//===-- asan_errors.cc ------------------------------------------*- C++ -*-===//
//
// 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.
//
// ASan implementation for error structures.
//===----------------------------------------------------------------------===//
#include "asan_errors.h"
#include "asan_descriptions.h"
#include "asan_mapping.h"
#include "asan_report.h"
#include "asan_stack.h"
#include "sanitizer_common/sanitizer_stackdepot.h"
namespace __asan {
static void OnStackUnwind(const SignalContext &sig,
const void *callback_context,
BufferedStackTrace *stack) {
bool fast = common_flags()->fast_unwind_on_fatal;
#if SANITIZER_FREEBSD || SANITIZER_NETBSD
// On FreeBSD the slow unwinding that leverages _Unwind_Backtrace()
// yields the call stack of the signal's handler and not of the code
// that raised the signal (as it does on Linux).
fast = true;
#endif
// Tests and maybe some users expect that scariness is going to be printed
// just before the stack. As only asan has scariness score we have no
// corresponding code in the sanitizer_common and we use this callback to
// print it.
static_cast<const ScarinessScoreBase *>(callback_context)->Print();
GetStackTrace(stack, kStackTraceMax, sig.pc, sig.bp, sig.context, fast);
}
void ErrorDeadlySignal::Print() {
ReportDeadlySignal(signal, tid, &OnStackUnwind, &scariness);
}
void ErrorDoubleFree::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: attempting %s on %p in thread %s:\n",
scariness.GetDescription(), addr_description.addr,
AsanThreadIdAndName(tid).c_str());
Printf("%s", d.Default());
scariness.Print();
GET_STACK_TRACE_FATAL(second_free_stack->trace[0],
second_free_stack->top_frame_bp);
stack.Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), &stack);
}
void ErrorNewDeleteTypeMismatch::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: %s on %p in thread %s:\n",
scariness.GetDescription(), addr_description.addr,
AsanThreadIdAndName(tid).c_str());
Printf("%s object passed to delete has wrong type:\n", d.Default());
if (delete_size != 0) {
Printf(
" size of the allocated type: %zd bytes;\n"
" size of the deallocated type: %zd bytes.\n",
addr_description.chunk_access.chunk_size, delete_size);
}
const uptr user_alignment =
addr_description.chunk_access.user_requested_alignment;
if (delete_alignment != user_alignment) {
char user_alignment_str[32];
char delete_alignment_str[32];
internal_snprintf(user_alignment_str, sizeof(user_alignment_str),
"%zd bytes", user_alignment);
internal_snprintf(delete_alignment_str, sizeof(delete_alignment_str),
"%zd bytes", delete_alignment);
static const char *kDefaultAlignment = "default-aligned";
Printf(
" alignment of the allocated type: %s;\n"
" alignment of the deallocated type: %s.\n",
user_alignment > 0 ? user_alignment_str : kDefaultAlignment,
delete_alignment > 0 ? delete_alignment_str : kDefaultAlignment);
}
CHECK_GT(free_stack->size, 0);
scariness.Print();
GET_STACK_TRACE_FATAL(free_stack->trace[0], free_stack->top_frame_bp);
stack.Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), &stack);
Report(
"HINT: if you don't care about these errors you may set "
"ASAN_OPTIONS=new_delete_type_mismatch=0\n");
}
void ErrorFreeNotMalloced::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: attempting free on address "
"which was not malloc()-ed: %p in thread %s\n",
addr_description.Address(), AsanThreadIdAndName(tid).c_str());
Printf("%s", d.Default());
CHECK_GT(free_stack->size, 0);
scariness.Print();
GET_STACK_TRACE_FATAL(free_stack->trace[0], free_stack->top_frame_bp);
stack.Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), &stack);
}
void ErrorAllocTypeMismatch::Print() {
static const char *alloc_names[] = {"INVALID", "malloc", "operator new",
"operator new []"};
