blob: 2b53d7d730d7e45bc90746ad6ac871ad947ce080 [file] [log] [blame]
//===-- sanitizer_mac.cpp -------------------------------------------------===//
//
// 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 is shared between various sanitizers' runtime libraries and
// implements OSX-specific functions.
//===----------------------------------------------------------------------===//
#include "sanitizer_platform.h"
#if SANITIZER_MAC
#include "sanitizer_mac.h"
#include "interception/interception.h"
// Use 64-bit inodes in file operations. ASan does not support OS X 10.5, so
// the clients will most certainly use 64-bit ones as well.
#ifndef _DARWIN_USE_64_BIT_INODE
#define _DARWIN_USE_64_BIT_INODE 1
#endif
#include <stdio.h>
#include "sanitizer_common.h"
#include "sanitizer_file.h"
#include "sanitizer_flags.h"
#include "sanitizer_internal_defs.h"
#include "sanitizer_libc.h"
#include "sanitizer_platform_limits_posix.h"
#include "sanitizer_procmaps.h"
#include "sanitizer_ptrauth.h"
#if !SANITIZER_IOS
#include <crt_externs.h> // for _NSGetEnviron
#else
extern char **environ;
#endif
#if defined(__has_include) && __has_include(<os/trace.h>)
#define SANITIZER_OS_TRACE 1
#include <os/trace.h>
#else
#define SANITIZER_OS_TRACE 0
#endif
#if !SANITIZER_IOS
#include <crt_externs.h> // for _NSGetArgv and _NSGetEnviron
#else
extern "C" {
extern char ***_NSGetArgv(void);
}
#endif
#include <asl.h>
#include <dlfcn.h> // for dladdr()
#include <errno.h>
#include <fcntl.h>
#include <libkern/OSAtomic.h>
#include <mach-o/dyld.h>
#include <mach/mach.h>
#include <mach/mach_time.h>
#include <mach/vm_statistics.h>
#include <malloc/malloc.h>
#include <pthread.h>
#include <sched.h>
#include <signal.h>
#include <spawn.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <util.h>
// From <crt_externs.h>, but we don't have that file on iOS.
extern "C" {
extern char ***_NSGetArgv(void);
extern char ***_NSGetEnviron(void);
}
// From <mach/mach_vm.h>, but we don't have that file on iOS.
extern "C" {
extern kern_return_t mach_vm_region_recurse(
vm_map_t target_task,
mach_vm_address_t *address,
mach_vm_size_t *size,
natural_t *nesting_depth,
vm_region_recurse_info_t info,
mach_msg_type_number_t *infoCnt);
}
namespace __sanitizer {
#include "sanitizer_syscall_generic.inc"
// Direct syscalls, don't call libmalloc hooks (but not available on 10.6).
extern "C" void *__mmap(void *addr, size_t len, int prot, int flags, int fildes,
off_t off) SANITIZER_WEAK_ATTRIBUTE;
extern "C" int __munmap(void *, size_t) SANITIZER_WEAK_ATTRIBUTE;
// ---------------------- sanitizer_libc.h
// From <mach/vm_statistics.h>, but not on older OSs.
#ifndef VM_MEMORY_SANITIZER
#define VM_MEMORY_SANITIZER 99
#endif
// XNU on Darwin provides a mmap flag that optimizes allocation/deallocation of
// giant memory regions (i.e. shadow memory regions).
#define kXnuFastMmapFd 0x4
static size_t kXnuFastMmapThreshold = 2 << 30; // 2 GB
static bool use_xnu_fast_mmap = false;
uptr internal_mmap(void *addr, size_t length, int prot, int flags,
int fd, u64 offset) {
if (fd == -1) {
fd = VM_MAKE_TAG(VM_MEMORY_SANITIZER);
if (length >= kXnuFastMmapThreshold) {
if (use_xnu_fast_mmap) fd |= kXnuFastMmapFd;
}
}
if (&__mmap) return (uptr)__mmap(addr, length, prot, flags, fd, offset);
return (uptr)mmap(addr, length, prot, flags, fd, offset);
}
uptr internal_munmap(void *addr, uptr length) {
if (&__munmap) return __munmap(addr, length);
return munmap(addr, length);
}
int internal_mprotect(void *addr, uptr length, int prot) {
return mprotect(addr, length, prot);
}
int internal_madvise(uptr addr, uptr length, int advice) {
return madvise((void *)addr, length, advice);
}
uptr internal_close(fd_t fd) {
return close(fd);
}
uptr internal_open(const char *filename, int flags) {
return open(filename, flags);
}
uptr internal_open(const char *filename, int flags, u32 mode) {
return open(filename, flags, mode);
}
uptr internal_read(fd_t fd, void *buf, uptr count) {
return read(fd, buf, count);
}
uptr internal_write(fd_t fd, const void *buf, uptr count) {
return write(fd, buf, count);
}
uptr internal_stat(const char *path, void *buf) {
return stat(path, (struct stat *)buf);
}
uptr internal_lstat(const char *path, void *buf) {
return lstat(path, (struct stat *)buf);
}
uptr internal_fstat(fd_t fd, void *buf) {
return fstat(fd, (struct stat *)buf);
}
uptr internal_filesize(fd_t fd) {
struct stat st;
if (internal_fstat(fd, &st))
return -1;
return (uptr)st.st_size;
}
uptr internal_dup(int oldfd) {
return dup(oldfd);
}
uptr internal_dup2(int oldfd, int newfd) {
return dup2(oldfd, newfd);
}
uptr internal_readlink(const char *path, char *buf, uptr bufsize) {
return readlink(path, buf, bufsize);
}
uptr internal_unlink(const char *path) {
return unlink(path);
}
uptr internal_sched_yield() {
return sched_yield();
}
void internal__exit(int exitcode) {
_exit(exitcode);
}
unsigned int internal_sleep(unsigned int seconds) {
return sleep(seconds);
}
uptr internal_getpid() {
return getpid();
}
int internal_dlinfo(void *handle, int request, void *p) {
UNIMPLEMENTED();
}
int internal_sigaction(int signum, const void *act, void *oldact) {
return sigaction(signum,
(const struct sigaction *)act, (struct sigaction *)oldact);
}
void internal_sigfillset(__sanitizer_sigset_t *set) { sigfillset(set); }
uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
__sanitizer_sigset_t *oldset) {
// Don't use sigprocmask here, because it affects all threads.
