kern_ubsan.c

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/*      $NetBSD: ubsan.c,v 1.3 2018/08/03 16:31:04 kamil Exp $  */
 
/*-
 * Copyright (c) 2018 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
 
/*
 * The micro UBSan implementation for the userland (uUBSan) and kernel (kUBSan).
 * The uBSSan versions is suitable for inclusion into libc or used standalone
 * with ATF tests.
 *
 * This file due to long symbol names generated by a compiler during the
 * instrumentation process does not follow the KNF style with 80-column limit.
 */
 
#include <sys/cdefs.h>
#ifdef __FreeBSD__
__FBSDID("$FreeBSD$");
#else
#if defined(_KERNEL)
__KERNEL_RCSID(0, "$NetBSD: ubsan.c,v 1.3 2018/08/03 16:31:04 kamil Exp $");
#else
__RCSID("$NetBSD: ubsan.c,v 1.3 2018/08/03 16:31:04 kamil Exp $");
#endif
#endif
 
#if defined(_KERNEL)
#include <sys/param.h>
#include <sys/types.h>
#include <sys/limits.h>
#include <sys/systm.h>
#include <machine/_inttypes.h>
#include <machine/stdarg.h>
#define ASSERT(x) KASSERT(x, ("%s: " __STRING(x) " failed", __func__))
#define __arraycount(x) nitems(x)
#define ISSET(x, y)     ((x) & (y))
#define __BIT(x)        ((uintmax_t)1 << (uintmax_t)(x))
#define __LOWEST_SET_BIT(__mask) ((((__mask) - 1) & (__mask)) ^ (__mask))
#define __SHIFTOUT(__x, __mask) (((__x) & (__mask)) / __LOWEST_SET_BIT(__mask))
#else
#if defined(_LIBC)
#include "namespace.h"
#endif
#include <sys/param.h>
#include <assert.h>
#include <inttypes.h>
#include <math.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#if defined(_LIBC)
#include "extern.h"
#define ubsan_vsyslog vsyslog_ss
#define ASSERT(x) _DIAGASSERT(x)
#else
#define ubsan_vsyslog vsyslog_r
#define ASSERT(x) assert(x)
#endif
/* These macros are available in _KERNEL only */
#define SET(t, f)       ((t) |= (f))
#define ISSET(t, f)     ((t) & (f))
#define CLR(t, f)       ((t) &= ~(f))
#endif
 
#define REINTERPRET_CAST(__dt, __st)    ((__dt)(__st))
#define STATIC_CAST(__dt, __st)         ((__dt)(__st))
 
#define ACK_REPORTED    __BIT(31)
 
#define MUL_STRING      "*"
#define PLUS_STRING     "+"
#define MINUS_STRING    "-"
#define DIVREM_STRING   "divrem"
 
#define CFI_VCALL               0
#define CFI_NVCALL              1
#define CFI_DERIVEDCAST         2
#define CFI_UNRELATEDCAST       3
#define CFI_ICALL               4
#define CFI_NVMFCALL            5
#define CFI_VMFCALL             6
 
#define NUMBER_MAXLEN   128
#define LOCATION_MAXLEN (PATH_MAX + 32 /* ':LINE:COLUMN' */)
 
#define WIDTH_8         8
#define WIDTH_16        16
#define WIDTH_32        32
#define WIDTH_64        64
#define WIDTH_80        80
#define WIDTH_96        96
#define WIDTH_128       128
 
#define NUMBER_SIGNED_BIT       1U
 
#if __SIZEOF_INT128__
typedef __int128 longest;
typedef unsigned __int128 ulongest;
#else
typedef int64_t longest;
typedef uint64_t ulongest;
#endif
 
#ifndef _KERNEL
static int ubsan_flags = -1;
#define UBSAN_ABORT     __BIT(0)
#define UBSAN_STDOUT    __BIT(1)
#define UBSAN_STDERR    __BIT(2)
#define UBSAN_SYSLOG    __BIT(3)
#endif
 
/* Undefined Behavior specific defines and structures */
 
#define KIND_INTEGER    0
#define KIND_FLOAT      1
#define KIND_UNKNOWN    UINT16_MAX
 
struct CSourceLocation {
        char *mFilename;
        uint32_t mLine;
        uint32_t mColumn;
};
 
struct CTypeDescriptor {
        uint16_t mTypeKind;
        uint16_t mTypeInfo;
        uint8_t mTypeName[1];
};
 
struct COverflowData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
};
 
struct CUnreachableData {
        struct CSourceLocation mLocation;
};
 
struct CCFICheckFailData {
        uint8_t mCheckKind;
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
};
 
struct CDynamicTypeCacheMissData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
        void *mTypeInfo;
        uint8_t mTypeCheckKind;
};
 
struct CFunctionTypeMismatchData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
};
 
struct CInvalidBuiltinData {
        struct CSourceLocation mLocation;
        uint8_t mKind;
};
 
struct CInvalidValueData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
};
 
struct CNonNullArgData {
        struct CSourceLocation mLocation;
        struct CSourceLocation mAttributeLocation;
        int mArgIndex;
};
 
struct CNonNullReturnData {
        struct CSourceLocation mAttributeLocation;
};
 
struct COutOfBoundsData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mArrayType;
        struct CTypeDescriptor *mIndexType;
};
 
struct CPointerOverflowData {
        struct CSourceLocation mLocation;
};
 
struct CShiftOutOfBoundsData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mLHSType;
        struct CTypeDescriptor *mRHSType;
};
 
struct CTypeMismatchData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
        unsigned long mLogAlignment;
        uint8_t mTypeCheckKind;
};
 
struct CTypeMismatchData_v1 {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
        uint8_t mLogAlignment;
        uint8_t mTypeCheckKind;
};
 
struct CVLABoundData {
        struct CSourceLocation mLocation;
        struct CTypeDescriptor *mType;
};
 
struct CFloatCastOverflowData {
        struct CSourceLocation mLocation;       /* This field exists in this struct since 2015 August 11th */
        struct CTypeDescriptor *mFromType;
        struct CTypeDescriptor *mToType;
};
 
struct CAlignmentAssumptionData {
        struct CSourceLocation mLocation;
        struct CSourceLocation mAssumptionLocation;
        struct CTypeDescriptor *mType;
};
 
/* Local utility functions */
static void Report(bool isFatal, const char *pFormat, ...) __printflike(2, 3);
static bool isAlreadyReported(struct CSourceLocation *pLocation);
static size_t zDeserializeTypeWidth(struct CTypeDescriptor *pType);
static void DeserializeLocation(char *pBuffer, size_t zBUfferLength, struct CSourceLocation *pLocation);
#ifdef __SIZEOF_INT128__
static void DeserializeUINT128(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, __uint128_t U128);
#endif
static void DeserializeNumberSigned(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, longest L);
static void DeserializeNumberUnsigned(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, ulongest L);
#ifndef _KERNEL
static void DeserializeFloatOverPointer(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long *pNumber);
static void DeserializeFloatInlined(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long ulNumber);
#endif
static longest llliGetNumber(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber);
static ulongest llluGetNumber(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber);
#ifndef _KERNEL
static void DeserializeNumberFloat(char *szLocation, char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long ulNumber);
#endif
static void DeserializeNumber(char *szLocation, char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long ulNumber);
static const char *DeserializeTypeCheckKind(uint8_t hhuTypeCheckKind);
static const char *DeserializeBuiltinCheckKind(uint8_t hhuBuiltinCheckKind);
static const char *DeserializeCFICheckKind(uint8_t hhuCFICheckKind);
static bool isNegativeNumber(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber);
static bool isShiftExponentTooLarge(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber, size_t zWidth);
 
