glibc/sysdeps/i386/dl-trampoline.S
Fangrui Song bf433b849a elf: Remove Intel MPX support (lazy PLT, ld.so profile, and LD_AUDIT)
Intel MPX failed to gain wide adoption and has been deprecated for a
while. GCC 9.1 removed Intel MPX support. Linux kernel removed MPX in
2019.

This patch removes the support code from the dynamic loader.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-10-11 11:14:02 -07:00

267 lines
7.1 KiB
ArmAsm

/* PLT trampolines. i386 version.
Copyright (C) 2004-2021 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
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <link-defines.h>
.text
.globl _dl_runtime_resolve
.type _dl_runtime_resolve, @function
cfi_startproc
.align 16
_dl_runtime_resolve:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %edx
cfi_adjust_cfa_offset (4)
movl 16(%esp), %edx # Copy args pushed by PLT in register. Note
movl 12(%esp), %eax # that `fixup' takes its parameters in regs.
call _dl_fixup # Call resolver.
popl %edx # Get register content back.
cfi_adjust_cfa_offset (-4)
movl (%esp), %ecx
movl %eax, (%esp) # Store the function address.
movl 4(%esp), %eax
ret $12 # Jump to function address.
cfi_endproc
.size _dl_runtime_resolve, .-_dl_runtime_resolve
# The SHSTK compatible version.
.text
.globl _dl_runtime_resolve_shstk
.type _dl_runtime_resolve_shstk, @function
cfi_startproc
.align 16
_dl_runtime_resolve_shstk:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %edx
cfi_adjust_cfa_offset (4)
movl 12(%esp), %edx # Copy args pushed by PLT in register. Note
movl 8(%esp), %eax # that `fixup' takes its parameters in regs.
call _dl_fixup # Call resolver.
movl (%esp), %edx # Get register content back.
movl %eax, %ecx # Store the function address.
movl 4(%esp), %eax # Get register content back.
addl $16, %esp # Adjust stack: PLT1 + PLT2 + %eax + %edx
cfi_adjust_cfa_offset (-16)
jmp *%ecx # Jump to function address.
cfi_endproc
.size _dl_runtime_resolve_shstk, .-_dl_runtime_resolve_shstk
#ifndef PROF
# The SHSTK compatible version.
.globl _dl_runtime_profile_shstk
.type _dl_runtime_profile_shstk, @function
cfi_startproc
.align 16
_dl_runtime_profile_shstk:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %esp
cfi_adjust_cfa_offset (4)
addl $8, (%esp) # Account for the pushed PLT data
pushl %ebp
cfi_adjust_cfa_offset (4)
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %edx
cfi_adjust_cfa_offset (4)
movl %esp, %ecx
subl $8, %esp
cfi_adjust_cfa_offset (8)
movl $-1, 4(%esp)
leal 4(%esp), %edx
movl %edx, (%esp)
pushl %ecx # Address of the register structure
cfi_adjust_cfa_offset (4)
movl 40(%esp), %ecx # Load return address
movl 36(%esp), %edx # Copy args pushed by PLT in register. Note
movl 32(%esp), %eax # that `fixup' takes its parameters in regs.
call _dl_profile_fixup # Call resolver.
cfi_adjust_cfa_offset (-8)
movl (%esp), %edx
testl %edx, %edx
jns 1f
movl 4(%esp), %edx # Get register content back.
movl %eax, %ecx # Store the function address.
movl 12(%esp), %eax # Get register content back.
# Adjust stack: PLT1 + PLT2 + %esp + %ebp + %eax + %ecx + %edx
# + free.
addl $32, %esp
cfi_adjust_cfa_offset (-32)
