desc *ofl)
{
Xword value;
value = (Xword)(ofl->ofl_osplt->os_shdr->sh_addr) +
M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) * M_PLT_ENTSIZE);
return (value);
}
/*
* Build a single plt entry - code is:
* JMP *name1@GOTPCREL(%rip)
* PUSHL $index
* JMP .PLT0
*/
static uchar_t pltn_entry[M_PLT_ENTSIZE] = {
/* 0x00 jmpq *name1@GOTPCREL(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00,
/* 0x06 pushq $index */ 0x68, 0x00, 0x00, 0x00, 0x00,
/* 0x0b jmpq .plt0(%rip) */ 0xe9, 0x00, 0x00, 0x00, 0x00
/* 0x10 */
};
static uintptr_t
plt_entry(Ofl_desc * ofl, Sym_desc * sdp)
{
uchar_t *plt0, *pltent, *gotent;
Sword plt_off;
Word got_off;
Xword val1;
int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0;
got_off = sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE;
plt_off = M_PLT_RESERVSZ + ((sdp->sd_aux->sa_PLTndx - 1) *
M_PLT_ENTSIZE);
plt0 = (uchar_t *)(ofl->ofl_osplt->os_outdata->d_buf);
pltent = plt0 + plt_off;
gotent = (uchar_t *)(ofl->ofl_osgot->os_outdata->d_buf) + got_off;
bcopy(pltn_entry, pltent, sizeof (pltn_entry));
/*
* Fill in the got entry with the address of the next instruction.
*/
/* LINTED */
*(Word *)gotent = ofl->ofl_osplt->os_shdr->sh_addr + plt_off +
M_PLT_INSSIZE;
if (bswap)
/* LINTED */
*(Word *)gotent = ld_bswap_Word(*(Word *)gotent);
/*
* If '-z noreloc' is specified - skip the do_reloc_ld
* stage.
*/
if (!OFL_DO_RELOC(ofl))
return (1);
/*
* patchup:
* jmpq *name1@gotpcrel(%rip)
*
* NOTE: 0x06 represents next instruction.
*/
val1 = (ofl->ofl_osgot->os_shdr->sh_addr + got_off) -
(ofl->ofl_osplt->os_shdr->sh_addr + plt_off) - 0x06;
if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x02], &val1,
syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap,
ofl->ofl_lml) == 0) {
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL),
sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name));
return (S_ERROR);
}
/*
* patchup:
* pushq $pltndx
*/
val1 = (Xword)(sdp->sd_aux->sa_PLTndx - 1);
if (do_reloc_ld(&rdesc_r_amd64_32, &pltent[0x07], &val1,
syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap,
ofl->ofl_lml) == 0) {
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL),
sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name));
return (S_ERROR);
}
/*
* patchup:
* jmpq .plt0(%rip)
* NOTE: 0x10 represents next instruction. The rather complex
* series of casts is necessary to sign extend an offset into
* a 64-bit value while satisfying various compiler error
* checks. Handle with care.
*/
val1 = (Xword)((intptr_t)((uintptr_t)plt0 -
(uintptr_t)(&pltent[0x10])));
if (do_reloc_ld(&rdesc_r_amd64_pc32, &pltent[0x0c], &val1,
syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT), bswap,
ofl->ofl_lml) == 0) {
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLTNFAIL),
sdp->sd_aux->sa_PLTndx, demangle(sdp->sd_name));
return (S_ERROR);
}
return (1);
}
static uintptr_t
ld_perform_outreloc(Rel_desc * orsp, Ofl_desc * ofl, Boolean *remain_seen)
{
Os_desc * relosp, * osp = 0;
Word ndx;
Xword roffset, value;
Sxword raddend;
Rela rea;
char *relbits;
Sym_desc * sdp, * psym = (Sym_desc *)0;
int sectmoved = 0;
raddend = orsp->rel_raddend;
sdp = orsp->rel_sym;
/*
* If the section this relocation is against has been discarded
* (-zignore), then also discard (skip) the relocation itself.
*/
if (orsp->rel_isdesc && ((orsp->rel_flags &
(FLG_REL_GOT | FLG_REL_BSS | FLG_REL_PLT | FLG_REL_NOINFO)) == 0) &&
(orsp->rel_isdesc->is_flags & FLG_IS_DISCARD)) {
DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, orsp));
return (1);
}
/*
* If this is a relocation against a move table, or expanded move
* table, adjust the relocation entries.
*/
if (RELAUX_GET_MOVE(orsp))
ld_adj_movereloc(ofl, orsp);
/*
* If this is a relocation against a section then we need to adjust the
* raddend field to compensate for the new position of the input section
* within the new output section.
*/
if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) {
if (ofl->ofl_parsyms &&
(sdp->sd_isc->is_flags & FLG_IS_RELUPD) &&
/* LINTED */
(psym = ld_am_I_partial(orsp, orsp->rel_raddend))) {
DBG_CALL(Dbg_move_outsctadj(ofl->ofl_lml, psym));
sectmoved = 1;
if (ofl->ofl_flags & FLG_OF_RELOBJ)
raddend = psym->sd_sym->st_value;
else
raddend = psym->sd_sym->st_value -
psym->sd_isc->is_osdesc->os_shdr->sh_addr;
/* LINTED */
raddend += (Off)_elf_getxoff(psym->sd_isc->is_indata);
if (psym->sd_isc->is_shdr->sh_flags & SHF_ALLOC)
raddend +=
psym->sd_isc->is_osdesc->os_shdr->sh_addr;
} else {
/* LINTED */
raddend += (Off)_elf_getxoff(sdp->sd_isc->is_indata);
if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC)
raddend +=
sdp->sd_isc->is_osdesc->os_shdr->sh_addr;
}
}
value = sdp->sd_sym->st_value;
if (orsp->rel_flags & FLG_REL_GOT) {
/*
* Note: for GOT relative relocations on amd64
* we discard the addend. It was relevant
* to the reference - not to the data item
* being referenced (ie: that -4 thing).
*/
raddend = 0;
osp = ofl->ofl_osgot;
roffset = ld_calc_got_offset(orsp, ofl);
} else if (orsp->rel_flags & FLG_REL_PLT) {
/*
* Note that relocations for PLT's actually
* cause a relocation againt the GOT.
*/
osp = ofl->ofl_osplt;
roffset = (ofl->ofl_osgot->os_shdr->sh_addr) +
sdp->sd_aux->sa_PLTGOTndx * M_GOT_ENTSIZE;
raddend = 0;
if (plt_entry(ofl, sdp) == S_ERROR)
return (S_ERROR);
} else if (orsp->rel_flags & FLG_REL_BSS) {
/*
* This must be a R_AMD64_COPY. For these set the roffset to
* point to the new symbols location.