/* Unused in this implementation, emitted by the C++ check dynamic type cast. */
intptr_t __ubsan_vptr_type_cache[128];
 
/* Public symbols used in the instrumentation of the code generation part */
void __ubsan_handle_add_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_add_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_alignment_assumption(struct CAlignmentAssumptionData *pData, unsigned long ulPointer, unsigned long ulAlignment, unsigned long ulOffset);
void __ubsan_handle_alignment_assumption_abort(struct CAlignmentAssumptionData *pData, unsigned long ulPointer, unsigned long ulAlignment, unsigned long ulOffset);
void __ubsan_handle_builtin_unreachable(struct CUnreachableData *pData);
void __ubsan_handle_cfi_bad_type(struct CCFICheckFailData *pData, unsigned long ulVtable, bool bValidVtable, bool FromUnrecoverableHandler, unsigned long ProgramCounter, unsigned long FramePointer);
void __ubsan_handle_cfi_check_fail(struct CCFICheckFailData *pData, unsigned long ulValue, unsigned long ulValidVtable);
void __ubsan_handle_cfi_check_fail_abort(struct CCFICheckFailData *pData, unsigned long ulValue, unsigned long ulValidVtable);
void __ubsan_handle_divrem_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_divrem_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_dynamic_type_cache_miss(struct CDynamicTypeCacheMissData *pData, unsigned long ulPointer, unsigned long ulHash);
void __ubsan_handle_dynamic_type_cache_miss_abort(struct CDynamicTypeCacheMissData *pData, unsigned long ulPointer, unsigned long ulHash);
void __ubsan_handle_float_cast_overflow(struct CFloatCastOverflowData *pData, unsigned long ulFrom);
void __ubsan_handle_float_cast_overflow_abort(struct CFloatCastOverflowData *pData, unsigned long ulFrom);
void __ubsan_handle_function_type_mismatch(struct CFunctionTypeMismatchData *pData, unsigned long ulFunction);
void __ubsan_handle_function_type_mismatch_abort(struct CFunctionTypeMismatchData *pData, unsigned long ulFunction);
void __ubsan_handle_invalid_builtin(struct CInvalidBuiltinData *pData);
void __ubsan_handle_invalid_builtin_abort(struct CInvalidBuiltinData *pData);
void __ubsan_handle_load_invalid_value(struct CInvalidValueData *pData, unsigned long ulVal);
void __ubsan_handle_load_invalid_value_abort(struct CInvalidValueData *pData, unsigned long ulVal);
void __ubsan_handle_missing_return(struct CUnreachableData *pData);
void __ubsan_handle_mul_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_mul_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_negate_overflow(struct COverflowData *pData, unsigned long ulOldVal);
void __ubsan_handle_negate_overflow_abort(struct COverflowData *pData, unsigned long ulOldVal);
void __ubsan_handle_nonnull_arg(struct CNonNullArgData *pData);
void __ubsan_handle_nonnull_arg_abort(struct CNonNullArgData *pData);
void __ubsan_handle_nonnull_return_v1(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer);
void __ubsan_handle_nonnull_return_v1_abort(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer);
void __ubsan_handle_nullability_arg(struct CNonNullArgData *pData);
void __ubsan_handle_nullability_arg_abort(struct CNonNullArgData *pData);
void __ubsan_handle_nullability_return_v1(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer);
void __ubsan_handle_nullability_return_v1_abort(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer);
void __ubsan_handle_out_of_bounds(struct COutOfBoundsData *pData, unsigned long ulIndex);
void __ubsan_handle_out_of_bounds_abort(struct COutOfBoundsData *pData, unsigned long ulIndex);
void __ubsan_handle_pointer_overflow(struct CPointerOverflowData *pData, unsigned long ulBase, unsigned long ulResult);
void __ubsan_handle_pointer_overflow_abort(struct CPointerOverflowData *pData, unsigned long ulBase, unsigned long ulResult);
void __ubsan_handle_shift_out_of_bounds(struct CShiftOutOfBoundsData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_shift_out_of_bounds_abort(struct CShiftOutOfBoundsData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_sub_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_sub_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS);
void __ubsan_handle_type_mismatch(struct CTypeMismatchData *pData, unsigned long ulPointer);
void __ubsan_handle_type_mismatch_abort(struct CTypeMismatchData *pData, unsigned long ulPointer);
void __ubsan_handle_type_mismatch_v1(struct CTypeMismatchData_v1 *pData, unsigned long ulPointer);
void __ubsan_handle_type_mismatch_v1_abort(struct CTypeMismatchData_v1 *pData, unsigned long ulPointer);
void __ubsan_handle_vla_bound_not_positive(struct CVLABoundData *pData, unsigned long ulBound);
void __ubsan_handle_vla_bound_not_positive_abort(struct CVLABoundData *pData, unsigned long ulBound);
void __ubsan_get_current_report_data(const char **ppOutIssueKind, const char **ppOutMessage, const char **ppOutFilename, uint32_t *pOutLine, uint32_t *pOutCol, char **ppOutMemoryAddr);
 
static void HandleOverflow(bool isFatal, struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS, const char *szOperation);
static void HandleNegateOverflow(bool isFatal, struct COverflowData *pData, unsigned long ulOldValue);
static void HandleBuiltinUnreachable(bool isFatal, struct CUnreachableData *pData);
static void HandleTypeMismatch(bool isFatal, struct CSourceLocation *mLocation, struct CTypeDescriptor *mType, unsigned long mLogAlignment, uint8_t mTypeCheckKind, unsigned long ulPointer);
static void HandleVlaBoundNotPositive(bool isFatal, struct CVLABoundData *pData, unsigned long ulBound);
static void HandleOutOfBounds(bool isFatal, struct COutOfBoundsData *pData, unsigned long ulIndex);
static void HandleShiftOutOfBounds(bool isFatal, struct CShiftOutOfBoundsData *pData, unsigned long ulLHS, unsigned long ulRHS);
static void HandleLoadInvalidValue(bool isFatal, struct CInvalidValueData *pData, unsigned long ulValue);
static void HandleInvalidBuiltin(bool isFatal, struct CInvalidBuiltinData *pData);
static void HandleFunctionTypeMismatch(bool isFatal, struct CFunctionTypeMismatchData *pData, unsigned long ulFunction);
static void HandleCFIBadType(bool isFatal, struct CCFICheckFailData *pData, unsigned long ulVtable, bool *bValidVtable, bool *FromUnrecoverableHandler, unsigned long *ProgramCounter, unsigned long *FramePointer);
static void HandleDynamicTypeCacheMiss(bool isFatal, struct CDynamicTypeCacheMissData *pData, unsigned long ulPointer, unsigned long ulHash);
static void HandleFloatCastOverflow(bool isFatal, struct CFloatCastOverflowData *pData, unsigned long ulFrom);
static void HandleMissingReturn(bool isFatal, struct CUnreachableData *pData);
static void HandleNonnullArg(bool isFatal, struct CNonNullArgData *pData);
static void HandleNonnullReturn(bool isFatal, struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer);
static void HandlePointerOverflow(bool isFatal, struct CPointerOverflowData *pData, unsigned long ulBase, unsigned long ulResult);
static void HandleAlignmentAssumption(bool isFatal, struct CAlignmentAssumptionData *pData, unsigned long ulPointer, unsigned long ulAlignment, unsigned long ulOffset);
 
