llvm-project/compiler-rt/lib/safestack/safestack_platform.h

125 lines
3.3 KiB
C++

//===-- safestack_platform.h ----------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements platform specific parts of SafeStack runtime.
//
//===----------------------------------------------------------------------===//
#ifndef SAFESTACK_PLATFORM_H
#define SAFESTACK_PLATFORM_H
#include "safestack_util.h"
#include "sanitizer_common/sanitizer_platform.h"
#include <dlfcn.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
#if !(SANITIZER_NETBSD || SANITIZER_FREEBSD || SANITIZER_LINUX)
#error "Support for your platform has not been implemented"
#endif
#if SANITIZER_NETBSD
#include <lwp.h>
extern "C" void *__mmap(void *, size_t, int, int, int, int, off_t);
#endif
#if SANITIZER_FREEBSD
#include <sys/thr.h>
#endif
namespace safestack {
#if SANITIZER_NETBSD
static void *GetRealLibcAddress(const char *symbol) {
void *real = dlsym(RTLD_NEXT, symbol);
if (!real)
real = dlsym(RTLD_DEFAULT, symbol);
if (!real) {
fprintf(stderr, "safestack GetRealLibcAddress failed for symbol=%s",
symbol);
abort();
}
return real;
}
#define _REAL(func, ...) real##_##func(__VA_ARGS__)
#define DEFINE__REAL(ret_type, func, ...) \
static ret_type (*real_##func)(__VA_ARGS__) = NULL; \
if (!real_##func) { \
real_##func = (ret_type(*)(__VA_ARGS__))GetRealLibcAddress(#func); \
} \
SFS_CHECK(real_##func);
#endif
using ThreadId = uint64_t;
inline ThreadId GetTid() {
#if SANITIZER_NETBSD
DEFINE__REAL(int, _lwp_self);
return _REAL(_lwp_self);
#elif SANITIZER_FREEBSD
long Tid;
thr_self(&Tid);
return Tid;
#else
return syscall(SYS_gettid);
#endif
}
inline int TgKill(pid_t pid, ThreadId tid, int sig) {
#if SANITIZER_NETBSD
DEFINE__REAL(int, _lwp_kill, int a, int b);
(void)pid;
return _REAL(_lwp_kill, tid, sig);
#elif SANITIZER_FREEBSD
return syscall(SYS_thr_kill2, pid, tid, sig);
#else
return syscall(SYS_tgkill, pid, tid, sig);
#endif
}
inline void *Mmap(void *addr, size_t length, int prot, int flags, int fd,
off_t offset) {
#if SANITIZER_NETBSD
return __mmap(addr, length, prot, flags, fd, 0, offset);
#elif SANITIZER_FREEBSD && (defined(__aarch64__) || defined(__x86_64__))
return (void *)__syscall(SYS_mmap, addr, length, prot, flags, fd, offset);
#else
return (void *)syscall(SYS_mmap, addr, length, prot, flags, fd, offset);
#endif
}
inline int Munmap(void *addr, size_t length) {
#if SANITIZER_NETBSD
DEFINE__REAL(int, munmap, void *a, size_t b);
return _REAL(munmap, addr, length);
#else
return syscall(SYS_munmap, addr, length);
#endif
}
inline int Mprotect(void *addr, size_t length, int prot) {
#if SANITIZER_NETBSD
DEFINE__REAL(int, mprotect, void *a, size_t b, int c);
return _REAL(mprotect, addr, length, prot);
#else
return syscall(SYS_mprotect, addr, length, prot);
#endif
}
} // namespace safestack
#endif // SAFESTACK_PLATFORM_H