gcc/libsanitizer/asan/asan_rtl.cc
Kostya Serebryany dee5ea7a0b libsanitizer merge from upstream r209283
From-SVN: r210743
2014-05-22 07:09:21 +00:00

772 lines
29 KiB
C++

//===-- asan_rtl.cc -------------------------------------------------------===//
//
// 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_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"
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 (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 {
UnmapOrDie((void*)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
}
}
if (common_flags()->coverage)
__sanitizer_cov_dump();
if (death_callback)
death_callback();
if (flags()->abort_on_error)
Abort();
internal__exit(flags()->exitcode);
}
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);
// FIXME: check for infinite recursion without a thread-local counter here.
PRINT_CURRENT_STACK();
Die();
}
// -------------------------- Flags ------------------------- {{{1
static const int kDefaultMallocContextSize = 30;
Flags asan_flags_dont_use_directly; // use via flags().
static const char *MaybeCallAsanDefaultOptions() {
return (&__asan_default_options) ? __asan_default_options() : "";
}
static const char *MaybeUseAsanDefaultOptionsCompileDefinition() {
#ifdef ASAN_DEFAULT_OPTIONS
// Stringize the macro value.
# define ASAN_STRINGIZE(x) #x
# define ASAN_STRINGIZE_OPTIONS(options) ASAN_STRINGIZE(options)
return ASAN_STRINGIZE_OPTIONS(ASAN_DEFAULT_OPTIONS);
#else
return "";
#endif
}
static void ParseFlagsFromString(Flags *f, const char *str) {
CommonFlags *cf = common_flags();
ParseCommonFlagsFromString(cf, str);
CHECK((uptr)cf->malloc_context_size <= kStackTraceMax);
// Please write meaningful flag descriptions when adding new flags.
ParseFlag(str, &f->quarantine_size, "quarantine_size",
"Size (in bytes) of quarantine used to detect use-after-free "
"errors. Lower value may reduce memory usage but increase the "
"chance of false negatives.");
ParseFlag(str, &f->redzone, "redzone",
"Minimal size (in bytes) of redzones around heap objects. "
"Requirement: redzone >= 16, is a power of two.");
ParseFlag(str, &f->max_redzone, "max_redzone",
"Maximal size (in bytes) of redzones around heap objects.");
CHECK_GE(f->redzone, 16);
CHECK_GE(f->max_redzone, f->redzone);
CHECK_LE(f->max_redzone, 2048);
CHECK(IsPowerOfTwo(f->redzone));
CHECK(IsPowerOfTwo(f->max_redzone));
ParseFlag(str, &f->debug, "debug",
"If set, prints some debugging information and does additional checks.");
ParseFlag(str, &f->report_globals, "report_globals",
"Controls the way to handle globals (0 - don't detect buffer overflow on "
"globals, 1 - detect buffer overflow, 2 - print data about registered "
"globals).");
ParseFlag(str, &f->check_initialization_order,
"check_initialization_order",
"If set, attempts to catch initialization order issues.");
ParseFlag(str, &f->replace_str, "replace_str",
"If set, uses custom wrappers and replacements for libc string functions "
"to find more errors.");
ParseFlag(str, &f->replace_intrin, "replace_intrin",
"If set, uses custom wrappers for memset/memcpy/memmove intinsics.");
ParseFlag(str, &f->mac_ignore_invalid_free, "mac_ignore_invalid_free",
"Ignore invalid free() calls to work around some bugs. Used on OS X "
"only.");
ParseFlag(str, &f->detect_stack_use_after_return,
"detect_stack_use_after_return",
"Enables stack-use-after-return checking at run-time.");
ParseFlag(str, &f->min_uar_stack_size_log, "min_uar_stack_size_log",
"Minimum fake stack size log.");