static void
HandleOverflow(bool isFatal, struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS, const char *szOperation)
{
        char szLocation[LOCATION_MAXLEN];
        char szLHS[NUMBER_MAXLEN];
        char szRHS[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szLHS, NUMBER_MAXLEN, pData->mType, ulLHS);
        DeserializeNumber(szLocation, szRHS, NUMBER_MAXLEN, pData->mType, ulRHS);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, %s integer overflow: %s %s %s cannot be represented in type %s\n",
               szLocation, ISSET(pData->mType->mTypeInfo, NUMBER_SIGNED_BIT) ? "signed" : "unsigned", szLHS, szOperation, szRHS, pData->mType->mTypeName);
}
 
static void
HandleNegateOverflow(bool isFatal, struct COverflowData *pData, unsigned long ulOldValue)
{
        char szLocation[LOCATION_MAXLEN];
        char szOldValue[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szOldValue, NUMBER_MAXLEN, pData->mType, ulOldValue);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, negation of %s cannot be represented in type %s\n",
               szLocation, szOldValue, pData->mType->mTypeName);
}
 
static void
HandleBuiltinUnreachable(bool isFatal, struct CUnreachableData *pData)
{
        char szLocation[LOCATION_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, calling __builtin_unreachable()\n",
               szLocation);
}
 
static void
HandleTypeMismatch(bool isFatal, struct CSourceLocation *mLocation, struct CTypeDescriptor *mType, unsigned long mLogAlignment, uint8_t mTypeCheckKind, unsigned long ulPointer)
{
        char szLocation[LOCATION_MAXLEN];
 
        ASSERT(mLocation);
        ASSERT(mType);
 
        if (isAlreadyReported(mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, mLocation);
 
        if (ulPointer == 0) {
                Report(isFatal, "UBSan: Undefined Behavior in %s, %s null pointer of type %s\n",
                       szLocation, DeserializeTypeCheckKind(mTypeCheckKind), mType->mTypeName);
        } else if ((mLogAlignment - 1) & ulPointer) {
                Report(isFatal, "UBSan: Undefined Behavior in %s, %s misaligned address %p for type %s which requires %ld byte alignment\n",
                       szLocation, DeserializeTypeCheckKind(mTypeCheckKind), REINTERPRET_CAST(void *, ulPointer), mType->mTypeName, mLogAlignment);
        } else {
                Report(isFatal, "UBSan: Undefined Behavior in %s, %s address %p with insufficient space for an object of type %s\n",
                       szLocation, DeserializeTypeCheckKind(mTypeCheckKind), REINTERPRET_CAST(void *, ulPointer), mType->mTypeName);
        }
}
 
static void
HandleVlaBoundNotPositive(bool isFatal, struct CVLABoundData *pData, unsigned long ulBound)
{
        char szLocation[LOCATION_MAXLEN];
        char szBound[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szBound, NUMBER_MAXLEN, pData->mType, ulBound);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, variable length array bound value %s <= 0\n",
               szLocation, szBound);
}
 
static void
HandleOutOfBounds(bool isFatal, struct COutOfBoundsData *pData, unsigned long ulIndex)
{
        char szLocation[LOCATION_MAXLEN];
        char szIndex[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szIndex, NUMBER_MAXLEN, pData->mIndexType, ulIndex);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, index %s is out of range for type %s\n",
               szLocation, szIndex, pData->mArrayType->mTypeName);
}
 
static void
HandleShiftOutOfBounds(bool isFatal, struct CShiftOutOfBoundsData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
        char szLocation[LOCATION_MAXLEN];
        char szLHS[NUMBER_MAXLEN];
        char szRHS[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szLHS, NUMBER_MAXLEN, pData->mLHSType, ulLHS);
        DeserializeNumber(szLocation, szRHS, NUMBER_MAXLEN, pData->mRHSType, ulRHS);
 
        if (isNegativeNumber(szLocation, pData->mRHSType, ulRHS))
                Report(isFatal, "UBSan: Undefined Behavior in %s, shift exponent %s is negative\n",
                       szLocation, szRHS);
        else if (isShiftExponentTooLarge(szLocation, pData->mRHSType, ulRHS, zDeserializeTypeWidth(pData->mLHSType)))
                Report(isFatal, "UBSan: Undefined Behavior in %s, shift exponent %s is too large for %zu-bit type %s\n",
                       szLocation, szRHS, zDeserializeTypeWidth(pData->mLHSType), pData->mLHSType->mTypeName);
        else if (isNegativeNumber(szLocation, pData->mLHSType, ulLHS))
                Report(isFatal, "UBSan: Undefined Behavior in %s, left shift of negative value %s\n",
                       szLocation, szLHS);
        else
                Report(isFatal, "UBSan: Undefined Behavior in %s, left shift of %s by %s places cannot be represented in type %s\n",
                       szLocation, szLHS, szRHS, pData->mLHSType->mTypeName);
}
 
static void
HandleLoadInvalidValue(bool isFatal, struct CInvalidValueData *pData, unsigned long ulValue)
{
        char szLocation[LOCATION_MAXLEN];
        char szValue[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szValue, NUMBER_MAXLEN, pData->mType, ulValue);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, load of value %s is not a valid value for type %s\n",
               szLocation, szValue, pData->mType->mTypeName);
}
 
static void
HandleInvalidBuiltin(bool isFatal, struct CInvalidBuiltinData *pData)
{
        char szLocation[LOCATION_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, passing zero to %s, which is not a valid argument\n",
               szLocation, DeserializeBuiltinCheckKind(pData->mKind));
}
 
static void
HandleFunctionTypeMismatch(bool isFatal, struct CFunctionTypeMismatchData *pData, unsigned long ulFunction)
{
        char szLocation[LOCATION_MAXLEN];
 
        /*
         * There is no a portable C solution to translate an address of a
         * function to its name. On the cost of getting this routine simple
         * and portable without ifdefs between the userland and the kernel
         * just print the address of the function as-is.
         *
         * For better diagnostic messages in the userland, users shall use
         * the full upstream version shipped along with the compiler toolchain.
         */
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, call to function %#lx through pointer to incorrect function type %s\n",
              szLocation, ulFunction, pData->mType->mTypeName);
}
 
static void
HandleCFIBadType(bool isFatal, struct CCFICheckFailData *pData, unsigned long ulVtable, bool *bValidVtable, bool *FromUnrecoverableHandler, unsigned long *ProgramCounter, unsigned long *FramePointer)
{
        char szLocation[LOCATION_MAXLEN];
 