static const char *dealloc_names[] = {"INVALID", "free", "operator delete",
"operator delete []"};
CHECK_NE(alloc_type, dealloc_type);
Decorator d;
Printf("%s", d.Error());
Report("ERROR: AddressSanitizer: %s (%s vs %s) on %p\n",
scariness.GetDescription(), alloc_names[alloc_type],
dealloc_names[dealloc_type], addr_description.Address());
Printf("%s", d.Default());
CHECK_GT(dealloc_stack->size, 0);
scariness.Print();
GET_STACK_TRACE_FATAL(dealloc_stack->trace[0], dealloc_stack->top_frame_bp);
stack.Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), &stack);
Report(
"HINT: if you don't care about these errors you may set "
"ASAN_OPTIONS=alloc_dealloc_mismatch=0\n");
}
void ErrorMallocUsableSizeNotOwned::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: attempting to call malloc_usable_size() for "
"pointer which is not owned: %p\n",
addr_description.Address());
Printf("%s", d.Default());
stack->Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorSanitizerGetAllocatedSizeNotOwned::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: attempting to call "
"__sanitizer_get_allocated_size() for pointer which is not owned: %p\n",
addr_description.Address());
Printf("%s", d.Default());
stack->Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorCallocOverflow::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: calloc parameters overflow: count * size "
"(%zd * %zd) cannot be represented in type size_t (thread %s)\n",
count, size, AsanThreadIdAndName(tid).c_str());
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorPvallocOverflow::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: pvalloc parameters overflow: size 0x%zx "
"rounded up to system page size 0x%zx cannot be represented in type "
"size_t (thread %s)\n",
size, GetPageSizeCached(), AsanThreadIdAndName(tid).c_str());
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorInvalidAllocationAlignment::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: invalid allocation alignment: %zd, "
"alignment must be a power of two (thread %s)\n",
alignment, AsanThreadIdAndName(tid).c_str());
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorInvalidAlignedAllocAlignment::Print() {
Decorator d;
Printf("%s", d.Error());
#if SANITIZER_POSIX
Report("ERROR: AddressSanitizer: invalid alignment requested in "
"aligned_alloc: %zd, alignment must be a power of two and the "
"requested size 0x%zx must be a multiple of alignment "
"(thread %s)\n", alignment, size, AsanThreadIdAndName(tid).c_str());
#else
Report("ERROR: AddressSanitizer: invalid alignment requested in "
"aligned_alloc: %zd, the requested size 0x%zx must be a multiple of "
"alignment (thread %s)\n", alignment, size,
AsanThreadIdAndName(tid).c_str());
#endif
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorInvalidPosixMemalignAlignment::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: invalid alignment requested in posix_memalign: "
"%zd, alignment must be a power of two and a multiple of sizeof(void*) "
"== %zd (thread %s)\n",
alignment, sizeof(void*), AsanThreadIdAndName(tid).c_str()); // NOLINT
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorAllocationSizeTooBig::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: requested allocation size 0x%zx (0x%zx after "
"adjustments for alignment, red zones etc.) exceeds maximum supported "
"size of 0x%zx (thread %s)\n",
user_size, total_size, max_size, AsanThreadIdAndName(tid).c_str());
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorRssLimitExceeded::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: specified RSS limit exceeded, currently set to "
"soft_rss_limit_mb=%zd\n", common_flags()->soft_rss_limit_mb);
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorOutOfMemory::Print() {
Decorator d;
