glibc/sysdeps/x86_64/setjmp.S
H.J. Lu faaee1f07e x86: Support shadow stack pointer in setjmp/longjmp
Save and restore shadow stack pointer in setjmp and longjmp to support
shadow stack in Intel CET.  Use feature_1 in tcbhead_t to check if
shadow stack is enabled before saving and restoring shadow stack pointer.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

	* sysdeps/i386/__longjmp.S: Include <jmp_buf-ssp.h>.
	(__longjmp): Restore shadow stack pointer if shadow stack is
	enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp
	isn't defined for __longjmp_cancel.
	* sysdeps/i386/bsd-_setjmp.S: Include <jmp_buf-ssp.h>.
	(_setjmp): Save shadow stack pointer if shadow stack is enabled
	and SHADOW_STACK_POINTER_OFFSET is defined.
	* sysdeps/i386/bsd-setjmp.S: Include <jmp_buf-ssp.h>.
	(setjmp): Save shadow stack pointer if shadow stack is enabled
	and SHADOW_STACK_POINTER_OFFSET is defined.
	* sysdeps/i386/setjmp.S: Include <jmp_buf-ssp.h>.
	(__sigsetjmp): Save shadow stack pointer if shadow stack is
	enabled and SHADOW_STACK_POINTER_OFFSET is defined.
	* sysdeps/unix/sysv/linux/i386/____longjmp_chk.S: Include
	<jmp_buf-ssp.h>.
	(____longjmp_chk): Restore shadow stack pointer if shadow stack
	is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
	* sysdeps/unix/sysv/linux/x86/Makefile (gen-as-const-headers):
	Remove jmp_buf-ssp.sym.
	* sysdeps/unix/sysv/linux/x86_64/____longjmp_chk.S: Include
	<jmp_buf-ssp.h>.
	(____longjmp_chk): Restore shadow stack pointer if shadow stack
	is enabled and SHADOW_STACK_POINTER_OFFSET is defined.
	* sysdeps/x86/Makefile (gen-as-const-headers): Add
	jmp_buf-ssp.sym.
	* sysdeps/x86/jmp_buf-ssp.sym: New dummy file.
	* sysdeps/x86_64/__longjmp.S: Include <jmp_buf-ssp.h>.
	(__longjmp): Restore shadow stack pointer if shadow stack is
	enabled, SHADOW_STACK_POINTER_OFFSET is defined and __longjmp
	isn't defined for __longjmp_cancel.
	* sysdeps/x86_64/setjmp.S: Include <jmp_buf-ssp.h>.
	(__sigsetjmp): Save shadow stack pointer if shadow stack is
	enabled and SHADOW_STACK_POINTER_OFFSET is defined.
2018-07-14 05:59:53 -07:00

88 lines
2.7 KiB
ArmAsm

/* setjmp for x86-64.
Copyright (C) 2001-2018 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/>. */
#include <sysdep.h>
#include <jmpbuf-offsets.h>
#include <jmp_buf-ssp.h>
#include <asm-syntax.h>
#include <stap-probe.h>
/* Don't save shadow stack register if shadow stack isn't enabled. */
#if !SHSTK_ENABLED
# undef SHADOW_STACK_POINTER_OFFSET
#endif
ENTRY (__sigsetjmp)
/* Save registers. */
movq %rbx, (JB_RBX*8)(%rdi)
#ifdef PTR_MANGLE
# ifdef __ILP32__
/* Save the high bits of %rbp first, since PTR_MANGLE will
only handle the low bits but we cannot presume %rbp is
being used as a pointer and truncate it. Here we write all
of %rbp, but the low bits will be overwritten below. */
movq %rbp, (JB_RBP*8)(%rdi)
# endif
mov %RBP_LP, %RAX_LP
PTR_MANGLE (%RAX_LP)
mov %RAX_LP, (JB_RBP*8)(%rdi)
#else
movq %rbp, (JB_RBP*8)(%rdi)
#endif
movq %r12, (JB_R12*8)(%rdi)
movq %r13, (JB_R13*8)(%rdi)
movq %r14, (JB_R14*8)(%rdi)
movq %r15, (JB_R15*8)(%rdi)
lea 8(%rsp), %RDX_LP /* Save SP as it will be after we return. */
#ifdef PTR_MANGLE
PTR_MANGLE (%RDX_LP)
#endif
movq %rdx, (JB_RSP*8)(%rdi)
mov (%rsp), %RAX_LP /* Save PC we are returning to now. */
LIBC_PROBE (setjmp, 3, LP_SIZE@%RDI_LP, -4@%esi, LP_SIZE@%RAX_LP)
#ifdef PTR_MANGLE
PTR_MANGLE (%RAX_LP)
#endif
movq %rax, (JB_PC*8)(%rdi)
#ifdef SHADOW_STACK_POINTER_OFFSET
# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
/* Check if Shadow Stack is enabled. */
testl $X86_FEATURE_1_SHSTK, %fs:FEATURE_1_OFFSET
jz L(skip_ssp)
# else
xorl %eax, %eax
# endif
/* Get the current Shadow-Stack-Pointer and save it. */
rdsspq %rax
movq %rax, SHADOW_STACK_POINTER_OFFSET(%rdi)
# if IS_IN (libc) && defined SHARED && defined FEATURE_1_OFFSET
L(skip_ssp):
# endif
#endif
#if IS_IN (rtld)
/* In ld.so we never save the signal mask. */
xorl %eax, %eax
retq
#else
/* Make a tail call to __sigjmp_save; it takes the same args. */
jmp __sigjmp_save
#endif
END (__sigsetjmp)
hidden_def (__sigsetjmp)