[llvm] r268403 - Produce another specific error message for a malformed Mach-O file when a load

[Kevin Enderby via llvm-commits]

Author: enderby
Date: Tue May  3 12:16:08 2016
New Revision: 268403

URL: http://llvm.org/viewvc/llvm-project?rev=268403&view=rev
Log:
Produce another specific error message for a malformed Mach-O file when a load
command other than the first one is past the end of the load commands.

This is like the test case in test/Object/macho-invalid.test for
macho64-invalid-incomplete-load-command but it is the second load command
that is past the end of all the load commands instead of the first.

The code in the constructor for MachOObjectFile that loops over the load
commands used getNextLoadCommandInfo() which was not producing
a good error message.  So that was fixed and a test case was added.

Added:
    llvm/trunk/test/Object/Inputs/macho64-invalid-incomplete-load-command.1   (with props)
Modified:
    llvm/trunk/lib/Object/MachOObjectFile.cpp
    llvm/trunk/test/Object/macho-invalid.test

Modified: llvm/trunk/lib/Object/MachOObjectFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/MachOObjectFile.cpp?rev=268403&r1=268402&r2=268403&view=diff
==============================================================================
--- llvm/trunk/lib/Object/MachOObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/MachOObjectFile.cpp Tue May  3 12:16:08 2016
@@ -199,8 +199,16 @@ getFirstLoadCommandInfo(const MachOObjec
 }
 
 static Expected<MachOObjectFile::LoadCommandInfo>
-getNextLoadCommandInfo(const MachOObjectFile *Obj,
+getNextLoadCommandInfo(const MachOObjectFile *Obj, uint32_t LoadCommandIndex,
                        const MachOObjectFile::LoadCommandInfo &L) {
+  unsigned HeaderSize = Obj->is64Bit() ? sizeof(MachO::mach_header_64)
+                                       : sizeof(MachO::mach_header);
+  if (L.Ptr + L.C.cmdsize + sizeof(MachOObjectFile::LoadCommandInfo) >
+      Obj->getData().data() + HeaderSize + Obj->getHeader().sizeofcmds)
+    return malformedError(*Obj, Twine("truncated or malformed object "
+                          "(load command ") + Twine(LoadCommandIndex + 1) +
+                          Twine(" extends past the end all load commands in the "
+                          "file)"));
   return getLoadCommandInfo(Obj, L.Ptr + L.C.cmdsize);
 }
 
@@ -361,7 +369,7 @@ MachOObjectFile::MachOObjectFile(MemoryB
       Libraries.push_back(Load.Ptr);
     }
     if (I < LoadCommandCount - 1) {
-      if (auto LoadOrErr = getNextLoadCommandInfo(this, Load))
+      if (auto LoadOrErr = getNextLoadCommandInfo(this, I, Load))
         Load = *LoadOrErr;
       else {
         Err = LoadOrErr.takeError();

Added: llvm/trunk/test/Object/Inputs/macho64-invalid-incomplete-load-command.1
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho64-invalid-incomplete-load-command.1?rev=268403&view=auto
==============================================================================
Binary file - no diff available.

Propchange: llvm/trunk/test/Object/Inputs/macho64-invalid-incomplete-load-command.1
------------------------------------------------------------------------------
    svn:mime-type = application/octet-stream

Modified: llvm/trunk/test/Object/macho-invalid.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/macho-invalid.test?rev=268403&r1=268402&r2=268403&view=diff
==============================================================================
--- llvm/trunk/test/Object/macho-invalid.test (original)
+++ llvm/trunk/test/Object/macho-invalid.test Tue May  3 12:16:08 2016
@@ -9,6 +9,10 @@ RUN: not llvm-objdump -macho -private-he
 RUN:      | FileCheck -check-prefix INCOMPLETE-LOADC %s
 INCOMPLETE-LOADC: truncated or malformed object (load command 0 extends past the end all load commands in the file)
 
+RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho64-invalid-incomplete-load-command.1 2>&1 \
+RUN:      | FileCheck -check-prefix INCOMPLETE-LOADC-1 %s
+INCOMPLETE-LOADC-1: truncated or malformed object (load command 1 extends past the end all load commands in the file)
+
 RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-too-small-load-command 2>&1 \
 RUN:      | FileCheck -check-prefix SMALL-LOADC-SIZE %s
 RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho64-invalid-too-small-load-command 2>&1 \