[llvm] r280267 - Next set of additional error checks for invalid Mach-O files for bad load commands

Kevin Enderby via llvm-commits llvm-commits at lists.llvm.org
Wed Aug 31 10:57:47 PDT 2016


Author: enderby
Date: Wed Aug 31 12:57:46 2016
New Revision: 280267

URL: http://llvm.org/viewvc/llvm-project?rev=280267&view=rev
Log:
Next set of additional error checks for invalid Mach-O files for bad load commands
that use the Mach::linkedit_data_command type for the load commands that are
currently used in the MachOObjectFile constructor.

This contains the missing checks for LC_DATA_IN_CODE and
LC_LINKER_OPTIMIZATION_HINT load commands and the fields for the
Mach::linkedit_data_command type.  Checking for other load commands that
use this type will be added later.

Also fixed a couple of places that was using sizeof(MachOObjectFile::LoadCommandInfo)
that should have been using sizeof(MachO::load_command).

Added:
    llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-bad-size   (with props)
    llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-dataoff-datasize   (with props)
    llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-more-than-one   (with props)
    llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-dataoff   (with props)
    llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-small   (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=280267&r1=280266&r2=280267&view=diff
==============================================================================
--- llvm/trunk/lib/Object/MachOObjectFile.cpp (original)
+++ llvm/trunk/lib/Object/MachOObjectFile.cpp Wed Aug 31 12:57:46 2016
@@ -184,7 +184,7 @@ static Expected<MachOObjectFile::LoadCom
 getFirstLoadCommandInfo(const MachOObjectFile *Obj) {
   unsigned HeaderSize = Obj->is64Bit() ? sizeof(MachO::mach_header_64)
                                        : sizeof(MachO::mach_header);
-  if (sizeof(MachOObjectFile::LoadCommandInfo) > Obj->getHeader().sizeofcmds)
+  if (sizeof(MachO::load_command) > Obj->getHeader().sizeofcmds)
     return malformedError("load command 0 extends past the end all load "
                           "commands in the file");
   return getLoadCommandInfo(Obj, getPtr(Obj, HeaderSize), 0);
@@ -195,7 +195,7 @@ getNextLoadCommandInfo(const MachOObject
                        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) >
+  if (L.Ptr + L.C.cmdsize + sizeof(MachO::load_command) >
       Obj->getData().data() + HeaderSize + Obj->getHeader().sizeofcmds)
     return malformedError("load command " + Twine(LoadCommandIndex + 1) +
                           " extends past the end all load commands in the file");
@@ -474,6 +474,36 @@ static Error checkDysymtabCommand(const
   return Error::success();
 }
 
+static Error checkLinkeditDataCommand(const MachOObjectFile *Obj,
+                                 const MachOObjectFile::LoadCommandInfo &Load,
+                                 uint32_t LoadCommandIndex,
+                                 const char **LoadCmd, const char *CmdName) {
+  if (Load.C.cmdsize < sizeof(MachO::linkedit_data_command))
+    return malformedError("load command " + Twine(LoadCommandIndex) + " " +
+                          CmdName + " cmdsize too small");
+  if (*LoadCmd != nullptr)
+    return malformedError("more than one " + Twine(CmdName) + " command");
+  MachO::linkedit_data_command LinkData =
+    getStruct<MachO::linkedit_data_command>(Obj, Load.Ptr);
+  if (LinkData.cmdsize != sizeof(MachO::linkedit_data_command))
+    return malformedError(Twine(CmdName) + " command " +
+                          Twine(LoadCommandIndex) + " has incorrect cmdsize");
+  uint64_t FileSize = Obj->getData().size();
+  if (LinkData.dataoff > FileSize)
+    return malformedError("dataoff field of " + Twine(CmdName) + " command " +
+                          Twine(LoadCommandIndex) + " extends past the end of "
+                          "the file");
+  uint64_t BigSize = LinkData.dataoff;
+  BigSize += LinkData.datasize;
+  if (BigSize > FileSize)
+    return malformedError("dataoff field plus datasize field of " +
+                          Twine(CmdName) + " command " +
+                          Twine(LoadCommandIndex) + " extends past the end of "
+                          "the file");
+  *LoadCmd = Load.Ptr;
+  return Error::success();
+}
+
 Expected<std::unique_ptr<MachOObjectFile>>
 MachOObjectFile::create(MemoryBufferRef Object, bool IsLittleEndian,
                         bool Is64Bits) {
@@ -550,19 +580,13 @@ MachOObjectFile::MachOObjectFile(MemoryB
       if ((Err = checkDysymtabCommand(this, Load, I, &DysymtabLoadCmd)))
         return;
     } else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
-      // Multiple data in code tables
-      if (DataInCodeLoadCmd) {
-        Err = malformedError("Multiple data-in-code tables");
+      if ((Err = checkLinkeditDataCommand(this, Load, I, &DataInCodeLoadCmd,
+                                          "LC_DATA_IN_CODE")))
         return;
-      }
-      DataInCodeLoadCmd = Load.Ptr;
     } else if (Load.C.cmd == MachO::LC_LINKER_OPTIMIZATION_HINT) {
-      // Multiple linker optimization hint tables
-      if (LinkOptHintsLoadCmd) {
-        Err = malformedError("Multiple linker optimization hint tables");
+      if ((Err = checkLinkeditDataCommand(this, Load, I, &LinkOptHintsLoadCmd,
+                                          "LC_LINKER_OPTIMIZATION_HINT")))
         return;
-      }
-      LinkOptHintsLoadCmd = Load.Ptr;
     } else if (Load.C.cmd == MachO::LC_DYLD_INFO ||
                Load.C.cmd == MachO::LC_DYLD_INFO_ONLY) {
       // Multiple dyldinfo load commands

