Merge pull request #2 from klauspost/add-threadripper-v1-patch

Add Threadripper alternative patch

Patch by @neoKushan

README.md

@@ -1,6 +1,6 @@
 # ryzen-master-vbs-patch
 
-AMD Ryzen Master VBS patcher allows AMD Ryzen Master to run while Virtualization is enabled.
+AMD Ryzen Master VBS patcher allows AMD Ryzen Master to run while Hyper-V Virtualization is enabled.
 
 
 Thanks to [@TOM_RUS](https://twitter.com/TOM_RUS/status/1204867886197755904) for finding this.
@@ -18,8 +18,7 @@ Confirmed versions:
  * v2.1.1.1472 (2020)
  * v2.2.0.1543 (2020)
 
-Note that on Threadripper CPUs the actually installed version may be different and the installed executable therefore cannot be patched. 
-The version in the "About" page in the software should reflect the actual version. 
+Threadripper patch was supplied by [@neoKushan](https://github.com/neoKushan).
 
 # Running
 

main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"errors"
 	"flag"
 	"fmt"
 	"io/ioutil"
@@ -29,27 +30,40 @@ func main() {
 	for _, f := range args {
 		dir, file := filepath.Split(f)
 		err := patch(filepath.Join(dir, file), filepath.Join(dir, *prefix+file))
-		if err != nil {
+		switch err {
+		case nil:
+		case errCannotPatch:
+			fmt.Println(err)
+			err = patchAlt(filepath.Join(dir, file), filepath.Join(dir, *prefix+file))
+			if err == errCannotPatch {
+				fmt.Println(err)
+				fmt.Println("Skipping file...")
+			} else if err != nil {
+				fmt.Println(err)
+				os.Exit(1)
+			}
+		default:
 			fmt.Println(err)
 			os.Exit(1)
 		}
 	}
 }
 
+var errCannotPatch = errors.New("byte sequence not found")
+
 var search = []byte{0x44, 0x39, 0x6D, 0xA8, 0x0F, 0x84, 0xF7}
 var replace = []byte{0x44, 0x39, 0x6D, 0xA8, 0x90, 0xe9, 0xf7}
 
 func patch(in string, out string) error {
-	fmt.Println("Patching", in)
+	fmt.Println("Applying v2 patch on", in)
 	b, err := ioutil.ReadFile(in)
 	if err != nil {
 		return err
 	}
 	c := bytes.Count(b, search)
 	fmt.Println("Matching byte sequences:", c, "(should be 1)")
 	if c != 1 {
-		fmt.Println("Skipping file...")
-		return nil
+		return errCannotPatch
 	}
 	b = bytes.Replace(b, search, replace, -1)
 	fmt.Println("Writing to", out)
@@ -60,6 +74,29 @@ func patch(in string, out string) error {
 	return nil
 }
 
+var searchAlt = []byte{0x00, 0x39, 0x7D, 0x90, 0x0F, 0x84, 0xE8, 0x00}
+var replaceAlt = []byte{0x00, 0x39, 0x7D, 0x90, 0x90, 0xE9, 0xE8, 0x00}
+
+func patchAlt(in string, out string) error {
+	fmt.Println("Applying alternative patch on", in)
+	b, err := ioutil.ReadFile(in)
+	if err != nil {
+		return err
+	}
+	c := bytes.Count(b, searchAlt)
+	fmt.Println("Matching byte sequences:", c, "(should be 1)")
+	if c != 1 {
+		return errCannotPatch
+	}
+	b = bytes.Replace(b, searchAlt, replaceAlt, -1)
+	fmt.Println("Writing to", out)
+	err = ioutil.WriteFile(out, b, 0)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 /*
 The MIT License (MIT)