*/
osp = ofl->ofl_isbss->is_osdesc;
roffset = value;
/*
* The raddend doesn't mean anything in a R_SPARC_COPY
* relocation. Null it out because it can confuse people.
*/
raddend = 0;
} else {
osp = RELAUX_GET_OSDESC(orsp);
/*
* Calculate virtual offset of reference point; equals offset
* into section + vaddr of section for loadable sections, or
* offset plus section displacement for nonloadable sections.
*/
roffset = orsp->rel_roffset +
(Off)_elf_getxoff(orsp->rel_isdesc->is_indata);
if (!(ofl->ofl_flags & FLG_OF_RELOBJ))
roffset += orsp->rel_isdesc->is_osdesc->
os_shdr->sh_addr;
}
if ((osp == 0) || ((relosp = osp->os_relosdesc) == 0))
relosp = ofl->ofl_osrel;
/*
* Assign the symbols index for the output relocation. If the
* relocation refers to a SECTION symbol then it's index is based upon
* the output sections symbols index. Otherwise the index can be
* derived from the symbols index itself.
*/
if (orsp->rel_rtype == R_AMD64_RELATIVE)
ndx = STN_UNDEF;
else if ((orsp->rel_flags & FLG_REL_SCNNDX) ||
(ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION)) {
if (sectmoved == 0) {
/*
* Check for a null input section. This can
* occur if this relocation references a symbol
* generated by sym_add_sym().
*/
if (sdp->sd_isc && sdp->sd_isc->is_osdesc)
ndx = sdp->sd_isc->is_osdesc->os_identndx;
else
ndx = sdp->sd_shndx;
} else
ndx = ofl->ofl_parexpnndx;
} else
ndx = sdp->sd_symndx;
/*
* Add the symbols 'value' to the addend field.
*/
if (orsp->rel_flags & FLG_REL_ADVAL)
raddend += value;
/*
* The addend field for R_AMD64_DTPMOD64 means nothing. The addend
* is propagated in the corresponding R_AMD64_DTPOFF64 relocation.
*/
if (orsp->rel_rtype == R_AMD64_DTPMOD64)
raddend = 0;
relbits = (char *)relosp->os_outdata->d_buf;
rea.r_info = ELF_R_INFO(ndx, orsp->rel_rtype);
rea.r_offset = roffset;
rea.r_addend = raddend;
DBG_CALL(Dbg_reloc_out(ofl, ELF_DBG_LD, SHT_RELA, &rea, relosp->os_name,
ld_reloc_sym_name(orsp)));
/*
* Assert we haven't walked off the end of our relocation table.
*/
assert(relosp->os_szoutrels <= relosp->os_shdr->sh_size);
(void) memcpy((relbits + relosp->os_szoutrels),
(char *)&rea, sizeof (Rela));
relosp->os_szoutrels += (Xword)sizeof (Rela);
/*
* Determine if this relocation is against a non-writable, allocatable
* section. If so we may need to provide a text relocation diagnostic.
* Note that relocations against the .plt (R_AMD64_JUMP_SLOT) actually
* result in modifications to the .got.
*/
if (orsp->rel_rtype == R_AMD64_JUMP_SLOT)
osp = ofl->ofl_osgot;
ld_reloc_remain_entry(orsp, osp, ofl, remain_seen);
return (1);
}
/*
* amd64 Instructions for TLS processing
*/
static uchar_t tlsinstr_gd_ie[] = {
/*
* 0x00 movq %fs:0, %rax
*/
0x64, 0x48, 0x8b, 0x04, 0x25,
0x00, 0x00, 0x00, 0x00,
/*
* 0x09 addq x@gottpoff(%rip), %rax
*/
0x48, 0x03, 0x05, 0x00, 0x00,
0x00, 0x00
};
static uchar_t tlsinstr_gd_le[] = {
/*
* 0x00 movq %fs:0, %rax
*/
0x64, 0x48, 0x8b, 0x04, 0x25,
0x00, 0x00, 0x00, 0x00,
/*
* 0x09 leaq x@gottpoff(%rip), %rax
*/
0x48, 0x8d, 0x80, 0x00, 0x00,
0x00, 0x00
};
static uchar_t tlsinstr_ld_le[] = {
/*
* .byte 0x66
*/
0x66,
/*
* .byte 0x66
*/
0x66,
/*
* .byte 0x66
*/
0x66,
/*
* movq %fs:0, %rax
*/
0x64, 0x48, 0x8b, 0x04, 0x25,
0x00, 0x00, 0x00, 0x00
};
#define REX_B 0x1
#define REX_X 0x2
#define REX_R 0x4
#define REX_W 0x8
#define REX_PREFIX 0x40
#define REX_RW (REX_PREFIX | REX_R | REX_W)
#define REX_BW (REX_PREFIX | REX_B | REX_W)
#define REX_BRW (REX_PREFIX | REX_B | REX_R | REX_W)
#define REG_ESP 0x4
#define INSN_ADDMR 0x03 /* addq mem,reg */
#define INSN_ADDIR 0x81 /* addq imm,reg */
#define INSN_MOVMR 0x8b /* movq mem,reg */
#define INSN_MOVIR 0xc7 /* movq imm,reg */
#define INSN_LEA 0x8d /* leaq mem,reg */
static Fixupret
tls_fixups(Ofl_desc *ofl, Rel_desc *arsp)
{
Sym_desc *sdp = arsp->rel_sym;
Word rtype = arsp->rel_rtype;
uchar_t *offset;
offset = (uchar_t *)((uintptr_t)arsp->rel_roffset +
(uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata) +
(uintptr_t)RELAUX_GET_OSDESC(arsp)->os_outdata->d_buf);
/*
* Note that in certain of the original insn sequences below, the
* instructions are not necessarily adjacent
*/
if (sdp->sd_ref == REF_DYN_NEED) {
/*
* IE reference model
*/
switch (rtype) {
case R_AMD64_TLSGD:
/*
* GD -> IE
*
* Transition:
* 0x00 .byte 0x66
* 0x01 leaq x@tlsgd(%rip), %rdi
* 0x08 .word 0x6666
* 0x0a rex64
* 0x0b call __tls_get_addr@plt
* 0x10
* To:
* 0x00 movq %fs:0, %rax
* 0x09 addq x@gottpoff(%rip), %rax
* 0x10
*/
DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
R_AMD64_GOTTPOFF, arsp, ld_reloc_sym_name));
arsp->rel_rtype = R_AMD64_GOTTPOFF;
arsp->rel_roffset += 8;
arsp->rel_raddend = (Sxword)-4;
/*
* Adjust 'offset' to beginning of instruction
* sequence.