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: allocator is out of memory trying to allocate "
"0x%zx bytes\n", requested_size);
Printf("%s", d.Default());
stack->Print();
PrintHintAllocatorCannotReturnNull();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorStringFunctionMemoryRangesOverlap::Print() {
Decorator d;
char bug_type[100];
internal_snprintf(bug_type, sizeof(bug_type), "%s-param-overlap", function);
Printf("%s", d.Error());
Report(
"ERROR: AddressSanitizer: %s: memory ranges [%p,%p) and [%p, %p) "
"overlap\n",
bug_type, addr1_description.Address(),
addr1_description.Address() + length1, addr2_description.Address(),
addr2_description.Address() + length2);
Printf("%s", d.Default());
scariness.Print();
stack->Print();
addr1_description.Print();
addr2_description.Print();
ReportErrorSummary(bug_type, stack);
}
void ErrorStringFunctionSizeOverflow::Print() {
Decorator d;
Printf("%s", d.Error());
Report("ERROR: AddressSanitizer: %s: (size=%zd)\n",
scariness.GetDescription(), size);
Printf("%s", d.Default());
scariness.Print();
stack->Print();
addr_description.Print();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorBadParamsToAnnotateContiguousContainer::Print() {
Report(
"ERROR: AddressSanitizer: bad parameters to "
"__sanitizer_annotate_contiguous_container:\n"
" beg : %p\n"
" end : %p\n"
" old_mid : %p\n"
" new_mid : %p\n",
beg, end, old_mid, new_mid);
uptr granularity = SHADOW_GRANULARITY;
if (!IsAligned(beg, granularity))
Report("ERROR: beg is not aligned by %d\n", granularity);
stack->Print();
ReportErrorSummary(scariness.GetDescription(), stack);
}
void ErrorODRViolation::Print() {
Decorator d;
Printf("%s", d.Error());
Report("ERROR: AddressSanitizer: %s (%p):\n", scariness.GetDescription(),
global1.beg);
Printf("%s", d.Default());
InternalScopedString g1_loc(256), g2_loc(256);
PrintGlobalLocation(&g1_loc, global1);
PrintGlobalLocation(&g2_loc, global2);
Printf(" [1] size=%zd '%s' %s\n", global1.size,
MaybeDemangleGlobalName(global1.name), g1_loc.data());
Printf(" [2] size=%zd '%s' %s\n", global2.size,
MaybeDemangleGlobalName(global2.name), g2_loc.data());
if (stack_id1 && stack_id2) {
Printf("These globals were registered at these points:\n");
Printf(" [1]:\n");
StackDepotGet(stack_id1).Print();
Printf(" [2]:\n");
StackDepotGet(stack_id2).Print();
}
Report(
"HINT: if you don't care about these errors you may set "
"ASAN_OPTIONS=detect_odr_violation=0\n");
InternalScopedString error_msg(256);
error_msg.append("%s: global '%s' at %s", scariness.GetDescription(),
MaybeDemangleGlobalName(global1.name), g1_loc.data());
ReportErrorSummary(error_msg.data());
}
void ErrorInvalidPointerPair::Print() {
Decorator d;
Printf("%s", d.Error());
Report("ERROR: AddressSanitizer: %s: %p %p\n", scariness.GetDescription(),
addr1_description.Address(), addr2_description.Address());
Printf("%s", d.Default());
GET_STACK_TRACE_FATAL(pc, bp);
stack.Print();
addr1_description.Print();
addr2_description.Print();
ReportErrorSummary(scariness.GetDescription(), &stack);
}
static bool AdjacentShadowValuesAreFullyPoisoned(u8 *s) {
return s[-1] > 127 && s[1] > 127;
}
ErrorGeneric::ErrorGeneric(u32 tid, uptr pc_, uptr bp_, uptr sp_, uptr addr,
bool is_write_, uptr access_size_)
: ErrorBase(tid),
addr_description(addr, access_size_, /*shouldLockThreadRegistry=*/false),
pc(pc_),
bp(bp_),
sp(sp_),
access_size(access_size_),
is_write(is_write_),
shadow_val(0) {
scariness.Clear();
if (access_size) {
if (access_size <= 9) {
char desr[] = "?-byte";
desr[0] = '0' + access_size;
scariness.Scare(access_size + access_size / 2, desr);
} else if (access_size >= 10) {
scariness.Scare(15, "multi-byte");
}
is_write ? scariness.Scare(20, "write") : scariness.Scare(1, "read");
// Determine the error type.
