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Diffstat (limited to 'include/llvm/Object/ELF.h')
-rw-r--r--include/llvm/Object/ELF.h112
1 files changed, 63 insertions, 49 deletions
diff --git a/include/llvm/Object/ELF.h b/include/llvm/Object/ELF.h
index cf8e4529bad9..28b00c8413de 100644
--- a/include/llvm/Object/ELF.h
+++ b/include/llvm/Object/ELF.h
@@ -64,6 +64,10 @@ std::string getSecIndexForError(const ELFFile<ELFT> *Obj,
return "[unknown index]";
}
+static inline Error defaultWarningHandler(const Twine &Msg) {
+ return createError(Msg);
+}
+
template <class ELFT>
class ELFFile {
public:
@@ -95,6 +99,13 @@ public:
using Elf_Relr_Range = typename ELFT::RelrRange;
using Elf_Phdr_Range = typename ELFT::PhdrRange;
+ // This is a callback that can be passed to a number of functions.
+ // It can be used to ignore non-critical errors (warnings), which is
+ // useful for dumpers, like llvm-readobj.
+ // It accepts a warning message string and returns a success
+ // when the warning should be ignored or an error otherwise.
+ using WarningHandler = llvm::function_ref<Error(const Twine &Msg)>;
+
const uint8_t *base() const { return Buf.bytes_begin(); }
size_t getBufSize() const { return Buf.size(); }
@@ -114,7 +125,9 @@ public:
template <typename T>
Expected<const T *> getEntry(const Elf_Shdr *Section, uint32_t Entry) const;
- Expected<StringRef> getStringTable(const Elf_Shdr *Section) const;
+ Expected<StringRef>
+ getStringTable(const Elf_Shdr *Section,
+ WarningHandler WarnHandler = &defaultWarningHandler) const;
Expected<StringRef> getStringTableForSymtab(const Elf_Shdr &Section) const;
Expected<StringRef> getStringTableForSymtab(const Elf_Shdr &Section,
Elf_Shdr_Range Sections) const;
@@ -137,15 +150,16 @@ public:
static Expected<ELFFile> create(StringRef Object);
+ bool isLE() const {
+ return getHeader()->getDataEncoding() == ELF::ELFDATA2LSB;
+ }
+
bool isMipsELF64() const {
return getHeader()->e_machine == ELF::EM_MIPS &&
getHeader()->getFileClass() == ELF::ELFCLASS64;
}
- bool isMips64EL() const {
- return isMipsELF64() &&
- getHeader()->getDataEncoding() == ELF::ELFDATA2LSB;
- }
+ bool isMips64EL() const { return isMipsELF64() && isLE(); }
Expected<Elf_Shdr_Range> sections() const;
@@ -261,7 +275,9 @@ public:
return make_range(notes_begin(Shdr, Err), notes_end());
}
- Expected<StringRef> getSectionStringTable(Elf_Shdr_Range Sections) const;
+ Expected<StringRef> getSectionStringTable(
+ Elf_Shdr_Range Sections,
+ WarningHandler WarnHandler = &defaultWarningHandler) const;
Expected<uint32_t> getSectionIndex(const Elf_Sym *Sym, Elf_Sym_Range Syms,
ArrayRef<Elf_Word> ShndxTable) const;
Expected<const Elf_Shdr *> getSection(const Elf_Sym *Sym,
@@ -271,12 +287,13 @@ public:
Elf_Sym_Range Symtab,
ArrayRef<Elf_Word> ShndxTable) const;
Expected<const Elf_Shdr *> getSection(uint32_t Index) const;
- Expected<const Elf_Shdr *> getSection(const StringRef SectionName) const;
Expected<const Elf_Sym *> getSymbol(const Elf_Shdr *Sec,
uint32_t Index) const;
- Expected<StringRef> getSectionName(const Elf_Shdr *Section) const;
+ Expected<StringRef>
+ getSectionName(const Elf_Shdr *Section,
+ WarningHandler WarnHandler = &defaultWarningHandler) const;
Expected<StringRef> getSectionName(const Elf_Shdr *Section,
StringRef DotShstrtab) const;
template <typename T>
@@ -459,18 +476,18 @@ ELFFile<ELFT>::getRelocationSymbol(const Elf_Rel *Rel,
template <class ELFT>
Expected<StringRef>
-ELFFile<ELFT>::getSectionStringTable(Elf_Shdr_Range Sections) const {
+ELFFile<ELFT>::getSectionStringTable(Elf_Shdr_Range Sections,
+ WarningHandler WarnHandler) const {
uint32_t Index = getHeader()->e_shstrndx;
if (Index == ELF::SHN_XINDEX)
Index = Sections[0].sh_link;
if (!Index) // no section string table.
return "";
- // TODO: Test a case when the sh_link of the section with index 0 is broken.
if (Index >= Sections.size())
return createError("section header string table index " + Twine(Index) +
" does not exist");
- return getStringTable(&Sections[Index]);
+ return getStringTable(&Sections[Index], WarnHandler);
}
template <class ELFT> ELFFile<ELFT>::ELFFile(StringRef Object) : Buf(Object) {}
@@ -495,7 +512,8 @@ Expected<typename ELFT::ShdrRange> ELFFile<ELFT>::sections() const {
Twine(getHeader()->e_shentsize));
const uint64_t FileSize = Buf.size();
- if (SectionTableOffset + sizeof(Elf_Shdr) > FileSize)
+ if (SectionTableOffset + sizeof(Elf_Shdr) > FileSize ||
+ SectionTableOffset + (uintX_t)sizeof(Elf_Shdr) < SectionTableOffset)
return createError(
"section header table goes past the end of the file: e_shoff = 0x" +
Twine::utohexstr(SectionTableOffset));
@@ -513,15 +531,22 @@ Expected<typename ELFT::ShdrRange> ELFFile<ELFT>::sections() const {
NumSections = First->sh_size;
if (NumSections > UINT64_MAX / sizeof(Elf_Shdr))
- // TODO: this error is untested.
