tools/syz-imagegen: generate syz_read_part_table seeds

Fixes #3529

1 files changed, 51 insertions, 15 deletions

diff --git a/tools/syz-imagegen/imagegen.go b/tools/syz-imagegen/imagegen.go
index 4cd9806be..fdf68b721 100644
--- a/tools/syz-imagegen/imagegen.go
+++ b/tools/syz-imagegen/imagegen.go
@@ -461,6 +461,48 @@ var fileSystems = []FileSystem{
 			return err
 		},
 	},
+	{
+		Name:     parttable,
+		MinSize:  1 << 20,
+		ReadOnly: true,
+		MkfsFlagCombinations: [][]string{{
+			// You can test/explore these commands with:
+			// $ rm -f disk && touch disk && fallocate -l 16M disk && fdisk disk
+			"g n 1 34 47 n 2 48 96 n 3 97 2013 t 1 uefi t 2 linux t 3 swap w",
+			"g n 1 100 200 n 2 50 80 n 3 1000 1900 M a c r x n 1 syzkaller A 1 r w",
+			"g n 3 200 300 n 7 400 500 n 2 600 700 x l 700 r w",
+			"G n 1 16065 16265 w",
+			"G n 16 20000 30000 i w",
+			"o n p 1 2048 4096 n p 3 4097 4100 n e 2 4110 4200 a 1 t 2 a5 t 3 uefi b y x 1 e r w",
+			"o n p 1 2048 3071 n e 3 3072 32767 n 6200 7999 n 10240 20000 w",
+			"s c 1 a 2 w",
+		}},
+		Mkfs: func(image *Image) error {
+			cmd := exec.Command("fdisk", "--noauto-pt", "--color=always", image.disk)
+			cmd.Stdin = strings.NewReader(strings.Join(image.flags, "\n"))
+			output, err := osutil.Run(10*time.Minute, cmd)
+			if err != nil {
+				return err
+			}
+			// It's hard to understand if any of the commands fail,
+			// fdisk does not exit with an error and print assorted error messages.
+			// So instead we run it with --color=always and grep for red color marker
+			// in the output (ESC[31m).
+			if bytes.Contains(output, []byte{0x1b, 0x5b, 0x33, 0x31, 0x6d}) {
+				return errors.New(string(output))
+			}
+			return err
+		},
+	},
+}
+
+const parttable = "parttable"
+
+func (fs FileSystem) filePrefix() string {
+	if fs.Name == parttable {
+		return "syz_read_part_table"
+	}
+	return "syz_mount_image_" + fs.Name
 }
 
 // Image represents one image we generate for a file system.
@@ -611,7 +653,7 @@ func generateImages(target *prog.Target, flagFS string, list bool) ([]*Image, er
 			fmt.Printf("%v [%v images]\n", fs.Name, index)
 			continue
 		}
-		files, err := filepath.Glob(filepath.Join("sys", targets.Linux, "test", "syz_mount_image_"+fs.Name+"_*"))
+		files, err := filepath.Glob(filepath.Join("sys", targets.Linux, "test", fs.filePrefix()+"_*"))
 		if err != nil {
 			return nil, fmt.Errorf("error reading output dir: %v", err)
 		}
@@ -659,7 +701,7 @@ func (image *Image) generate() error {
 
 func (image *Image) generateSize() error {
 	outFile := filepath.Join("sys", targets.Linux, "test",
-		fmt.Sprintf("syz_mount_image_%v_%v", image.fs.Name, image.index))
+		fmt.Sprintf("%v_%v", image.fs.filePrefix(), image.index))
 	image.disk = outFile + ".img"
 	f, err := os.Create(image.disk)
 	if err != nil {
@@ -692,7 +734,7 @@ func (image *Image) generateSize() error {
 	image.hash = crc32.ChecksumIEEE(data)
 
 	// Write out image *with* change of directory.
-	out, err := writeImage(image, data, true)
+	out, err := writeImage(image, data)
 	if err != nil {
 		return fmt.Errorf("failed to write image: %v", err)
 	}
@@ -767,27 +809,21 @@ func runCmd(cmd string, args ...string) ([]byte, error) {
 	return osutil.RunCmd(10*time.Minute, "", cmd, args...)
 }
 
-func writeImage(image *Image, data []byte, chdir bool) ([]byte, error) {
+func writeImage(image *Image, data []byte) ([]byte, error) {
 	buf := new(bytes.Buffer)
 	fmt.Fprintf(buf, "# Code generated by tools/syz-imagegen. DO NOT EDIT.\n")
 	fmt.Fprintf(buf, "# requires: manual\n\n")
 	fmt.Fprintf(buf, "# %v\n\n", image)
 	compressedData := prog.Compress(data)
 	b64Data := prog.EncodeB64(compressedData)
-	chdirAsInt := 0
-	if chdir {
-		chdirAsInt = 1
+	if image.fs.Name == parttable {
+		fmt.Fprintf(buf, `syz_read_part_table(AUTO, &AUTO="$`)
+	} else {
+		fmt.Fprintf(buf, `syz_mount_image$%v(&AUTO='%v\x00', &AUTO='./file0\x00', 0x0, &AUTO, 0x1, AUTO, &AUTO="$`,
+			image.fs.Name, image.fs.Name)
 	}
-	fmt.Fprintf(buf, `syz_mount_image$%v(&AUTO='%v\x00', &AUTO='./file0\x00', 0x0, &AUTO, 0x%x, AUTO, &AUTO="$`,
-		image.fs.Name, image.fs.Name, chdirAsInt)
 	buf.Write(b64Data)
 	fmt.Fprintf(buf, "\")\n")
 
 	return buf.Bytes(), nil
 }
-
-// TODO: also generate syz_read_part_table tests:
-//	fmt.Fprintf(buf, `syz_read_part_table(0x%x, 0x%x, &AUTO="$`,
-//		len(data), len(compressedData))
-//  buf.Write(b64Data)
-//  fmt.Fprintf(buf, "\")\n")