return pthread_sigmask(how, set, oldset);
}
// Doesn't call pthread_atfork() handlers (but not available on 10.6).
extern "C" pid_t __fork(void) SANITIZER_WEAK_ATTRIBUTE;
int internal_fork() {
if (&__fork)
return __fork();
return fork();
}
int internal_sysctl(const int *name, unsigned int namelen, void *oldp,
uptr *oldlenp, const void *newp, uptr newlen) {
return sysctl(const_cast<int *>(name), namelen, oldp, (size_t *)oldlenp,
const_cast<void *>(newp), (size_t)newlen);
}
int internal_sysctlbyname(const char *sname, void *oldp, uptr *oldlenp,
const void *newp, uptr newlen) {
return sysctlbyname(sname, oldp, (size_t *)oldlenp, const_cast<void *>(newp),
(size_t)newlen);
}
static fd_t internal_spawn_impl(const char *argv[], const char *envp[],
pid_t *pid) {
fd_t master_fd = kInvalidFd;
fd_t slave_fd = kInvalidFd;
auto fd_closer = at_scope_exit([&] {
internal_close(master_fd);
internal_close(slave_fd);
});
// We need a new pseudoterminal to avoid buffering problems. The 'atos' tool
// in particular detects when it's talking to a pipe and forgets to flush the
// output stream after sending a response.
master_fd = posix_openpt(O_RDWR);
if (master_fd == kInvalidFd) return kInvalidFd;
int res = grantpt(master_fd) || unlockpt(master_fd);
if (res != 0) return kInvalidFd;
// Use TIOCPTYGNAME instead of ptsname() to avoid threading problems.
char slave_pty_name[128];
res = ioctl(master_fd, TIOCPTYGNAME, slave_pty_name);
if (res == -1) return kInvalidFd;
slave_fd = internal_open(slave_pty_name, O_RDWR);
if (slave_fd == kInvalidFd) return kInvalidFd;
// File descriptor actions
posix_spawn_file_actions_t acts;
res = posix_spawn_file_actions_init(&acts);
if (res != 0) return kInvalidFd;
auto acts_cleanup = at_scope_exit([&] {
posix_spawn_file_actions_destroy(&acts);
});
res = posix_spawn_file_actions_adddup2(&acts, slave_fd, STDIN_FILENO) ||
posix_spawn_file_actions_adddup2(&acts, slave_fd, STDOUT_FILENO) ||
posix_spawn_file_actions_addclose(&acts, slave_fd);
if (res != 0) return kInvalidFd;
// Spawn attributes
posix_spawnattr_t attrs;
res = posix_spawnattr_init(&attrs);
if (res != 0) return kInvalidFd;
auto attrs_cleanup = at_scope_exit([&] {
posix_spawnattr_destroy(&attrs);
});
// In the spawned process, close all file descriptors that are not explicitly
// described by the file actions object. This is Darwin-specific extension.
res = posix_spawnattr_setflags(&attrs, POSIX_SPAWN_CLOEXEC_DEFAULT);
if (res != 0) return kInvalidFd;
// posix_spawn
char **argv_casted = const_cast<char **>(argv);
char **envp_casted = const_cast<char **>(envp);
res = posix_spawn(pid, argv[0], &acts, &attrs, argv_casted, envp_casted);
if (res != 0) return kInvalidFd;
// Disable echo in the new terminal, disable CR.
struct termios termflags;
tcgetattr(master_fd, &termflags);
termflags.c_oflag &= ~ONLCR;
termflags.c_lflag &= ~ECHO;
tcsetattr(master_fd, TCSANOW, &termflags);
// On success, do not close master_fd on scope exit.
fd_t fd = master_fd;
master_fd = kInvalidFd;
return fd;
}
fd_t internal_spawn(const char *argv[], const char *envp[], pid_t *pid) {
// The client program may close its stdin and/or stdout and/or stderr thus
// allowing open/posix_openpt to reuse file descriptors 0, 1 or 2. In this
// case the communication is broken if either the parent or the child tries to
// close or duplicate these descriptors. We temporarily reserve these
// descriptors here to prevent this.
fd_t low_fds[3];
size_t count = 0;
for (; count < 3; count++) {
low_fds[count] = posix_openpt(O_RDWR);
if (low_fds[count] >= STDERR_FILENO)
break;
}
fd_t fd = internal_spawn_impl(argv, envp, pid);
for (; count > 0; count--) {
internal_close(low_fds[count]);
}
return fd;
}
uptr internal_rename(const char *oldpath, const char *newpath) {
return rename(oldpath, newpath);
}
uptr internal_ftruncate(fd_t fd, uptr size) {
return ftruncate(fd, size);
}
uptr internal_execve(const char *filename, char *const argv[],
char *const envp[]) {
return execve(filename, argv, envp);
}
uptr internal_waitpid(int pid, int *status, int options) {
return waitpid(pid, status, options);
}
// ----------------- sanitizer_common.h
bool FileExists(const char *filename) {
if (ShouldMockFailureToOpen(filename))
return false;
struct stat st;
if (stat(filename, &st))
return false;
// Sanity check: filename is a regular file.
return S_ISREG(st.st_mode);
}
tid_t GetTid() {
tid_t tid;
pthread_threadid_np(nullptr, &tid);
return tid;
}
void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
uptr *stack_bottom) {
CHECK(stack_top);
CHECK(stack_bottom);
uptr stacksize = pthread_get_stacksize_np(pthread_self());
// pthread_get_stacksize_np() returns an incorrect stack size for the main
// thread on Mavericks. See
// https://github.com/google/sanitizers/issues/261
if ((GetMacosAlignedVersion() >= MacosVersion(10, 9)) && at_initialization &&
stacksize == (1 << 19)) {
struct rlimit rl;
CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
// Most often rl.rlim_cur will be the desired 8M.
if (rl.rlim_cur < kMaxThreadStackSize) {
stacksize = rl.rlim_cur;
} else {
stacksize = kMaxThreadStackSize;
}
}
void *stackaddr = pthread_get_stackaddr_np(pthread_self());
*stack_top = (uptr)stackaddr;
*stack_bottom = *stack_top - stacksize;
}
char **GetEnviron() {
#if !SANITIZER_IOS
char ***env_ptr = _NSGetEnviron();
if (!env_ptr) {
Report("_NSGetEnviron() returned NULL. Please make sure __asan_init() is "
"called after libSystem_initializer().\n");
CHECK(env_ptr);
}
char **environ = *env_ptr;
#endif
CHECK(environ);
return environ;
}
const char *GetEnv(const char *name) {
char **env = GetEnviron();
uptr name_len = internal_strlen(name);
while (*env != 0) {
uptr len = internal_strlen(*env);
if (len > name_len) {
const char *p = *env;
if (!internal_memcmp(p, name, name_len) &&
p[name_len] == '=') { // Match.
return *env + name_len + 1; // String starting after =.