bug_descr = "unknown-crash";
if (AddrIsInMem(addr)) {
u8 *shadow_addr = (u8 *)MemToShadow(addr);
// If we are accessing 16 bytes, look at the second shadow byte.
if (*shadow_addr == 0 && access_size > SHADOW_GRANULARITY) shadow_addr++;
// If we are in the partial right redzone, look at the next shadow byte.
if (*shadow_addr > 0 && *shadow_addr < 128) shadow_addr++;
bool far_from_bounds = false;
shadow_val = *shadow_addr;
int bug_type_score = 0;
// For use-after-frees reads are almost as bad as writes.
int read_after_free_bonus = 0;
switch (shadow_val) {
case kAsanHeapLeftRedzoneMagic:
case kAsanArrayCookieMagic:
bug_descr = "heap-buffer-overflow";
bug_type_score = 10;
far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
break;
case kAsanHeapFreeMagic:
bug_descr = "heap-use-after-free";
bug_type_score = 20;
if (!is_write) read_after_free_bonus = 18;
break;
case kAsanStackLeftRedzoneMagic:
bug_descr = "stack-buffer-underflow";
bug_type_score = 25;
far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
break;
case kAsanInitializationOrderMagic:
bug_descr = "initialization-order-fiasco";
bug_type_score = 1;
break;
case kAsanStackMidRedzoneMagic:
case kAsanStackRightRedzoneMagic:
bug_descr = "stack-buffer-overflow";
bug_type_score = 25;
far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
break;
case kAsanStackAfterReturnMagic:
bug_descr = "stack-use-after-return";
bug_type_score = 30;
if (!is_write) read_after_free_bonus = 18;
break;
case kAsanUserPoisonedMemoryMagic:
bug_descr = "use-after-poison";
bug_type_score = 20;
break;
case kAsanContiguousContainerOOBMagic:
bug_descr = "container-overflow";
bug_type_score = 10;
break;
case kAsanStackUseAfterScopeMagic:
bug_descr = "stack-use-after-scope";
bug_type_score = 10;
break;
case kAsanGlobalRedzoneMagic:
bug_descr = "global-buffer-overflow";
bug_type_score = 10;
far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
break;
case kAsanIntraObjectRedzone:
bug_descr = "intra-object-overflow";
bug_type_score = 10;
break;
case kAsanAllocaLeftMagic:
case kAsanAllocaRightMagic:
bug_descr = "dynamic-stack-buffer-overflow";
bug_type_score = 25;
far_from_bounds = AdjacentShadowValuesAreFullyPoisoned(shadow_addr);
break;
}
scariness.Scare(bug_type_score + read_after_free_bonus, bug_descr);
if (far_from_bounds) scariness.Scare(10, "far-from-bounds");
}
}
}
static void PrintContainerOverflowHint() {
Printf("HINT: if you don't care about these errors you may set "
"ASAN_OPTIONS=detect_container_overflow=0.\n"
"If you suspect a false positive see also: "
"https://github.com/google/sanitizers/wiki/"
"AddressSanitizerContainerOverflow.\n");
}
static void PrintShadowByte(InternalScopedString *str, const char *before,
u8 byte, const char *after = "\n") {
PrintMemoryByte(str, before, byte, /*in_shadow*/true, after);
}
static void PrintLegend(InternalScopedString *str) {
str->append(
"Shadow byte legend (one shadow byte represents %d "
"application bytes):\n",
(int)SHADOW_GRANULARITY);
PrintShadowByte(str, " Addressable: ", 0);
str->append(" Partially addressable: ");
for (u8 i = 1; i < SHADOW_GRANULARITY; i++) PrintShadowByte(str, "", i, " ");
str->append("\n");
PrintShadowByte(str, " Heap left redzone: ",
