Pass baseline config around

Add new new Syzkaller configuration option kernel_baseline_config. This option
is supposed to be used by kernel configruation bisection as a "good" config"

Signed-off-by: Jukka Kaartinen <jukka.kaartinen@unikie.com>
Signed-off-by: Jouni Hogander <jouni.hogander@unikie.com>

pkg/bisect/bisect.go

@@ -29,13 +29,14 @@ type Config struct {
 }
 
 type KernelConfig struct {
-	Repo      string
-	Branch    string
-	Commit    string
-	Cmdline   string
-	Sysctl    string
-	Config    []byte
-	Userspace string
+	Repo           string
+	Branch         string
+	Commit         string
+	Cmdline        string
+	Sysctl         string
+	Config         []byte
+	BaselineConfig []byte
+	Userspace      string
 }
 
 type SyzkallerConfig struct {

syz-ci/jobs.go

@@ -370,6 +370,16 @@ func (jp *JobProcessor) bisect(job *Job, mgrcfg *mgrconfig.Config) error {
 	if err := instance.OverrideVMCount(mgrcfg, bisect.NumTests); err != nil {
 		return err
 	}
+
+	var baseline []byte
+	var err error
+	// Read possible baseline for config minimization
+	if len(mgr.mgrcfg.KernelBaselineConfig) != 0 {
+		baseline, err = ioutil.ReadFile(mgr.mgrcfg.KernelBaselineConfig)
+		if err != nil {
+			return err
+		}
+	}
 	trace := new(bytes.Buffer)
 	cfg := &bisect.Config{
 		Trace:    io.MultiWriter(trace, log.VerboseWriter(3)),
@@ -377,13 +387,14 @@ func (jp *JobProcessor) bisect(job *Job, mgrcfg *mgrconfig.Config) error {
 		Fix:      req.Type == dashapi.JobBisectFix,
 		BinDir:   jp.cfg.BisectBinDir,
 		Kernel: bisect.KernelConfig{
-			Repo:      mgr.mgrcfg.Repo,
-			Branch:    mgr.mgrcfg.Branch,
-			Commit:    req.KernelCommit,
-			Cmdline:   mgr.mgrcfg.KernelCmdline,
-			Sysctl:    mgr.mgrcfg.KernelSysctl,
-			Config:    req.KernelConfig,
-			Userspace: mgr.mgrcfg.Userspace,
+			Repo:           mgr.mgrcfg.Repo,
+			Branch:         mgr.mgrcfg.Branch,
+			Commit:         req.KernelCommit,
+			Cmdline:        mgr.mgrcfg.KernelCmdline,
+			Sysctl:         mgr.mgrcfg.KernelSysctl,
+			Config:         req.KernelConfig,
+			BaselineConfig: baseline,
+			Userspace:      mgr.mgrcfg.Userspace,
 		},
 		Syzkaller: bisect.SyzkallerConfig{
 			Repo:   jp.syzkallerRepo,

syz-ci/syz-ci.go

@@ -108,6 +108,8 @@ type ManagerConfig struct {
 	Compiler     string `json:"compiler"`
 	Userspace    string `json:"userspace"`
 	KernelConfig string `json:"kernel_config"`
+	// Baseline config for bisection, see pkg/bisect.KernelConfig.BaselineConfig
+	KernelBaselineConfig string `json:"kernel_baseline_config"`
 	// File with kernel cmdline values (optional).
 	KernelCmdline string `json:"kernel_cmdline"`
 	// File with sysctl values (e.g. output of sysctl -a, optional).

syz-ci/testdata/example.cfg

@@ -15,6 +15,7 @@
 			"compiler": "/syzkaller/gcc/bin/gcc",
 			"userspace": "/syzkaller/wheezy",
 			"kernel_config": "/syzkaller/kasan.config",
+			"kernel_baseline_config": "/syzkaller/kasan_baseline.config",
 			"manager_config": {
 				"target": "linux/amd64",
 				"sandbox": "namespace",