}
}
env++;
}
return 0;
}
uptr ReadBinaryName(/*out*/char *buf, uptr buf_len) {
CHECK_LE(kMaxPathLength, buf_len);
// On OS X the executable path is saved to the stack by dyld. Reading it
// from there is much faster than calling dladdr, especially for large
// binaries with symbols.
InternalScopedString exe_path(kMaxPathLength);
uint32_t size = exe_path.size();
if (_NSGetExecutablePath(exe_path.data(), &size) == 0 &&
realpath(exe_path.data(), buf) != 0) {
return internal_strlen(buf);
}
return 0;
}
uptr ReadLongProcessName(/*out*/char *buf, uptr buf_len) {
return ReadBinaryName(buf, buf_len);
}
void ReExec() {
UNIMPLEMENTED();
}
void CheckASLR() {
// Do nothing
}
void CheckMPROTECT() {
// Do nothing
}
uptr GetPageSize() {
return sysconf(_SC_PAGESIZE);
}
extern "C" unsigned malloc_num_zones;
extern "C" malloc_zone_t **malloc_zones;
malloc_zone_t sanitizer_zone;
// We need to make sure that sanitizer_zone is registered as malloc_zones[0]. If
// libmalloc tries to set up a different zone as malloc_zones[0], it will call
// mprotect(malloc_zones, ..., PROT_READ). This interceptor will catch that and
// make sure we are still the first (default) zone.
void MprotectMallocZones(void *addr, int prot) {
if (addr == malloc_zones && prot == PROT_READ) {
if (malloc_num_zones > 1 && malloc_zones[0] != &sanitizer_zone) {
for (unsigned i = 1; i < malloc_num_zones; i++) {
if (malloc_zones[i] == &sanitizer_zone) {
// Swap malloc_zones[0] and malloc_zones[i].
malloc_zones[i] = malloc_zones[0];
malloc_zones[0] = &sanitizer_zone;
break;
}
}
}
}
}
BlockingMutex::BlockingMutex() {
internal_memset(this, 0, sizeof(*this));
}
void BlockingMutex::Lock() {
CHECK(sizeof(OSSpinLock) <= sizeof(opaque_storage_));
CHECK_EQ(OS_SPINLOCK_INIT, 0);
CHECK_EQ(owner_, 0);
OSSpinLockLock((OSSpinLock*)&opaque_storage_);
}
void BlockingMutex::Unlock() {
OSSpinLockUnlock((OSSpinLock*)&opaque_storage_);
}
void BlockingMutex::CheckLocked() {
CHECK_NE(*(OSSpinLock*)&opaque_storage_, 0);
}
u64 NanoTime() {
timeval tv;
internal_memset(&tv, 0, sizeof(tv));
gettimeofday(&tv, 0);
return (u64)tv.tv_sec * 1000*1000*1000 + tv.tv_usec * 1000;
}
// This needs to be called during initialization to avoid being racy.
u64 MonotonicNanoTime() {
static mach_timebase_info_data_t timebase_info;
if (timebase_info.denom == 0) mach_timebase_info(&timebase_info);
return (mach_absolute_time() * timebase_info.numer) / timebase_info.denom;
}
uptr GetTlsSize() {
return 0;
}
void InitTlsSize() {
}
uptr TlsBaseAddr() {
uptr segbase = 0;
#if defined(__x86_64__)
asm("movq %%gs:0,%0" : "=r"(segbase));
#elif defined(__i386__)
asm("movl %%gs:0,%0" : "=r"(segbase));
#endif
return segbase;
}
// The size of the tls on darwin does not appear to be well documented,
// however the vm memory map suggests that it is 1024 uptrs in size,
// with a size of 0x2000 bytes on x86_64 and 0x1000 bytes on i386.
uptr TlsSize() {
#if defined(__x86_64__) || defined(__i386__)
return 1024 * sizeof(uptr);
#else
return 0;
#endif
}
void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
uptr *tls_addr, uptr *tls_size) {
#if !SANITIZER_GO
uptr stack_top, stack_bottom;
GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
*stk_addr = stack_bottom;
*stk_size = stack_top - stack_bottom;
*tls_addr = TlsBaseAddr();
*tls_size = TlsSize();
#else
*stk_addr = 0;
*stk_size = 0;
*tls_addr = 0;
*tls_size = 0;
#endif
}
void ListOfModules::init() {
clearOrInit();
MemoryMappingLayout memory_mapping(false);
memory_mapping.DumpListOfModules(&modules_);
}
void ListOfModules::fallbackInit() { clear(); }
static HandleSignalMode GetHandleSignalModeImpl(int signum) {
switch (signum) {
case SIGABRT:
return common_flags()->handle_abort;
case SIGILL:
return common_flags()->handle_sigill;
case SIGTRAP:
return common_flags()->handle_sigtrap;
case SIGFPE:
return common_flags()->handle_sigfpe;
case SIGSEGV:
return common_flags()->handle_segv;
case SIGBUS:
return common_flags()->handle_sigbus;
}
return kHandleSignalNo;
}
HandleSignalMode GetHandleSignalMode(int signum) {
// Handling fatal signals on watchOS and tvOS devices is disallowed.
