//===-- asan_rtl.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 AddressSanitizer, an address sanity checker.
//
// Main file of the ASan run-time library.
//===----------------------------------------------------------------------===//
#include "asan_activation.h"
#include "asan_allocator.h"
#include "asan_interceptors.h"
#include "asan_interface_internal.h"
#include "asan_internal.h"
#include "asan_mapping.h"
#include "asan_poisoning.h"
#include "asan_report.h"
#include "asan_stack.h"
#include "asan_stats.h"
#include "asan_suppressions.h"
#include "asan_thread.h"
#include "sanitizer_common/sanitizer_atomic.h"
#include "sanitizer_common/sanitizer_flags.h"
#include "sanitizer_common/sanitizer_libc.h"
#include "sanitizer_common/sanitizer_symbolizer.h"
#include "lsan/lsan_common.h"
#include "ubsan/ubsan_init.h"
#include "ubsan/ubsan_platform.h"
uptr __asan_shadow_memory_dynamic_address; // Global interface symbol.
int __asan_option_detect_stack_use_after_return; // Global interface symbol.
uptr *__asan_test_only_reported_buggy_pointer; // Used only for testing asan.
namespace __asan {
uptr AsanMappingProfile[kAsanMappingProfileSize];
static void AsanDie() {
static atomic_uint32_t num_calls;
if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
// Don't die twice - run a busy loop.
while (1) { }
}
if (common_flags()->print_module_map >= 1) PrintModuleMap();
if (flags()->sleep_before_dying) {
Report("Sleeping for %d second(s)\n", flags()->sleep_before_dying);
SleepForSeconds(flags()->sleep_before_dying);
}
if (flags()->unmap_shadow_on_exit) {
if (kMidMemBeg) {
UnmapOrDie((void*)kLowShadowBeg, kMidMemBeg - kLowShadowBeg);
UnmapOrDie((void*)kMidMemEnd, kHighShadowEnd - kMidMemEnd);
} else {
if (kHighShadowEnd)
UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
}
}
}
static void AsanCheckFailed(const char *file, int line, const char *cond,
u64 v1, u64 v2) {
Report("AddressSanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
line, cond, (uptr)v1, (uptr)v2);
// Print a stack trace the first time we come here. Otherwise, we probably
// failed a CHECK during symbolization.
static atomic_uint32_t num_calls;
if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) == 0) {
PRINT_CURRENT_STACK_CHECK();
}
Die();
}
// -------------------------- Globals --------------------- {{{1
int asan_inited;
bool asan_init_is_running;
#if !ASAN_FIXED_MAPPING
uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
#endif
// -------------------------- Misc ---------------- {{{1
void ShowStatsAndAbort() {
__asan_print_accumulated_stats();
Die();
}
// --------------- LowLevelAllocateCallbac ---------- {{{1
static void OnLowLevelAllocate(uptr ptr, uptr size) {
PoisonShadow(ptr, size, kAsanInternalHeapMagic);
}
// -------------------------- Run-time entry ------------------- {{{1
// exported functions
#define ASAN_REPORT_ERROR(type, is_write, size) \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_report_ ## type ## size(uptr addr) { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true); \
} \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_report_exp_ ## type ## size(uptr addr, u32 exp) { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true); \
} \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_report_ ## type ## size ## _noabort(uptr addr) { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false); \
} \
ASAN_REPORT_ERROR(load, false, 1)
ASAN_REPORT_ERROR(load, false, 2)
ASAN_REPORT_ERROR(load, false, 4)
ASAN_REPORT_ERROR(load, false, 8)
ASAN_REPORT_ERROR(load, false, 16)
ASAN_REPORT_ERROR(store, true, 1)
ASAN_REPORT_ERROR(store, true, 2)
ASAN_REPORT_ERROR(store, true, 4)
ASAN_REPORT_ERROR(store, true, 8)
ASAN_REPORT_ERROR(store, true, 16)
#define ASAN_REPORT_ERROR_N(type, is_write) \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_report_ ## type ## _n(uptr addr, uptr size) { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, 0, true); \
