[lld] r283426 - [ELF] - Make checks in ObjectFile<ELFT>::getSection() stricter.

[George Rimar via llvm-commits]

Author: grimar
Date: Thu Oct  6 04:17:55 2016
New Revision: 283426

URL: http://llvm.org/viewvc/llvm-project?rev=283426&view=rev
Log:
[ELF] - Make checks in ObjectFile<ELFT>::getSection() stricter.

This patch makes the check for null section stricter, 
so it is only allowed for STT_SECTION symbols now.

Differential revision: https://reviews.llvm.org/D25231

Added:
    lld/trunk/test/ELF/invalid/Inputs/section-index2.elf   (with props)
Modified:
    lld/trunk/ELF/InputFiles.cpp
    lld/trunk/test/ELF/invalid/invalid-elf.test

Modified: lld/trunk/ELF/InputFiles.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputFiles.cpp?rev=283426&r1=283425&r2=283426&view=diff
==============================================================================
--- lld/trunk/ELF/InputFiles.cpp (original)
+++ lld/trunk/ELF/InputFiles.cpp Thu Oct  6 04:17:55 2016
@@ -377,17 +377,22 @@ template <class ELFT>
 InputSectionBase<ELFT> *
 elf::ObjectFile<ELFT>::getSection(const Elf_Sym &Sym) const {
   uint32_t Index = this->getSectionIndex(Sym);
-  if (Index == 0)
-    return nullptr;
   if (Index >= Sections.size())
     fatal(getFilename(this) + ": invalid section index: " + Twine(Index));
   InputSectionBase<ELFT> *S = Sections[Index];
+
   // We found that GNU assembler 2.17.50 [FreeBSD] 2007-07-03
   // could generate broken objects. STT_SECTION symbols can be
   // associated with SHT_REL[A]/SHT_SYMTAB/SHT_STRTAB sections.
   // In this case it is fine for section to be null here as we
   // do not allocate sections of these types.
-  if (!S || S == &InputSectionBase<ELFT>::Discarded)
+  if (!S) {
+    if (Index == 0 || Sym.getType() == STT_SECTION)
+      return nullptr;
+    fatal(getFilename(this) + ": invalid section index: " + Twine(Index));
+  }
+
+  if (S == &InputSectionBase<ELFT>::Discarded)
     return S;
   return S->Repl;
 }

Added: lld/trunk/test/ELF/invalid/Inputs/section-index2.elf
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/invalid/Inputs/section-index2.elf?rev=283426&view=auto
==============================================================================
Binary file - no diff available.

Propchange: lld/trunk/test/ELF/invalid/Inputs/section-index2.elf
------------------------------------------------------------------------------
    svn:mime-type = application/octet-stream

Modified: lld/trunk/test/ELF/invalid/invalid-elf.test
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/invalid/invalid-elf.test?rev=283426&r1=283425&r2=283426&view=diff
==============================================================================
--- lld/trunk/test/ELF/invalid/invalid-elf.test (original)
+++ lld/trunk/test/ELF/invalid/invalid-elf.test Thu Oct  6 04:17:55 2016
@@ -20,6 +20,10 @@
 # RUN:   FileCheck --check-prefix=INVALID-SECTION-INDEX-LLD %s
 # INVALID-SECTION-INDEX-LLD: invalid section index
 
+## section-index2.elf has local symbol with incorrect section index.
+# RUN: not ld.lld %p/Inputs/section-index2.elf -o %t2 2>&1 | \
+# RUN:   FileCheck --check-prefix=INVALID-SECTION-INDEX-LLD %s
+
 # RUN: not ld.lld %p/Inputs/shstrndx.so -o %t2 2>&1 | \
 # RUN:   FileCheck --check-prefix=INVALID-SECTION-INDEX %s
 # INVALID-SECTION-INDEX: Invalid section index