[llvm-readobj][ELF] Show MIPS GOT content when there is another zero-sized section at the same address
It is possible to have .got section and one or more zero-sized section
at the same address. This patch first checks that GOT (or GOT PLT)
section should have non-zero size using corresponding dynamic tags. Then
it looks up not empty section at the specified address.
Differential Revision: http://reviews.llvm.org/D16968
llvm-svn: 260245
diff --git a/llvm/tools/llvm-readobj/ELFDumper.cpp b/llvm/tools/llvm-readobj/ELFDumper.cpp
index 386d542..14ab4b1 100644
--- a/llvm/tools/llvm-readobj/ELFDumper.cpp
+++ b/llvm/tools/llvm-readobj/ELFDumper.cpp
@@ -497,10 +497,10 @@
}
template <class ELFO>
-static const typename ELFO::Elf_Shdr *findSectionByAddress(const ELFO *Obj,
- uint64_t Addr) {
+static const typename ELFO::Elf_Shdr *
+findNotEmptySectionByAddress(const ELFO *Obj, uint64_t Addr) {
for (const auto &Shdr : Obj->sections())
- if (Shdr.sh_addr == Addr)
+ if (Shdr.sh_addr == Addr && Shdr.sh_size > 0)
return &Shdr;
return nullptr;
}
@@ -1865,23 +1865,6 @@
return;
}
- const Elf_Shdr *GOTShdr = findSectionByAddress(Obj, *DtPltGot);
- if (!GOTShdr) {
- W.startLine() << "There is no .got section in the file.\n";
- return;
- }
-
- ErrorOr<ArrayRef<uint8_t>> GOT = Obj->getSectionContents(GOTShdr);
- if (!GOT) {
- W.startLine() << "The .got section is empty.\n";
- return;
- }
-
- if (*DtLocalGotNum > getGOTTotal(*GOT)) {
- W.startLine() << "MIPS_LOCAL_GOTNO exceeds a number of GOT entries.\n";
- return;
- }
-
const Elf_Shdr *DynSymSec = Dumper->getDotDynSymSec();
ErrorOr<StringRef> StrTable = Obj->getStringTableForSymtab(*DynSymSec);
error(StrTable.getError());
@@ -1889,18 +1872,26 @@
const Elf_Sym *DynSymEnd = Obj->symbol_end(DynSymSec);
std::size_t DynSymTotal = std::size_t(std::distance(DynSymBegin, DynSymEnd));
- if (*DtGotSym > DynSymTotal) {
- W.startLine() << "MIPS_GOTSYM exceeds a number of dynamic symbols.\n";
- return;
- }
+ if (*DtGotSym > DynSymTotal)
+ report_fatal_error("MIPS_GOTSYM exceeds a number of dynamic symbols");
std::size_t GlobalGotNum = DynSymTotal - *DtGotSym;
- if (*DtLocalGotNum + GlobalGotNum > getGOTTotal(*GOT)) {
- W.startLine() << "Number of global GOT entries exceeds the size of GOT.\n";
+ if (*DtLocalGotNum + GlobalGotNum == 0) {
+ W.startLine() << "GOT is empty.\n";
return;
}
+ const Elf_Shdr *GOTShdr = findNotEmptySectionByAddress(Obj, *DtPltGot);
+ if (!GOTShdr)
+ report_fatal_error("There is no not empty GOT section at 0x" +
+ Twine::utohexstr(*DtPltGot));
+
+ ErrorOr<ArrayRef<uint8_t>> GOT = Obj->getSectionContents(GOTShdr);
+
+ if (*DtLocalGotNum + GlobalGotNum > getGOTTotal(*GOT))
+ report_fatal_error("Number of GOT entries exceeds the size of GOT section");
+
const GOTEntry *GotBegin = makeGOTIter(*GOT, 0);
const GOTEntry *GotLocalEnd = makeGOTIter(*GOT, *DtLocalGotNum);
const GOTEntry *It = GotBegin;
@@ -1957,22 +1948,16 @@
return;
}
- const Elf_Shdr *PLTShdr = findSectionByAddress(Obj, *DtMipsPltGot);
- if (!PLTShdr) {
- W.startLine() << "There is no .got.plt section in the file.\n";
- return;
- }
+ const Elf_Shdr *PLTShdr = findNotEmptySectionByAddress(Obj, *DtMipsPltGot);
+ if (!PLTShdr)
+ report_fatal_error("There is no not empty PLTGOT section at 0x " +
+ Twine::utohexstr(*DtMipsPltGot));
ErrorOr<ArrayRef<uint8_t>> PLT = Obj->getSectionContents(PLTShdr);
- if (!PLT) {
- W.startLine() << "The .got.plt section is empty.\n";
- return;
- }
- const Elf_Shdr *PLTRelShdr = findSectionByAddress(Obj, *DtJmpRel);
- if (!PLTShdr) {
- W.startLine() << "There is no .rel.plt section in the file.\n";
- return;
- }
+ const Elf_Shdr *PLTRelShdr = findNotEmptySectionByAddress(Obj, *DtJmpRel);
+ if (!PLTRelShdr)
+ report_fatal_error("There is no not empty RELPLT section at 0x" +
+ Twine::utohexstr(*DtJmpRel));
ErrorOr<const Elf_Shdr *> SymTableOrErr =
Obj->getSection(PLTRelShdr->sh_link);
error(SymTableOrErr.getError());