} \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_report_exp_ ## type ## _n(uptr addr, uptr size, u32 exp) { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, exp, true); \
} \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_report_ ## type ## _n_noabort(uptr addr, uptr size) { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, 0, false); \
} \
ASAN_REPORT_ERROR_N(load, false)
ASAN_REPORT_ERROR_N(store, true)
#define ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp_arg, fatal) \
if (SANITIZER_MYRIAD2 && !AddrIsInMem(addr) && !AddrIsInShadow(addr)) \
return; \
uptr sp = MEM_TO_SHADOW(addr); \
uptr s = size <= SHADOW_GRANULARITY ? *reinterpret_cast<u8 *>(sp) \
: *reinterpret_cast<u16 *>(sp); \
if (UNLIKELY(s)) { \
if (UNLIKELY(size >= SHADOW_GRANULARITY || \
((s8)((addr & (SHADOW_GRANULARITY - 1)) + size - 1)) >= \
(s8)s)) { \
if (__asan_test_only_reported_buggy_pointer) { \
*__asan_test_only_reported_buggy_pointer = addr; \
} else { \
GET_CALLER_PC_BP_SP; \
ReportGenericError(pc, bp, sp, addr, is_write, size, exp_arg, \
fatal); \
} \
} \
}
#define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size) \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_##type##size(uptr addr) { \
ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, true) \
} \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_exp_##type##size(uptr addr, u32 exp) { \
ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, exp, true) \
} \
extern "C" NOINLINE INTERFACE_ATTRIBUTE \
void __asan_##type##size ## _noabort(uptr addr) { \
ASAN_MEMORY_ACCESS_CALLBACK_BODY(type, is_write, size, 0, false) \
} \
ASAN_MEMORY_ACCESS_CALLBACK(load, false, 1)
ASAN_MEMORY_ACCESS_CALLBACK(load, false, 2)
ASAN_MEMORY_ACCESS_CALLBACK(load, false, 4)
ASAN_MEMORY_ACCESS_CALLBACK(load, false, 8)
ASAN_MEMORY_ACCESS_CALLBACK(load, false, 16)
ASAN_MEMORY_ACCESS_CALLBACK(store, true, 1)
ASAN_MEMORY_ACCESS_CALLBACK(store, true, 2)
ASAN_MEMORY_ACCESS_CALLBACK(store, true, 4)
ASAN_MEMORY_ACCESS_CALLBACK(store, true, 8)
ASAN_MEMORY_ACCESS_CALLBACK(store, true, 16)
extern "C"
NOINLINE INTERFACE_ATTRIBUTE
void __asan_loadN(uptr addr, uptr size) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
ReportGenericError(pc, bp, sp, addr, false, size, 0, true);
}
}
extern "C"
NOINLINE INTERFACE_ATTRIBUTE
void __asan_exp_loadN(uptr addr, uptr size, u32 exp) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
ReportGenericError(pc, bp, sp, addr, false, size, exp, true);
}
}
extern "C"
NOINLINE INTERFACE_ATTRIBUTE
void __asan_loadN_noabort(uptr addr, uptr size) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
ReportGenericError(pc, bp, sp, addr, false, size, 0, false);
}
}
extern "C"
NOINLINE INTERFACE_ATTRIBUTE
void __asan_storeN(uptr addr, uptr size) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
ReportGenericError(pc, bp, sp, addr, true, size, 0, true);
}
}
extern "C"
NOINLINE INTERFACE_ATTRIBUTE
void __asan_exp_storeN(uptr addr, uptr size, u32 exp) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
ReportGenericError(pc, bp, sp, addr, true, size, exp, true);
}
}
extern "C"
NOINLINE INTERFACE_ATTRIBUTE
void __asan_storeN_noabort(uptr addr, uptr size) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
ReportGenericError(pc, bp, sp, addr, true, size, 0, false);
}
}
// Force the linker to keep the symbols for various ASan interface functions.
// We want to keep those in the executable in order to let the instrumented
// dynamic libraries access the symbol even if it is not used by the executable
// itself. This should help if the build system is removing dead code at link
// time.
static NOINLINE void force_interface_symbols() {
volatile int fake_condition = 0; // prevent dead condition elimination.
// __asan_report_* functions are noreturn, so we need a switch to prevent
// the compiler from removing any of them.
