1 files changed, 6 insertions, 1 deletions
diff --git a/libgo/go/archive/zip/reader.go b/libgo/go/archive/zip/reader.go
index c10f29a..f19cf2d 100644
--- a/libgo/go/archive/zip/reader.go
+++ b/libgo/go/archive/zip/reader.go
@@ -353,6 +353,11 @@ func readDirectoryEnd(r io.ReaderAt, size int64) (dir *directoryEnd, err error)
 	if err != nil {
 		return nil, err
 	}
+
+	// Make sure directoryOffset points to somewhere in our file.
+	if o := int64(d.directoryOffset); o < 0 || o >= size {
+		return nil, ErrFormat
+	}
 	return d, nil
 }
 
@@ -407,7 +412,7 @@ func findSignatureInBlock(b []byte) int {
 		if b[i] == 'P' && b[i+1] == 'K' && b[i+2] == 0x05 && b[i+3] == 0x06 {
 			// n is length of comment
 			n := int(b[i+directoryEndLen-2]) | int(b[i+directoryEndLen-1])<<8
-			if n+directoryEndLen+i == len(b) {
+			if n+directoryEndLen+i <= len(b) {
 				return i
 			}
 		}