llvm-project/compiler-rt/lib/msan/msan_linux.cc

109 lines
3.2 KiB
C++

//===-- msan_linux.cc -----------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of MemorySanitizer.
//
// Linux-specific code.
//===----------------------------------------------------------------------===//
#ifdef __linux__
#include "msan.h"
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <unwind.h>
#include <execinfo.h>
#include <sys/time.h>
#include <sys/resource.h>
#include "sanitizer_common/sanitizer_common.h"
#include "sanitizer_common/sanitizer_procmaps.h"
namespace __msan {
static const uptr kMemBeg = 0x600000000000;
static const uptr kMemEnd = 0x7fffffffffff;
static const uptr kShadowBeg = MEM_TO_SHADOW(kMemBeg);
static const uptr kShadowEnd = MEM_TO_SHADOW(kMemEnd);
static const uptr kBad1Beg = 0x100000000; // 4G
static const uptr kBad1End = kShadowBeg - 1;
static const uptr kBad2Beg = kShadowEnd + 1;
static const uptr kBad2End = kMemBeg - 1;
static const uptr kOriginsBeg = kBad2Beg;
static const uptr kOriginsEnd = kBad2End;
bool InitShadow(bool prot1, bool prot2, bool map_shadow, bool init_origins) {
if (flags()->verbosity) {
Printf("__msan_init %p\n", &__msan_init);
Printf("Memory : %p %p\n", kMemBeg, kMemEnd);
Printf("Bad2 : %p %p\n", kBad2Beg, kBad2End);
Printf("Origins : %p %p\n", kOriginsBeg, kOriginsEnd);
Printf("Shadow : %p %p\n", kShadowBeg, kShadowEnd);
Printf("Bad1 : %p %p\n", kBad1Beg, kBad1End);
}
if (!MemoryRangeIsAvailable(kShadowBeg,
init_origins ? kOriginsEnd : kShadowEnd)) {
Printf("FATAL: Shadow memory range is not available.\n");
return false;
}
if (prot1 && !Mprotect(kBad1Beg, kBad1End - kBad1Beg))
return false;
if (prot2 && !Mprotect(kBad2Beg, kBad2End - kBad2Beg))
return false;
if (map_shadow) {
void *shadow = MmapFixedNoReserve(kShadowBeg, kShadowEnd - kShadowBeg);
if (shadow != (void*)kShadowBeg) return false;
}
if (init_origins) {
void *origins = MmapFixedNoReserve(kOriginsBeg, kOriginsEnd - kOriginsBeg);
if (origins != (void*)kOriginsBeg) return false;
}
return true;
}
static void MsanTrap(int, siginfo_t *siginfo, void *context) {
ucontext_t *ucontext = (ucontext_t*)context;
uptr pc = ucontext->uc_mcontext.gregs[REG_RIP];
uptr bp = ucontext->uc_mcontext.gregs[REG_RBP];
PrintWarning(pc + 1 /*1 will be subtracted in StackTrace::Print */, bp);
ucontext->uc_mcontext.gregs[REG_RIP] += 2;
}
void InstallTrapHandler() {
struct sigaction sigact;
internal_memset(&sigact, 0, sizeof(sigact));
sigact.sa_sigaction = MsanTrap;
sigact.sa_flags = SA_SIGINFO;
CHECK_EQ(0, sigaction(SIGILL, &sigact, 0));
}
void MsanDie() {
_exit(flags()->exit_code);
}
static void MsanAtExit(void) {
if (msan_report_count > 0) {
ReportAtExitStatistics();
if (flags()->exit_code)
_exit(flags()->exit_code);
}
}
void InstallAtExitHandler() {
atexit(MsanAtExit);
}
}
#endif // __linux__