1349cc55cSDimitry Andric//===-- hwasan_setjmp_x86_64.S --------------------------------------------===// 2349cc55cSDimitry Andric// 3349cc55cSDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4349cc55cSDimitry Andric// See https://llvm.org/LICENSE.txt for license information. 5349cc55cSDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6349cc55cSDimitry Andric// 7349cc55cSDimitry Andric//===----------------------------------------------------------------------===// 8349cc55cSDimitry Andric// 9349cc55cSDimitry Andric// setjmp interceptor for x86_64. 10349cc55cSDimitry Andric// 11349cc55cSDimitry Andric//===----------------------------------------------------------------------===// 12349cc55cSDimitry Andric 13349cc55cSDimitry Andric#include "sanitizer_common/sanitizer_asm.h" 14349cc55cSDimitry Andric 15349cc55cSDimitry Andric#if HWASAN_WITH_INTERCEPTORS && defined(__x86_64__) 16349cc55cSDimitry Andric#include "sanitizer_common/sanitizer_platform.h" 17349cc55cSDimitry Andric 18349cc55cSDimitry Andric// We want to save the context of the calling function. 19349cc55cSDimitry Andric// That requires 20349cc55cSDimitry Andric// 1) No modification of the return address by this function. 21349cc55cSDimitry Andric// 2) No modification of the stack pointer by this function. 22349cc55cSDimitry Andric// 3) (no modification of any other saved register, but that's not really going 23349cc55cSDimitry Andric// to occur, and hence isn't as much of a worry). 24349cc55cSDimitry Andric// 25349cc55cSDimitry Andric// There's essentially no way to ensure that the compiler will not modify the 26349cc55cSDimitry Andric// stack pointer when compiling a C function. 27349cc55cSDimitry Andric// Hence we have to write this function in assembly. 28349cc55cSDimitry Andric// 29349cc55cSDimitry Andric// TODO: Handle Intel CET. 30349cc55cSDimitry Andric 31349cc55cSDimitry Andric.section .text 32349cc55cSDimitry Andric.file "hwasan_setjmp_x86_64.S" 33349cc55cSDimitry Andric 34*06c3fb27SDimitry Andric.global ASM_WRAPPER_NAME(setjmp) 35*06c3fb27SDimitry AndricASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(setjmp)) 36*06c3fb27SDimitry AndricASM_WRAPPER_NAME(setjmp): 37349cc55cSDimitry Andric CFI_STARTPROC 38349cc55cSDimitry Andric _CET_ENDBR 39349cc55cSDimitry Andric xorl %esi, %esi 40*06c3fb27SDimitry Andric jmp .Linterceptor_sigsetjmp 41349cc55cSDimitry Andric CFI_ENDPROC 42*06c3fb27SDimitry AndricASM_SIZE(ASM_WRAPPER_NAME(setjmp)) 43349cc55cSDimitry Andric 44*06c3fb27SDimitry Andric.global ASM_WRAPPER_NAME(sigsetjmp) 45*06c3fb27SDimitry AndricASM_TYPE_FUNCTION(ASM_WRAPPER_NAME(sigsetjmp)) 46*06c3fb27SDimitry AndricASM_WRAPPER_NAME(sigsetjmp): 47*06c3fb27SDimitry Andric.Linterceptor_sigsetjmp: 48349cc55cSDimitry Andric CFI_STARTPROC 49349cc55cSDimitry Andric _CET_ENDBR 50349cc55cSDimitry Andric 51349cc55cSDimitry Andric // Save callee save registers. 52349cc55cSDimitry Andric mov %rbx, (0*8)(%rdi) 53349cc55cSDimitry Andric mov %rbp, (1*8)(%rdi) 54349cc55cSDimitry Andric mov %r12, (2*8)(%rdi) 55349cc55cSDimitry Andric mov %r13, (3*8)(%rdi) 56349cc55cSDimitry Andric mov %r14, (4*8)(%rdi) 57349cc55cSDimitry Andric mov %r15, (5*8)(%rdi) 58349cc55cSDimitry Andric 59349cc55cSDimitry Andric // Save SP as it was in caller's frame. 60349cc55cSDimitry Andric lea 8(%rsp), %rdx 61349cc55cSDimitry Andric mov %rdx, (6*8)(%rdi) 62349cc55cSDimitry Andric 63349cc55cSDimitry Andric // Save return address. 64349cc55cSDimitry Andric mov (%rsp), %rax 65349cc55cSDimitry Andric mov %rax, (7*8)(%rdi) 66349cc55cSDimitry Andric 67349cc55cSDimitry Andric jmp __sigjmp_save 68349cc55cSDimitry Andric 69349cc55cSDimitry Andric CFI_ENDPROC 70*06c3fb27SDimitry AndricASM_SIZE(ASM_WRAPPER_NAME(sigsetjmp)) 71349cc55cSDimitry Andric 72*06c3fb27SDimitry AndricASM_INTERCEPTOR_TRAMPOLINE(sigsetjmp) 73*06c3fb27SDimitry AndricASM_TRAMPOLINE_ALIAS(__sigsetjmp, sigsetjmp) 74*06c3fb27SDimitry AndricASM_INTERCEPTOR_TRAMPOLINE(setjmp) 75*06c3fb27SDimitry AndricASM_TRAMPOLINE_ALIAS(_setjmp, setjmp) 76349cc55cSDimitry Andric#endif 77349cc55cSDimitry Andric 78349cc55cSDimitry Andric// We do not need executable stack. 79349cc55cSDimitry AndricNO_EXEC_STACK_DIRECTIVE 80