if ((SANITIZER_WATCHOS || SANITIZER_TVOS) && !(SANITIZER_IOSSIM))
return kHandleSignalNo;
HandleSignalMode result = GetHandleSignalModeImpl(signum);
if (result == kHandleSignalYes && !common_flags()->allow_user_segv_handler)
return kHandleSignalExclusive;
return result;
}
// Offset example:
// XNU 17 -- macOS 10.13 -- iOS 11 -- tvOS 11 -- watchOS 4
constexpr u16 GetOSMajorKernelOffset() {
if (TARGET_OS_OSX) return 4;
if (TARGET_OS_IOS || TARGET_OS_TV) return 6;
if (TARGET_OS_WATCH) return 13;
}
using VersStr = char[64];
static uptr ApproximateOSVersionViaKernelVersion(VersStr vers) {
u16 kernel_major = GetDarwinKernelVersion().major;
u16 offset = GetOSMajorKernelOffset();
CHECK_GE(kernel_major, offset);
u16 os_major = kernel_major - offset;
const char *format = "%d.0";
if (TARGET_OS_OSX) {
if (os_major >= 16) { // macOS 11+
os_major -= 5;
} else { // macOS 10.15 and below
format = "10.%d";
}
}
return internal_snprintf(vers, sizeof(VersStr), format, os_major);
}
static void GetOSVersion(VersStr vers) {
uptr len = sizeof(VersStr);
if (SANITIZER_IOSSIM) {
const char *vers_env = GetEnv("SIMULATOR_RUNTIME_VERSION");
if (!vers_env) {
Report("ERROR: Running in simulator but SIMULATOR_RUNTIME_VERSION env "
"var is not set.\n");
Die();
}
len = internal_strlcpy(vers, vers_env, len);
} else {
int res =
internal_sysctlbyname("kern.osproductversion", vers, &len, nullptr, 0);
// XNU 17 (macOS 10.13) and below do not provide the sysctl
// `kern.osproductversion` entry (res != 0).
bool no_os_version = res != 0;
// For launchd, sanitizer initialization runs before sysctl is setup
// (res == 0 && len != strlen(vers), vers is not a valid version). However,
// the kernel version `kern.osrelease` is available.
bool launchd = (res == 0 && internal_strlen(vers) < 3);
if (launchd) CHECK_EQ(internal_getpid(), 1);
if (no_os_version || launchd) {
len = ApproximateOSVersionViaKernelVersion(vers);
}
}
CHECK_LT(len, sizeof(VersStr));
}
void ParseVersion(const char *vers, u16 *major, u16 *minor) {
// Format: <major>.<minor>[.<patch>]\0
CHECK_GE(internal_strlen(vers), 3);
const char *p = vers;
*major = internal_simple_strtoll(p, &p, /*base=*/10);
CHECK_EQ(*p, '.');
p += 1;
*minor = internal_simple_strtoll(p, &p, /*base=*/10);
}
// Aligned versions example:
// macOS 10.15 -- iOS 13 -- tvOS 13 -- watchOS 6
static void MapToMacos(u16 *major, u16 *minor) {
if (TARGET_OS_OSX)
return;
if (TARGET_OS_IOS || TARGET_OS_TV)
*major += 2;
else if (TARGET_OS_WATCH)
*major += 9;
else
UNREACHABLE("unsupported platform");
if (*major >= 16) { // macOS 11+
*major -= 5;
} else { // macOS 10.15 and below
*minor = *major;
*major = 10;
}
}
static MacosVersion GetMacosAlignedVersionInternal() {
VersStr vers = {};
GetOSVersion(vers);
u16 major, minor;
ParseVersion(vers, &major, &minor);
MapToMacos(&major, &minor);
return MacosVersion(major, minor);
}
static_assert(sizeof(MacosVersion) == sizeof(atomic_uint32_t::Type),
"MacosVersion cache size");
static atomic_uint32_t cached_macos_version;
MacosVersion GetMacosAlignedVersion() {
atomic_uint32_t::Type result =
atomic_load(&cached_macos_version, memory_order_acquire);
if (!result) {
MacosVersion version = GetMacosAlignedVersionInternal();
result = *reinterpret_cast<atomic_uint32_t::Type *>(&version);
atomic_store(&cached_macos_version, result, memory_order_release);
}
return *reinterpret_cast<MacosVersion *>(&result);
}
DarwinKernelVersion GetDarwinKernelVersion() {
VersStr vers = {};
uptr len = sizeof(VersStr);
int res = internal_sysctlbyname("kern.osrelease", vers, &len, nullptr, 0);
CHECK_EQ(res, 0);
CHECK_LT(len, sizeof(VersStr));
u16 major, minor;
ParseVersion(vers, &major, &minor);
return DarwinKernelVersion(major, minor);
}
uptr GetRSS() {
struct task_basic_info info;
unsigned count = TASK_BASIC_INFO_COUNT;
kern_return_t result =
task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)&info, &count);
if (UNLIKELY(result != KERN_SUCCESS)) {
Report("Cannot get task info. Error: %d\n", result);
Die();
}
return info.resident_size;
}
void *internal_start_thread(void *(*func)(void *arg), void *arg) {
// Start the thread with signals blocked, otherwise it can steal user signals.
__sanitizer_sigset_t set, old;
internal_sigfillset(&set);
internal_sigprocmask(SIG_SETMASK, &set, &old);
pthread_t th;
pthread_create(&th, 0, func, arg);
internal_sigprocmask(SIG_SETMASK, &old, 0);
return th;
}
void internal_join_thread(void *th) { pthread_join((pthread_t)th, 0); }
#if !SANITIZER_GO
static BlockingMutex syslog_lock(LINKER_INITIALIZED);
#endif
void WriteOneLineToSyslog(const char *s) {
#if !SANITIZER_GO
syslog_lock.CheckLocked();
asl_log(nullptr, nullptr, ASL_LEVEL_ERR, "%s", s);
#endif
}
void LogMessageOnPrintf(const char *str) {
// Log all printf output to CrashLog.
if (common_flags()->abort_on_error)
CRAppendCrashLogMessage(str);
}
void LogFullErrorReport(const char *buffer) {
#if !SANITIZER_GO
// Log with os_trace. This will make it into the crash log.
