Bug Summary

File:build/source/lldb/source/DataFormatters/VectorType.cpp
Warning:line 285, column 3
Potential leak of memory pointed to by 'synthetic_children'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name VectorType.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/source/build-llvm/tools/clang/stage2-bins -resource-dir /usr/lib/llvm-17/lib/clang/17 -isystem /usr/include/libxml2 -D HAVE_ROUND -D _DEBUG -D _GLIBCXX_ASSERTIONS -D _GNU_SOURCE -D _LIBCPP_ENABLE_ASSERTIONS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/lldb/source/DataFormatters -I /build/source/lldb/source/DataFormatters -I /build/source/lldb/include -I tools/lldb/include -I include -I /build/source/llvm/include -I /usr/include/python3.9 -I /build/source/clang/include -I tools/lldb/../clang/include -I /build/source/lldb/source -I tools/lldb/source -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-17/lib/clang/17/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fmacro-prefix-map=/build/source/= -fcoverage-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fcoverage-prefix-map=/build/source/= -source-date-epoch 1683717183 -O2 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -Wno-deprecated-declarations -Wno-unknown-pragmas -Wno-strict-aliasing -Wno-stringop-truncation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/source/build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/source/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2023-05-10-133810-16478-1 -x c++ /build/source/lldb/source/DataFormatters/VectorType.cpp
1//===-- VectorType.cpp ----------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "lldb/DataFormatters/VectorType.h"
10
11#include "lldb/Core/ValueObject.h"
12#include "lldb/DataFormatters/FormattersHelpers.h"
13#include "lldb/Symbol/CompilerType.h"
14#include "lldb/Symbol/TypeSystem.h"
15#include "lldb/Target/Target.h"
16
17#include "lldb/Utility/LLDBAssert.h"
18#include "lldb/Utility/Log.h"
19#include <optional>
20
21using namespace lldb;
22using namespace lldb_private;
23using namespace lldb_private::formatters;
24
25static CompilerType GetCompilerTypeForFormat(lldb::Format format,
26 CompilerType element_type,
27 TypeSystemSP type_system) {
28 lldbassert(type_system && "type_system needs to be not NULL")lldb_private::lldb_assert(static_cast<bool>(type_system
&& "type_system needs to be not NULL"), "type_system && \"type_system needs to be not NULL\""
, __FUNCTION__, "lldb/source/DataFormatters/VectorType.cpp", 28
);
29 if (!type_system)
30 return {};
31
32 switch (format) {
33 case lldb::eFormatAddressInfo:
34 case lldb::eFormatPointer:
35 return type_system->GetBuiltinTypeForEncodingAndBitSize(
36 eEncodingUint, 8 * type_system->GetPointerByteSize());
37
38 case lldb::eFormatBoolean:
39 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeBool);
40
41 case lldb::eFormatBytes:
42 case lldb::eFormatBytesWithASCII:
43 case lldb::eFormatChar:
44 case lldb::eFormatCharArray:
45 case lldb::eFormatCharPrintable:
46 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeChar);
47
48 case lldb::eFormatComplex /* lldb::eFormatComplexFloat */:
49 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeFloatComplex);
50
51 case lldb::eFormatCString:
52 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeChar)
53 .GetPointerType();
54
55 case lldb::eFormatFloat:
56 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeFloat);
57
58 case lldb::eFormatHex:
59 case lldb::eFormatHexUppercase:
60 case lldb::eFormatOctal:
61 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeInt);
62
63 case lldb::eFormatHexFloat:
64 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeFloat);
65
66 case lldb::eFormatUnicode16:
67 case lldb::eFormatUnicode32:
68