jmp *%ecx # Jump to function address.
cfi_endproc
.size _dl_runtime_profile_shstk, .-_dl_runtime_profile_shstk
.globl _dl_runtime_profile
.type _dl_runtime_profile, @function
cfi_startproc
.align 16
_dl_runtime_profile:
cfi_adjust_cfa_offset (8)
_CET_ENDBR
pushl %esp
cfi_adjust_cfa_offset (4)
addl $8, (%esp) # Account for the pushed PLT data
pushl %ebp
cfi_adjust_cfa_offset (4)
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %edx
cfi_adjust_cfa_offset (4)
movl %esp, %ecx
subl $8, %esp
cfi_adjust_cfa_offset (8)
movl $-1, 4(%esp)
leal 4(%esp), %edx
movl %edx, (%esp)
pushl %ecx # Address of the register structure
cfi_adjust_cfa_offset (4)
movl 40(%esp), %ecx # Load return address
movl 36(%esp), %edx # Copy args pushed by PLT in register. Note
movl 32(%esp), %eax # that `fixup' takes its parameters in regs.
call _dl_profile_fixup # Call resolver.
cfi_adjust_cfa_offset (-8)
movl (%esp), %edx
testl %edx, %edx
jns 1f
popl %edx
cfi_adjust_cfa_offset (-4)
popl %edx # Get register content back.
cfi_adjust_cfa_offset (-4)
movl (%esp), %ecx
movl %eax, (%esp) # Store the function address.
movl 4(%esp), %eax
ret $20 # Jump to function address.
/*
+32 return address
+28 PLT1
+24 PLT2
+20 %esp
+16 %ebp
+12 %eax
+8 %ecx
+4 %edx
%esp free
*/
cfi_adjust_cfa_offset (8)
1: movl %ebx, (%esp)
cfi_rel_offset (ebx, 0)
movl %edx, %ebx # This is the frame buffer size
pushl %edi
cfi_adjust_cfa_offset (4)
cfi_rel_offset (edi, 0)
pushl %esi
cfi_adjust_cfa_offset (4)
cfi_rel_offset (esi, 0)
leal 44(%esp), %esi
movl %ebx, %ecx
orl $4, %ebx # Increase frame size if necessary to align
# stack for the function call
andl $~3, %ebx
movl %esp, %edi
subl %ebx, %edi
movl %esp, %ebx
cfi_def_cfa_register (ebx)
movl %edi, %esp
shrl $2, %ecx
rep
movsl
movl (%ebx), %esi
cfi_restore (esi)
movl 4(%ebx), %edi
cfi_restore (edi)
/*
%ebx+40 return address
%ebx+36 PLT1
%ebx+32 PLT2
%ebx+28 %esp
%ebx+24 %ebp
%ebx+20 %eax
%ebx+16 %ecx
%ebx+12 %edx
%ebx+8 %ebx
%ebx+4 free
%ebx free
%esp copied stack frame
*/
movl %eax, (%ebx)
movl 12(%ebx), %edx
movl 16(%ebx), %ecx
movl 20(%ebx), %eax
call *(%ebx)
movl %ebx, %esp
cfi_def_cfa_register (esp)
movl 8(%esp), %ebx
cfi_restore (ebx)
/*
+40 return address
+36 PLT1
+32 PLT2
+28 %esp
+24 %ebp
+20 %eax
+16 %ecx
+12 %edx
+8 free
+4 free
%esp free
*/
#if LONG_DOUBLE_SIZE != 12
# error "long double size must be 12 bytes"
#endif
# Allocate space for La_i86_retval and subtract 12 free bytes.
subl $(LRV_SIZE - 12), %esp
cfi_adjust_cfa_offset (LRV_SIZE - 12)
movl %eax, LRV_EAX_OFFSET(%esp)
movl %edx, LRV_EDX_OFFSET(%esp)
fstpt LRV_ST0_OFFSET(%esp)
fstpt LRV_ST1_OFFSET(%esp)
pushl %esp
cfi_adjust_cfa_offset (4)
# Address of La_i86_regs area.
leal (LRV_SIZE + 4)(%esp), %ecx
# PLT2
movl (LRV_SIZE + 4 + LR_SIZE)(%esp), %eax
# PLT1
movl (LRV_SIZE + 4 + LR_SIZE + 4)(%esp), %edx
call _dl_call_pltexit
movl LRV_EAX_OFFSET(%esp), %eax
movl LRV_EDX_OFFSET(%esp), %edx
fldt LRV_ST1_OFFSET(%esp)
fldt LRV_ST0_OFFSET(%esp)
# Restore stack before return.
addl $(LRV_SIZE + 4 + LR_SIZE + 4), %esp
cfi_adjust_cfa_offset (-(LRV_SIZE + 4 + LR_SIZE + 4))
ret
cfi_endproc
.size _dl_runtime_profile, .-_dl_runtime_profile
#endif