// clang-format off
switch (fake_condition) {
case 1: __asan_report_load1(0); break;
case 2: __asan_report_load2(0); break;
case 3: __asan_report_load4(0); break;
case 4: __asan_report_load8(0); break;
case 5: __asan_report_load16(0); break;
case 6: __asan_report_load_n(0, 0); break;
case 7: __asan_report_store1(0); break;
case 8: __asan_report_store2(0); break;
case 9: __asan_report_store4(0); break;
case 10: __asan_report_store8(0); break;
case 11: __asan_report_store16(0); break;
case 12: __asan_report_store_n(0, 0); break;
case 13: __asan_report_exp_load1(0, 0); break;
case 14: __asan_report_exp_load2(0, 0); break;
case 15: __asan_report_exp_load4(0, 0); break;
case 16: __asan_report_exp_load8(0, 0); break;
case 17: __asan_report_exp_load16(0, 0); break;
case 18: __asan_report_exp_load_n(0, 0, 0); break;
case 19: __asan_report_exp_store1(0, 0); break;
case 20: __asan_report_exp_store2(0, 0); break;
case 21: __asan_report_exp_store4(0, 0); break;
case 22: __asan_report_exp_store8(0, 0); break;
case 23: __asan_report_exp_store16(0, 0); break;
case 24: __asan_report_exp_store_n(0, 0, 0); break;
case 25: __asan_register_globals(nullptr, 0); break;
case 26: __asan_unregister_globals(nullptr, 0); break;
case 27: __asan_set_death_callback(nullptr); break;
case 28: __asan_set_error_report_callback(nullptr); break;
case 29: __asan_handle_no_return(); break;
case 30: __asan_address_is_poisoned(nullptr); break;
case 31: __asan_poison_memory_region(nullptr, 0); break;
case 32: __asan_unpoison_memory_region(nullptr, 0); break;
case 34: __asan_before_dynamic_init(nullptr); break;
case 35: __asan_after_dynamic_init(); break;
case 36: __asan_poison_stack_memory(0, 0); break;
case 37: __asan_unpoison_stack_memory(0, 0); break;
case 38: __asan_region_is_poisoned(0, 0); break;
case 39: __asan_describe_address(0); break;
case 40: __asan_set_shadow_00(0, 0); break;
case 41: __asan_set_shadow_f1(0, 0); break;
case 42: __asan_set_shadow_f2(0, 0); break;
case 43: __asan_set_shadow_f3(0, 0); break;
case 44: __asan_set_shadow_f5(0, 0); break;
case 45: __asan_set_shadow_f8(0, 0); break;
}
// clang-format on
}
static void asan_atexit() {
Printf("AddressSanitizer exit stats:\n");
__asan_print_accumulated_stats();
// Print AsanMappingProfile.
for (uptr i = 0; i < kAsanMappingProfileSize; i++) {
if (AsanMappingProfile[i] == 0) continue;
Printf("asan_mapping.h:%zd -- %zd\n", i, AsanMappingProfile[i]);
}
}
static void InitializeHighMemEnd() {
#if !SANITIZER_MYRIAD2
#if !ASAN_FIXED_MAPPING
kHighMemEnd = GetMaxUserVirtualAddress();
// Increase kHighMemEnd to make sure it's properly
// aligned together with kHighMemBeg:
kHighMemEnd |= SHADOW_GRANULARITY * GetMmapGranularity() - 1;
#endif // !ASAN_FIXED_MAPPING
CHECK_EQ((kHighMemBeg % GetMmapGranularity()), 0);
#endif // !SANITIZER_MYRIAD2
}
void PrintAddressSpaceLayout() {
if (kHighMemBeg) {
Printf("|| `[%p, %p]` || HighMem ||\n",
(void*)kHighMemBeg, (void*)kHighMemEnd);
Printf("|| `[%p, %p]` || HighShadow ||\n",
(void*)kHighShadowBeg, (void*)kHighShadowEnd);
}
if (kMidMemBeg) {
Printf("|| `[%p, %p]` || ShadowGap3 ||\n",
(void*)kShadowGap3Beg, (void*)kShadowGap3End);
Printf("|| `[%p, %p]` || MidMem ||\n",
(void*)kMidMemBeg, (void*)kMidMemEnd);
Printf("|| `[%p, %p]` || ShadowGap2 ||\n",
(void*)kShadowGap2Beg, (void*)kShadowGap2End);
Printf("|| `[%p, %p]` || MidShadow ||\n",
(void*)kMidShadowBeg, (void*)kMidShadowEnd);
}
Printf("|| `[%p, %p]` || ShadowGap ||\n",
