platform_bionic/libc/arch-x86_64/bionic/setjmp.S
Josh Gao 686e5f6f69 Add a checksum to jmp_buf on x86_64.
Bug: http://b/27856501
Bug: http://b/27417786
Change-Id: I541f5a7ce4972ef56b3f69e73927ca7df362609a
2016-03-29 17:28:32 -07:00

209 lines
5.4 KiB
ArmAsm

/*
* Copyright (c) 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Frank van der Linden for Wasabi Systems, Inc.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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 <private/bionic_asm.h>
// The internal structure of a jmp_buf is totally private.
// Current layout (changes from release to release):
//
// word name description
// 0 rbx registers
// 1 rbp
// 2 r12
// 3 r13
// 4 r14
// 5 r15
// 6 rsp
// 7 pc
// 8 sigflag/cookie setjmp cookie in top 31 bits, signal mask flag in low bit
// 9 sigmask signal mask (includes rt signals as well)
// 10 checksum checksum of the core registers, to give better error messages.
#define _JB_RBX 0
#define _JB_RBP 1
#define _JB_R12 2
#define _JB_R13 3
#define _JB_R14 4
#define _JB_R15 5
#define _JB_RSP 6
#define _JB_PC 7
#define _JB_SIGFLAG 8
#define _JB_SIGMASK 9
#define _JB_CHECKSUM 10
#define MANGLE_REGISTERS 1
.macro m_mangle_registers reg
#if MANGLE_REGISTERS
xorq \reg,%rbx
xorq \reg,%rbp
xorq \reg,%r12
xorq \reg,%r13
xorq \reg,%r14
xorq \reg,%r15
xorq \reg,%rsp
xorq \reg,%r11
#endif
.endm
.macro m_unmangle_registers reg
m_mangle_registers \reg
.endm
.macro m_calculate_checksum dst, src
movq $0, \dst
.irp i,0,1,2,3,4,5,6,7
xorq (\i*8)(\src), \dst
.endr
.endm
ENTRY(setjmp)
movl $1,%esi
jmp PIC_PLT(sigsetjmp)
END(setjmp)
ENTRY(_setjmp)
movl $0,%esi
jmp PIC_PLT(sigsetjmp)
END(_setjmp)
// int sigsetjmp(sigjmp_buf env, int save_signal_mask);
ENTRY(sigsetjmp)
pushq %rdi
movq %rsi,%rdi
call PIC_PLT(__bionic_setjmp_cookie_get)
popq %rdi
// Record setjmp cookie and whether or not we're saving the signal mask.
movq %rax,(_JB_SIGFLAG * 8)(%rdi)
pushq %rax
// Do we need to save the signal mask?
testq $1,%rax
jz 2f
// Save current signal mask.
pushq %rdi // Push 'env'.
// The 'how' argument is ignored if new_mask is NULL.
xorq %rsi,%rsi // NULL.
leaq (_JB_SIGMASK * 8)(%rdi),%rdx // old_mask.
call PIC_PLT(sigprocmask)
popq %rdi // Pop 'env'.
2:
// Save the callee-save registers.
popq %rax
andq $-2,%rax
movq (%rsp),%r11
m_mangle_registers %rax
movq %rbx,(_JB_RBX * 8)(%rdi)
movq %rbp,(_JB_RBP * 8)(%rdi)
movq %r12,(_JB_R12 * 8)(%rdi)
movq %r13,(_JB_R13 * 8)(%rdi)
movq %r14,(_JB_R14 * 8)(%rdi)
movq %r15,(_JB_R15 * 8)(%rdi)
movq %rsp,(_JB_RSP * 8)(%rdi)
movq %r11,(_JB_PC * 8)(%rdi)
m_unmangle_registers %rax
m_calculate_checksum %rax, %rdi
movq %rax, (_JB_CHECKSUM * 8)(%rdi)
xorl %eax,%eax
ret
END(sigsetjmp)
// void siglongjmp(sigjmp_buf env, int value);
ENTRY(siglongjmp)
movq %rdi,%r12
pushq %rsi // Push 'value'.
m_calculate_checksum %rax, %rdi
xorq (_JB_CHECKSUM * 8)(%rdi), %rax
jnz 3f
// Do we need to restore the signal mask?
movq (_JB_SIGFLAG * 8)(%rdi), %rdi
pushq %rdi // Push cookie
testq $1, %rdi
jz 2f
// Restore the signal mask.
movq $2,%rdi // SIG_SETMASK.
leaq (_JB_SIGMASK * 8)(%r12),%rsi // new_mask.
xorq %rdx,%rdx // NULL.
call PIC_PLT(sigprocmask)
2:
// Fetch the setjmp cookie and clear the signal flag bit.
popq %rcx
andq $-2, %rcx
popq %rax // Pop 'value'.
// Restore the callee-save registers.
movq (_JB_RBX * 8)(%r12),%rbx
movq (_JB_RBP * 8)(%r12),%rbp
movq (_JB_R13 * 8)(%r12),%r13
movq (_JB_R14 * 8)(%r12),%r14
movq (_JB_R15 * 8)(%r12),%r15
movq (_JB_RSP * 8)(%r12),%rsp
movq (_JB_PC * 8)(%r12),%r11
movq (_JB_R12 * 8)(%r12),%r12
m_unmangle_registers %rcx
// Check the cookie.
pushq %rax
pushq %r11
movq %rcx, %rdi
call PIC_PLT(__bionic_setjmp_cookie_check)
popq %r11
popq %rax
// Return 1 if value is 0.
testl %eax,%eax
jnz 1f
incl %eax
1:
movq %r11,0(%rsp)
ret
3:
call PIC_PLT(__bionic_setjmp_checksum_mismatch)
END(siglongjmp)
ALIAS_SYMBOL(longjmp, siglongjmp)
ALIAS_SYMBOL(_longjmp, siglongjmp)