kAsanHeapLeftRedzoneMagic);
PrintShadowByte(str, " Freed heap region: ", kAsanHeapFreeMagic);
PrintShadowByte(str, " Stack left redzone: ",
kAsanStackLeftRedzoneMagic);
PrintShadowByte(str, " Stack mid redzone: ",
kAsanStackMidRedzoneMagic);
PrintShadowByte(str, " Stack right redzone: ",
kAsanStackRightRedzoneMagic);
PrintShadowByte(str, " Stack after return: ",
kAsanStackAfterReturnMagic);
PrintShadowByte(str, " Stack use after scope: ",
kAsanStackUseAfterScopeMagic);
PrintShadowByte(str, " Global redzone: ", kAsanGlobalRedzoneMagic);
PrintShadowByte(str, " Global init order: ",
kAsanInitializationOrderMagic);
PrintShadowByte(str, " Poisoned by user: ",
kAsanUserPoisonedMemoryMagic);
PrintShadowByte(str, " Container overflow: ",
kAsanContiguousContainerOOBMagic);
PrintShadowByte(str, " Array cookie: ",
kAsanArrayCookieMagic);
PrintShadowByte(str, " Intra object redzone: ",
kAsanIntraObjectRedzone);
PrintShadowByte(str, " ASan internal: ", kAsanInternalHeapMagic);
PrintShadowByte(str, " Left alloca redzone: ", kAsanAllocaLeftMagic);
PrintShadowByte(str, " Right alloca redzone: ", kAsanAllocaRightMagic);
PrintShadowByte(str, " Shadow gap: ", kAsanShadowGap);
}
static void PrintShadowBytes(InternalScopedString *str, const char *before,
u8 *bytes, u8 *guilty, uptr n) {
Decorator d;
if (before) str->append("%s%p:", before, bytes);
for (uptr i = 0; i < n; i++) {
u8 *p = bytes + i;
const char *before =
p == guilty ? "[" : (p - 1 == guilty && i != 0) ? "" : " ";
const char *after = p == guilty ? "]" : "";
PrintShadowByte(str, before, *p, after);
}
str->append("\n");
}
static void PrintShadowMemoryForAddress(uptr addr) {
if (!AddrIsInMem(addr)) return;
uptr shadow_addr = MemToShadow(addr);
const uptr n_bytes_per_row = 16;
uptr aligned_shadow = shadow_addr & ~(n_bytes_per_row - 1);
InternalScopedString str(4096 * 8);
str.append("Shadow bytes around the buggy address:\n");
for (int i = -5; i <= 5; i++) {
uptr row_shadow_addr = aligned_shadow + i * n_bytes_per_row;
// Skip rows that would be outside the shadow range. This can happen when
// the user address is near the bottom, top, or shadow gap of the address
// space.
if (!AddrIsInShadow(row_shadow_addr)) continue;
const char *prefix = (i == 0) ? "=>" : " ";
PrintShadowBytes(&str, prefix, (u8 *)row_shadow_addr, (u8 *)shadow_addr,
n_bytes_per_row);
}
if (flags()->print_legend) PrintLegend(&str);
Printf("%s", str.data());
}
void ErrorGeneric::Print() {
Decorator d;
Printf("%s", d.Error());
uptr addr = addr_description.Address();
Report("ERROR: AddressSanitizer: %s on address %p at pc %p bp %p sp %p\n",
bug_descr, (void *)addr, pc, bp, sp);
Printf("%s", d.Default());
Printf("%s%s of size %zu at %p thread %s%s\n", d.Access(),
access_size ? (is_write ? "WRITE" : "READ") : "ACCESS", access_size,
(void *)addr, AsanThreadIdAndName(tid).c_str(), d.Default());
scariness.Print();
GET_STACK_TRACE_FATAL(pc, bp);
stack.Print();
// Pass bug_descr because we have a special case for
// initialization-order-fiasco
addr_description.Print(bug_descr);
if (shadow_val == kAsanContiguousContainerOOBMagic)
PrintContainerOverflowHint();
ReportErrorSummary(bug_descr, &stack);
PrintShadowMemoryForAddress(addr);
}
} // namespace __asan