*/
offset -= 4;
(void) memcpy(offset, tlsinstr_gd_ie,
sizeof (tlsinstr_gd_ie));
return (FIX_RELOC);
case R_AMD64_PLT32:
/*
* Fixup done via the TLS_GD relocation.
*/
DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
R_AMD64_NONE, arsp, ld_reloc_sym_name));
return (FIX_DONE);
}
}
/*
* LE reference model
*/
switch (rtype) {
case R_AMD64_TLSGD:
/*
* GD -> LE
*
* Transition:
* 0x00 .byte 0x66
* 0x01 leaq x@tlsgd(%rip), %rdi
* 0x08 .word 0x6666
* 0x0a rex64
* 0x0b call __tls_get_addr@plt
* 0x10
* To:
* 0x00 movq %fs:0, %rax
* 0x09 leaq x@tpoff(%rax), %rax
* 0x10
*/
DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
R_AMD64_TPOFF32, arsp, ld_reloc_sym_name));
arsp->rel_rtype = R_AMD64_TPOFF32;
arsp->rel_roffset += 8;
arsp->rel_raddend = 0;
/*
* Adjust 'offset' to beginning of instruction sequence.
*/
offset -= 4;
(void) memcpy(offset, tlsinstr_gd_le, sizeof (tlsinstr_gd_le));
return (FIX_RELOC);
case R_AMD64_GOTTPOFF: {
/*
* IE -> LE
*
* Transition 1:
* movq %fs:0, %reg
* addq x@gottpoff(%rip), %reg
* To:
* movq %fs:0, %reg
* leaq x@tpoff(%reg), %reg
*
* Transition (as a special case):
* movq %fs:0, %r12/%rsp
* addq x@gottpoff(%rip), %r12/%rsp
* To:
* movq %fs:0, %r12/%rsp
* addq x@tpoff(%rax), %r12/%rsp
*
* Transition 2:
* movq x@gottpoff(%rip), %reg
* movq %fs:(%reg), %reg
* To:
* movq x@tpoff(%reg), %reg
* movq %fs:(%reg), %reg
*/
Conv_inv_buf_t inv_buf;
uint8_t reg; /* Register */
offset -= 3;
reg = offset[2] >> 3; /* Encoded dest. reg. operand */
DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
R_AMD64_TPOFF32, arsp, ld_reloc_sym_name));
arsp->rel_rtype = R_AMD64_TPOFF32;
arsp->rel_raddend = 0;
/*
* This is transition 2, and the special case of form 1 where
* a normal transition would index %rsp or %r12 and need a SIB
* byte in the leaq for which we lack space
*/
if ((offset[1] == INSN_MOVMR) ||
((offset[1] == INSN_ADDMR) && (reg == REG_ESP))) {
/*
* If we needed an extra bit of MOD.reg to refer to
* this register as the dest of the original movq we
* need an extra bit of MOD.rm to refer to it in the
* dest of the replacement movq or addq.
*/
if (offset[0] == REX_RW)
offset[0] = REX_BW;
offset[1] = (offset[1] == INSN_MOVMR) ?
INSN_MOVIR : INSN_ADDIR;
offset[2] = 0xc0 | reg;
return (FIX_RELOC);
} else if (offset[1] == INSN_ADDMR) {
/*
* If we needed an extra bit of MOD.reg to refer to
* this register in the dest of the addq we need an
* extra bit of both MOD.reg and MOD.rm to refer to it
* in the source and dest of the leaq
*/
if (offset[0] == REX_RW)
offset[0] = REX_BRW;
offset[1] = INSN_LEA;
offset[2] = 0x80 | (reg << 3) | reg;
return (FIX_RELOC);
}
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_BADTLSINS),
conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf),
arsp->rel_isdesc->is_file->ifl_name,
ld_reloc_sym_name(arsp),
arsp->rel_isdesc->is_name,
EC_OFF(arsp->rel_roffset));
return (FIX_ERROR);
}
case R_AMD64_TLSLD:
/*
* LD -> LE
*
* Transition
* 0x00 leaq x1@tlsgd(%rip), %rdi
* 0x07 call __tls_get_addr@plt
* 0x0c
* To:
* 0x00 .byte 0x66
* 0x01 .byte 0x66
* 0x02 .byte 0x66
* 0x03 movq %fs:0, %rax
*/
DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
R_AMD64_NONE, arsp, ld_reloc_sym_name));
offset -= 3;
(void) memcpy(offset, tlsinstr_ld_le, sizeof (tlsinstr_ld_le));
return (FIX_DONE);
case R_AMD64_DTPOFF32:
/*
* LD->LE
*
* Transition:
* 0x00 leaq x1@dtpoff(%rax), %rcx
* To:
* 0x00 leaq x1@tpoff(%rax), %rcx
*/
DBG_CALL(Dbg_reloc_transition(ofl->ofl_lml, M_MACH,
R_AMD64_TPOFF32, arsp, ld_reloc_sym_name));
arsp->rel_rtype = R_AMD64_TPOFF32;
arsp->rel_raddend = 0;
return (FIX_RELOC);
}
return (FIX_RELOC);
}
static uintptr_t
ld_do_activerelocs(Ofl_desc *ofl)
{
Rel_desc *arsp;
Rel_cachebuf *rcbp;
Aliste idx;
uintptr_t return_code = 1;
ofl_flag_t flags = ofl->ofl_flags;
if (aplist_nitems(ofl->ofl_actrels.rc_list) != 0)
DBG_CALL(Dbg_reloc_doact_title(ofl->ofl_lml));
/*
* Process active relocations.
*/
REL_CACHE_TRAVERSE(&ofl->ofl_actrels, idx, rcbp, arsp) {
uchar_t *addr;
Xword value;
Sym_desc *sdp;
const char *ifl_name;
Xword refaddr;
int moved = 0;
Gotref gref;
Os_desc *osp;
/*
* If the section this relocation is against has been discarded
* (-zignore), then discard (skip) the relocation itself.
*/
if ((arsp->rel_isdesc->is_flags & FLG_IS_DISCARD) &&
((arsp->rel_flags & (FLG_REL_GOT | FLG_REL_BSS |
FLG_REL_PLT | FLG_REL_NOINFO)) == 0)) {
DBG_CALL(Dbg_reloc_discard(ofl->ofl_lml, M_MACH, arsp));
continue;
}
/*
* We determine what the 'got reference' model (if required)
* is at this point. This needs to be done before tls_fixup()
* since it may 'transition' our instructions.