(void*)kShadowGapBeg, (void*)kShadowGapEnd);
if (kLowShadowBeg) {
Printf("|| `[%p, %p]` || LowShadow ||\n",
(void*)kLowShadowBeg, (void*)kLowShadowEnd);
Printf("|| `[%p, %p]` || LowMem ||\n",
(void*)kLowMemBeg, (void*)kLowMemEnd);
}
Printf("MemToShadow(shadow): %p %p",
(void*)MEM_TO_SHADOW(kLowShadowBeg),
(void*)MEM_TO_SHADOW(kLowShadowEnd));
if (kHighMemBeg) {
Printf(" %p %p",
(void*)MEM_TO_SHADOW(kHighShadowBeg),
(void*)MEM_TO_SHADOW(kHighShadowEnd));
}
if (kMidMemBeg) {
Printf(" %p %p",
(void*)MEM_TO_SHADOW(kMidShadowBeg),
(void*)MEM_TO_SHADOW(kMidShadowEnd));
}
Printf("\n");
Printf("redzone=%zu\n", (uptr)flags()->redzone);
Printf("max_redzone=%zu\n", (uptr)flags()->max_redzone);
Printf("quarantine_size_mb=%zuM\n", (uptr)flags()->quarantine_size_mb);
Printf("thread_local_quarantine_size_kb=%zuK\n",
(uptr)flags()->thread_local_quarantine_size_kb);
Printf("malloc_context_size=%zu\n",
(uptr)common_flags()->malloc_context_size);
Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
if (kMidMemBeg)
CHECK(kMidShadowBeg > kLowShadowEnd &&
kMidMemBeg > kMidShadowEnd &&
kHighShadowBeg > kMidMemEnd);
}
static void AsanInitInternal() {
if (LIKELY(asan_inited)) return;
SanitizerToolName = "AddressSanitizer";
CHECK(!asan_init_is_running && "ASan init calls itself!");
asan_init_is_running = true;
CacheBinaryName();
CheckASLR();
// Initialize flags. This must be done early, because most of the
// initialization steps look at flags().
InitializeFlags();
AsanCheckIncompatibleRT();
AsanCheckDynamicRTPrereqs();
AvoidCVE_2016_2143();
SetCanPoisonMemory(flags()->poison_heap);
SetMallocContextSize(common_flags()->malloc_context_size);
InitializePlatformExceptionHandlers();
InitializeHighMemEnd();
// Make sure we are not statically linked.
AsanDoesNotSupportStaticLinkage();
// Install tool-specific callbacks in sanitizer_common.
AddDieCallback(AsanDie);
SetCheckFailedCallback(AsanCheckFailed);
SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
__sanitizer_set_report_path(common_flags()->log_path);
__asan_option_detect_stack_use_after_return =
flags()->detect_stack_use_after_return;
// Re-exec ourselves if we need to set additional env or command line args.
MaybeReexec();
// Setup internal allocator callback.
SetLowLevelAllocateMinAlignment(SHADOW_GRANULARITY);
SetLowLevelAllocateCallback(OnLowLevelAllocate);
InitializeAsanInterceptors();
// Enable system log ("adb logcat") on Android.
// Doing this before interceptors are initialized crashes in:
// AsanInitInternal -> android_log_write -> __interceptor_strcmp
AndroidLogInit();
ReplaceSystemMalloc();
DisableCoreDumperIfNecessary();
InitializeShadowMemory();
AsanTSDInit(PlatformTSDDtor);
InstallDeadlySignalHandlers(AsanOnDeadlySignal);
AllocatorOptions allocator_options;
allocator_options.SetFrom(flags(), common_flags());
InitializeAllocator(allocator_options);
MaybeStartBackgroudThread();
SetSoftRssLimitExceededCallback(AsanSoftRssLimitExceededCallback);
// On Linux AsanThread::ThreadStart() calls malloc() that's why asan_inited
// should be set to 1 prior to initializing the threads.
asan_inited = 1;
asan_init_is_running = false;
if (flags()->atexit)
Atexit(asan_atexit);
InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
// Now that ASan runtime is (mostly) initialized, deactivate it if
// necessary, so that it can be re-activated when requested.
if (flags()->start_deactivated)
AsanDeactivate();
// interceptors
InitTlsSize();
// Create main thread.