Added: llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-bad-size
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-bad-size?rev=280267&view=auto
==============================================================================
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Propchange: llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-bad-size
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Added: llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-dataoff-datasize
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-dataoff-datasize?rev=280267&view=auto
==============================================================================
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Propchange: llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-dataoff-datasize
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Added: llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-more-than-one
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-more-than-one?rev=280267&view=auto
==============================================================================
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Propchange: llvm/trunk/test/Object/Inputs/macho-invalid-dataincode-more-than-one
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Added: llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-dataoff
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-dataoff?rev=280267&view=auto
==============================================================================
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Propchange: llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-dataoff
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Added: llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-small
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-small?rev=280267&view=auto
==============================================================================
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Propchange: llvm/trunk/test/Object/Inputs/macho-invalid-linkopthint-small
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Modified: llvm/trunk/test/Object/macho-invalid.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/macho-invalid.test?rev=280267&r1=280266&r2=280267&view=diff
==============================================================================
--- llvm/trunk/test/Object/macho-invalid.test (original)
+++ llvm/trunk/test/Object/macho-invalid.test Wed Aug 31 12:57:46 2016
@@ -208,3 +208,19 @@ INVALID-DYSYMTAB-TOCOFF-LOCRELOFF: macho
 
 RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-dysymtab-locreloff-nlocrel 2>&1 | FileCheck -check-prefix INVALID-DYSYMTAB-TOCOFF-LOCRELOFF-NLOCREL %s
 INVALID-DYSYMTAB-TOCOFF-LOCRELOFF-NLOCREL: macho-invalid-dysymtab-locreloff-nlocrel': truncated or malformed object (locreloff field plus nlocrel field times sizeof(struct relocation_info) of LC_DYSYMTAB command 0 extends past the end of the file)
+
+RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-dataincode-more-than-one 2>&1 | FileCheck -check-prefix INVALID-DATAINCODE-MORE-THAN-ONE %s
+INVALID-DATAINCODE-MORE-THAN-ONE: macho-invalid-dataincode-more-than-one': truncated or malformed object (more than one LC_DATA_IN_CODE command)
+
+RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-linkopthint-small 2>&1 | FileCheck -check-prefix INVALID-LINKOPTHINT-SMALL %s
+INVALID-LINKOPTHINT-SMALL: macho-invalid-linkopthint-small': truncated or malformed object (load command 0 LC_LINKER_OPTIMIZATION_HINT cmdsize too small)
+
+RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-dataincode-bad-size 2>&1 | FileCheck -check-prefix INVALID-DATAINCODE-BAD-SIZE %s
+INVALID-DATAINCODE-BAD-SIZE: macho-invalid-dataincode-bad-size': truncated or malformed object (LC_DATA_IN_CODE command 0 has incorrect cmdsize)
+
+RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-linkopthint-dataoff 2>&1 | FileCheck -check-prefix INVALID-LINKOPTHINT-DATAOFF %s
+INVALID-LINKOPTHINT-DATAOFF: macho-invalid-linkopthint-dataoff': truncated or malformed object (dataoff field of LC_LINKER_OPTIMIZATION_HINT command 0 extends past the end of the file)
+
+RUN: not llvm-objdump -macho -private-headers %p/Inputs/macho-invalid-dataincode-dataoff-datasize 2>&1 | FileCheck -check-prefix INVALID-DATAINCODE-DATAOFF-DATASIZE %s
+INVALID-DATAINCODE-DATAOFF-DATASIZE: macho-invalid-dataincode-dataoff-datasize': truncated or malformed object (dataoff field plus datasize field of LC_DATA_IN_CODE command 0 extends past the end of the file)
+




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