syz-cluster: report reproducers for findings

Move C repro generation from syz-manager to pkg/repro to avoid code
duplication.

Author: a-nogikh

pkg/repro/repro.go

@@ -989,3 +989,15 @@ func (stats *Stats) FullLog() []byte {
 		stats.ExtractProgTime, stats.MinimizeProgTime,
 		stats.SimplifyProgTime, stats.ExtractCTime, stats.SimplifyCTime, stats.Log))
 }
+
+func (repro *Result) CProgram() ([]byte, error) {
+	cprog, err := csource.Write(repro.Prog, repro.Opts)
+	if err == nil {
+		formatted, err := csource.Format(cprog)
+		if err == nil {
+			return formatted, nil
+		}
+		return cprog, nil
+	}
+	return nil, err
+}

syz-cluster/workflow/fuzz-step/main.go

@@ -259,7 +259,19 @@ func reportFinding(ctx context.Context, client *api.Client, bug *manager.UniqueB
 		Title:     bug.Report.Title,
 		Report:    bug.Report.Report,
 		Log:       bug.Report.Output,
-		// TODO: include the reproducer.
+	}
+	if repro := bug.Repro; repro != nil {
+		if repro.Prog != nil {
+			finding.SyzRepro = repro.Prog.Serialize()
+			finding.SyzReproOpts = repro.Opts.Serialize()
+		}
+		if repro.CRepro {
+			var err error
+			finding.CRepro, err = repro.CProgram()
+			if err != nil {
+				app.Errorf("failed to generate C program: %v", err)
+			}
+		}
 	}
 	return client.UploadFinding(ctx, finding)
 }

syz-manager/manager.go

@@ -24,7 +24,6 @@ import (
 	"github.com/google/syzkaller/dashboard/dashapi"
 	"github.com/google/syzkaller/pkg/asset"
 	"github.com/google/syzkaller/pkg/corpus"
-	"github.com/google/syzkaller/pkg/csource"
 	"github.com/google/syzkaller/pkg/db"
 	"github.com/google/syzkaller/pkg/flatrpc"
 	"github.com/google/syzkaller/pkg/fuzzer"
@@ -864,14 +863,9 @@ func (mgr *Manager) saveRepro(res *manager.ReproResult) {
 
 	var cprogText []byte
 	if repro.CRepro {
-		cprog, err := csource.Write(repro.Prog, repro.Opts)
-		if err == nil {
-			formatted, err := csource.Format(cprog)
-			if err == nil {
-				cprog = formatted
-			}
-			cprogText = cprog
-		} else {
+		var err error
+		cprogText, err = repro.CProgram()
+		if err != nil {
 			log.Logf(0, "failed to write C source: %v", err)
 		}
 	}