- return createError("section table goes past the end of file");
+ return createError("invalid number of sections specified in the NULL "
+ "section's sh_size field (" +
+ Twine(NumSections) + ")");
const uint64_t SectionTableSize = NumSections * sizeof(Elf_Shdr);
+ if (SectionTableOffset + SectionTableSize < SectionTableOffset)
+ return createError(
+ "invalid section header table offset (e_shoff = 0x" +
+ Twine::utohexstr(SectionTableOffset) +
+ ") or invalid number of sections specified in the first section "
+ "header's sh_size field (0x" +
+ Twine::utohexstr(NumSections) + ")");
// Section table goes past end of file!
if (SectionTableOffset + SectionTableSize > FileSize)
return createError("section table goes past the end of file");
-
return makeArrayRef(First, NumSections);
}
@@ -540,8 +565,9 @@ template <typename T>
Expected<const T *> ELFFile<ELFT>::getEntry(const Elf_Shdr *Section,
uint32_t Entry) const {
if (sizeof(T) != Section->sh_entsize)
- // TODO: this error is untested.
- return createError("invalid sh_entsize");
+ return createError("section " + getSecIndexForError(this, Section) +
+ " has invalid sh_entsize: expected " + Twine(sizeof(T)) +
+ ", but got " + Twine(Section->sh_entsize));
size_t Pos = Section->sh_offset + Entry * sizeof(T);
if (Pos + sizeof(T) > Buf.size())
return createError("unable to access section " +
@@ -561,42 +587,26 @@ ELFFile<ELFT>::getSection(uint32_t Index) const {
}
template <class ELFT>
-Expected<const typename ELFT::Shdr *>
-ELFFile<ELFT>::getSection(const StringRef SectionName) const {
- auto TableOrErr = sections();
- if (!TableOrErr)
- return TableOrErr.takeError();
- for (auto &Sec : *TableOrErr) {
- auto SecNameOrErr = getSectionName(&Sec);
- if (!SecNameOrErr)
- return SecNameOrErr.takeError();
- if (*SecNameOrErr == SectionName)
- return &Sec;
- }
- // TODO: this error is untested.
- return createError("invalid section name");
-}
-
-template <class ELFT>
Expected<StringRef>
-ELFFile<ELFT>::getStringTable(const Elf_Shdr *Section) const {
+ELFFile<ELFT>::getStringTable(const Elf_Shdr *Section,
+ WarningHandler WarnHandler) const {
if (Section->sh_type != ELF::SHT_STRTAB)
- return createError("invalid sh_type for string table section " +
- getSecIndexForError(this, Section) +
- ": expected SHT_STRTAB, but got " +
- object::getELFSectionTypeName(getHeader()->e_machine,
- Section->sh_type));
+ if (Error E = WarnHandler("invalid sh_type for string table section " +
+ getSecIndexForError(this, Section) +
+ ": expected SHT_STRTAB, but got " +
+ object::getELFSectionTypeName(
+ getHeader()->e_machine, Section->sh_type)))
+ return std::move(E);
+
auto V = getSectionContentsAsArray<char>(Section);
if (!V)
return V.takeError();
ArrayRef<char> Data = *V;
if (Data.empty())
- // TODO: this error is untested.
- return createError("empty string table");
+ return createError("SHT_STRTAB string table section " +
+ getSecIndexForError(this, Section) + " is empty");
if (Data.back() != '\0')
- return createError(object::getELFSectionTypeName(getHeader()->e_machine,
- Section->sh_type) +
- " string table section " +
+ return createError("SHT_STRTAB string table section " +
getSecIndexForError(this, Section) +
" is non-null terminated");
return StringRef(Data.begin(), Data.size());
@@ -626,8 +636,11 @@ ELFFile<ELFT>::getSHNDXTable(const Elf_Shdr &Section,
const Elf_Shdr &SymTable = **SymTableOrErr;
if (SymTable.sh_type != ELF::SHT_SYMTAB &&
SymTable.sh_type != ELF::SHT_DYNSYM)
- // TODO: this error is untested.
- return createError("invalid sh_type");
+ return createError("SHT_SYMTAB_SHNDX section is linked with " +
+ object::getELFSectionTypeName(getHeader()->e_machine,
+ SymTable.sh_type) +
+ " section (expected SHT_SYMTAB/SHT_DYNSYM)");
+
if (V.size() != (SymTable.sh_size / sizeof(Elf_Sym)))
return createError("SHT_SYMTAB_SHNDX section has sh_size (" +
Twine(SymTable.sh_size) +
@@ -662,11 +675,12 @@ ELFFile<ELFT>::getStringTableForSymtab(const Elf_Shdr &Sec,
template <class ELFT>
Expected<StringRef>
-ELFFile<ELFT>::getSectionName(const Elf_Shdr *Section) const {
+ELFFile<ELFT>::getSectionName(const Elf_Shdr *Section,
+ WarningHandler WarnHandler) const {
auto SectionsOrErr = sections();
if (!SectionsOrErr)
return SectionsOrErr.takeError();
- auto Table = getSectionStringTable(*SectionsOrErr);
+ auto Table = getSectionStringTable(*SectionsOrErr, WarnHandler);
if (!Table)
return Table.takeError();
return getSectionName(Section, *Table);
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-02 04:29:34 +0000