incubator-nuttx/mm/ubsan/ubsan.c

378 lines
11 KiB
C

/****************************************************************************
* mm/ubsan/ubsan.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/compiler.h>
#include <debug.h>
#include <stdio.h>
#include "ubsan.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define IS_ALIGNED(x, a) (((x) & ((a) - 1)) == 0)
/****************************************************************************
* Private Data
****************************************************************************/
static FAR const char *const g_type_check_kinds[] =
{
"load of",
"store to",
"reference binding to",
"member access within",
"member call on",
"constructor call on",
"downcast of",
"downcast of"
};
/****************************************************************************
* Private Functions
****************************************************************************/
static void ubsan_prologue(FAR struct source_location *loc,
FAR const char *reason)
{
_alert("========================================"
"========================================\n");
_alert("UBSAN: %s in %s:%" PRIu32 ":%" PRIu32"\n",
reason, loc->file_name, loc->line, loc->column);
}
static void ubsan_epilogue(void)
{
_alert("========================================"
"========================================\n");
}
static void ubsan_prologue_epilogue(FAR struct source_location *loc,
FAR const char *reason)
{
ubsan_prologue(loc, reason);
ubsan_epilogue();
}
static void handle_null_ptr_deref(FAR struct type_mismatch_data_common *data)
{
ubsan_prologue(data->location, "null-pointer-dereference");
_alert("%s null pointer of type %s\n",
g_type_check_kinds[data->type_check_kind], data->type->type_name);
ubsan_epilogue();
}
static void handle_misaligned_access(
FAR struct type_mismatch_data_common *data, uintptr_t ptr)
{
ubsan_prologue(data->location, "misaligned-access");
_alert("%s misaligned address %p for type %s\n",
g_type_check_kinds[data->type_check_kind], (FAR void *)ptr,
data->type->type_name);
_alert("which requires %ld byte alignment\n", data->alignment);
ubsan_epilogue();
}
static void handle_object_size_mismatch(
FAR struct type_mismatch_data_common *data, uintptr_t ptr)
{
ubsan_prologue(data->location, "object-size-mismatch");
_alert("%s address %p with insufficient space\n",
g_type_check_kinds[data->type_check_kind], (FAR void *)ptr);
_alert("for an object of type %s\n", data->type->type_name);
ubsan_epilogue();
}
static void ubsan_type_mismatch_common(
FAR struct type_mismatch_data_common *data, uintptr_t ptr)
{
if (!ptr)
{
handle_null_ptr_deref(data);
}
else if (data->alignment && !IS_ALIGNED(ptr, data->alignment))
{
handle_misaligned_access(data, ptr);
}
else
{
handle_object_size_mismatch(data, ptr);
}
}
static bool type_is_int(FAR struct type_descriptor *type)
{
return type->type_kind == TYPE_KIND_INT;
}
static bool type_is_signed(FAR struct type_descriptor *type)
{
return type->type_info & 1;
}
static unsigned type_bit_width(FAR struct type_descriptor *type)
{
return 1 << (type->type_info >> 1);
}
static bool is_inline_int(FAR struct type_descriptor *type)
{
unsigned inline_bits = sizeof(uintptr_t) * 8;
unsigned bits = type_bit_width(type);
return bits <= inline_bits;
}
static int64_t get_signed_val(FAR struct type_descriptor *type,
FAR void *val)
{
if (is_inline_int(type))
{
unsigned extra_bits = sizeof(int64_t) * 8 - type_bit_width(type);
uintptr_t ulong_val = (uintptr_t)val;
return ((int64_t)ulong_val) << extra_bits >> extra_bits;
}
return *(FAR int64_t *)val;
}
static bool val_is_negative(FAR struct type_descriptor *type, FAR void *val)
{
return type_is_signed(type) && get_signed_val(type, val) < 0;
}
static uint64_t get_unsigned_val(FAR struct type_descriptor *type,
FAR void *val)
{
if (is_inline_int(type))
{
return (uintptr_t)val;
}
return *(uint64_t *)val;
}
static void val_to_string(FAR char *str, size_t size,
FAR struct type_descriptor *type,
FAR void *value)
{
if (type_is_int(type))
{
if (type_is_signed(type))
{
snprintf(str, size, "%" PRId64, get_signed_val(type, value));
}
else
{
snprintf(str, size, "%" PRIu64, get_unsigned_val(type, value));
}
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