#if SANITIZER_OS_TRACE
if (GetMacosAlignedVersion() >= MacosVersion(10, 10)) {
// os_trace requires the message (format parameter) to be a string literal.
if (internal_strncmp(SanitizerToolName, "AddressSanitizer",
sizeof("AddressSanitizer") - 1) == 0)
os_trace("Address Sanitizer reported a failure.");
else if (internal_strncmp(SanitizerToolName, "UndefinedBehaviorSanitizer",
sizeof("UndefinedBehaviorSanitizer") - 1) == 0)
os_trace("Undefined Behavior Sanitizer reported a failure.");
else if (internal_strncmp(SanitizerToolName, "ThreadSanitizer",
sizeof("ThreadSanitizer") - 1) == 0)
os_trace("Thread Sanitizer reported a failure.");
else
os_trace("Sanitizer tool reported a failure.");
if (common_flags()->log_to_syslog)
os_trace("Consult syslog for more information.");
}
#endif
// Log to syslog.
// The logging on OS X may call pthread_create so we need the threading
// environment to be fully initialized. Also, this should never be called when
// holding the thread registry lock since that may result in a deadlock. If
// the reporting thread holds the thread registry mutex, and asl_log waits
// for GCD to dispatch a new thread, the process will deadlock, because the
// pthread_create wrapper needs to acquire the lock as well.
BlockingMutexLock l(&syslog_lock);
if (common_flags()->log_to_syslog)
WriteToSyslog(buffer);
// The report is added to CrashLog as part of logging all of Printf output.
#endif
}
SignalContext::WriteFlag SignalContext::GetWriteFlag() const {
#if defined(__x86_64__) || defined(__i386__)
ucontext_t *ucontext = static_cast<ucontext_t*>(context);
return ucontext->uc_mcontext->__es.__err & 2 /*T_PF_WRITE*/ ? WRITE : READ;
#else
return UNKNOWN;
#endif
}
bool SignalContext::IsTrueFaultingAddress() const {
auto si = static_cast<const siginfo_t *>(siginfo);
// "Real" SIGSEGV codes (e.g., SEGV_MAPERR, SEGV_MAPERR) are non-zero.
return si->si_signo == SIGSEGV && si->si_code != 0;
}
#if defined(__aarch64__) && defined(arm_thread_state64_get_sp)
#define AARCH64_GET_REG(r) \
(uptr)ptrauth_strip( \
(void *)arm_thread_state64_get_##r(ucontext->uc_mcontext->__ss), 0)
#else
#define AARCH64_GET_REG(r) ucontext->uc_mcontext->__ss.__##r
#endif
static void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
ucontext_t *ucontext = (ucontext_t*)context;
# if defined(__aarch64__)
*pc = AARCH64_GET_REG(pc);
# if defined(__IPHONE_8_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_8_0
*bp = AARCH64_GET_REG(fp);
# else
*bp = AARCH64_GET_REG(lr);
# endif
*sp = AARCH64_GET_REG(sp);
# elif defined(__x86_64__)
*pc = ucontext->uc_mcontext->__ss.__rip;
*bp = ucontext->uc_mcontext->__ss.__rbp;
*sp = ucontext->uc_mcontext->__ss.__rsp;
# elif defined(__arm__)
*pc = ucontext->uc_mcontext->__ss.__pc;
*bp = ucontext->uc_mcontext->__ss.__r[7];
*sp = ucontext->uc_mcontext->__ss.__sp;
# elif defined(__i386__)
*pc = ucontext->uc_mcontext->__ss.__eip;
*bp = ucontext->uc_mcontext->__ss.__ebp;
*sp = ucontext->uc_mcontext->__ss.__esp;
# else
# error "Unknown architecture"
# endif
}
void SignalContext::InitPcSpBp() {
addr = (uptr)ptrauth_strip((void *)addr, 0);
GetPcSpBp(context, &pc, &sp, &bp);
}
// ASan/TSan use mmap in a way that creates “deallocation gaps” which triggers
// EXC_GUARD exceptions on macOS 10.15+ (XNU 19.0+).
static void DisableMmapExcGuardExceptions() {
using task_exc_guard_behavior_t = uint32_t;
using task_set_exc_guard_behavior_t =
kern_return_t(task_t task, task_exc_guard_behavior_t behavior);
auto *set_behavior = (task_set_exc_guard_behavior_t *)dlsym(
RTLD_DEFAULT, "task_set_exc_guard_behavior");
if (set_behavior == nullptr) return;
const task_exc_guard_behavior_t task_exc_guard_none = 0;
set_behavior(mach_task_self(), task_exc_guard_none);
}
void InitializePlatformEarly() {
// Only use xnu_fast_mmap when on x86_64 and the kernel supports it.
use_xnu_fast_mmap =
#if defined(__x86_64__)
GetDarwinKernelVersion() >= DarwinKernelVersion(17, 5);
#else
false;
#endif
if (GetDarwinKernelVersion() >= DarwinKernelVersion(19, 0))
DisableMmapExcGuardExceptions();
}
#if !SANITIZER_GO
static const char kDyldInsertLibraries[] = "DYLD_INSERT_LIBRARIES";
LowLevelAllocator allocator_for_env;
// Change the value of the env var |name|, leaking the original value.
// If |name_value| is NULL, the variable is deleted from the environment,
// otherwise the corresponding "NAME=value" string is replaced with
// |name_value|.
void LeakyResetEnv(const char *name, const char *name_value) {
char **env = GetEnviron();
uptr name_len = internal_strlen(name);
while (*env != 0) {
uptr len = internal_strlen(*env);
if (len > name_len) {
const char *p = *env;
if (!internal_memcmp(p, name, name_len) && p[name_len] == '=') {
// Match.
if (name_value) {
// Replace the old value with the new one.
*env = const_cast<char*>(name_value);
} else {
// Shift the subsequent pointers back.
char **del = env;
do {
del[0] = del[1];
} while (*del++);
}
}
}
env++;
}
}
SANITIZER_WEAK_CXX_DEFAULT_IMPL
bool ReexecDisabled() {
return false;
}
static bool DyldNeedsEnvVariable() {
// If running on OS X 10.11+ or iOS 9.0+, dyld will interpose even if
// DYLD_INSERT_LIBRARIES is not set.
return GetMacosAlignedVersion() < MacosVersion(10, 11);
}
void MaybeReexec() {
// FIXME: This should really live in some "InitializePlatform" method.
MonotonicNanoTime();
if (ReexecDisabled()) return;
// Make sure the dynamic runtime library is preloaded so that the
// wrappers work. If it is not, set DYLD_INSERT_LIBRARIES and re-exec
// ourselves.
Dl_info info;
RAW_CHECK(dladdr((void*)((uptr)&__sanitizer_report_error_summary), &info));
char *dyld_insert_libraries =
const_cast<char*>(GetEnv(kDyldInsertLibraries));
uptr old_env_len = dyld_insert_libraries ?
internal_strlen(dyld_insert_libraries) : 0;
uptr fname_len = internal_strlen(info.dli_fname);
const char *dylib_name = StripModuleName(info.dli_fname);
uptr dylib_name_len = internal_strlen(dylib_name);
bool lib_is_in_env = dyld_insert_libraries &&
internal_strstr(dyld_insert_libraries, dylib_name);
if (DyldNeedsEnvVariable() && !lib_is_in_env) {
// DYLD_INSERT_LIBRARIES is not set or does not contain the runtime
// library.
InternalScopedString program_name(1024);
uint32_t buf_size = program_name.size();
_NSGetExecutablePath(program_name.data(), &buf_size);
char *new_env = const_cast<char*>(info.dli_fname);
if (dyld_insert_libraries) {
// Append the runtime dylib name to the existing value of
// DYLD_INSERT_LIBRARIES.
new_env = (char*)allocator_for_env.Allocate(old_env_len + fname_len + 2);
internal_strncpy(new_env, dyld_insert_libraries, old_env_len);
new_env[old_env_len] = ':';
// Copy fname_len and add a trailing zero.
internal_strncpy(new_env + old_env_len + 1, info.dli_fname,
fname_len + 1);
// Ok to use setenv() since the wrappers don't depend on the value of
// asan_inited.
setenv(kDyldInsertLibraries, new_env, /*overwrite*/1);
} else {
// Set DYLD_INSERT_LIBRARIES equal to the runtime dylib name.
setenv(kDyldInsertLibraries, info.dli_fname, /*overwrite*/0);
}
VReport(1, "exec()-ing the program with\n");
VReport(1, "%s=%s\n", kDyldInsertLibraries, new_env);
VReport(1, "to enable wrappers.\n");
execv(program_name.data(), *_NSGetArgv());
// We get here only if execv() failed.
Report("ERROR: The process is launched without DYLD_INSERT_LIBRARIES, "
"which is required for the sanitizer to work. We tried to set the "
"environment variable and re-execute itself, but execv() failed, "
"possibly because of sandbox restrictions. Make sure to launch the "
"executable with:\n%s=%s\n", kDyldInsertLibraries, new_env);
RAW_CHECK("execv failed" && 0);
}
// Verify that interceptors really work. We'll use dlsym to locate
// "pthread_create", if interceptors are working, it should really point to
// "wrap_pthread_create" within our own dylib.
Dl_info info_pthread_create;
void *dlopen_addr = dlsym(RTLD_DEFAULT, "pthread_create");
RAW_CHECK(dladdr(dlopen_addr, &info_pthread_create));
if (internal_strcmp(info.dli_fname, info_pthread_create.dli_fname) != 0) {
Report(
"ERROR: Interceptors are not working. This may be because %s is "
"loaded too late (e.g. via dlopen). Please launch the executable "
"with:\n%s=%s\n",
SanitizerToolName, kDyldInsertLibraries, info.dli_fname);
RAW_CHECK("interceptors not installed" && 0);
}
if (!lib_is_in_env)
return;
if (!common_flags()->strip_env)
return;
// DYLD_INSERT_LIBRARIES is set and contains the runtime library. Let's remove
// the dylib from the environment variable, because interceptors are installed
// and we don't want our children to inherit the variable.
uptr env_name_len = internal_strlen(kDyldInsertLibraries);
// Allocate memory to hold the previous env var name, its value, the '='
// sign and the '\0' char.
char *new_env = (char*)allocator_for_env.Allocate(
old_env_len + 2 + env_name_len);
RAW_CHECK(new_env);
internal_memset(new_env, '\0', old_env_len + 2 + env_name_len);
internal_strncpy(new_env, kDyldInsertLibraries, env_name_len);
new_env[env_name_len] = '=';
char *new_env_pos = new_env + env_name_len + 1;
// Iterate over colon-separated pieces of |dyld_insert_libraries|.
char *piece_start = dyld_insert_libraries;
char *piece_end = NULL;
char *old_env_end = dyld_insert_libraries + old_env_len;
do {
if (piece_start[0] == ':') piece_start++;
piece_end = internal_strchr(piece_start, ':');
if (!piece_end) piece_end = dyld_insert_libraries + old_env_len;
if ((uptr)(piece_start - dyld_insert_libraries) > old_env_len) break;
uptr piece_len = piece_end - piece_start;
char *filename_start =
(char *)internal_memrchr(piece_start, '/', piece_len);
uptr filename_len = piece_len;
if (filename_start) {
filename_start += 1;
filename_len = piece_len - (filename_start - piece_start);
} else {
filename_start = piece_start;
}
// If the current piece isn't the runtime library name,
// append it to new_env.
if ((dylib_name_len != filename_len) ||
(internal_memcmp(filename_start, dylib_name, dylib_name_len) != 0)) {
if (new_env_pos != new_env + env_name_len + 1) {
new_env_pos[0] = ':';
new_env_pos++;
}
internal_strncpy(new_env_pos, piece_start, piece_len);
new_env_pos += piece_len;
}
// Move on to the next piece.
piece_start = piece_end;
} while (piece_start < old_env_end);
// Can't use setenv() here, because it requires the allocator to be
// initialized.