69 case lldb::eFormatUnsigned:
70 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeUnsignedInt);
71
72 case lldb::eFormatVectorOfChar:
73 return type_system->GetBasicTypeFromAST(lldb::eBasicTypeChar);
74
75 case lldb::eFormatVectorOfFloat32:
76 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingIEEE754,
77 32);
78
79 case lldb::eFormatVectorOfFloat64:
80 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingIEEE754,
81 64);
82
83 case lldb::eFormatVectorOfSInt16:
84 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 16);
85
86 case lldb::eFormatVectorOfSInt32:
87 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 32);
88
89 case lldb::eFormatVectorOfSInt64:
90 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 64);
91
92 case lldb::eFormatVectorOfSInt8:
93 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingSint, 8);
94
95 case lldb::eFormatVectorOfUInt128:
96 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 128);
97
98 case lldb::eFormatVectorOfUInt16:
99 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 16);
100
101 case lldb::eFormatVectorOfUInt32:
102 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 32);
103
104 case lldb::eFormatVectorOfUInt64:
105 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 64);
106
107 case lldb::eFormatVectorOfUInt8:
108 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 8);
109
110 case lldb::eFormatDefault:
111 return element_type;
112
113 case lldb::eFormatBinary:
114 case lldb::eFormatComplexInteger:
115 case lldb::eFormatDecimal:
116 case lldb::eFormatEnum:
117 case lldb::eFormatInstruction:
118 case lldb::eFormatOSType:
119 case lldb::eFormatVoid:
120 default:
121 return type_system->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 8);
122 }
123}
124
125static lldb::Format GetItemFormatForFormat(lldb::Format format,
126 CompilerType element_type) {
127 switch (format) {
128 case lldb::eFormatVectorOfChar:
129 return lldb::eFormatChar;
130
131 case lldb::eFormatVectorOfFloat32:
132 case lldb::eFormatVectorOfFloat64:
133 return lldb::eFormatFloat;
134
135 case lldb::eFormatVectorOfSInt16:
136 case lldb::eFormatVectorOfSInt32:
137 case lldb::eFormatVectorOfSInt64:
138 case lldb::eFormatVectorOfSInt8:
139 return lldb::eFormatDecimal;
140
141 case lldb::eFormatVectorOfUInt128:
142 case lldb::eFormatVectorOfUInt16:
143 case lldb::eFormatVectorOfUInt32:
144 case lldb::eFormatVectorOfUInt64:
145 case lldb::eFormatVectorOfUInt8:
146 return lldb::eFormatUnsigned;
147
148 case lldb::eFormatBinary:
149 case lldb::eFormatComplexInteger:
150 case lldb::eFormatDecimal:
151 case lldb::eFormatEnum:
152 case lldb::eFormatInstruction:
153 case lldb::eFormatOSType:
154 case lldb::eFormatVoid:
155 return eFormatHex;
156
157 case lldb::eFormatDefault: {
158 // special case the (default, char) combination to actually display as an
159 // integer value most often, you won't want to see the ASCII characters...
160 // (and if you do, eFormatChar is a keystroke away)
161 bool is_char = element_type.IsCharType();
162 bool is_signed = false;
163 element_type.IsIntegerType(is_signed);
164 return is_char ? (is_signed ? lldb::eFormatDecimal : eFormatHex) : format;
165 } break;
166
167 default:
168 return format;
169 }
170}
171
172static size_t CalculateNumChildren(
173 CompilerType container_type, CompilerType element_type,
174 lldb_private::ExecutionContextScope *exe_scope =
175 nullptr // does not matter here because all we trade in are basic types
176 ) {
177 std::optional<uint64_t> container_size =
178 container_type.GetByteSize(exe_scope);
179 std::optional<uint64_t> element_size = element_type.GetByteSize(exe_scope);
180
181 if (container_size && element_size && *element_size) {
182 if (*container_size % *element_size)
183 return 0;
