pkg/subsystem/linux: add custom call lists

This information will let us extract subsystems from reproducers.

3 files changed, 82 insertions, 1 deletions

diff --git a/pkg/subsystem/linux/rules.go b/pkg/subsystem/linux/rules.go
index 2df641c5e..946191263 100644
--- a/pkg/subsystem/linux/rules.go
+++ b/pkg/subsystem/linux/rules.go
@@ -9,5 +9,46 @@ type customRules struct {
 }
 
 var (
-	linuxSubsystemRules = &customRules{}
+	linuxSubsystemRules = &customRules{
+		subsystemCalls: map[string][]string{
+			"adfs":     {"syz_mount_image$adfs"},
+			"affs":     {"syz_mount_image$affs"},
+			"befs":     {"syz_mount_image$befs"},
+			"bfs":      {"syz_mount_image$bfs"},
+			"btrfs":    {"syz_mount_image$btrfs"},
+			"cramfs":   {"syz_mount_image$cramfs"},
+			"efs":      {"syz_mount_image$efs"},
+			"erofs":    {"syz_mount_image$erofs"},
+			"exfat":    {"syz_mount_image$exfat"},
+			"ext4":     {"syz_mount_image$ext4"},
+			"f2fs":     {"syz_mount_image$f2fs"},
+			"fat":      {"syz_mount_image$msdos", "syz_mount_image$vfat"},
+			"gfs2":     {"syz_mount_image$gfs2", "syz_mount_image$gfs2meta"},
+			"hfs":      {"syz_mount_image$hfs"},
+			"hfsplus":  {"syz_mount_image$hfsplus"},
+			"hpfs":     {"syz_mount_image$hpfs"},
+			"iso9660":  {"syz_mount_image$iso9660"},
+			"jffs2":    {"syz_mount_image$jffs2"},
+			"jfs":      {"syz_mount_image$jfs"},
+			"minix":    {"syz_mount_image$minix"},
+			"nilfs2":   {"syz_mount_image$nilfs2"},
+			"ntfs":     {"syz_mount_image$ntfs"},
+			"ntfs3":    {"syz_mount_image$ntfs3"},
+			"ocfs2":    {"syz_mount_image$ocfs2"},
+			"omfs":     {"syz_mount_image$omfs"},
+			"qnx4":     {"syz_mount_image$qnx4"},
+			"qnx6":     {"syz_mount_image$qnx6"},
+			"reiserfs": {"syz_mount_image$reiserfs"},
+			"romfs":    {"syz_mount_image$romfs"},
+			"squashfs": {"syz_mount_image$squashfs"},
+			"sysv":     {"syz_mount_image$sysv"},
+			"tmpfs":    {"syz_mount_image$tmpfs"},
+			"ubifs":    {"syz_mount_image$ubifs"},
+			"udf":      {"syz_mount_image$udf"},
+			"ufs":      {"syz_mount_image$ufs"},
+			"vxfs":     {"syz_mount_image$vxfs"},
+			"xfs":      {"syz_mount_image$xfs"},
+			"zonefs":   {"syz_mount_image$zonefs"},
+		},
+	}
 )
diff --git a/pkg/subsystem/linux/subsystems.go b/pkg/subsystem/linux/subsystems.go
index 468ba5fbc..9d9688758 100644
--- a/pkg/subsystem/linux/subsystems.go
+++ b/pkg/subsystem/linux/subsystems.go
@@ -85,9 +85,19 @@ func (ctx *linuxCtx) getSubsystems() ([]*entity.Subsystem, error) {
 	if err := setSubsystemNames(ret); err != nil {
 		return nil, fmt.Errorf("failed to set names: %w", err)
 	}
+	ctx.applyExtraRules(ret)
 	return ret, nil
 }
 
+func (ctx *linuxCtx) applyExtraRules(list []*entity.Subsystem) {
+	if ctx.extraRules == nil {
+		return
+	}
+	for _, entry := range list {
+		entry.Syscalls = ctx.extraRules.subsystemCalls[entry.Name]
+	}
+}
+
 func mergeRawRecords(subsystem *entity.Subsystem, records []*maintainersRecord) {
 	unique := func(list []string) []string {
 		m := make(map[string]struct{})
diff --git a/pkg/subsystem/linux/subsystems_test.go b/pkg/subsystem/linux/subsystems_test.go
index caf675244..4a1ff9f0d 100644
--- a/pkg/subsystem/linux/subsystems_test.go
+++ b/pkg/subsystem/linux/subsystems_test.go
@@ -47,6 +47,29 @@ func TestGroupLinuxSubsystems(t *testing.T) {
 	assert.ElementsMatch(t, subsystems, expected)
 }
 
+func TestCustomCallRules(t *testing.T) {
+	subsystems, err := listFromRepoInner(
+		prepareTestLinuxRepo(t, []byte(testMaintainers)),
+		testRules,
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	expectCalls := map[string][]string{
+		"ext4": []string{"syz_mount_image$ext4"},
+	}
+	gotCalls := map[string][]string{}
+	for _, s := range subsystems {
+		if len(s.Syscalls) > 0 {
+			gotCalls[s.Name] = s.Syscalls
+		}
+	}
+	assert.Equal(t, len(expectCalls), len(gotCalls))
+	for name, expect := range expectCalls {
+		assert.ElementsMatchf(t, expect, gotCalls[name], "syscalls of %s", name)
+	}
+}
+
 func prepareTestLinuxRepo(t *testing.T, maintainers []byte) fs.FS {
 	return fstest.MapFS{
 		`fs/ext4/fsync.c`:        {},
@@ -64,6 +87,13 @@ func prepareTestLinuxRepo(t *testing.T, maintainers []byte) fs.FS {
 }
 
 var (
+	testRules = &customRules{
+		subsystemCalls: map[string][]string{
+			"ext4":  []string{"syz_mount_image$ext4"},
+			"vxfs":  []string{"syz_mount_image$vxfs"},
+			"tmpfs": []string{"syz_mount_image$tmpfs"},
+		},
+	}
 	testMaintainers = `
 Maintainers List
 ----------------