*
* The got table entries have already been assigned,
* and we bind to those initial entries.
*/
if (arsp->rel_flags & FLG_REL_DTLS)
gref = GOT_REF_TLSGD;
else if (arsp->rel_flags & FLG_REL_MTLS)
gref = GOT_REF_TLSLD;
else if (arsp->rel_flags & FLG_REL_STLS)
gref = GOT_REF_TLSIE;
else
gref = GOT_REF_GENERIC;
/*
* Perform any required TLS fixups.
*/
if (arsp->rel_flags & FLG_REL_TLSFIX) {
Fixupret ret;
if ((ret = tls_fixups(ofl, arsp)) == FIX_ERROR)
return (S_ERROR);
if (ret == FIX_DONE)
continue;
}
/*
* If this is a relocation against a move table, or
* expanded move table, adjust the relocation entries.
*/
if (RELAUX_GET_MOVE(arsp))
ld_adj_movereloc(ofl, arsp);
sdp = arsp->rel_sym;
refaddr = arsp->rel_roffset +
(Off)_elf_getxoff(arsp->rel_isdesc->is_indata);
if ((arsp->rel_flags & FLG_REL_CLVAL) ||
(arsp->rel_flags & FLG_REL_GOTCL))
value = 0;
else if (ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION) {
Sym_desc *sym;
/*
* The value for a symbol pointing to a SECTION
* is based off of that sections position.
*/
if ((sdp->sd_isc->is_flags & FLG_IS_RELUPD) &&
/* LINTED */
(sym = ld_am_I_partial(arsp, arsp->rel_raddend))) {
/*
* The symbol was moved, so adjust the value
* relative to the new section.
*/
value = sym->sd_sym->st_value;
moved = 1;
/*
* The original raddend covers the displacement
* from the section start to the desired
* address. The value computed above gets us
* from the section start to the start of the
* symbol range. Adjust the old raddend to
* remove the offset from section start to
* symbol start, leaving the displacement
* within the range of the symbol.
*/
arsp->rel_raddend -= sym->sd_osym->st_value;
} else {
value = _elf_getxoff(sdp->sd_isc->is_indata);
if (sdp->sd_isc->is_shdr->sh_flags & SHF_ALLOC)
value += sdp->sd_isc->is_osdesc->
os_shdr->sh_addr;
}
if (sdp->sd_isc->is_shdr->sh_flags & SHF_TLS)
value -= ofl->ofl_tlsphdr->p_vaddr;
} else if (IS_SIZE(arsp->rel_rtype)) {
/*
* Size relocations require the symbols size.
*/
value = sdp->sd_sym->st_size;
} else if ((sdp->sd_flags & FLG_SY_CAP) &&
sdp->sd_aux && sdp->sd_aux->sa_PLTndx) {
/*
* If relocation is against a capabilities symbol, we
* need to jump to an associated PLT, so that at runtime
* ld.so.1 is involved to determine the best binding
* choice. Otherwise, the value is the symbols value.
*/
value = ld_calc_plt_addr(sdp, ofl);
} else
value = sdp->sd_sym->st_value;
/*
* Relocation against the GLOBAL_OFFSET_TABLE.
*/
if ((arsp->rel_flags & FLG_REL_GOT) &&
!ld_reloc_set_aux_osdesc(ofl, arsp, ofl->ofl_osgot))
return (S_ERROR);
osp = RELAUX_GET_OSDESC(arsp);
/*
* If loadable and not producing a relocatable object add the
* sections virtual address to the reference address.
*/
if ((arsp->rel_flags & FLG_REL_LOAD) &&
((flags & FLG_OF_RELOBJ) == 0))
refaddr += arsp->rel_isdesc->is_osdesc->
os_shdr->sh_addr;
/*
* If this entry has a PLT assigned to it, its value is actually
* the address of the PLT (and not the address of the function).
*/
if (IS_PLT(arsp->rel_rtype)) {
if (sdp->sd_aux && sdp->sd_aux->sa_PLTndx)
value = ld_calc_plt_addr(sdp, ofl);
}
/*
* Add relocations addend to value. Add extra
* relocation addend if needed.
*
* Note: For GOT relative relocations on amd64 we discard the
* addend. It was relevant to the reference - not to the
* data item being referenced (ie: that -4 thing).
*/
if ((arsp->rel_flags & FLG_REL_GOT) == 0)
value += arsp->rel_raddend;
/*
* Determine whether the value needs further adjustment. Filter
* through the attributes of the relocation to determine what
* adjustment is required. Note, many of the following cases
* are only applicable when a .got is present. As a .got is
* not generated when a relocatable object is being built,
* any adjustments that require a .got need to be skipped.
*/
if ((arsp->rel_flags & FLG_REL_GOT) &&
((flags & FLG_OF_RELOBJ) == 0)) {
Xword R1addr;
uintptr_t R2addr;
Word gotndx;
Gotndx *gnp;
/*
* Perform relocation against GOT table. Since this
* doesn't fit exactly into a relocation we place the
* appropriate byte in the GOT directly
*
* Calculate offset into GOT at which to apply
* the relocation.
*/
gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
assert(gnp);
if (arsp->rel_rtype == R_AMD64_DTPOFF64)
gotndx = gnp->gn_gotndx + 1;
else
gotndx = gnp->gn_gotndx;
R1addr = (Xword)(gotndx * M_GOT_ENTSIZE);
/*
* Add the GOTs data's offset.
*/
R2addr = R1addr + (uintptr_t)osp->os_outdata->d_buf;
DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT,
M_MACH, SHT_RELA, arsp, R1addr, value,
ld_reloc_sym_name));
/*
* And do it.