AsanThread *main_thread = CreateMainThread();
CHECK_EQ(0, main_thread->tid());
force_interface_symbols(); // no-op.
SanitizerInitializeUnwinder();
if (CAN_SANITIZE_LEAKS) {
__lsan::InitCommonLsan();
if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
if (flags()->halt_on_error)
Atexit(__lsan::DoLeakCheck);
else
Atexit(__lsan::DoRecoverableLeakCheckVoid);
}
}
#if CAN_SANITIZE_UB
__ubsan::InitAsPlugin();
#endif
InitializeSuppressions();
if (CAN_SANITIZE_LEAKS) {
// LateInitialize() calls dlsym, which can allocate an error string buffer
// in the TLS. Let's ignore the allocation to avoid reporting a leak.
__lsan::ScopedInterceptorDisabler disabler;
Symbolizer::LateInitialize();
} else {
Symbolizer::LateInitialize();
}
VReport(1, "AddressSanitizer Init done\n");
if (flags()->sleep_after_init) {
Report("Sleeping for %d second(s)\n", flags()->sleep_after_init);
SleepForSeconds(flags()->sleep_after_init);
}
}
// Initialize as requested from some part of ASan runtime library (interceptors,
// allocator, etc).
void AsanInitFromRtl() {
AsanInitInternal();
}
#if ASAN_DYNAMIC
// Initialize runtime in case it's LD_PRELOAD-ed into unsanitized executable
// (and thus normal initializers from .preinit_array or modules haven't run).
class AsanInitializer {
public: // NOLINT
AsanInitializer() {
AsanInitFromRtl();
}
};
static AsanInitializer asan_initializer;
#endif // ASAN_DYNAMIC
} // namespace __asan
// ---------------------- Interface ---------------- {{{1
using namespace __asan; // NOLINT
void NOINLINE __asan_handle_no_return() {
if (asan_init_is_running)
return;
int local_stack;
AsanThread *curr_thread = GetCurrentThread();
uptr PageSize = GetPageSizeCached();
uptr top, bottom;
if (curr_thread) {
top = curr_thread->stack_top();
bottom = ((uptr)&local_stack - PageSize) & ~(PageSize - 1);
} else if (SANITIZER_RTEMS) {
// Give up On RTEMS.
return;
} else {
CHECK(!SANITIZER_FUCHSIA);
// If we haven't seen this thread, try asking the OS for stack bounds.
uptr tls_addr, tls_size, stack_size;
GetThreadStackAndTls(/*main=*/false, &bottom, &stack_size, &tls_addr,
&tls_size);
top = bottom + stack_size;
}
static const uptr kMaxExpectedCleanupSize = 64 << 20; // 64M
if (top - bottom > kMaxExpectedCleanupSize) {
static bool reported_warning = false;
if (reported_warning)
return;
reported_warning = true;
Report("WARNING: ASan is ignoring requested __asan_handle_no_return: "
"stack top: %p; bottom %p; size: %p (%zd)\n"
"False positive error reports may follow\n"
"For details see "
"https://github.com/google/sanitizers/issues/189\n",
top, bottom, top - bottom, top - bottom);
return;
}
PoisonShadow(bottom, top - bottom, 0);
if (curr_thread && curr_thread->has_fake_stack())
curr_thread->fake_stack()->HandleNoReturn();
}
void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
SetUserDieCallback(callback);
}
// Initialize as requested from instrumented application code.
// We use this call as a trigger to wake up ASan from deactivated state.
void __asan_init() {
AsanActivate();
AsanInitInternal();
}
void __asan_version_mismatch_check() {
// Do nothing.
}