// FIXME: instead of filtering DYLD_INSERT_LIBRARIES here, do it in
// a separate function called after InitializeAllocator().
if (new_env_pos == new_env + env_name_len + 1) new_env = NULL;
LeakyResetEnv(kDyldInsertLibraries, new_env);
}
#endif // SANITIZER_GO
char **GetArgv() {
return *_NSGetArgv();
}
#if SANITIZER_IOS && !SANITIZER_IOSSIM
// The task_vm_info struct is normally provided by the macOS SDK, but we need
// fields only available in 10.12+. Declare the struct manually to be able to
// build against older SDKs.
struct __sanitizer_task_vm_info {
mach_vm_size_t virtual_size;
integer_t region_count;
integer_t page_size;
mach_vm_size_t resident_size;
mach_vm_size_t resident_size_peak;
mach_vm_size_t device;
mach_vm_size_t device_peak;
mach_vm_size_t internal;
mach_vm_size_t internal_peak;
mach_vm_size_t external;
mach_vm_size_t external_peak;
mach_vm_size_t reusable;
mach_vm_size_t reusable_peak;
mach_vm_size_t purgeable_volatile_pmap;
mach_vm_size_t purgeable_volatile_resident;
mach_vm_size_t purgeable_volatile_virtual;
mach_vm_size_t compressed;
mach_vm_size_t compressed_peak;
mach_vm_size_t compressed_lifetime;
mach_vm_size_t phys_footprint;
mach_vm_address_t min_address;
mach_vm_address_t max_address;
};
#define __SANITIZER_TASK_VM_INFO_COUNT ((mach_msg_type_number_t) \
(sizeof(__sanitizer_task_vm_info) / sizeof(natural_t)))
static uptr GetTaskInfoMaxAddress() {
__sanitizer_task_vm_info vm_info = {} /* zero initialize */;
mach_msg_type_number_t count = __SANITIZER_TASK_VM_INFO_COUNT;
int err = task_info(mach_task_self(), TASK_VM_INFO, (int *)&vm_info, &count);
return err ? 0 : vm_info.max_address;
}
uptr GetMaxUserVirtualAddress() {
static uptr max_vm = GetTaskInfoMaxAddress();
if (max_vm != 0)
return max_vm - 1;
// xnu cannot provide vm address limit
# if SANITIZER_WORDSIZE == 32
return 0xffe00000 - 1;
# else
return 0x200000000 - 1;
# endif
}
#else // !SANITIZER_IOS
uptr GetMaxUserVirtualAddress() {
# if SANITIZER_WORDSIZE == 64
return (1ULL << 47) - 1; // 0x00007fffffffffffUL;
# else // SANITIZER_WORDSIZE == 32
static_assert(SANITIZER_WORDSIZE == 32, "Wrong wordsize");
return (1ULL << 32) - 1; // 0xffffffff;
# endif
}
#endif
uptr GetMaxVirtualAddress() {
return GetMaxUserVirtualAddress();
}
uptr MapDynamicShadow(uptr shadow_size_bytes, uptr shadow_scale,
uptr min_shadow_base_alignment, uptr &high_mem_end) {
const uptr granularity = GetMmapGranularity();
const uptr alignment =
Max<uptr>(granularity << shadow_scale, 1ULL << min_shadow_base_alignment);
const uptr left_padding =
Max<uptr>(granularity, 1ULL << min_shadow_base_alignment);
uptr space_size = shadow_size_bytes + left_padding;
uptr largest_gap_found = 0;
uptr max_occupied_addr = 0;
VReport(2, "FindDynamicShadowStart, space_size = %p\n", space_size);
uptr shadow_start =
FindAvailableMemoryRange(space_size, alignment, granularity,
&largest_gap_found, &max_occupied_addr);
// If the shadow doesn't fit, restrict the address space to make it fit.
if (shadow_start == 0) {
VReport(
2,
"Shadow doesn't fit, largest_gap_found = %p, max_occupied_addr = %p\n",
largest_gap_found, max_occupied_addr);
uptr new_max_vm = RoundDownTo(largest_gap_found << shadow_scale, alignment);
if (new_max_vm < max_occupied_addr) {
Report("Unable to find a memory range for dynamic shadow.\n");
Report(
"space_size = %p, largest_gap_found = %p, max_occupied_addr = %p, "
"new_max_vm = %p\n",
space_size, largest_gap_found, max_occupied_addr, new_max_vm);
CHECK(0 && "cannot place shadow");
}
RestrictMemoryToMaxAddress(new_max_vm);
high_mem_end = new_max_vm - 1;
space_size = (high_mem_end >> shadow_scale) + left_padding;
VReport(2, "FindDynamicShadowStart, space_size = %p\n", space_size);
shadow_start = FindAvailableMemoryRange(space_size, alignment, granularity,
nullptr, nullptr);
if (shadow_start == 0) {
Report("Unable to find a memory range after restricting VM.\n");
CHECK(0 && "cannot place shadow after restricting vm");
}
}
CHECK_NE((uptr)0, shadow_start);
CHECK(IsAligned(shadow_start, alignment));
return shadow_start;
}
uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
uptr *largest_gap_found,
uptr *max_occupied_addr) {
typedef vm_region_submap_short_info_data_64_t RegionInfo;
enum { kRegionInfoSize = VM_REGION_SUBMAP_SHORT_INFO_COUNT_64 };
// Start searching for available memory region past PAGEZERO, which is
// 4KB on 32-bit and 4GB on 64-bit.
mach_vm_address_t start_address =
(SANITIZER_WORDSIZE == 32) ? 0x000000001000 : 0x000100000000;
mach_vm_address_t address = start_address;
mach_vm_address_t free_begin = start_address;
kern_return_t kr = KERN_SUCCESS;
if (largest_gap_found) *largest_gap_found = 0;
if (max_occupied_addr) *max_occupied_addr = 0;
while (kr == KERN_SUCCESS) {
mach_vm_size_t vmsize = 0;
natural_t depth = 0;
RegionInfo vminfo;
mach_msg_type_number_t count = kRegionInfoSize;
kr = mach_vm_region_recurse(mach_task_self(), &address, &vmsize, &depth,
(vm_region_info_t)&vminfo, &count);
if (kr == KERN_INVALID_ADDRESS) {
// No more regions beyond "address", consider the gap at the end of VM.
address = GetMaxVirtualAddress() + 1;
vmsize = 0;
} else {
if (max_occupied_addr) *max_occupied_addr = address + vmsize;
}
if (free_begin != address) {
// We found a free region [free_begin..address-1].