*/
if (ofl->ofl_flags1 & FLG_OF1_ENCDIFF)
*(Xword *)R2addr = ld_bswap_Xword(value);
else
*(Xword *)R2addr = value;
continue;
} else if (IS_GOT_BASED(arsp->rel_rtype) &&
((flags & FLG_OF_RELOBJ) == 0)) {
value -= ofl->ofl_osgot->os_shdr->sh_addr;
} else if (IS_GOTPCREL(arsp->rel_rtype) &&
((flags & FLG_OF_RELOBJ) == 0)) {
Gotndx *gnp;
/*
* Calculation:
* G + GOT + A - P
*/
gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
assert(gnp);
value = (Xword)(ofl->ofl_osgot->os_shdr-> sh_addr) +
((Xword)gnp->gn_gotndx * M_GOT_ENTSIZE) +
arsp->rel_raddend - refaddr;
} else if (IS_GOT_PC(arsp->rel_rtype) &&
((flags & FLG_OF_RELOBJ) == 0)) {
value = (Xword)(ofl->ofl_osgot->os_shdr->
sh_addr) - refaddr + arsp->rel_raddend;
} else if ((IS_PC_RELATIVE(arsp->rel_rtype)) &&
(((flags & FLG_OF_RELOBJ) == 0) ||
(osp == sdp->sd_isc->is_osdesc))) {
value -= refaddr;
} else if (IS_TLS_INS(arsp->rel_rtype) &&
IS_GOT_RELATIVE(arsp->rel_rtype) &&
((flags & FLG_OF_RELOBJ) == 0)) {
Gotndx *gnp;
gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
assert(gnp);
value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE;
} else if (IS_GOT_RELATIVE(arsp->rel_rtype) &&
((flags & FLG_OF_RELOBJ) == 0)) {
Gotndx *gnp;
gnp = ld_find_got_ndx(sdp->sd_GOTndxs, gref, ofl, arsp);
assert(gnp);
value = (Xword)gnp->gn_gotndx * M_GOT_ENTSIZE;
} else if ((arsp->rel_flags & FLG_REL_STLS) &&
((flags & FLG_OF_RELOBJ) == 0)) {
Xword tlsstatsize;
/*
* This is the LE TLS reference model. Static
* offset is hard-coded.
*/
tlsstatsize = S_ROUND(ofl->ofl_tlsphdr->p_memsz,
M_TLSSTATALIGN);
value = tlsstatsize - value;
/*
* Since this code is fixed up, it assumes a negative
* offset that can be added to the thread pointer.
*/
if (arsp->rel_rtype == R_AMD64_TPOFF32)
value = -value;
}
if (arsp->rel_isdesc->is_file)
ifl_name = arsp->rel_isdesc->is_file->ifl_name;
else
ifl_name = MSG_INTL(MSG_STR_NULL);
/*
* Make sure we have data to relocate. Compiler and assembler
* developers have been known to generate relocations against
* invalid sections (normally .bss), so for their benefit give
* them sufficient information to help analyze the problem.
* End users should never see this.
*/
if (arsp->rel_isdesc->is_indata->d_buf == 0) {
Conv_inv_buf_t inv_buf;
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_REL_EMPTYSEC),
conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf),
ifl_name, ld_reloc_sym_name(arsp),
EC_WORD(arsp->rel_isdesc->is_scnndx),
arsp->rel_isdesc->is_name);
return (S_ERROR);
}
/*
* Get the address of the data item we need to modify.
*/
addr = (uchar_t *)((uintptr_t)arsp->rel_roffset +
(uintptr_t)_elf_getxoff(arsp->rel_isdesc->is_indata));
DBG_CALL(Dbg_reloc_doact(ofl->ofl_lml, ELF_DBG_LD_ACT,
M_MACH, SHT_RELA, arsp, EC_NATPTR(addr), value,
ld_reloc_sym_name));
addr += (uintptr_t)osp->os_outdata->d_buf;
if ((((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) >
ofl->ofl_size) || (arsp->rel_roffset >
osp->os_shdr->sh_size)) {
int class;
Conv_inv_buf_t inv_buf;
if (((uintptr_t)addr - (uintptr_t)ofl->ofl_nehdr) >
ofl->ofl_size)
class = ERR_FATAL;
else
class = ERR_WARNING;
ld_eprintf(ofl, class, MSG_INTL(MSG_REL_INVALOFFSET),
conv_reloc_amd64_type(arsp->rel_rtype, 0, &inv_buf),
ifl_name, EC_WORD(arsp->rel_isdesc->is_scnndx),
arsp->rel_isdesc->is_name, ld_reloc_sym_name(arsp),
EC_ADDR((uintptr_t)addr -
(uintptr_t)ofl->ofl_nehdr));
if (class == ERR_FATAL) {
return_code = S_ERROR;
continue;
}
}
/*
* The relocation is additive. Ignore the previous symbol
* value if this local partial symbol is expanded.
*/
if (moved)
value -= *addr;
/*
* If '-z noreloc' is specified - skip the do_reloc_ld stage.
*/
if (OFL_DO_RELOC(ofl)) {
/*
* If this is a PROGBITS section and the running linker
* has a different byte order than the target host,
* tell do_reloc_ld() to swap bytes.
*/
if (do_reloc_ld(arsp, addr, &value, ld_reloc_sym_name,
ifl_name, OFL_SWAP_RELOC_DATA(ofl, arsp),
ofl->ofl_lml) == 0) {
ofl->ofl_flags |= FLG_OF_FATAL;
return_code = S_ERROR;
}
}
}
return (return_code);
}
static uintptr_t
ld_add_outrel(Word flags, Rel_desc *rsp, Ofl_desc *ofl)
{
Rel_desc *orsp;
Sym_desc *sdp = rsp->rel_sym;
/*
* Static executables *do not* want any relocations against them.
* Since our engine still creates relocations against a WEAK UNDEFINED
* symbol in a static executable, it's best to disable them here
* instead of through out the relocation code.
*/
if (OFL_IS_STATIC_EXEC(ofl))
return (1);
/*
* If we are adding a output relocation against a section
* symbol (non-RELATIVE) then mark that section. These sections
* will be added to the .dynsym symbol table.
*/
if (sdp && (rsp->rel_rtype != M_R_RELATIVE) &&
((flags & FLG_REL_SCNNDX) ||
(ELF_ST_TYPE(sdp->sd_sym->st_info) == STT_SECTION))) {
/*
* If this is a COMMON symbol - no output section
* exists yet - (it's created as part of sym_validate()).
* So - we mark here that when it's created it should
* be tagged with the FLG_OS_OUTREL flag.
*/
if ((sdp->sd_flags & FLG_SY_SPECSEC) &&
(sdp->sd_sym->st_shndx == SHN_COMMON)) {
if (ELF_ST_TYPE(sdp->sd_sym->st_info) != STT_TLS)
ofl->ofl_flags1 |= FLG_OF1_BSSOREL;
else
ofl->ofl_flags1 |= FLG_OF1_TLSOREL;
} else {
Os_desc *osp;
Is_desc *isp = sdp->sd_isc;
if (isp && ((osp = isp->is_osdesc) != NULL) &&
((osp->os_flags & FLG_OS_OUTREL) == 0)) {
ofl->ofl_dynshdrcnt++;
osp->os_flags |= FLG_OS_OUTREL;
}
}
}
/* Enter it into the output relocation cache */
if ((orsp = ld_reloc_enter(ofl, &ofl->ofl_outrels, rsp, flags)) == NULL)
return (S_ERROR);
if (flags & FLG_REL_GOT)
ofl->ofl_relocgotsz += (Xword)sizeof (Rela);
else if (flags & FLG_REL_PLT)
ofl->ofl_relocpltsz += (Xword)sizeof (Rela);
else if (flags & FLG_REL_BSS)
ofl->ofl_relocbsssz += (Xword)sizeof (Rela);
else if (flags & FLG_REL_NOINFO)
ofl->ofl_relocrelsz += (Xword)sizeof (Rela);
else
RELAUX_GET_OSDESC(orsp)->os_szoutrels += (Xword)sizeof (Rela);
if (orsp->rel_rtype == M_R_RELATIVE)
ofl->ofl_relocrelcnt++;
/*
* We don't perform sorting on PLT relocations because
* they have already been assigned a PLT index and if we
* were to sort them we would have to re-assign the plt indexes.
