[test/Object][llvm-objdump] - llvm-objdump: don't abort() when the e_phoff field is invalid and refine testing.

[grimar]

Summary

llvm-objdump currently calls report_fatal_error() when the e_phoff field is invalid.

This is tested by elf-invalid-phdr.test which has the following issues:

1. It uses a precompiled object.
2. it could be a part of invalid.test.
3. It tests the Object lib, but we have no separate test for llvm-objdump.

This patch addresses issues mentioned.

[MaskRay]

Thanks!

[jhenderson]

LGTM too!

llvm/test/Object/elf-invalid-phdr.test

-# invalid-phdr.elf is generated by creating a simple elf file with yaml2obj:
-# !ELF
-# FileHeader:
-#   Class:           ELFCLASS64
-#   Data:            ELFDATA2LSB
-#   Type:            ET_EXEC
-#   Machine:         EM_X86_64
-# Sections:
-#   - Name:            .text
-#     Type:            SHT_PROGBITS
-#     Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
-#     AddressAlign:    0x0000000000001000
-#     Content:         "00000000"
-# ProgramHeaders:
-#   - Type: PT_LOAD
-#     Flags: [ PF_X, PF_R ]
-#     VAddr: 0xAAAA1000
-#     PAddr: 0xFFFF1000
-#     Sections:
-#       - Section: .text
-#
-# Then editing the e_phoff in with a hexeditor to set it to 0xffffff
-RUN: not --crash llvm-objdump --private-headers %p/Inputs/invalid-phdr.elf 2>&1 \
-RUN:         | FileCheck %s
-
-CHECK: LLVM ERROR: program headers are longer than binary of size 4162: e_phoff = 0xffffff, e_phnum = 1, e_phentsize = 56

llvm/test/Object/invalid.test

FileHeader:
   Data:     ELFDATA2LSB
   Type:     ET_REL
   Machine:  EM_X86_64
 ## SHN_XINDEX == 0xffff.
   SHStrNdx: 0xffff
 Sections:
   - Type: SHT_NULL
     Link: 0xff
+
+## Check the case when the e_phoff field is invalid.
+# RUN: yaml2obj --docnum=31 %s -o %t31
+# RUN: not llvm-objdump --private-headers %t31 2>&1 | FileCheck -DFILE=%t31 %s --check-prefix=INVALID-PHOFF
+
+# INVALID-PHOFF: error: '[[FILE]]': program headers are longer than binary of size 280: e_phoff = 0xffffff, e_phnum = 0, e_phentsize = 0
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+  EPhOff:  0xffffff

llvm/test/tools/llvm-objdump/ELF/invalid-phdr.test

+## Test how we handle the case when the e_phoff field is invalid.
+# RUN: yaml2obj %s -o %t
+# RUN: not llvm-objdump --private-headers %t 2>&1 | \
+# RUN:   FileCheck -DFILE=%t %s --check-prefix=INVALID-PHOFF
+
+# INVALID-PHOFF:      Program Header:
+# INVALID-PHOFF-NEXT: warning: '[[FILE]]': unable to read program headers: program headers are longer than binary of size 280: e_phoff = 0xffffff, e_phnum = 0, e_phentsize = 0
+# INVALID-PHOFF-NEXT: error: '[[FILE]]': program headers are longer than binary of size 280: e_phoff = 0xffffff, e_phnum = 0, e_phentsize = 0
+
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_X86_64
+  EPhOff:  0xffffff

llvm/tools/llvm-objdump/ELFDump.cpp

if (Dyn.d_tag == ELF::DT_NEEDED || Dyn.d_tag == ELF::DT_RPATH ||
       }
       reportWarning(toString(StrTabOrErr.takeError()), Filename);
       consumeError(StrTabOrErr.takeError());
     }
     outs() << format(Fmt, (uint64_t)Dyn.d_un.d_val);
   }
 }
 
-template <class ELFT> static void printProgramHeaders(const ELFFile<ELFT> *o) {
+template <class ELFT>
+static void printProgramHeaders(const ELFFile<ELFT> *Obj, StringRef FileName) {
   outs() << "Program Header:\n";
-  auto ProgramHeaderOrError = o->program_headers();
-  if (!ProgramHeaderOrError)
-    report_fatal_error(toString(ProgramHeaderOrError.takeError()));
+  auto ProgramHeaderOrError = Obj->program_headers();
+  if (!ProgramHeaderOrError) {
+    reportWarning("unable to read program headers: " +
+                      toString(ProgramHeaderOrError.takeError()),
+                  FileName);
+    return;
+  }
+
   for (const typename ELFT::Phdr &Phdr : *ProgramHeaderOrError) {
     switch (Phdr.p_type) {
     case ELF::PT_DYNAMIC:
       outs() << " DYNAMIC ";
       break;
     case ELF::PT_GNU_EH_FRAME:
       outs() << "EH_FRAME ";
       break;
if (Shdr.sh_type == ELF::SHT_GNU_verneed)
       printSymbolVersionDependency<ELFT>(Contents, StrTab);
     else
       printSymbolVersionDefinition<ELFT>(Shdr, Contents, StrTab);
   }
 }
 
 void objdump::printELFFileHeader(const object::ObjectFile *Obj) {
   if (const auto *ELFObj = dyn_cast<ELF32LEObjectFile>(Obj))
-    printProgramHeaders(ELFObj->getELFFile());
+    printProgramHeaders(ELFObj->getELFFile(), Obj->getFileName());
   else if (const auto *ELFObj = dyn_cast<ELF32BEObjectFile>(Obj))
-    printProgramHeaders(ELFObj->getELFFile());
+    printProgramHeaders(ELFObj->getELFFile(), Obj->getFileName());
   else if (const auto *ELFObj = dyn_cast<ELF64LEObjectFile>(Obj))
-    printProgramHeaders(ELFObj->getELFFile());
+    printProgramHeaders(ELFObj->getELFFile(), Obj->getFileName());
   else if (const auto *ELFObj = dyn_cast<ELF64BEObjectFile>(Obj))
-    printProgramHeaders(ELFObj->getELFFile());
+    printProgramHeaders(ELFObj->getELFFile(), Obj->getFileName());
 }
 
 void objdump::printELFDynamicSection(const object::ObjectFile *Obj) {
   if (const auto *ELFObj = dyn_cast<ELF32LEObjectFile>(Obj))
     printDynamicSection(ELFObj->getELFFile(), Obj->getFileName());
   else if (const auto *ELFObj = dyn_cast<ELF32BEObjectFile>(Obj))
     printDynamicSection(ELFObj->getELFFile(), Obj->getFileName());
   else if (const auto *ELFObj = dyn_cast<ELF64LEObjectFile>(Obj))