        /*
         * This is a minimal implementation without diving into C++
         * specifics and (Itanium) ABI deserialization.
         */
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        if (pData->mCheckKind == CFI_ICALL || pData->mCheckKind == CFI_VMFCALL) {
                Report(isFatal, "UBSan: Undefined Behavior in %s, control flow integrity check for type %s failed during %s (vtable address %#lx)\n",
                      szLocation, pData->mType->mTypeName, DeserializeCFICheckKind(pData->mCheckKind), ulVtable);
        } else {
                Report(isFatal || FromUnrecoverableHandler, "UBSan: Undefined Behavior in %s, control flow integrity check for type %s failed during %s (vtable address %#lx; %s vtable; from %s handler; Program Counter %#lx; Frame Pointer %#lx)\n",
                      szLocation, pData->mType->mTypeName, DeserializeCFICheckKind(pData->mCheckKind), ulVtable, *bValidVtable ? "valid" : "invalid", *FromUnrecoverableHandler ? "unrecoverable" : "recoverable", *ProgramCounter, *FramePointer);
        }
}
 
static void
HandleDynamicTypeCacheMiss(bool isFatal, struct CDynamicTypeCacheMissData *pData, unsigned long ulPointer, unsigned long ulHash)
{
#if 0
        char szLocation[LOCATION_MAXLEN];
 
        /*
         * Unimplemented.
         *
         * This UBSan handler is special as the check has to be impelemented
         * in an implementation. In order to handle it there is need to
         * introspect into C++ ABI internals (RTTI) and use low-level
         * C++ runtime interfaces.
         */
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, %s address %#lx which might not point to an object of type %s\n"
              szLocation, DeserializeTypeCheckKind(pData->mTypeCheckKind), ulPointer, pData->mType);
#endif
}
 
static void
HandleFloatCastOverflow(bool isFatal, struct CFloatCastOverflowData *pData, unsigned long ulFrom)
{
        char szLocation[LOCATION_MAXLEN];
        char szFrom[NUMBER_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        DeserializeNumber(szLocation, szFrom, NUMBER_MAXLEN, pData->mFromType, ulFrom);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, %s (of type %s) is outside the range of representable values of type %s\n",
               szLocation, szFrom, pData->mFromType->mTypeName, pData->mToType->mTypeName);
}
 
static void
HandleMissingReturn(bool isFatal, struct CUnreachableData *pData)
{
        char szLocation[LOCATION_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, execution reached the end of a value-returning function without returning a value\n",
               szLocation);
}
 
static void
HandleNonnullArg(bool isFatal, struct CNonNullArgData *pData)
{
        char szLocation[LOCATION_MAXLEN];
        char szAttributeLocation[LOCATION_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
        if (pData->mAttributeLocation.mFilename)
                DeserializeLocation(szAttributeLocation, LOCATION_MAXLEN, &pData->mAttributeLocation);
        else
                szAttributeLocation[0] = '\0';
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, null pointer passed as argument %d, which is declared to never be null%s%s\n",
               szLocation, pData->mArgIndex, pData->mAttributeLocation.mFilename ? ", nonnull/_Nonnull specified in " : "", szAttributeLocation);
}
 
static void
HandleNonnullReturn(bool isFatal, struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer)
{
        char szLocation[LOCATION_MAXLEN];
        char szAttributeLocation[LOCATION_MAXLEN];
 
        ASSERT(pData);
        ASSERT(pLocationPointer);
 
        if (isAlreadyReported(pLocationPointer))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, pLocationPointer);
        if (pData->mAttributeLocation.mFilename)
                DeserializeLocation(szAttributeLocation, LOCATION_MAXLEN, &pData->mAttributeLocation);
        else
                szAttributeLocation[0] = '\0';
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, null pointer returned from function declared to never return null%s%s\n",
               szLocation, pData->mAttributeLocation.mFilename ? ", nonnull/_Nonnull specified in " : "", szAttributeLocation);
}
 
static void
HandlePointerOverflow(bool isFatal, struct CPointerOverflowData *pData, unsigned long ulBase, unsigned long ulResult)
{
        char szLocation[LOCATION_MAXLEN];
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        Report(isFatal, "UBSan: Undefined Behavior in %s, pointer expression with base %#lx overflowed to %#lx\n",
               szLocation, ulBase, ulResult);
}
 
static void
HandleAlignmentAssumption(bool isFatal, struct CAlignmentAssumptionData *pData, unsigned long ulPointer, unsigned long ulAlignment, unsigned long ulOffset)
{
        char szLocation[LOCATION_MAXLEN];
        char szAssumptionLocation[LOCATION_MAXLEN];
        unsigned long ulRealPointer;
 
        ASSERT(pData);
 
        if (isAlreadyReported(&pData->mLocation))
                return;
 
        DeserializeLocation(szLocation, LOCATION_MAXLEN, &pData->mLocation);
 
        ulRealPointer = ulPointer - ulOffset;
 
        if (pData->mAssumptionLocation.mFilename != NULL) {
                DeserializeLocation(szAssumptionLocation, LOCATION_MAXLEN,
                    &pData->mAssumptionLocation);
                Report(isFatal, "UBSan: Undefined Behavior in %s, alignment assumption of %#lx for pointer %#lx (offset %#lx), assumption made in %s\n",
                    szLocation, ulAlignment, ulRealPointer, ulOffset,
                    szAssumptionLocation);
        } else {
                Report(isFatal, "UBSan: Undefined Behavior in %s, alignment assumption of %#lx for pointer %#lx (offset %#lx)\n",
                    szLocation, ulAlignment, ulRealPointer, ulOffset);
        }
}
 
/* Definions of public symbols emitted by the instrumentation code */
void
__ubsan_handle_add_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(false, pData, ulLHS, ulRHS, PLUS_STRING);
}
 
void
__ubsan_handle_add_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(true, pData, ulLHS, ulRHS, PLUS_STRING);
}
 
void
__ubsan_handle_alignment_assumption(struct CAlignmentAssumptionData *pData, unsigned long ulPointer, unsigned long ulAlignment, unsigned long ulOffset)
{
 
        ASSERT(pData);
 
        HandleAlignmentAssumption(false, pData, ulPointer, ulAlignment, ulOffset);
}
 
void
__ubsan_handle_alignment_assumption_abort(struct CAlignmentAssumptionData *pData, unsigned long ulPointer, unsigned long ulAlignment, unsigned long ulOffset)
{
 
        ASSERT(pData);
 
        HandleAlignmentAssumption(true, pData, ulPointer, ulAlignment, ulOffset);
}
 
void
__ubsan_handle_builtin_unreachable(struct CUnreachableData *pData)
{
 
        ASSERT(pData);
 