*/
if (!(flags & FLG_REL_PLT))
ofl->ofl_reloccnt++;
/*
* Insure a GLOBAL_OFFSET_TABLE is generated if required.
*/
if (IS_GOT_REQUIRED(orsp->rel_rtype))
ofl->ofl_flags |= FLG_OF_BLDGOT;
/*
* Identify and possibly warn of a displacement relocation.
*/
if (orsp->rel_flags & FLG_REL_DISP) {
ofl->ofl_dtflags_1 |= DF_1_DISPRELPND;
if (ofl->ofl_flags & FLG_OF_VERBOSE)
ld_disp_errmsg(MSG_INTL(MSG_REL_DISPREL4), orsp, ofl);
}
DBG_CALL(Dbg_reloc_ors_entry(ofl->ofl_lml, ELF_DBG_LD, SHT_RELA,
M_MACH, orsp));
return (1);
}
/*
* process relocation for a LOCAL symbol
*/
static uintptr_t
ld_reloc_local(Rel_desc * rsp, Ofl_desc * ofl)
{
ofl_flag_t flags = ofl->ofl_flags;
Sym_desc *sdp = rsp->rel_sym;
Word shndx = sdp->sd_sym->st_shndx;
Word ortype = rsp->rel_rtype;
/*
* if ((shared object) and (not pc relative relocation) and
* (not against ABS symbol))
* then
* build R_AMD64_RELATIVE
* fi
*/
if ((flags & FLG_OF_SHAROBJ) && (rsp->rel_flags & FLG_REL_LOAD) &&
!(IS_PC_RELATIVE(rsp->rel_rtype)) && !(IS_SIZE(rsp->rel_rtype)) &&
!(IS_GOT_BASED(rsp->rel_rtype)) &&
!(rsp->rel_isdesc != NULL &&
(rsp->rel_isdesc->is_shdr->sh_type == SHT_SUNW_dof)) &&
(((sdp->sd_flags & FLG_SY_SPECSEC) == 0) ||
(shndx != SHN_ABS) || (sdp->sd_aux && sdp->sd_aux->sa_symspec))) {
/*
* R_AMD64_RELATIVE updates a 64bit address, if this
* relocation isn't a 64bit binding then we can not
* simplify it to a RELATIVE relocation.
*/
if (reloc_table[ortype].re_fsize != sizeof (Addr)) {
return (ld_add_outrel(0, rsp, ofl));
}
rsp->rel_rtype = R_AMD64_RELATIVE;
if (ld_add_outrel(FLG_REL_ADVAL, rsp, ofl) == S_ERROR)
return (S_ERROR);
rsp->rel_rtype = ortype;
return (1);
}
/*
* If the relocation is against a 'non-allocatable' section
* and we can not resolve it now - then give a warning
* message.
*
* We can not resolve the symbol if either:
* a) it's undefined
* b) it's defined in a shared library and a
* COPY relocation hasn't moved it to the executable
*
* Note: because we process all of the relocations against the
* text segment before any others - we know whether
* or not a copy relocation will be generated before
* we get here (see reloc_init()->reloc_segments()).
*/
if (!(rsp->rel_flags & FLG_REL_LOAD) &&
((shndx == SHN_UNDEF) ||
((sdp->sd_ref == REF_DYN_NEED) &&
((sdp->sd_flags & FLG_SY_MVTOCOMM) == 0)))) {
Conv_inv_buf_t inv_buf;
Os_desc *osp = RELAUX_GET_OSDESC(rsp);
/*
* If the relocation is against a SHT_SUNW_ANNOTATE
* section - then silently ignore that the relocation
* can not be resolved.
*/
if (osp && (osp->os_shdr->sh_type == SHT_SUNW_ANNOTATE))
return (0);
ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_REL_EXTERNSYM),
conv_reloc_amd64_type(rsp->rel_rtype, 0, &inv_buf),
rsp->rel_isdesc->is_file->ifl_name,
ld_reloc_sym_name(rsp), osp->os_name);
return (1);
}
/*
* Perform relocation.
*/
return (ld_add_actrel(NULL, rsp, ofl));
}
static uintptr_t
ld_reloc_TLS(Boolean local, Rel_desc * rsp, Ofl_desc * ofl)
{
Word rtype = rsp->rel_rtype;
Sym_desc *sdp = rsp->rel_sym;
ofl_flag_t flags = ofl->ofl_flags;
Gotndx *gnp;
/*
* If we're building an executable - use either the IE or LE access
* model. If we're building a shared object process any IE model.
*/
if ((flags & FLG_OF_EXEC) || (IS_TLS_IE(rtype))) {
/*
* Set the DF_STATIC_TLS flag.
*/
ofl->ofl_dtflags |= DF_STATIC_TLS;
if (!local || ((flags & FLG_OF_EXEC) == 0)) {
/*
* Assign a GOT entry for static TLS references.
*/
if ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs,
GOT_REF_TLSIE, ofl, rsp)) == NULL) {
if (ld_assign_got_TLS(local, rsp, ofl, sdp,
gnp, GOT_REF_TLSIE, FLG_REL_STLS,
rtype, R_AMD64_TPOFF64, 0) == S_ERROR)
return (S_ERROR);
}
/*
* IE access model.
*/
if (IS_TLS_IE(rtype))
return (ld_add_actrel(FLG_REL_STLS, rsp, ofl));
/*
* Fixups are required for other executable models.
*/
return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS),
rsp, ofl));
}
/*
* LE access model.
*/
if (IS_TLS_LE(rtype))
return (ld_add_actrel(FLG_REL_STLS, rsp, ofl));
return (ld_add_actrel((FLG_REL_TLSFIX | FLG_REL_STLS),
rsp, ofl));
}
/*
* Building a shared object.
*
* Assign a GOT entry for a dynamic TLS reference.
