ladybird/AK/UBSanitizer.h
Andrew Kaster db33cdbc2f AK+LibSanitizer: Add method to zero out a UBSAN SourceLocation
This is the same strategy that LLVM's compiler-rt uses to make sure that
each UBSAN error is only reported once, when UBSAN is *not* deadly.

Otherwise, each time we head through a UB codepath, we will log the same
error over and over. That behavior just adds noise to the logs and makes
it nearly impossible to run binaires that have some common code path
with flagged UB in them.

compiler-rt goes the extra step to make sure the "clear" action is
atomic, but we don't really have that many multi-threaded apps gettting
tested with UBSAN yet, so we can add that later.
2021-12-15 10:30:32 -08:00

157 lines
3.5 KiB
C++

/*
* Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include "AK/Noncopyable.h"
#include "AK/StdLibExtras.h"
#include <AK/Types.h>
namespace AK::UBSanitizer {
extern bool g_ubsan_is_deadly;
typedef void* ValueHandle;
class SourceLocation {
AK_MAKE_NONCOPYABLE(SourceLocation);
public:
const char* filename() const { return m_filename; }
u32 line() const { return m_line; }
u32 column() const { return m_column; }
// Replace the location information in the .data segment with one that won't be logged in the future
// Using this method prevents log spam when sanitizers are not deadly by not logging the exact same
// code paths multiple times.
SourceLocation permanently_clear() { return move(*this); }
bool needs_logging() const { return !(m_filename == nullptr); }
SourceLocation() = default;
SourceLocation(SourceLocation&& other)
: m_filename(other.m_filename)
, m_line(other.m_line)
, m_column(other.m_column)
{
other = {};
}
SourceLocation& operator=(SourceLocation&& other)
{
if (this != &other) {
m_filename = exchange(other.m_filename, nullptr);
m_line = exchange(other.m_line, 0);
m_column = exchange(other.m_column, 0);
}
return *this;
}
private:
const char* m_filename { nullptr };
u32 m_line { 0 };
u32 m_column { 0 };
};
enum TypeKind : u16 {
Integer = 0,
Float = 1,
Unknown = 0xffff,
};
class TypeDescriptor {
public:
const char* name() const { return m_name; }
TypeKind kind() const { return (TypeKind)m_kind; }
bool is_integer() const { return kind() == TypeKind::Integer; }
bool is_signed() const { return m_info & 1; }
bool is_unsigned() const { return !is_signed(); }
size_t bit_width() const { return 1 << (m_info >> 1); }
private:
u16 m_kind;
u16 m_info;
char m_name[1];
};
struct InvalidValueData {
SourceLocation location;
const TypeDescriptor& type;
};
struct NonnullArgData {
SourceLocation location;
SourceLocation attribute_location;
int argument_index;
};
struct NonnullReturnData {
SourceLocation attribute_location;
};
struct OverflowData {
SourceLocation location;
const TypeDescriptor& type;
};
struct VLABoundData {
SourceLocation location;
const TypeDescriptor& type;
};
struct ShiftOutOfBoundsData {
SourceLocation location;
const TypeDescriptor& lhs_type;
const TypeDescriptor& rhs_type;
};
struct OutOfBoundsData {
SourceLocation location;
const TypeDescriptor& array_type;
const TypeDescriptor& index_type;
};
struct TypeMismatchData {
SourceLocation location;
const TypeDescriptor& type;
u8 log_alignment;
u8 type_check_kind;
};
struct AlignmentAssumptionData {
SourceLocation location;
SourceLocation assumption_location;
const TypeDescriptor& type;
};
struct UnreachableData {
SourceLocation location;
};
struct ImplicitConversionData {
SourceLocation location;
const TypeDescriptor& from_type;
const TypeDescriptor& to_type;
/* ImplicitConversionCheckKind */ unsigned char kind;
};
struct InvalidBuiltinData {
SourceLocation location;
unsigned char kind;
};
struct PointerOverflowData {
SourceLocation location;
};
struct FloatCastOverflowData {
SourceLocation location;
TypeDescriptor const& from_type;
TypeDescriptor const& to_type;
};
}