ParseFlag(str, &f->max_uar_stack_size_log, "max_uar_stack_size_log",
"Maximum fake stack size log.");
ParseFlag(str, &f->uar_noreserve, "uar_noreserve",
"Use mmap with 'norserve' flag to allocate fake stack.");
ParseFlag(str, &f->max_malloc_fill_size, "max_malloc_fill_size",
"ASan allocator flag. max_malloc_fill_size is the maximal amount of "
"bytes that will be filled with malloc_fill_byte on malloc.");
ParseFlag(str, &f->malloc_fill_byte, "malloc_fill_byte",
"Value used to fill the newly allocated memory.");
ParseFlag(str, &f->exitcode, "exitcode",
"Override the program exit status if the tool found an error.");
ParseFlag(str, &f->allow_user_poisoning, "allow_user_poisoning",
"If set, user may manually mark memory regions as poisoned or "
"unpoisoned.");
ParseFlag(str, &f->sleep_before_dying, "sleep_before_dying",
"Number of seconds to sleep between printing an error report and "
"terminating the program. Useful for debugging purposes (e.g. when one "
"needs to attach gdb).");
ParseFlag(str, &f->check_malloc_usable_size, "check_malloc_usable_size",
"Allows the users to work around the bug in Nvidia drivers prior to "
"295.*.");
ParseFlag(str, &f->unmap_shadow_on_exit, "unmap_shadow_on_exit",
"If set, explicitly unmaps the (huge) shadow at exit.");
ParseFlag(str, &f->abort_on_error, "abort_on_error",
"If set, the tool calls abort() instead of _exit() after printing the "
"error report.");
ParseFlag(str, &f->print_stats, "print_stats",
"Print various statistics after printing an error message or if "
"atexit=1.");
ParseFlag(str, &f->print_legend, "print_legend",
"Print the legend for the shadow bytes.");
ParseFlag(str, &f->atexit, "atexit",
"If set, prints ASan exit stats even after program terminates "
"successfully.");
ParseFlag(str, &f->disable_core, "disable_core",
"Disable core dumping. By default, disable_core=1 on 64-bit to avoid "
"dumping a 16T+ core file. "
"Ignored on OSes that don't dump core by default.");
ParseFlag(str, &f->allow_reexec, "allow_reexec",
"Allow the tool to re-exec the program. This may interfere badly with "
"the debugger.");
ParseFlag(str, &f->print_full_thread_history,
"print_full_thread_history",
"If set, prints thread creation stacks for the threads involved in the "
"report and their ancestors up to the main thread.");
ParseFlag(str, &f->poison_heap, "poison_heap",
"Poison (or not) the heap memory on [de]allocation. Zero value is useful "
"for benchmarking the allocator or instrumentator.");
ParseFlag(str, &f->poison_partial, "poison_partial",
"If true, poison partially addressable 8-byte aligned words "
"(default=true). This flag affects heap and global buffers, but not "
"stack buffers.");
ParseFlag(str, &f->alloc_dealloc_mismatch, "alloc_dealloc_mismatch",
"Report errors on malloc/delete, new/free, new/delete[], etc.");
ParseFlag(str, &f->strict_memcmp, "strict_memcmp",
"If true, assume that memcmp(p1, p2, n) always reads n bytes before "
"comparing p1 and p2.");
ParseFlag(str, &f->strict_init_order, "strict_init_order",
"If true, assume that dynamic initializers can never access globals from "
"other modules, even if the latter are already initialized.");
ParseFlag(str, &f->start_deactivated, "start_deactivated",
"If true, ASan tweaks a bunch of other flags (quarantine, redzone, heap "
"poisoning) to reduce memory consumption as much as possible, and "
"restores them to original values when the first instrumented module is "
"loaded into the process. This is mainly intended to be used on "