*/
if (IS_TLS_LD(rtype) && ((gnp = ld_find_got_ndx(sdp->sd_GOTndxs,
GOT_REF_TLSLD, ofl, rsp)) == NULL)) {
if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSLD,
FLG_REL_MTLS, rtype, R_AMD64_DTPMOD64, NULL) == S_ERROR)
return (S_ERROR);
} else if (IS_TLS_GD(rtype) &&
((gnp = ld_find_got_ndx(sdp->sd_GOTndxs, GOT_REF_TLSGD,
ofl, rsp)) == NULL)) {
if (ld_assign_got_TLS(local, rsp, ofl, sdp, gnp, GOT_REF_TLSGD,
FLG_REL_DTLS, rtype, R_AMD64_DTPMOD64,
R_AMD64_DTPOFF64) == S_ERROR)
return (S_ERROR);
}
if (IS_TLS_LD(rtype))
return (ld_add_actrel(FLG_REL_MTLS, rsp, ofl));
return (ld_add_actrel(FLG_REL_DTLS, rsp, ofl));
}
/* ARGSUSED5 */
static uintptr_t
ld_assign_got_ndx(Alist **alpp, Gotndx *pgnp, Gotref gref, Ofl_desc *ofl,
Rel_desc *rsp, Sym_desc *sdp)
{
Xword raddend;
Gotndx gn, *gnp;
Aliste idx;
uint_t gotents;
raddend = rsp->rel_raddend;
if (pgnp && (pgnp->gn_addend == raddend) && (pgnp->gn_gotref == gref))
return (1);
if ((gref == GOT_REF_TLSGD) || (gref == GOT_REF_TLSLD))
gotents = 2;
else
gotents = 1;
gn.gn_addend = raddend;
gn.gn_gotndx = ofl->ofl_gotcnt;
gn.gn_gotref = gref;
ofl->ofl_gotcnt += gotents;
if (gref == GOT_REF_TLSLD) {
if (ofl->ofl_tlsldgotndx == NULL) {
if ((gnp = libld_malloc(sizeof (Gotndx))) == NULL)
return (S_ERROR);
(void) memcpy(gnp, &gn, sizeof (Gotndx));
ofl->ofl_tlsldgotndx = gnp;
}
return (1);
}
idx = 0;
for (ALIST_TRAVERSE(*alpp, idx, gnp)) {
if (gnp->gn_addend > raddend)
break;
}
/*
* GOT indexes are maintained on an Alist, where there is typically
* only one index. The usage of this list is to scan the list to find
* an index, and then apply that index immediately to a relocation.
* Thus there are no external references to these GOT index structures
* that can be compromised by the Alist being reallocated.
*/
if (alist_insert(alpp, &gn, sizeof (Gotndx),
AL_CNT_SDP_GOT, idx) == NULL)
return (S_ERROR);
return (1);
}
static void
ld_assign_plt_ndx(Sym_desc * sdp, Ofl_desc *ofl)
{
sdp->sd_aux->sa_PLTndx = 1 + ofl->ofl_pltcnt++;
sdp->sd_aux->sa_PLTGOTndx = ofl->ofl_gotcnt++;
ofl->ofl_flags |= FLG_OF_BLDGOT;
}
static uchar_t plt0_template[M_PLT_ENTSIZE] = {
/* 0x00 PUSHQ GOT+8(%rip) */ 0xff, 0x35, 0x00, 0x00, 0x00, 0x00,
/* 0x06 JMP *GOT+16(%rip) */ 0xff, 0x25, 0x00, 0x00, 0x00, 0x00,
/* 0x0c NOP */ 0x90,
/* 0x0d NOP */ 0x90,
/* 0x0e NOP */ 0x90,
/* 0x0f NOP */ 0x90
};
/*
* Initializes .got[0] with the _DYNAMIC symbol value.
*/
static uintptr_t
ld_fillin_gotplt(Ofl_desc *ofl)
{
int bswap = (ofl->ofl_flags1 & FLG_OF1_ENCDIFF) != 0;
if (ofl->ofl_osgot) {
Sym_desc *sdp;
if ((sdp = ld_sym_find(MSG_ORIG(MSG_SYM_DYNAMIC_U),
SYM_NOHASH, NULL, ofl)) != NULL) {
uchar_t *genptr;
genptr = ((uchar_t *)ofl->ofl_osgot->os_outdata->d_buf +
(M_GOT_XDYNAMIC * M_GOT_ENTSIZE));
/* LINTED */
*(Xword *)genptr = sdp->sd_sym->st_value;
if (bswap)
/* LINTED */
*(Xword *)genptr =
/* LINTED */
ld_bswap_Xword(*(Xword *)genptr);
}
}
/*
* Fill in the reserved slot in the procedure linkage table the first
* entry is:
* 0x00 PUSHQ GOT+8(%rip) # GOT[1]
* 0x06 JMP *GOT+16(%rip) # GOT[2]
* 0x0c NOP
* 0x0d NOP
* 0x0e NOP
* 0x0f NOP
*/
if ((ofl->ofl_flags & FLG_OF_DYNAMIC) && ofl->ofl_osplt) {
uchar_t *pltent;
Xword val1;
pltent = (uchar_t *)ofl->ofl_osplt->os_outdata->d_buf;
bcopy(plt0_template, pltent, sizeof (plt0_template));
/*
* If '-z noreloc' is specified - skip the do_reloc_ld
* stage.
*/
if (!OFL_DO_RELOC(ofl))
return (1);
/*
* filin:
* PUSHQ GOT + 8(%rip)
*
* Note: 0x06 below represents the offset to the
* next instruction - which is what %rip will
* be pointing at.
*/
val1 = (ofl->ofl_osgot->os_shdr->sh_addr) +
(M_GOT_XLINKMAP * M_GOT_ENTSIZE) -
ofl->ofl_osplt->os_shdr->sh_addr - 0x06;
if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x02],
&val1, syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT),
bswap, ofl->ofl_lml) == 0) {
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLT0FAIL));
return (S_ERROR);
}
/*
* filin:
* JMP *GOT+16(%rip)
*/
val1 = (ofl->ofl_osgot->os_shdr->sh_addr) +
(M_GOT_XRTLD * M_GOT_ENTSIZE) -
ofl->ofl_osplt->os_shdr->sh_addr - 0x0c;
if (do_reloc_ld(&rdesc_r_amd64_gotpcrel, &pltent[0x08],
&val1, syn_rdesc_sym_name, MSG_ORIG(MSG_SPECFIL_PLTENT),
bswap, ofl->ofl_lml) == 0) {
ld_eprintf(ofl, ERR_FATAL, MSG_INTL(MSG_PLT_PLT0FAIL));
return (S_ERROR);
}
}
return (1);
}
/*
* Template for generating "void (*)(void)" function
*/
static const uchar_t nullfunc_tmpl[] = { /* amd64 */
/* 0x00 */ 0x55, /* pushq %rbp */
/* 0x01 */ 0x48, 0x8b, 0xec, /* movq %rsp,%rbp */
/* 0x04 */ 0x48, 0x8b, 0xe5, /* movq %rbp,%rsp */
/* 0x07 */ 0x5d, /* popq %rbp */
/* 0x08 */ 0xc3 /* ret */
};
/*
* Function used to provide fill padding in SHF_EXECINSTR sections
*
* entry:
*
* base - base address of section being filled
* offset - starting offset for fill within memory referenced by base
* cnt - # bytes to be filled
*
* exit:
* The fill has been completed.