uptr gap_start = RoundUpTo((uptr)free_begin + left_padding, alignment);
uptr gap_end = RoundDownTo((uptr)address, alignment);
uptr gap_size = gap_end > gap_start ? gap_end - gap_start : 0;
if (size < gap_size) {
return gap_start;
}
if (largest_gap_found && *largest_gap_found < gap_size) {
*largest_gap_found = gap_size;
}
}
// Move to the next region.
address += vmsize;
free_begin = address;
}
// We looked at all free regions and could not find one large enough.
return 0;
}
// FIXME implement on this platform.
void GetMemoryProfile(fill_profile_f cb, uptr *stats, uptr stats_size) { }
void SignalContext::DumpAllRegisters(void *context) {
Report("Register values:\n");
ucontext_t *ucontext = (ucontext_t*)context;
# define DUMPREG64(r) \
Printf("%s = 0x%016llx ", #r, ucontext->uc_mcontext->__ss.__ ## r);
# define DUMPREGA64(r) \
Printf(" %s = 0x%016llx ", #r, AARCH64_GET_REG(r));
# define DUMPREG32(r) \
Printf("%s = 0x%08x ", #r, ucontext->uc_mcontext->__ss.__ ## r);
# define DUMPREG_(r) Printf(" "); DUMPREG(r);
# define DUMPREG__(r) Printf(" "); DUMPREG(r);
# define DUMPREG___(r) Printf(" "); DUMPREG(r);
# if defined(__x86_64__)
# define DUMPREG(r) DUMPREG64(r)
DUMPREG(rax); DUMPREG(rbx); DUMPREG(rcx); DUMPREG(rdx); Printf("\n");
DUMPREG(rdi); DUMPREG(rsi); DUMPREG(rbp); DUMPREG(rsp); Printf("\n");
DUMPREG_(r8); DUMPREG_(r9); DUMPREG(r10); DUMPREG(r11); Printf("\n");
DUMPREG(r12); DUMPREG(r13); DUMPREG(r14); DUMPREG(r15); Printf("\n");
# elif defined(__i386__)
# define DUMPREG(r) DUMPREG32(r)
DUMPREG(eax); DUMPREG(ebx); DUMPREG(ecx); DUMPREG(edx); Printf("\n");
DUMPREG(edi); DUMPREG(esi); DUMPREG(ebp); DUMPREG(esp); Printf("\n");
# elif defined(__aarch64__)
# define DUMPREG(r) DUMPREG64(r)
DUMPREG_(x[0]); DUMPREG_(x[1]); DUMPREG_(x[2]); DUMPREG_(x[3]); Printf("\n");
DUMPREG_(x[4]); DUMPREG_(x[5]); DUMPREG_(x[6]); DUMPREG_(x[7]); Printf("\n");
DUMPREG_(x[8]); DUMPREG_(x[9]); DUMPREG(x[10]); DUMPREG(x[11]); Printf("\n");
DUMPREG(x[12]); DUMPREG(x[13]); DUMPREG(x[14]); DUMPREG(x[15]); Printf("\n");
DUMPREG(x[16]); DUMPREG(x[17]); DUMPREG(x[18]); DUMPREG(x[19]); Printf("\n");
DUMPREG(x[20]); DUMPREG(x[21]); DUMPREG(x[22]); DUMPREG(x[23]); Printf("\n");
DUMPREG(x[24]); DUMPREG(x[25]); DUMPREG(x[26]); DUMPREG(x[27]); Printf("\n");
DUMPREG(x[28]); DUMPREGA64(fp); DUMPREGA64(lr); DUMPREGA64(sp); Printf("\n");
# elif defined(__arm__)
# define DUMPREG(r) DUMPREG32(r)
DUMPREG_(r[0]); DUMPREG_(r[1]); DUMPREG_(r[2]); DUMPREG_(r[3]); Printf("\n");
DUMPREG_(r[4]); DUMPREG_(r[5]); DUMPREG_(r[6]); DUMPREG_(r[7]); Printf("\n");
DUMPREG_(r[8]); DUMPREG_(r[9]); DUMPREG(r[10]); DUMPREG(r[11]); Printf("\n");
DUMPREG(r[12]); DUMPREG___(sp); DUMPREG___(lr); DUMPREG___(pc); Printf("\n");
# else
# error "Unknown architecture"
# endif
# undef DUMPREG64
# undef DUMPREG32
# undef DUMPREG_
# undef DUMPREG__
# undef DUMPREG___
# undef DUMPREG
}
static inline bool CompareBaseAddress(const LoadedModule &a,
const LoadedModule &b) {
return a.base_address() < b.base_address();
}
void FormatUUID(char *out, uptr size, const u8 *uuid) {
internal_snprintf(out, size,
"<%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-"
"%02X%02X%02X%02X%02X%02X>",
uuid[0], uuid[1], uuid[2], uuid[3], uuid[4], uuid[5],
uuid[6], uuid[7], uuid[8], uuid[9], uuid[10], uuid[11],
uuid[12], uuid[13], uuid[14], uuid[15]);
}
void DumpProcessMap() {
Printf("Process module map:\n");
MemoryMappingLayout memory_mapping(false);
InternalMmapVector<LoadedModule> modules;
modules.reserve(128);
memory_mapping.DumpListOfModules(&modules);
Sort(modules.data(), modules.size(), CompareBaseAddress);
for (uptr i = 0; i < modules.size(); ++i) {
char uuid_str[128];
FormatUUID(uuid_str, sizeof(uuid_str), modules[i].uuid());
Printf("0x%zx-0x%zx %s (%s) %s\n", modules[i].base_address(),
modules[i].max_executable_address(), modules[i].full_name(),
ModuleArchToString(modules[i].arch()), uuid_str);
}
Printf("End of module map.\n");
}
void CheckNoDeepBind(const char *filename, int flag) {
// Do nothing.
}
bool GetRandom(void *buffer, uptr length, bool blocking) {
if (!buffer || !length || length > 256)
return false;
// arc4random never fails.
REAL(arc4random_buf)(buffer, length);
return true;
}
u32 GetNumberOfCPUs() {
return (u32)sysconf(_SC_NPROCESSORS_ONLN);
}
void InitializePlatformCommonFlags(CommonFlags *cf) {}
} // namespace __sanitizer
#endif // SANITIZER_MAC