        HandleBuiltinUnreachable(true, pData);
}
 
void
__ubsan_handle_cfi_bad_type(struct CCFICheckFailData *pData, unsigned long ulVtable, bool bValidVtable, bool FromUnrecoverableHandler, unsigned long ProgramCounter, unsigned long FramePointer)
{
 
        ASSERT(pData);
 
        HandleCFIBadType(false, pData, ulVtable, &bValidVtable, &FromUnrecoverableHandler, &ProgramCounter, &FramePointer);
}
 
void
__ubsan_handle_cfi_check_fail(struct CCFICheckFailData *pData, unsigned long ulValue, unsigned long ulValidVtable)
{
 
        ASSERT(pData);
 
        HandleCFIBadType(false, pData, ulValue, 0, 0, 0, 0);
}
 
void
__ubsan_handle_cfi_check_fail_abort(struct CCFICheckFailData *pData, unsigned long ulValue, unsigned long ulValidVtable)
{
 
        ASSERT(pData);
 
        HandleCFIBadType(true, pData, ulValue, 0, 0, 0, 0);
}
 
void
__ubsan_handle_divrem_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(false, pData, ulLHS, ulRHS, DIVREM_STRING);
}
 
void
__ubsan_handle_divrem_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(true, pData, ulLHS, ulRHS, DIVREM_STRING);
}
 
void
__ubsan_handle_dynamic_type_cache_miss(struct CDynamicTypeCacheMissData *pData, unsigned long ulPointer, unsigned long ulHash)
{
 
        ASSERT(pData);
 
        HandleDynamicTypeCacheMiss(false, pData, ulPointer, ulHash);
}
 
void
__ubsan_handle_dynamic_type_cache_miss_abort(struct CDynamicTypeCacheMissData *pData, unsigned long ulPointer, unsigned long ulHash)
{
 
        ASSERT(pData);
 
        HandleDynamicTypeCacheMiss(false, pData, ulPointer, ulHash);
}
 
void
__ubsan_handle_float_cast_overflow(struct CFloatCastOverflowData *pData, unsigned long ulFrom)
{
 
        ASSERT(pData);
 
        HandleFloatCastOverflow(false, pData, ulFrom);
}
 
void
__ubsan_handle_float_cast_overflow_abort(struct CFloatCastOverflowData *pData, unsigned long ulFrom)
{
 
        ASSERT(pData);
 
        HandleFloatCastOverflow(true, pData, ulFrom);
}
 
void
__ubsan_handle_function_type_mismatch(struct CFunctionTypeMismatchData *pData, unsigned long ulFunction)
{
 
        ASSERT(pData);
 
        HandleFunctionTypeMismatch(false, pData, ulFunction);
}
 
void
__ubsan_handle_function_type_mismatch_abort(struct CFunctionTypeMismatchData *pData, unsigned long ulFunction)
{
 
        ASSERT(pData);
 
        HandleFunctionTypeMismatch(false, pData, ulFunction);
}
 
void
__ubsan_handle_invalid_builtin(struct CInvalidBuiltinData *pData)
{
 
        ASSERT(pData);
 
        HandleInvalidBuiltin(true, pData);
}
 
void
__ubsan_handle_invalid_builtin_abort(struct CInvalidBuiltinData *pData)
{
 
        ASSERT(pData);
 
        HandleInvalidBuiltin(true, pData);
}
 
void
__ubsan_handle_load_invalid_value(struct CInvalidValueData *pData, unsigned long ulValue)
{
 
        ASSERT(pData);
 
        HandleLoadInvalidValue(false, pData, ulValue);
}
 
void
__ubsan_handle_load_invalid_value_abort(struct CInvalidValueData *pData, unsigned long ulValue)
{
 
        ASSERT(pData);
 
        HandleLoadInvalidValue(true, pData, ulValue);
}
 
void
__ubsan_handle_missing_return(struct CUnreachableData *pData)
{
 
        ASSERT(pData);
 
        HandleMissingReturn(true, pData);
}
 
void
__ubsan_handle_mul_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(false, pData, ulLHS, ulRHS, MUL_STRING);
}
 
void
__ubsan_handle_mul_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(true, pData, ulLHS, ulRHS, MUL_STRING);
}
 
void
__ubsan_handle_negate_overflow(struct COverflowData *pData, unsigned long ulOldValue)
{
 
        ASSERT(pData);
 
        HandleNegateOverflow(false, pData, ulOldValue);
}
 
void
__ubsan_handle_negate_overflow_abort(struct COverflowData *pData, unsigned long ulOldValue)
{
 
        ASSERT(pData);
 
        HandleNegateOverflow(true, pData, ulOldValue);
}
 
void
__ubsan_handle_nonnull_arg(struct CNonNullArgData *pData)
{
 
        ASSERT(pData);
 
        HandleNonnullArg(false, pData);
}
 
void
__ubsan_handle_nonnull_arg_abort(struct CNonNullArgData *pData)
{
 
        ASSERT(pData);
 
        HandleNonnullArg(true, pData);
}
 
void
__ubsan_handle_nonnull_return_v1(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer)
{
 
        ASSERT(pData);
        ASSERT(pLocationPointer);
 
        HandleNonnullReturn(false, pData, pLocationPointer);
}
 
void
__ubsan_handle_nonnull_return_v1_abort(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer)
{
 
        ASSERT(pData);
        ASSERT(pLocationPointer);
 
        HandleNonnullReturn(true, pData, pLocationPointer);
}
 
void
__ubsan_handle_nullability_arg(struct CNonNullArgData *pData)
{
 
        ASSERT(pData);
 
        HandleNonnullArg(false, pData);
}
 
void
__ubsan_handle_nullability_arg_abort(struct CNonNullArgData *pData)
{
 
        ASSERT(pData);
 
        HandleNonnullArg(true, pData);
}
 
void
__ubsan_handle_nullability_return_v1(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer)
{
 
        ASSERT(pData);
        ASSERT(pLocationPointer);
 
        HandleNonnullReturn(false, pData, pLocationPointer);
}
 
void
__ubsan_handle_nullability_return_v1_abort(struct CNonNullReturnData *pData, struct CSourceLocation *pLocationPointer)
{
 
        ASSERT(pData);
        ASSERT(pLocationPointer);
 
        HandleNonnullReturn(true, pData, pLocationPointer);
}
 
void
__ubsan_handle_out_of_bounds(struct COutOfBoundsData *pData, unsigned long ulIndex)
{
 
        ASSERT(pData);
 
        HandleOutOfBounds(false, pData, ulIndex);
}
 
void
__ubsan_handle_out_of_bounds_abort(struct COutOfBoundsData *pData, unsigned long ulIndex)
{
 
        ASSERT(pData);
 
        HandleOutOfBounds(true, pData, ulIndex);
}
 
void
__ubsan_handle_pointer_overflow(struct CPointerOverflowData *pData, unsigned long ulBase, unsigned long ulResult)
{
 
        ASSERT(pData);
 
        HandlePointerOverflow(false, pData, ulBase, ulResult);
}
 
void
__ubsan_handle_pointer_overflow_abort(struct CPointerOverflowData *pData, unsigned long ulBase, unsigned long ulResult)
{
 
        ASSERT(pData);
 