void __ubsan_handle_out_of_bounds(FAR void *data, FAR void *index)
{
FAR struct out_of_bounds_data *info = data;
char index_str[40];
ubsan_prologue(&info->location, "array-index-out-of-bounds");
val_to_string(index_str, sizeof(index_str), info->index_type, index);
_alert("index %s is out of range for type %s\n",
index_str, info->array_type->type_name);
ubsan_epilogue();
}
void __ubsan_handle_shift_out_of_bounds(FAR void *data,
FAR void *lhs, FAR void *rhs)
{
FAR struct shift_out_of_bounds_data *info = data;
FAR struct type_descriptor *rhs_type = info->rhs_type;
FAR struct type_descriptor *lhs_type = info->lhs_type;
char rhs_str[40];
char lhs_str[40];
ubsan_prologue(&info->location, "shift-out-of-bounds");
val_to_string(rhs_str, sizeof(rhs_str), rhs_type, rhs);
val_to_string(lhs_str, sizeof(lhs_str), lhs_type, lhs);
if (val_is_negative(rhs_type, rhs))
{
_alert("shift exponent %s is negative\n", rhs_str);
}
else if (get_unsigned_val(rhs_type, rhs) >= type_bit_width(lhs_type))
{
_alert("shift exponent %s is too large for %u-bit type %s\n",
rhs_str, type_bit_width(lhs_type), lhs_type->type_name);
}
else if (val_is_negative(lhs_type, lhs))
{
_alert("left shift of negative value %s\n", lhs_str);
}
else
{
_alert("left shift of %s by %s places cannot be"
" represented in type %s\n",
lhs_str, rhs_str, lhs_type->type_name);
}
ubsan_epilogue();
}
void __ubsan_handle_divrem_overflow(FAR void *data,
FAR void *lhs, FAR void *rhs)
{
FAR struct overflow_data *info = data;
char rhs_val_str[40];
ubsan_prologue(&info->location, "division-overflow");
val_to_string(rhs_val_str, sizeof(rhs_val_str), info->type, rhs);
if (type_is_signed(info->type) && get_signed_val(info->type, rhs) == -1)
{
_alert("division of %s by -1 cannot be represented in type %s\n",
rhs_val_str, info->type->type_name);
}
else
{
_alert("division by zero\n");
}
}
void __ubsan_handle_alignment_assumption(FAR void *data, uintptr_t ptr,
uintptr_t align, uintptr_t offset)
{
FAR struct alignment_assumption_data *info = data;
uintptr_t real_ptr;
ubsan_prologue(&info->location, "alignment-assumption");
if (offset)
{
_alert("assumption of %zu byte alignment (with offset of %zu byte) for"
" pointer of type %s failed",
align, offset, info->type->type_name);
}
else
{
_alert("assumption of %zu byte alignment for pointer of type %s "
"failed", align, info->type->type_name);
}
real_ptr = ptr - offset;
_alert("%saddress is %lu aligned, misalignment offset is %zu bytes",
offset ? "offset " : "",
1ul << (real_ptr ? ffsl(real_ptr) : 0),
real_ptr & (align - 1));
ubsan_epilogue();
}
void __ubsan_handle_type_mismatch(FAR struct type_mismatch_data *data,
FAR void *ptr)
{
struct type_mismatch_data_common common_data =
{
.location = &data->location,
.type = data->type,
.alignment = data->alignment,
.type_check_kind = data->type_check_kind
};
ubsan_type_mismatch_common(&common_data, (uintptr_t)ptr);
}
void __ubsan_handle_type_mismatch_v1(FAR void *_data, FAR void *ptr)
{
FAR struct type_mismatch_data_v1 *data = _data;
struct type_mismatch_data_common common_data =
{
.location = &data->location,
.type = data->type,
.alignment = 1ul << data->log_alignment,
.type_check_kind = data->type_check_kind
};
ubsan_type_mismatch_common(&common_data, (uintptr_t)ptr);
}
void __ubsan_handle_builtin_unreachable(FAR void *data)
{
ubsan_prologue_epilogue(data, "unreachable");
PANIC();
}
void __ubsan_handle_nonnull_arg(FAR void *data)
{
ubsan_prologue_epilogue(data, "nonnull-arg");
}
void __ubsan_handle_add_overflow(FAR void *data,
FAR void *lhs, FAR void *rhs)
{
ubsan_prologue_epilogue(data, "add-overflow");
}
void __ubsan_handle_sub_overflow(FAR void *data,
FAR void *lhs, FAR void *rhs)
{
ubsan_prologue_epilogue(data, "sub-overflow");
}
void __ubsan_handle_mul_overflow(FAR void *data,
FAR void *lhs, FAR void *rhs)
{
ubsan_prologue_epilogue(data, "mul-overflow");
}
void __ubsan_handle_load_invalid_value(FAR void *data, FAR void *ptr)
{
ubsan_prologue_epilogue(data, "load-invalid-value");
}
void __ubsan_handle_negate_overflow(FAR void *data, FAR void *ptr)
{
ubsan_prologue_epilogue(data, "negate-overflow");
}
void __ubsan_handle_pointer_overflow(FAR void *data,
FAR void *ptr, FAR void *result)
{
ubsan_prologue_epilogue(data, "pointer-overflow");
}