[llvm] r239124 - [Object, ELF] Fix segmentation fault in ELFFile::getSectionName().

[Alexey Samsonov]

Author: samsonov
Date: Thu Jun  4 18:40:23 2015
New Revision: 239124

URL: http://llvm.org/viewvc/llvm-project?rev=239124&view=rev
Log:
[Object, ELF] Fix segmentation fault in ELFFile::getSectionName().

Don't do a null dereference if .shstrtab section is missing.

Added:
    llvm/trunk/test/DebugInfo/Inputs/invalid.elf.no-shstrtab
Modified:
    llvm/trunk/include/llvm/Object/ELF.h
    llvm/trunk/test/DebugInfo/dwarfdump-invalid.test

Modified: llvm/trunk/include/llvm/Object/ELF.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/ELF.h?rev=239124&r1=239123&r2=239124&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/ELF.h (original)
+++ llvm/trunk/include/llvm/Object/ELF.h Thu Jun  4 18:40:23 2015
@@ -928,7 +928,7 @@ ErrorOr<StringRef> ELFFile<ELFT>::getSym
 template <class ELFT>
 ErrorOr<StringRef>
 ELFFile<ELFT>::getSectionName(const Elf_Shdr *Section) const {
-  if (Section->sh_name >= dot_shstrtab_sec->sh_size)
+  if (!dot_shstrtab_sec || Section->sh_name >= dot_shstrtab_sec->sh_size)
     return object_error::parse_failed;
   return StringRef(getString(dot_shstrtab_sec, Section->sh_name));
 }

Added: llvm/trunk/test/DebugInfo/Inputs/invalid.elf.no-shstrtab
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/Inputs/invalid.elf.no-shstrtab?rev=239124&view=auto
==============================================================================
Binary files llvm/trunk/test/DebugInfo/Inputs/invalid.elf.no-shstrtab (added) and llvm/trunk/test/DebugInfo/Inputs/invalid.elf.no-shstrtab Thu Jun  4 18:40:23 2015 differ

Modified: llvm/trunk/test/DebugInfo/dwarfdump-invalid.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/dwarfdump-invalid.test?rev=239124&r1=239123&r2=239124&view=diff
==============================================================================
--- llvm/trunk/test/DebugInfo/dwarfdump-invalid.test (original)
+++ llvm/trunk/test/DebugInfo/dwarfdump-invalid.test Thu Jun  4 18:40:23 2015
@@ -4,3 +4,6 @@ RUN: llvm-dwarfdump %p/Inputs/invalid.el
 RUN: llvm-dwarfdump %p/Inputs/invalid.elf.2 2>&1 | FileCheck %s --check-prefix=INVALID-ELF
 RUN: llvm-dwarfdump %p/Inputs/invalid.elf.3 2>&1 | FileCheck %s --check-prefix=INVALID-ELF
 INVALID-ELF: Invalid data was encountered while parsing the file
+
+RUN: llvm-dwarfdump %p/Inputs/invalid.elf.no-shstrtab 2>&1 | FileCheck %s --check-prefix=EMPTY
+EMPTY: .debug_info contents: