1 files changed, 42 insertions, 14 deletions

diff --git a/src/pkg/debug/pe/file.go b/src/pkg/debug/pe/file.go
index f521566ef..ce6f1408f 100644
--- a/src/pkg/debug/pe/file.go
+++ b/src/pkg/debug/pe/file.go
@@ -13,13 +13,15 @@ import (
 	"io"
 	"os"
 	"strconv"
+	"unsafe"
 )
 
 // A File represents an open PE file.
 type File struct {
 	FileHeader
-	Sections []*Section
-	Symbols  []*Symbol
+	OptionalHeader interface{} // of type *OptionalHeader32 or *OptionalHeader64
+	Sections       []*Section
+	Symbols        []*Symbol
 
 	closer io.Closer
 }
@@ -72,6 +74,9 @@ type ImportDirectory struct {
 func (s *Section) Data() ([]byte, error) {
 	dat := make([]byte, s.sr.Size())
 	n, err := s.sr.ReadAt(dat, 0)
+	if n == len(dat) {
+		err = nil
+	}
 	return dat[0:n], err
 }
 
@@ -193,10 +198,33 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		}
 	}
 
-	// Process sections.
+	// Read optional header.
 	sr.Seek(base, os.SEEK_SET)
-	binary.Read(sr, binary.LittleEndian, &f.FileHeader)
-	sr.Seek(int64(f.FileHeader.SizeOfOptionalHeader), os.SEEK_CUR) //Skip OptionalHeader
+	if err := binary.Read(sr, binary.LittleEndian, &f.FileHeader); err != nil {
+		return nil, err
+	}
+	var oh32 OptionalHeader32
+	var oh64 OptionalHeader64
+	switch uintptr(f.FileHeader.SizeOfOptionalHeader) {
+	case unsafe.Sizeof(oh32):
+		if err := binary.Read(sr, binary.LittleEndian, &oh32); err != nil {
+			return nil, err
+		}
+		if oh32.Magic != 0x10b { // PE32
+			return nil, fmt.Errorf("pe32 optional header has unexpected Magic of 0x%x", oh32.Magic)
+		}
+		f.OptionalHeader = &oh32
+	case unsafe.Sizeof(oh64):
+		if err := binary.Read(sr, binary.LittleEndian, &oh64); err != nil {
+			return nil, err
+		}
+		if oh64.Magic != 0x20b { // PE32+
+			return nil, fmt.Errorf("pe32+ optional header has unexpected Magic of 0x%x", oh64.Magic)
+		}
+		f.OptionalHeader = &oh64
+	}
+
+	// Process sections.
 	f.Sections = make([]*Section, f.FileHeader.NumberOfSections)
 	for i := 0; i < int(f.FileHeader.NumberOfSections); i++ {
 		sh := new(SectionHeader32)
@@ -213,15 +241,15 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		s := new(Section)
 		s.SectionHeader = SectionHeader{
 			Name:                 name,
-			VirtualSize:          uint32(sh.VirtualSize),
-			VirtualAddress:       uint32(sh.VirtualAddress),
-			Size:                 uint32(sh.SizeOfRawData),
-			Offset:               uint32(sh.PointerToRawData),
-			PointerToRelocations: uint32(sh.PointerToRelocations),
-			PointerToLineNumbers: uint32(sh.PointerToLineNumbers),
-			NumberOfRelocations:  uint16(sh.NumberOfRelocations),
-			NumberOfLineNumbers:  uint16(sh.NumberOfLineNumbers),
-			Characteristics:      uint32(sh.Characteristics),
+			VirtualSize:          sh.VirtualSize,
+			VirtualAddress:       sh.VirtualAddress,
+			Size:                 sh.SizeOfRawData,
+			Offset:               sh.PointerToRawData,
+			PointerToRelocations: sh.PointerToRelocations,
+			PointerToLineNumbers: sh.PointerToLineNumbers,
+			NumberOfRelocations:  sh.NumberOfRelocations,
+			NumberOfLineNumbers:  sh.NumberOfLineNumbers,
+			Characteristics:      sh.Characteristics,
 		}
 		s.sr = io.NewSectionReader(r, int64(s.SectionHeader.Offset), int64(s.SectionHeader.Size))
 		s.ReaderAt = s.sr