From 48ec7344e13eaeee104976fb52d3ed30c1073d5d Mon Sep 17 00:00:00 2001
From: Aleksandr Nogikh <nogikh@google.com>
Date: Wed, 14 Dec 2022 19:23:40 +0100
Subject: pkg/subsystem: extract subsystems from syz_mount_image$ calls

Dump the mapping between the currently available pseudo syscalls and the
corresponding subsystems.
---
 dashboard/app/config_linux_test.go |  4 +++
 pkg/subsystem/extract.go           | 53 ++++++++++++++++++++++++++++++++++++++
 pkg/subsystem/extract_test.go      | 41 +++++++++++++++++++++++++++++
 3 files changed, 98 insertions(+)
 create mode 100644 dashboard/app/config_linux_test.go

diff --git a/dashboard/app/config_linux_test.go b/dashboard/app/config_linux_test.go
new file mode 100644
index 000000000..c95204de3
--- /dev/null
+++ b/dashboard/app/config_linux_test.go
@@ -0,0 +1,4 @@
+// Copyright 2022 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package main
diff --git a/pkg/subsystem/extract.go b/pkg/subsystem/extract.go
index 181c15835..e29fbab01 100644
--- a/pkg/subsystem/extract.go
+++ b/pkg/subsystem/extract.go
@@ -24,6 +24,7 @@ type Crash struct {
 func MakeLinuxSubsystemExtractor() *SubsystemExtractor {
 	return &SubsystemExtractor{
 		pathToSubsystems: linuxPathToSubsystems,
+		callToSubsystems: linuxCallToSubsystems,
 	}
 }
 
@@ -60,6 +61,58 @@ func linuxPathToSubsystems(path string) []string {
 	return ret
 }
 
+func linuxCallToSubsystems(call string) []string {
+	name := linuxCallToSubsystemsMap[call]
+	if name != "" {
+		return []string{name}
+	}
+	return nil
+}
+
+var linuxCallToSubsystemsMap = map[string]string{
+	"syz_mount_image$adfs":     "adfs",
+	"syz_mount_image$affs":     "affs",
+	"syz_mount_image$befs":     "befs",
+	"syz_mount_image$bfs":      "bfs",
+	"syz_mount_image$btrfs":    "btrfs",
+	"syz_mount_image$cramfs":   "cramfs",
+	"syz_mount_image$efs":      "efs",
+	"syz_mount_image$erofs":    "erofs",
+	"syz_mount_image$exfat":    "exfat",
+	"syz_mount_image$ext4":     "ext4",
+	"syz_mount_image$f2fs":     "f2fs",
+	"syz_mount_image$gfs2":     "gfs2",
+	"syz_mount_image$gfs2meta": "gfs2",
+	"syz_mount_image$hfs":      "hfs",
+	"syz_mount_image$hfsplus":  "hfsplus",
+	"syz_mount_image$hpfs":     "hpfs",
+	"syz_mount_image$iso9660":  "iso9660",
+	"syz_mount_image$jffs2":    "jffs2",
+	"syz_mount_image$jfs":      "jfs",
+	"syz_mount_image$minix":    "minix",
+	"syz_mount_image$msdos":    "fat",
+	"syz_mount_image$nilfs2":   "nilfs2",
+	"syz_mount_image$ntfs":     "ntfs",
+	"syz_mount_image$ntfs3":    "ntfs3",
+	"syz_mount_image$ocfs2":    "ocfs2",
+	"syz_mount_image$omfs":     "omfs",
+	"syz_mount_image$qnx4":     "qnx4",
+	"syz_mount_image$qnx6":     "qnx6",
+	"syz_mount_image$reiserfs": "reiserfs",
+	"syz_mount_image$romfs":    "romfs",
+	"syz_mount_image$squashfs": "squashfs",
+	"syz_mount_image$sysv":     "sysv",
+	"syz_mount_image$tmpfs":    "tmpfs",
+	"syz_mount_image$ubifs":    "ubifs",
+	"syz_mount_image$udf":      "udf",
+	"syz_mount_image$ufs":      "ufs",
+	"syz_mount_image$v7":       "v7",
+	"syz_mount_image$vfat":     "vfat",
+	"syz_mount_image$vxfs":     "vxfs",
+	"syz_mount_image$xfs":      "xfs",
+	"syz_mount_image$zonefs":   "zonefs",
+}
+
 var (
 	vfsPathRegexp = regexp.MustCompile(`^fs/[^/]+\.c`)
 )
diff --git a/pkg/subsystem/extract_test.go b/pkg/subsystem/extract_test.go
index 29512f460..862d1a6e5 100644
--- a/pkg/subsystem/extract_test.go
+++ b/pkg/subsystem/extract_test.go
@@ -4,6 +4,7 @@
 package subsystem
 
 import (
+	"reflect"
 	"sort"
 	"testing"
 
@@ -67,3 +68,43 @@ io_uring_enter(r0, 0x2ff, 0x0, 0x0, 0x0, 0x0)`,
 	assert.Exactlyf(t, ret, []string{"io_uring", "tty", "tty_ioctls"},
 		"invalid resulting subsystems: %s", ret)
 }
+
+func TestFsSubsystemExtraction(t *testing.T) {
+	extractor := MakeLinuxSubsystemExtractor()
+
+	tests := []struct {
+		guilty     string
+		prog       string
+		subsystems []string
+	}{
+		{
+			guilty: "fs/nilfs2/dat.c",
+			// nolint: lll
+			prog: `syz_mount_image$nilfs2(&(0x7f0000000000), &(0x7f0000000100)='./file0\x00', 0x100000, 0x3b, &(0x7f0000000200)=[{&(0x7f0000011240)="02", 0x1}, {&(0x7f0000012a40)="03000000", 0x4, 0x1}], 0x0, &(0x7f00000131c0), 0x1)
+openat$incfs(0xffffffffffffff9c, &(0x7f0000000000)='.pending_reads\x00', 0x4040, 0x0)`,
+			subsystems: []string{"nilfs2"},
+		},
+		{
+			guilty: "fs/namei.c",
+			// nolint: lll
+			prog: `syz_mount_image$ntfs3(&(0x7f0000000240), &(0x7f000001f3c0)='./file0\x00', 0xc40, &(0x7f00000005c0)=ANY=[@ANYBLOB="0032"], 0x3, 0x1f398, &(0x7f000003e7c0)="111")
+r0 = openat(0xffffffffffffff9c, &(0x7f0000000040)='.\x00', 0x0, 0x0)
+mkdirat(r0, &(0x7f0000000180)='./bus\x00', 0x0)
+mkdirat(r0, &(0x7f0000000280)='./bus/file0\x00', 0x0)
+renameat2(r0, &(0x7f00000004c0)='./file0\x00', r0, &(0x7f0000000500)='./bus/file0/file0\x00', 0x0)`,
+			subsystems: []string{"ntfs3", "vfs"},
+		},
+	}
+
+	for i, test := range tests {
+		ret := extractor.Extract(&Crash{
+			OS:          targets.Linux,
+			GuiltyFiles: []string{test.guilty},
+			SyzRepro:    test.prog,
+		})
+		sort.Strings(ret)
+		if !reflect.DeepEqual(ret, test.subsystems) {
+			t.Fatalf("test #%d: got %+v, wanted %+v", i, ret, test.subsystems)
+		}
+	}
+}
-- 
cgit mrf-deployment