*/
static void
execfill(void *base, off_t off, size_t cnt)
{
/*
* 0x90 is an X86 NOP instruction in both 32 and 64-bit worlds.
* There are no alignment constraints.
*/
(void) memset(off + (char *)base, 0x90, cnt);
}
/*
* Return the ld_targ definition for this target.
*/
const Target *
ld_targ_init_x86(void)
{
static const Target _ld_targ = {
{ /* Target_mach */
M_MACH, /* m_mach */
M_MACHPLUS, /* m_machplus */
M_FLAGSPLUS, /* m_flagsplus */
M_CLASS, /* m_class */
M_DATA, /* m_data */
M_SEGM_ALIGN, /* m_segm_align */
M_SEGM_ORIGIN, /* m_segm_origin */
M_SEGM_AORIGIN, /* m_segm_aorigin */
M_DATASEG_PERM, /* m_dataseg_perm */
M_STACK_PERM, /* m_stack_perm */
M_WORD_ALIGN, /* m_word_align */
MSG_ORIG(MSG_PTH_RTLD_AMD64), /* m_def_interp */
/* Relocation type codes */
M_R_ARRAYADDR, /* m_r_arrayaddr */
M_R_COPY, /* m_r_copy */
M_R_GLOB_DAT, /* m_r_glob_dat */
M_R_JMP_SLOT, /* m_r_jmp_slot */
M_R_NUM, /* m_r_num */
M_R_NONE, /* m_r_none */
M_R_RELATIVE, /* m_r_relative */
M_R_REGISTER, /* m_r_register */
/* Relocation related constants */
M_REL_DT_COUNT, /* m_rel_dt_count */
M_REL_DT_ENT, /* m_rel_dt_ent */
M_REL_DT_SIZE, /* m_rel_dt_size */
M_REL_DT_TYPE, /* m_rel_dt_type */
M_REL_SHT_TYPE, /* m_rel_sht_type */
/* GOT related constants */
M_GOT_ENTSIZE, /* m_got_entsize */
M_GOT_XNumber, /* m_got_xnumber */
/* PLT related constants */
M_PLT_ALIGN, /* m_plt_align */
M_PLT_ENTSIZE, /* m_plt_entsize */
M_PLT_RESERVSZ, /* m_plt_reservsz */
M_PLT_SHF_FLAGS, /* m_plt_shf_flags */
/* Section type of .eh_frame/.eh_frame_hdr sections */
SHT_AMD64_UNWIND, /* m_sht_unwind */
M_DT_REGISTER, /* m_dt_register */
},
{ /* Target_machid */
M_ID_ARRAY, /* id_array */
M_ID_BSS, /* id_bss */
M_ID_CAP, /* id_cap */
M_ID_CAPINFO, /* id_capinfo */
M_ID_CAPCHAIN, /* id_capchain */
M_ID_DATA, /* id_data */
M_ID_DYNAMIC, /* id_dynamic */
M_ID_DYNSORT, /* id_dynsort */
M_ID_DYNSTR, /* id_dynstr */
M_ID_DYNSYM, /* id_dynsym */
M_ID_DYNSYM_NDX, /* id_dynsym_ndx */
M_ID_GOT, /* id_got */
M_ID_UNKNOWN, /* id_gotdata (unused) */
M_ID_HASH, /* id_hash */
M_ID_INTERP, /* id_interp */
M_ID_LBSS, /* id_lbss */
M_ID_LDYNSYM, /* id_ldynsym */
M_ID_NOTE, /* id_note */
M_ID_NULL, /* id_null */
M_ID_PLT, /* id_plt */
M_ID_REL, /* id_rel */
M_ID_STRTAB, /* id_strtab */
M_ID_SYMINFO, /* id_syminfo */
M_ID_SYMTAB, /* id_symtab */
M_ID_SYMTAB_NDX, /* id_symtab_ndx */
M_ID_TEXT, /* id_text */
M_ID_TLS, /* id_tls */
M_ID_TLSBSS, /* id_tlsbss */
M_ID_UNKNOWN, /* id_unknown */
M_ID_UNWIND, /* id_unwind */
M_ID_UNWINDHDR, /* id_unwindhdr */
M_ID_USER, /* id_user */
M_ID_VERSION, /* id_version */
},
{ /* Target_nullfunc */
nullfunc_tmpl, /* nf_template */
sizeof (nullfunc_tmpl), /* nf_size */
},
{ /* Target_fillfunc */
execfill /* ff_execfill */
},
{ /* Target_machrel */
reloc_table,
ld_init_rel, /* mr_init_rel */
ld_mach_eflags, /* mr_mach_eflags */
ld_mach_make_dynamic, /* mr_mach_make_dynamic */
ld_mach_update_odynamic, /* mr_mach_update_odynamic */
ld_calc_plt_addr, /* mr_calc_plt_addr */
ld_perform_outreloc, /* mr_perform_outreloc */
ld_do_activerelocs, /* mr_do_activerelocs */
ld_add_outrel, /* mr_add_outrel */
NULL, /* mr_reloc_register */
ld_reloc_local, /* mr_reloc_local */
NULL, /* mr_reloc_GOTOP */
ld_reloc_TLS, /* mr_reloc_TLS */
NULL, /* mr_assign_got */
ld_find_got_ndx, /* mr_find_got_ndx */
ld_calc_got_offset, /* mr_calc_got_offset */
ld_assign_got_ndx, /* mr_assign_got_ndx */
ld_assign_plt_ndx, /* mr_assign_plt_ndx */
NULL, /* mr_allocate_got */
ld_fillin_gotplt, /* mr_fillin_gotplt */
},
{ /* Target_machsym */
NULL, /* ms_reg_check */
NULL, /* ms_mach_sym_typecheck */
NULL, /* ms_is_regsym */
NULL, /* ms_reg_find */
NULL /* ms_reg_enter */
}
};
return (&_ld_targ);
}