        HandlePointerOverflow(true, pData, ulBase, ulResult);
}
 
void
__ubsan_handle_shift_out_of_bounds(struct CShiftOutOfBoundsData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleShiftOutOfBounds(false, pData, ulLHS, ulRHS);
}
 
void
__ubsan_handle_shift_out_of_bounds_abort(struct CShiftOutOfBoundsData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleShiftOutOfBounds(true, pData, ulLHS, ulRHS);
}
 
void
__ubsan_handle_sub_overflow(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(false, pData, ulLHS, ulRHS, MINUS_STRING);
}
 
void
__ubsan_handle_sub_overflow_abort(struct COverflowData *pData, unsigned long ulLHS, unsigned long ulRHS)
{
 
        ASSERT(pData);
 
        HandleOverflow(true, pData, ulLHS, ulRHS, MINUS_STRING);
}
 
void
__ubsan_handle_type_mismatch(struct CTypeMismatchData *pData, unsigned long ulPointer)
{
 
        ASSERT(pData);
 
        HandleTypeMismatch(false, &pData->mLocation, pData->mType, pData->mLogAlignment, pData->mTypeCheckKind, ulPointer);
}
 
void
__ubsan_handle_type_mismatch_abort(struct CTypeMismatchData *pData, unsigned long ulPointer)
{
 
        ASSERT(pData);
 
        HandleTypeMismatch(true, &pData->mLocation, pData->mType, pData->mLogAlignment, pData->mTypeCheckKind, ulPointer);
}
 
void
__ubsan_handle_type_mismatch_v1(struct CTypeMismatchData_v1 *pData, unsigned long ulPointer)
{
 
        ASSERT(pData);
 
        HandleTypeMismatch(false, &pData->mLocation, pData->mType, __BIT(pData->mLogAlignment), pData->mTypeCheckKind, ulPointer);
}
 
void
__ubsan_handle_type_mismatch_v1_abort(struct CTypeMismatchData_v1 *pData, unsigned long ulPointer)
{
 
        ASSERT(pData);
 
        HandleTypeMismatch(true, &pData->mLocation, pData->mType, __BIT(pData->mLogAlignment), pData->mTypeCheckKind, ulPointer);
}
 
void
__ubsan_handle_vla_bound_not_positive(struct CVLABoundData *pData, unsigned long ulBound)
{
 
        ASSERT(pData);
 
        HandleVlaBoundNotPositive(false, pData, ulBound);
}
 
void
__ubsan_handle_vla_bound_not_positive_abort(struct CVLABoundData *pData, unsigned long ulBound)
{
 
        ASSERT(pData);
 
        HandleVlaBoundNotPositive(true, pData, ulBound);
}
 
void
__ubsan_get_current_report_data(const char **ppOutIssueKind, const char **ppOutMessage, const char **ppOutFilename, uint32_t *pOutLine, uint32_t *pOutCol, char **ppOutMemoryAddr)
{
        /*
         * Unimplemented.
         *
         * The __ubsan_on_report() feature is non trivial to implement in a
         * shared code between the kernel and userland. It's also opening
         * new sets of potential problems as we are not expected to slow down
         * execution of certain kernel subsystems (synchronization issues,
         * interrupt handling etc).
         *
         * A proper solution would need probably a lock-free bounded queue built
         * with atomic operations with the property of miltiple consumers and
         * multiple producers. Maintaining and validating such code is not
         * worth the effort.
         *
         * A legitimate user - besides testing framework - is a debugger plugin
         * intercepting reports from the UBSan instrumentation. For such
         * scenarios it is better to run the Clang/GCC version.
         */
}
 
/* Local utility functions */
 
static void
Report(bool isFatal, const char *pFormat, ...)
{
        va_list ap;
 
        ASSERT(pFormat);
 
        va_start(ap, pFormat);
#if defined(_KERNEL)
        if (isFatal)
                vpanic(pFormat, ap);
        else
                vprintf(pFormat, ap);
#else
        if (ubsan_flags == -1) {
                char buf[1024];
                char *p;
 
                ubsan_flags = UBSAN_STDERR;
 
                if (getenv_r("LIBC_UBSAN", buf, sizeof(buf)) != -1) {
                        for (p = buf; *p; p++) {
                                switch (*p) {
                                case 'a':
                                        SET(ubsan_flags, UBSAN_ABORT);
                                        break;
                                case 'A':
                                        CLR(ubsan_flags, UBSAN_ABORT);
                                        break;
                                case 'e':
                                        SET(ubsan_flags, UBSAN_STDERR);
                                        break;
                                case 'E':
                                        CLR(ubsan_flags, UBSAN_STDERR);
                                        break;
                                case 'l':
                                        SET(ubsan_flags, UBSAN_SYSLOG);
                                        break;
                                case 'L':
                                        CLR(ubsan_flags, UBSAN_SYSLOG);
                                        break;
                                case 'o':
                                        SET(ubsan_flags, UBSAN_STDOUT);
                                        break;
                                case 'O':
                                        CLR(ubsan_flags, UBSAN_STDOUT);
                                        break;
                                default:
                                        break;
                                }
                        }
                }
        }
 
        // The *v*print* functions can flush the va_list argument.
        // Create a local copy for each call to prevent invalid read.
        if (ISSET(ubsan_flags, UBSAN_STDOUT)) {
                va_list tmp;
                va_copy(tmp, ap);
                vprintf(pFormat, tmp);
                va_end(tmp);
                fflush(stdout);
        }
        if (ISSET(ubsan_flags, UBSAN_STDERR)) {
                va_list tmp;
                va_copy(tmp, ap);
                vfprintf(stderr, pFormat, tmp);
                va_end(tmp);
                fflush(stderr);
        }
        if (ISSET(ubsan_flags, UBSAN_SYSLOG)) {
                va_list tmp;
                va_copy(tmp, ap);
                struct syslog_data SyslogData = SYSLOG_DATA_INIT;
                ubsan_vsyslog(LOG_DEBUG | LOG_USER, &SyslogData, pFormat, tmp);
                va_end(tmp);
        }
        if (isFatal || ISSET(ubsan_flags, UBSAN_ABORT)) {
                abort();
                /* NOTREACHED */
        }
#endif
        va_end(ap);
}
 
static bool
isAlreadyReported(struct CSourceLocation *pLocation)
{
        /*
         * This code is shared between libc, kernel and standalone usage.
         * It shall work in early bootstrap phase of both of them.
         */
 
        uint32_t siOldValue;
        volatile uint32_t *pLine;
 
        ASSERT(pLocation);
 
        pLine = &pLocation->mLine;
 
        do {
                siOldValue = *pLine;
        } while (__sync_val_compare_and_swap(pLine, siOldValue, siOldValue | ACK_REPORTED) != siOldValue);
 
        return ISSET(siOldValue, ACK_REPORTED);
}
 
static size_t
zDeserializeTypeWidth(struct CTypeDescriptor *pType)
{
        size_t zWidth = 0;
 
