Bug Summary

File:tools/llvm-readobj/ObjDumper.cpp
Warning:line 136, column 70
The left operand of '*' is a garbage value

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ObjDumper.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/llvm-readobj -I /build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-readobj -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/llvm-readobj -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-readobj/ObjDumper.cpp -faddrsig
1//===-- ObjDumper.cpp - Base dumper class -----------------------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9///
10/// \file
11/// This file implements ObjDumper.
12///
13//===----------------------------------------------------------------------===//
14
15#include "ObjDumper.h"
16#include "Error.h"
17#include "llvm-readobj.h"
18#include "llvm/Object/ObjectFile.h"
19#include "llvm/Support/Error.h"
20#include "llvm/Support/ScopedPrinter.h"
21#include "llvm/Support/raw_ostream.h"
22
23namespace llvm {
24
25ObjDumper::ObjDumper(ScopedPrinter &Writer) : W(Writer) {}
26
27ObjDumper::~ObjDumper() {
28}
29
30static void printAsPrintable(raw_ostream &W, const uint8_t *Start, size_t Len) {
31 for (size_t i = 0; i < Len; i++)
32 W << (isPrint(Start[i]) ? static_cast<char>(Start[i]) : '.');
33}
34
35static Expected<object::SectionRef>
36getSecNameOrIndexAsSecRef(const object::ObjectFile *Obj, StringRef SecName) {
37 char *StrPtr;
38 long SectionIndex = strtol(SecName.data(), &StrPtr, 10);
39 object::SectionRef Section;
40 long SecIndex;
41 if (Obj->isELF())
42 SecIndex = 0;
43 else
44 SecIndex = 1;
45 for (object::SectionRef SecRef : Obj->sections()) {
46 if (*StrPtr) {
47 StringRef SectionName;
48
49 if (std::error_code E = SecRef.getName(SectionName))
50 return errorCodeToError(E);
51
52 if (SectionName == SecName)
53 return SecRef;
54 } else if (SecIndex == SectionIndex)
55 return SecRef;
56
57 SecIndex++;
58 }
59 return make_error<StringError>("invalid section reference",
60 object::object_error::parse_failed);
61}
62
63void ObjDumper::printSectionAsString(const object::ObjectFile *Obj,
64 StringRef SecName) {
65 Expected<object::SectionRef> SectionRefOrError =
66 getSecNameOrIndexAsSecRef(Obj, SecName);
67 if (!SectionRefOrError)
68 error(std::move(SectionRefOrError));
69 object::SectionRef Section = *SectionRefOrError;
70 StringRef SectionName;
71
72 if (std::error_code E = Section.getName(SectionName))
73 error(E);
74 W.startLine() << "String dump of section '" << SectionName << "':\n";
75
76 StringRef SectionContent;
77 Section.getContents(SectionContent);
78
79 const uint8_t *SecContent = SectionContent.bytes_begin();
80 const uint8_t *CurrentWord = SecContent;
81 const uint8_t *SecEnd = SectionContent.bytes_end();
82
83 while (CurrentWord <= SecEnd) {
84 size_t WordSize = strnlen(reinterpret_cast<const char *>(CurrentWord),
85 SecEnd - CurrentWord);
86 if (!WordSize) {
87 CurrentWord++;
88 continue;
89 }
90 W.startLine() << format("[%6tx] ", CurrentWord - SecContent);
91 printAsPrintable(W.startLine(), CurrentWord, WordSize);
92 W.startLine() << '\n';
93 CurrentWord += WordSize + 1;
94 }
95}
96
97void ObjDumper::printSectionAsHex(const object::ObjectFile *Obj,
98 StringRef SecName) {
99 Expected<object::SectionRef> SectionRefOrError =
100 getSecNameOrIndexAsSecRef(Obj, SecName);
101 if (!SectionRefOrError)
1
Taking false branch
102 error(std::move(SectionRefOrError));
103 object::SectionRef Section = *SectionRefOrError;
104 StringRef SectionName;
105
106 if (std::error_code E = Section.getName(SectionName))
2
Taking false branch
107 error(E);
108 W.startLine() << "Hex dump of section '" << SectionName << "':\n";
109
110 StringRef SectionContent;
111 Section.getContents(SectionContent);
112 const uint8_t *SecContent = SectionContent.bytes_begin();
113 const uint8_t *SecEnd = SecContent + SectionContent.size();
114
115 for (const uint8_t *SecPtr = SecContent; SecPtr < SecEnd; SecPtr += 16) {
3
Loop condition is true. Entering loop body
116 const uint8_t *TmpSecPtr = SecPtr;
117 uint8_t i;
118 uint8_t k;
4
'k' declared without an initial value
119
120 W.startLine() << format_hex(SecPtr - SecContent, 10);
121 W.startLine() << ' ';
122 for (i = 0; TmpSecPtr < SecEnd && i < 4; ++i) {
123 for (k = 0; TmpSecPtr < SecEnd && k < 4; k++, TmpSecPtr++) {
124 uint8_t Val = *(reinterpret_cast<const uint8_t *>(TmpSecPtr));
125 W.startLine() << format_hex_no_prefix(Val, 2);
126 }
127 W.startLine() << ' ';
128 }
129
130 // We need to print the correct amount of spaces to match the format.
131 // We are adding the (4 - i) last rows that are 8 characters each.
132 // Then, the (4 - i) spaces that are in between the rows.
133 // Least, if we cut in a middle of a row, we add the remaining characters,
134 // which is (8 - (k * 2))
135 if (i < 4)
5
Taking true branch
136 W.startLine() << format("%*c", (4 - i) * 8 + (4 - i) + (8 - (k * 2)),
6
The left operand of '*' is a garbage value
137 ' ');
138
139 TmpSecPtr = SecPtr;
140 for (i = 0; TmpSecPtr + i < SecEnd && i < 16; ++i)
141 W.startLine() << (isPrint(TmpSecPtr[i]) ? static_cast<char>(TmpSecPtr[i])
142 : '.');
143
144 W.startLine() << '\n';
145 }
146}
147
148} // namespace llvm