"Android. ");
ParseFlag(str, &f->detect_invalid_pointer_pairs,
"detect_invalid_pointer_pairs",
"If non-zero, try to detect operations like <, <=, >, >= and - on "
"invalid pointer pairs (e.g. when pointers belong to different objects). "
"The bigger the value the harder we try.");
ParseFlag(str, &f->detect_container_overflow,
"detect_container_overflow",
"If true, honor the container overflow annotations. "
"See https://code.google.com/p/address-sanitizer/wiki/ContainerOverflow");
ParseFlag(str, &f->detect_odr_violation, "detect_odr_violation",
"If >=2, detect violation of One-Definition-Rule (ODR); "
"If ==1, detect ODR-violation only if the two variables "
"have different sizes");
}
void InitializeFlags(Flags *f, const char *env) {
CommonFlags *cf = common_flags();
SetCommonFlagsDefaults(cf);
cf->detect_leaks = CAN_SANITIZE_LEAKS;
cf->external_symbolizer_path = GetEnv("ASAN_SYMBOLIZER_PATH");
cf->malloc_context_size = kDefaultMallocContextSize;
cf->intercept_tls_get_addr = true;
cf->coverage = false;
internal_memset(f, 0, sizeof(*f));
f->quarantine_size = (ASAN_LOW_MEMORY) ? 1UL << 26 : 1UL << 28;
f->redzone = 16;
f->max_redzone = 2048;
f->debug = false;
f->report_globals = 1;
f->check_initialization_order = false;
f->replace_str = true;
f->replace_intrin = true;
f->mac_ignore_invalid_free = false;
f->detect_stack_use_after_return = false; // Also needs the compiler flag.
f->min_uar_stack_size_log = 16; // We can't do smaller anyway.
f->max_uar_stack_size_log = 20; // 1Mb per size class, i.e. ~11Mb per thread.
f->uar_noreserve = false;
f->max_malloc_fill_size = 0x1000; // By default, fill only the first 4K.
f->malloc_fill_byte = 0xbe;
f->exitcode = ASAN_DEFAULT_FAILURE_EXITCODE;
f->allow_user_poisoning = true;
f->sleep_before_dying = 0;
f->check_malloc_usable_size = true;
f->unmap_shadow_on_exit = false;
f->abort_on_error = false;
f->print_stats = false;
f->print_legend = true;
f->atexit = false;
f->disable_core = (SANITIZER_WORDSIZE == 64);
f->allow_reexec = true;
f->print_full_thread_history = true;
f->poison_heap = true;
f->poison_partial = true;
// Turn off alloc/dealloc mismatch checker on Mac and Windows for now.
// https://code.google.com/p/address-sanitizer/issues/detail?id=131
// https://code.google.com/p/address-sanitizer/issues/detail?id=309
// TODO(glider,timurrrr): Fix known issues and enable this back.
f->alloc_dealloc_mismatch = (SANITIZER_MAC == 0) && (SANITIZER_WINDOWS == 0);
f->strict_memcmp = true;
f->strict_init_order = false;
f->start_deactivated = false;
f->detect_invalid_pointer_pairs = 0;
f->detect_container_overflow = true;
// Override from compile definition.
ParseFlagsFromString(f, MaybeUseAsanDefaultOptionsCompileDefinition());
// Override from user-specified string.
ParseFlagsFromString(f, MaybeCallAsanDefaultOptions());
VReport(1, "Using the defaults from __asan_default_options: %s\n",
MaybeCallAsanDefaultOptions());
// Override from command line.
ParseFlagsFromString(f, env);
if (common_flags()->help) {
PrintFlagDescriptions();
}
if (!CAN_SANITIZE_LEAKS && cf->detect_leaks) {
Report("%s: detect_leaks is not supported on this platform.\n",
SanitizerToolName);
cf->detect_leaks = false;
}
// Make "strict_init_order" imply "check_initialization_order".
// TODO(samsonov): Use a single runtime flag for an init-order checker.
if (f->strict_init_order) {
f->check_initialization_order = true;
}
}
// Parse flags that may change between startup and activation.
// On Android they come from a system property.