        ASSERT(pType);
 
        switch (pType->mTypeKind) {
        case KIND_INTEGER:
                zWidth = __BIT(__SHIFTOUT(pType->mTypeInfo, ~NUMBER_SIGNED_BIT));
                break;
        case KIND_FLOAT:
                zWidth = pType->mTypeInfo;
                break;
        default:
                Report(true, "UBSan: Unknown variable type %#04" PRIx16 "\n", pType->mTypeKind);
                /* NOTREACHED */
        }
 
        /* Invalid width will be transformed to 0 */
        ASSERT(zWidth > 0);
 
        return zWidth;
}
 
static void
DeserializeLocation(char *pBuffer, size_t zBUfferLength, struct CSourceLocation *pLocation)
{
 
        ASSERT(pLocation);
        ASSERT(pLocation->mFilename);
 
        snprintf(pBuffer, zBUfferLength, "%s:%" PRIu32 ":%" PRIu32, pLocation->mFilename, pLocation->mLine & (uint32_t)~ACK_REPORTED, pLocation->mColumn);
}
 
#ifdef __SIZEOF_INT128__
static void
DeserializeUINT128(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, __uint128_t U128)
{
        char szBuf[3]; /* 'XX\0' */
        char rgNumber[sizeof(ulongest)];
        ssize_t zI;
 
        memcpy(rgNumber, &U128, sizeof(U128));
 
        strlcpy(pBuffer, "Undecoded-128-bit-Integer-Type (0x", zBUfferLength);
#if BYTE_ORDER == LITTLE_ENDIAN
        for (zI = sizeof(ulongest) - 1; zI >= 0; zI--) {
#else
        for (zI = 0; zI < (ssize_t)sizeof(ulongest); zI++) {
#endif
                snprintf(szBuf, sizeof(szBuf), "%02" PRIx8, rgNumber[zI]);
                strlcat(pBuffer, szBuf, zBUfferLength);
        }
        strlcat(pBuffer, ")", zBUfferLength);
}
#endif
 
static void
DeserializeNumberSigned(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, longest L)
{
 
        ASSERT(pBuffer);
        ASSERT(zBUfferLength > 0);
        ASSERT(pType);
        ASSERT(ISSET(pType->mTypeInfo, NUMBER_SIGNED_BIT));
 
        switch (zDeserializeTypeWidth(pType)) {
        default:
                ASSERT(0 && "Invalid codepath");
                /* NOTREACHED */
#ifdef __SIZEOF_INT128__
        case WIDTH_128:
                DeserializeUINT128(pBuffer, zBUfferLength, pType, STATIC_CAST(__uint128_t, L));
                break;
#endif
        case WIDTH_64:
        case WIDTH_32:
        case WIDTH_16:
        case WIDTH_8:
                snprintf(pBuffer, zBUfferLength, "%" PRId64, STATIC_CAST(int64_t, L));
                break;
        }
}
 
static void
DeserializeNumberUnsigned(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, ulongest L)
{
 
        ASSERT(pBuffer);
        ASSERT(zBUfferLength > 0);
        ASSERT(pType);
        ASSERT(!ISSET(pType->mTypeInfo, NUMBER_SIGNED_BIT));
 
        switch (zDeserializeTypeWidth(pType)) {
        default:
                ASSERT(0 && "Invalid codepath");
                /* NOTREACHED */
#ifdef __SIZEOF_INT128__
        case WIDTH_128:
                DeserializeUINT128(pBuffer, zBUfferLength, pType, STATIC_CAST(__uint128_t, L));
                break;
#endif
        case WIDTH_64:
        case WIDTH_32:
        case WIDTH_16:
        case WIDTH_8:
                snprintf(pBuffer, zBUfferLength, "%" PRIu64, STATIC_CAST(uint64_t, L));
                break;
        }
}
 
#ifndef _KERNEL
static void
DeserializeFloatOverPointer(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long *pNumber)
{
        double D;
#ifdef __HAVE_LONG_DOUBLE
        long double LD;
#endif
 
        ASSERT(pBuffer);
        ASSERT(zBUfferLength > 0);
        ASSERT(pType);
        ASSERT(pNumber);
        /*
         * This function handles 64-bit number over a pointer on 32-bit CPUs.
         */
        ASSERT((sizeof(*pNumber) * CHAR_BIT < WIDTH_64) || (zDeserializeTypeWidth(pType) >= WIDTH_64));
        ASSERT(sizeof(D) == sizeof(uint64_t));
#ifdef __HAVE_LONG_DOUBLE
        ASSERT(sizeof(LD) > sizeof(uint64_t));
#endif
 
        switch (zDeserializeTypeWidth(pType)) {
#ifdef __HAVE_LONG_DOUBLE
        case WIDTH_128:
        case WIDTH_96:
        case WIDTH_80:
                memcpy(&LD, pNumber, sizeof(long double));
                snprintf(pBuffer, zBUfferLength, "%Lg", LD);
                break;
#endif
        case WIDTH_64:
                memcpy(&D, pNumber, sizeof(double));
                snprintf(pBuffer, zBUfferLength, "%g", D);
                break;
        }
}
 
static void
DeserializeFloatInlined(char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long ulNumber)
{
        float F;
        double D;
        uint32_t U32;
 
        ASSERT(pBuffer);
        ASSERT(zBUfferLength > 0);
        ASSERT(pType);
        ASSERT(sizeof(F) == sizeof(uint32_t));
        ASSERT(sizeof(D) == sizeof(uint64_t));
 
        switch (zDeserializeTypeWidth(pType)) {
        case WIDTH_64:
                memcpy(&D, &ulNumber, sizeof(double));
                snprintf(pBuffer, zBUfferLength, "%g", D);
                break;
        case WIDTH_32:
                /*
                 * On supported platforms sizeof(float)==sizeof(uint32_t)
                 * unsigned long is either 32 or 64-bit, cast it to 32-bit
                 * value in order to call memcpy(3) in an Endian-aware way.
                 */
                U32 = STATIC_CAST(uint32_t, ulNumber);
                memcpy(&F, &U32, sizeof(float));
                snprintf(pBuffer, zBUfferLength, "%g", F);
                break;
        case WIDTH_16:
                snprintf(pBuffer, zBUfferLength, "Undecoded-16-bit-Floating-Type (%#04" PRIx16 ")", STATIC_CAST(uint16_t, ulNumber));
                break;
        }
}
#endif
 
static longest
llliGetNumber(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber)
{
        size_t zNumberWidth;
        longest L = 0;
 
        ASSERT(szLocation);
        ASSERT(pType);
 
        zNumberWidth = zDeserializeTypeWidth(pType);
        switch (zNumberWidth) {
        default:
                Report(true, "UBSan: Unexpected %zu-Bit Type in %s\n", zNumberWidth, szLocation);
                /* NOTREACHED */
        case WIDTH_128:
#ifdef __SIZEOF_INT128__
                memcpy(&L, REINTERPRET_CAST(longest *, ulNumber), sizeof(longest));
#else
                Report(true, "UBSan: Unexpected 128-Bit Type in %s\n", szLocation);
                /* NOTREACHED */
#endif
                break;
        case WIDTH_64:
                if (sizeof(ulNumber) * CHAR_BIT < WIDTH_64) {
                        L = *REINTERPRET_CAST(int64_t *, ulNumber);
                } else {
                        L = STATIC_CAST(int64_t, STATIC_CAST(uint64_t, ulNumber));
                }
                break;
        case WIDTH_32:
                L = STATIC_CAST(int32_t, STATIC_CAST(uint32_t, ulNumber));
                break;
        case WIDTH_16:
                L = STATIC_CAST(int16_t, STATIC_CAST(uint16_t, ulNumber));
                break;
        case WIDTH_8:
                L = STATIC_CAST(int8_t, STATIC_CAST(uint8_t, ulNumber));
                break;
        }
 
        return L;
}
 
static ulongest
llluGetNumber(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber)
{
        size_t zNumberWidth;
        ulongest UL = 0;
 
