Assorted bugfixes in object file handling:
- Adds support for sniffing PE/COFF files on win32 (.exe and .dll)
which are COFF files that have an MS-DOS compatibility stub on
the front of them.
- Fixes a bug in the COFFObjectFile's support for the Microsoft COFF
extension for long symbol names, wherein it was attempting to parse
the leading '/' in an extended symbol name reference as part of the
integer offset.
- Fixes bugs in COFFObjectFile and ELFObjectFile wherein section
and symbol iterators were being returned with uninitialized bytes;
the type DataRefImpl is a union between 2 32-bit words (d.a and d.b)
and a single intptr_t word (p). Only p was being initialized, so in
32-bit builds the result would be iterators with random upper 32-bit
words in their DataRefImpls. This caused random failures when
seeking around in object files.
Patch by Graydon Hoare!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128799 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Object/COFFObjectFile.cpp b/lib/Object/COFFObjectFile.cpp
index cfee82a..30709f1 100644
--- a/lib/Object/COFFObjectFile.cpp
+++ b/lib/Object/COFFObjectFile.cpp
@@ -91,6 +91,7 @@
namespace {
class COFFObjectFile : public ObjectFile {
private:
+ uint64_t HeaderOff;
const coff_file_header *Header;
const coff_section *SectionTable;
const coff_symbol *SymbolTable;
@@ -256,7 +257,7 @@
// Check for string table entry. First byte is '/'.
if (name[0] == '/') {
uint32_t Offset;
- name.getAsInteger(10, Offset);
+ name.substr(1).getAsInteger(10, Offset);
return StringRef(getString(Offset));
}
@@ -287,9 +288,20 @@
COFFObjectFile::COFFObjectFile(MemoryBuffer *Object)
: ObjectFile(Object) {
- Header = reinterpret_cast<const coff_file_header *>(base);
+
+ HeaderOff = 0;
+
+ if (base[0] == 0x4d && base[1] == 0x5a) {
+ // PE/COFF, seek through MS-DOS compatibility stub and 4-byte
+ // PE signature to find 'normal' COFF header.
+ HeaderOff += *reinterpret_cast<const ulittle32_t *>(base + 0x3c);
+ HeaderOff += 4;
+ }
+
+ Header = reinterpret_cast<const coff_file_header *>(base + HeaderOff);
SectionTable =
reinterpret_cast<const coff_section *>( base
+ + HeaderOff
+ sizeof(coff_file_header)
+ Header->SizeOfOptionalHeader);
SymbolTable =
@@ -303,6 +315,7 @@
ObjectFile::symbol_iterator COFFObjectFile::begin_symbols() const {
DataRefImpl ret;
+ memset(&ret, 0, sizeof(DataRefImpl));
ret.p = reinterpret_cast<intptr_t>(SymbolTable);
return symbol_iterator(SymbolRef(ret, this));
}
@@ -310,18 +323,21 @@
ObjectFile::symbol_iterator COFFObjectFile::end_symbols() const {
// The symbol table ends where the string table begins.
DataRefImpl ret;
+ memset(&ret, 0, sizeof(DataRefImpl));
ret.p = reinterpret_cast<intptr_t>(StringTable);
return symbol_iterator(SymbolRef(ret, this));
}
ObjectFile::section_iterator COFFObjectFile::begin_sections() const {
DataRefImpl ret;
+ memset(&ret, 0, sizeof(DataRefImpl));
ret.p = reinterpret_cast<intptr_t>(SectionTable);
return section_iterator(SectionRef(ret, this));
}
ObjectFile::section_iterator COFFObjectFile::end_sections() const {
DataRefImpl ret;
+ memset(&ret, 0, sizeof(DataRefImpl));
ret.p = reinterpret_cast<intptr_t>(SectionTable + Header->NumberOfSections);
return section_iterator(SectionRef(ret, this));
}