// On other platforms this is no-op.
void ParseExtraActivationFlags() {
char buf[100];
GetExtraActivationFlags(buf, sizeof(buf));
ParseFlagsFromString(flags(), buf);
if (buf[0] != '\0')
VReport(1, "Extra activation flags: %s\n", buf);
}
// -------------------------- Globals --------------------- {{{1
int asan_inited;
bool asan_init_is_running;
void (*death_callback)(void);
#if !ASAN_FIXED_MAPPING
uptr kHighMemEnd, kMidMemBeg, kMidMemEnd;
#endif
// -------------------------- Misc ---------------- {{{1
void ShowStatsAndAbort() {
__asan_print_accumulated_stats();
Die();
}
// ---------------------- mmap -------------------- {{{1
// Reserve memory range [beg, end].
static void ReserveShadowMemoryRange(uptr beg, uptr end) {
CHECK_EQ((beg % GetPageSizeCached()), 0);
CHECK_EQ(((end + 1) % GetPageSizeCached()), 0);
uptr size = end - beg + 1;
DecreaseTotalMmap(size); // Don't count the shadow against mmap_limit_mb.
void *res = MmapFixedNoReserve(beg, size);
if (res != (void*)beg) {
Report("ReserveShadowMemoryRange failed while trying to map 0x%zx bytes. "
"Perhaps you're using ulimit -v\n", size);
Abort();
}
}
// --------------- 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); \
void __asan_report_ ## type ## size(uptr addr) { \
GET_CALLER_PC_BP_SP; \
__asan_report_error(pc, bp, sp, addr, is_write, size); \
}
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); \
void __asan_report_ ## type ## _n(uptr addr, uptr size) { \
GET_CALLER_PC_BP_SP; \
__asan_report_error(pc, bp, sp, addr, is_write, size); \
}
ASAN_REPORT_ERROR_N(load, false)
ASAN_REPORT_ERROR_N(store, true)
#define ASAN_MEMORY_ACCESS_CALLBACK(type, is_write, size) \
extern "C" NOINLINE INTERFACE_ATTRIBUTE void __asan_##type##size(uptr addr); \
void __asan_##type##size(uptr addr) { \
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; \
__asan_report_error(pc, bp, sp, addr, is_write, size); \
} \
} \
} \
}
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;
__asan_report_error(pc, bp, sp, addr, false, size);
}
}
extern "C"
NOINLINE INTERFACE_ATTRIBUTE void __asan_storeN(uptr addr, uptr size) {
if (__asan_region_is_poisoned(addr, size)) {
GET_CALLER_PC_BP_SP;
__asan_report_error(pc, bp, sp, addr, true, size);
}
}
// 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.
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_store1(0); break;
case 7: __asan_report_store2(0); break;
case 8: __asan_report_store4(0); break;
case 9: __asan_report_store8(0); break;
case 10: __asan_report_store16(0); break;
case 12: __asan_register_globals(0, 0); break;
case 13: __asan_unregister_globals(0, 0); break;
case 14: __asan_set_death_callback(0); break;
case 15: __asan_set_error_report_callback(0); break;
case 16: __asan_handle_no_return(); break;
case 17: __asan_address_is_poisoned(0); break;
case 18: __asan_get_allocated_size(0); break;
case 19: __asan_get_current_allocated_bytes(); break;
case 20: __asan_get_estimated_allocated_size(0); break;
case 21: __asan_get_free_bytes(); break;
case 22: __asan_get_heap_size(); break;
case 23: __asan_get_ownership(0); break;
case 24: __asan_get_unmapped_bytes(); break;
case 25: __asan_poison_memory_region(0, 0); break;
case 26: __asan_unpoison_memory_region(0, 0); break;
case 27: __asan_set_error_exit_code(0); break;
case 30: __asan_before_dynamic_init(0); break;
case 31: __asan_after_dynamic_init(); break;