184 return *container_size / *element_size;
185 }
186 return 0;
187}
188
189namespace lldb_private {
190namespace formatters {
191
192class VectorTypeSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
193public:
194 VectorTypeSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
195 : SyntheticChildrenFrontEnd(*valobj_sp), m_child_type() {}
196
197 ~VectorTypeSyntheticFrontEnd() override = default;
198
199 size_t CalculateNumChildren() override { return m_num_children; }
200
201 lldb::ValueObjectSP GetChildAtIndex(size_t idx) override {
202 if (idx >= CalculateNumChildren())
203 return {};
204 std::optional<uint64_t> size = m_child_type.GetByteSize(nullptr);
205 if (!size)
206 return {};
207 auto offset = idx * *size;
208 StreamString idx_name;
209 idx_name.Printf("[%" PRIu64"l" "u" "]", (uint64_t)idx);
210 ValueObjectSP child_sp(m_backend.GetSyntheticChildAtOffset(
211 offset, m_child_type, true, ConstString(idx_name.GetString())));
212 if (!child_sp)
213 return child_sp;
214
215 child_sp->SetFormat(m_item_format);
216
217 return child_sp;
218 }
219
220 bool Update() override {
221 m_parent_format = m_backend.GetFormat();
222 CompilerType parent_type(m_backend.GetCompilerType());
223 CompilerType element_type;
224 parent_type.IsVectorType(&element_type);
225 m_child_type = ::GetCompilerTypeForFormat(
226 m_parent_format, element_type,
227 parent_type.GetTypeSystem().GetSharedPointer());
228 m_num_children = ::CalculateNumChildren(parent_type, m_child_type);
229 m_item_format = GetItemFormatForFormat(m_parent_format, m_child_type);
230 return false;
231 }
232
233 bool MightHaveChildren() override { return true; }
234
235 size_t GetIndexOfChildWithName(ConstString name) override {
236 const char *item_name = name.GetCString();
237 uint32_t idx = ExtractIndexFromString(item_name);
238 if (idx < UINT32_MAX(4294967295U) && idx >= CalculateNumChildren())
239 return UINT32_MAX(4294967295U);
240 return idx;
241 }
242
243private:
244 lldb::Format m_parent_format = eFormatInvalid;
245 lldb::Format m_item_format = eFormatInvalid;
246 CompilerType m_child_type;
247 size_t m_num_children = 0;
248};
249
250} // namespace formatters
251} // namespace lldb_private
252
253bool lldb_private::formatters::VectorTypeSummaryProvider(
254 ValueObject &valobj, Stream &s, const TypeSummaryOptions &) {
255 auto synthetic_children =
256 VectorTypeSyntheticFrontEndCreator(nullptr, valobj.GetSP());
1
Calling 'VectorTypeSyntheticFrontEndCreator'
→
4
←
Returned allocated memory
→
257 if (!synthetic_children
4.1
'synthetic_children' is non-null
)
5
←
Taking false branch
→
258 return false;
259
260 synthetic_children->Update();
261
262 s.PutChar('(');
263 bool first = true;
264
265 size_t idx = 0, len = synthetic_children->CalculateNumChildren();
266
267 for (; idx < len; idx++) {
6
←
Loop condition is false. Execution continues on line 285
→
268 auto child_sp = synthetic_children->GetChildAtIndex(idx);
269 if (!child_sp)
270 continue;
271 child_sp = child_sp->GetQualifiedRepresentationIfAvailable(
272 lldb::eDynamicDontRunTarget, true);
273
274 const char *child_value = child_sp->GetValueAsCString();
275 if (child_value && *child_value) {
276 if (first) {
277 s.Printf("%s", child_value);
278 first = false;
279 } else {
280 s.Printf(", %s", child_value);
281 }
282 }
283 }
284
285 s.PutChar(')');
7
←
Potential leak of memory pointed to by 'synthetic_children'
286
287 return true;
288}
289
290lldb_private::SyntheticChildrenFrontEnd *
291lldb_private::formatters::VectorTypeSyntheticFrontEndCreator(
292 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
293 if (!valobj_sp)
2
←
Taking false branch
→
294 return nullptr;
295 return new VectorTypeSyntheticFrontEnd(valobj_sp);
3
←
Memory is allocated
→
296}