        ASSERT(pType);
 
        zNumberWidth = zDeserializeTypeWidth(pType);
        switch (zNumberWidth) {
        default:
                Report(true, "UBSan: Unexpected %zu-Bit Type in %s\n", zNumberWidth, szLocation);
                /* NOTREACHED */
        case WIDTH_128:
#ifdef __SIZEOF_INT128__
                memcpy(&UL, REINTERPRET_CAST(ulongest *, ulNumber), sizeof(ulongest));
                break;
#else
                Report(true, "UBSan: Unexpected 128-Bit Type in %s\n", szLocation);
                /* NOTREACHED */
#endif
        case WIDTH_64:
                if (sizeof(ulNumber) * CHAR_BIT < WIDTH_64) {
                        UL = *REINTERPRET_CAST(uint64_t *, ulNumber);
                        break;
                }
                /* FALLTHROUGH */
        case WIDTH_32:
                /* FALLTHROUGH */
        case WIDTH_16:
                /* FALLTHROUGH */
        case WIDTH_8:
                UL = ulNumber;
                break;
        }
 
        return UL;
}
 
#ifndef _KERNEL
static void
DeserializeNumberFloat(char *szLocation, char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long ulNumber)
{
        size_t zNumberWidth;
 
        ASSERT(szLocation);
        ASSERT(pBuffer);
        ASSERT(zBUfferLength > 0);
        ASSERT(pType);
        ASSERT(pType->mTypeKind == KIND_FLOAT);
 
        zNumberWidth = zDeserializeTypeWidth(pType);
        switch (zNumberWidth) {
        default:
                Report(true, "UBSan: Unexpected %zu-Bit Type in %s\n", zNumberWidth, szLocation);
                /* NOTREACHED */
#ifdef __HAVE_LONG_DOUBLE
        case WIDTH_128:
        case WIDTH_96:
        case WIDTH_80:
                DeserializeFloatOverPointer(pBuffer, zBUfferLength, pType, REINTERPRET_CAST(unsigned long *, ulNumber));
                break;
#endif
        case WIDTH_64:
                if (sizeof(ulNumber) * CHAR_BIT < WIDTH_64) {
                        DeserializeFloatOverPointer(pBuffer, zBUfferLength, pType, REINTERPRET_CAST(unsigned long *, ulNumber));
                        break;
                }
        case WIDTH_32:
        case WIDTH_16:
                DeserializeFloatInlined(pBuffer, zBUfferLength, pType, ulNumber);
                break;
        }
}
#endif
 
static void
DeserializeNumber(char *szLocation, char *pBuffer, size_t zBUfferLength, struct CTypeDescriptor *pType, unsigned long ulNumber)
{
 
        ASSERT(szLocation);
        ASSERT(pBuffer);
        ASSERT(zBUfferLength > 0);
        ASSERT(pType);
 
        switch(pType->mTypeKind) {
        case KIND_INTEGER:
                if (ISSET(pType->mTypeInfo, NUMBER_SIGNED_BIT)) {
                        longest L = llliGetNumber(szLocation, pType, ulNumber);
                        DeserializeNumberSigned(pBuffer, zBUfferLength, pType, L);
                } else {
                        ulongest UL = llluGetNumber(szLocation, pType, ulNumber);
                        DeserializeNumberUnsigned(pBuffer, zBUfferLength, pType, UL);
                }
                break;
        case KIND_FLOAT:
#ifdef _KERNEL
                Report(true, "UBSan: Unexpected Float Type in %s\n", szLocation);
                /* NOTREACHED */
#else
                DeserializeNumberFloat(szLocation, pBuffer, zBUfferLength, pType, ulNumber);
#endif
                break;
        case KIND_UNKNOWN:
                Report(true, "UBSan: Unknown Type in %s\n", szLocation);
                /* NOTREACHED */
                break;
        }
}
 
static const char *
DeserializeTypeCheckKind(uint8_t hhuTypeCheckKind)
{
        const char *rgczTypeCheckKinds[] = {
                "load of",
                "store to",
                "reference binding to",
                "member access within",
                "member call on",
                "constructor call on",
                "downcast of",
                "downcast of",
                "upcast of",
                "cast to virtual base of",
                "_Nonnull binding to",
                "dynamic operation on"
        };
 
        ASSERT(__arraycount(rgczTypeCheckKinds) > hhuTypeCheckKind);
 
        return rgczTypeCheckKinds[hhuTypeCheckKind];
}
 
static const char *
DeserializeBuiltinCheckKind(uint8_t hhuBuiltinCheckKind)
{
        const char *rgczBuiltinCheckKinds[] = {
                "ctz()",
                "clz()"
        };
 
        ASSERT(__arraycount(rgczBuiltinCheckKinds) > hhuBuiltinCheckKind);
 
        return rgczBuiltinCheckKinds[hhuBuiltinCheckKind];
}
 
static const char *
DeserializeCFICheckKind(uint8_t hhuCFICheckKind)
{
        const char *rgczCFICheckKinds[] = {
                "virtual call",                                 // CFI_VCALL
                "non-virtual call",                             // CFI_NVCALL
                "base-to-derived cast",                         // CFI_DERIVEDCAST
                "cast to unrelated type",                       // CFI_UNRELATEDCAST
                "indirect function call",                       // CFI_ICALL
                "non-virtual pointer to member function call",  // CFI_NVMFCALL
                "virtual pointer to member function call",      // CFI_VMFCALL
        };
 
        ASSERT(__arraycount(rgczCFICheckKinds) > hhuCFICheckKind);
 
        return rgczCFICheckKinds[hhuCFICheckKind];
}
 
static bool
isNegativeNumber(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber)
{
 
        ASSERT(szLocation);
        ASSERT(pType);
        ASSERT(pType->mTypeKind == KIND_INTEGER);
 
        if (!ISSET(pType->mTypeInfo, NUMBER_SIGNED_BIT))
                return false;
 
        return llliGetNumber(szLocation, pType, ulNumber) < 0;
}
 
static bool
isShiftExponentTooLarge(char *szLocation, struct CTypeDescriptor *pType, unsigned long ulNumber, size_t zWidth)
{
 
        ASSERT(szLocation);
        ASSERT(pType);
        ASSERT(pType->mTypeKind == KIND_INTEGER);
 
        return llluGetNumber(szLocation, pType, ulNumber) >= zWidth;
}