case 32: __asan_poison_stack_memory(0, 0); break;
case 33: __asan_unpoison_stack_memory(0, 0); break;
case 34: __asan_region_is_poisoned(0, 0); break;
case 35: __asan_describe_address(0); break;
}
}
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 !ASAN_FIXED_MAPPING
kHighMemEnd = GetMaxVirtualAddress();
// Increase kHighMemEnd to make sure it's properly
// aligned together with kHighMemBeg:
kHighMemEnd |= SHADOW_GRANULARITY * GetPageSizeCached() - 1;
#endif // !ASAN_FIXED_MAPPING
CHECK_EQ((kHighMemBeg % GetPageSizeCached()), 0);
}
static void ProtectGap(uptr a, uptr size) {
CHECK_EQ(a, (uptr)Mprotect(a, size));
}
static void PrintAddressSpaceLayout() {
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 %p %p",
(void*)MEM_TO_SHADOW(kLowShadowBeg),
(void*)MEM_TO_SHADOW(kLowShadowEnd),
(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=%zuM\n", (uptr)flags()->quarantine_size >> 20);
Printf("malloc_context_size=%zu\n",
(uptr)common_flags()->malloc_context_size);
Printf("SHADOW_SCALE: %zx\n", (uptr)SHADOW_SCALE);
Printf("SHADOW_GRANULARITY: %zx\n", (uptr)SHADOW_GRANULARITY);
Printf("SHADOW_OFFSET: %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;
// Initialize flags. This must be done early, because most of the
// initialization steps look at flags().
const char *options = GetEnv("ASAN_OPTIONS");
InitializeFlags(flags(), options);
InitializeHighMemEnd();
// Make sure we are not statically linked.
AsanDoesNotSupportStaticLinkage();
// Install tool-specific callbacks in sanitizer_common.
SetDieCallback(AsanDie);
SetCheckFailedCallback(AsanCheckFailed);
SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
if (!flags()->start_deactivated)
ParseExtraActivationFlags();
__sanitizer_set_report_path(common_flags()->log_path);
__asan_option_detect_stack_use_after_return =
flags()->detect_stack_use_after_return;
CHECK_LE(flags()->min_uar_stack_size_log, flags()->max_uar_stack_size_log);
if (options) {
VReport(1, "Parsed ASAN_OPTIONS: %s\n", options);
}
if (flags()->start_deactivated)
AsanStartDeactivated();
// Re-exec ourselves if we need to set additional env or command line args.
MaybeReexec();
// Setup internal allocator callback.
SetLowLevelAllocateCallback(OnLowLevelAllocate);
InitializeAsanInterceptors();
ReplaceSystemMalloc();
uptr shadow_start = kLowShadowBeg;
if (kLowShadowBeg)
shadow_start -= GetMmapGranularity();
bool full_shadow_is_available =
MemoryRangeIsAvailable(shadow_start, kHighShadowEnd);
#if SANITIZER_LINUX && defined(__x86_64__) && !ASAN_FIXED_MAPPING
if (!full_shadow_is_available) {
kMidMemBeg = kLowMemEnd < 0x3000000000ULL ? 0x3000000000ULL : 0;
kMidMemEnd = kLowMemEnd < 0x3000000000ULL ? 0x4fffffffffULL : 0;
}
#endif
if (common_flags()->verbosity)
PrintAddressSpaceLayout();
if (flags()->disable_core) {
DisableCoreDumper();
}
if (full_shadow_is_available) {
// mmap the low shadow plus at least one page at the left.
if (kLowShadowBeg)
ReserveShadowMemoryRange(shadow_start, kLowShadowEnd);
// mmap the high shadow.
ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd);
// protect the gap.
ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
CHECK_EQ(kShadowGapEnd, kHighShadowBeg - 1);
} else if (kMidMemBeg &&
MemoryRangeIsAvailable(shadow_start, kMidMemBeg - 1) &&
MemoryRangeIsAvailable(kMidMemEnd + 1, kHighShadowEnd)) {
CHECK(kLowShadowBeg != kLowShadowEnd);
// mmap the low shadow plus at least one page at the left.
ReserveShadowMemoryRange(shadow_start, kLowShadowEnd);
// mmap the mid shadow.
ReserveShadowMemoryRange(kMidShadowBeg, kMidShadowEnd);
// mmap the high shadow.
ReserveShadowMemoryRange(kHighShadowBeg, kHighShadowEnd);
// protect the gaps.
ProtectGap(kShadowGapBeg, kShadowGapEnd - kShadowGapBeg + 1);
ProtectGap(kShadowGap2Beg, kShadowGap2End - kShadowGap2Beg + 1);
ProtectGap(kShadowGap3Beg, kShadowGap3End - kShadowGap3Beg + 1);
} else {
Report("Shadow memory range interleaves with an existing memory mapping. "
"ASan cannot proceed correctly. ABORTING.\n");
DumpProcessMap();
Die();
}
AsanTSDInit(PlatformTSDDtor);
InstallDeadlySignalHandlers(AsanOnSIGSEGV);
// Allocator should be initialized before starting external symbolizer, as
// fork() on Mac locks the allocator.
InitializeAllocator();
Symbolizer::Init(common_flags()->external_symbolizer_path);
// 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);
if (common_flags()->coverage) {
__sanitizer_cov_init();
Atexit(__sanitizer_cov_dump);
}
// interceptors
InitTlsSize();
// Create main thread.
AsanThread *main_thread = AsanThread::Create(0, 0);
CreateThreadContextArgs create_main_args = { main_thread, 0 };
u32 main_tid = asanThreadRegistry().CreateThread(
0, true, 0, &create_main_args);
CHECK_EQ(0, main_tid);
SetCurrentThread(main_thread);
main_thread->ThreadStart(internal_getpid());
force_interface_symbols(); // no-op.
SanitizerInitializeUnwinder();
#if CAN_SANITIZE_LEAKS
__lsan::InitCommonLsan();
if (common_flags()->detect_leaks && common_flags()->leak_check_at_exit) {
Atexit(__lsan::DoLeakCheck);
}
#endif // CAN_SANITIZE_LEAKS
VReport(1, "AddressSanitizer Init done\n");
}
// 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 initializer from .preinit_array haven't run).
class AsanInitializer {
public: // NOLINT
AsanInitializer() {
AsanCheckIncompatibleRT();
AsanCheckDynamicRTPrereqs();
if (UNLIKELY(!asan_inited))
__asan_init();
}
};
static AsanInitializer asan_initializer;
#endif // ASAN_DYNAMIC
} // namespace __asan
// ---------------------- Interface ---------------- {{{1
using namespace __asan; // NOLINT
#if !SANITIZER_SUPPORTS_WEAK_HOOKS
extern "C" {
SANITIZER_INTERFACE_ATTRIBUTE SANITIZER_WEAK_ATTRIBUTE
const char* __asan_default_options() { return ""; }
} // extern "C"
#endif
int NOINLINE __asan_set_error_exit_code(int exit_code) {
int old = flags()->exitcode;
flags()->exitcode = exit_code;
return old;
}
void NOINLINE __asan_handle_no_return() {
int local_stack;
AsanThread *curr_thread = GetCurrentThread();
CHECK(curr_thread);
uptr PageSize = GetPageSizeCached();
uptr top = curr_thread->stack_top();
uptr bottom = ((uptr)&local_stack - PageSize) & ~(PageSize-1);
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 "
"http://code.google.com/p/address-sanitizer/issues/detail?id=189\n",
top, bottom, top - bottom, top - bottom);
return;
}
PoisonShadow(bottom, top - bottom, 0);
if (curr_thread->has_fake_stack())
curr_thread->fake_stack()->HandleNoReturn();
}
void NOINLINE __asan_set_death_callback(void (*callback)(void)) {
death_callback = 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() {
AsanCheckIncompatibleRT();
AsanActivate();
AsanInitInternal();
}