From b0131d4eefe908aef51ea88be98dc8a926023371 Mon Sep 17 00:00:00 2001
From: Dmitry Vyukov <dvyukov@google.com>
Date: Fri, 20 Nov 2015 19:58:27 +0100
Subject: [PATCH] manager: add support for suppressions

There are always some known bugs...
---
 manager/main.go | 18 ++++++++++++++++++
 vm/qemu/qemu.go | 20 ++++++++++++++------
 vm/vm.go        |  2 ++
 3 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/manager/main.go b/manager/main.go
index b539e1f5..c6766176 100644
--- a/manager/main.go
+++ b/manager/main.go
@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"log"
+	"regexp"
 	"strings"
 
 	"github.com/google/syzkaller/sys"
@@ -37,6 +38,7 @@ type Config struct {
 	Params           map[string]interface{}
 	Enable_Syscalls  []string
 	Disable_Syscalls []string
+	Suppressions     []string
 }
 
 func main() {
@@ -62,6 +64,22 @@ func main() {
 		EnabledSyscalls: enabledSyscalls,
 		NoCover:         cfg.Nocover,
 	}
+
+	// Add some builtin suppressions.
+	cfg.Suppressions = append(cfg.Suppressions, []string{
+		"panic: failed to start executor binary",
+		"panic: executor failed: pthread_create failed",
+		"panic: failed to create temp dir",
+		"Out of memory: Kill process .* \\(syzkaller_fuzze\\)",
+	}...)
+	for _, s := range cfg.Suppressions {
+		re, err := regexp.Compile(s)
+		if err != nil {
+			fatalf("failed to compile suppression '%v': %v", s, err)
+		}
+		vmCfg.Suppressions = append(vmCfg.Suppressions, re)
+	}
+
 	var instances []vm.Instance
 	for i := 0; i < cfg.Count; i++ {
 		inst, err := vm.Create(cfg.Type, vmCfg, i)
diff --git a/vm/qemu/qemu.go b/vm/qemu/qemu.go
index bcd1f3e5..be62c343 100644
--- a/vm/qemu/qemu.go
+++ b/vm/qemu/qemu.go
@@ -34,7 +34,7 @@ type qemu struct {
 	crashdir  string
 	callsFlag string
 	id        int
-	mgrPort   int
+	cfg       *vm.Config
 }
 
 type params struct {
@@ -92,7 +92,7 @@ func ctor(cfg *vm.Config, index int) (vm.Instance, error) {
 		workdir:  workdir,
 		crashdir: crashdir,
 		id:       index,
-		mgrPort:  cfg.ManagerPort,
+		cfg:      cfg,
 	}
 
 	if cfg.EnabledSyscalls != "" {
@@ -147,7 +147,7 @@ func (q *qemu) Run() {
 			log:       logf,
 			rpipe:     rpipe,
 			wpipe:     wpipe,
-			mgrPort:   q.mgrPort,
+			cfg:       q.cfg,
 			cmds:      make(map[*Command]bool),
 		}
 		inst.Run()
@@ -167,7 +167,7 @@ type Instance struct {
 	log       *os.File
 	rpipe     *os.File
 	wpipe     *os.File
-	mgrPort   int
+	cfg       *vm.Config
 	cmds      map[*Command]bool
 	qemu      *Command
 }
@@ -273,7 +273,7 @@ func (inst *Instance) Run() {
 
 	// Run the binary.
 	cmd := inst.CreateSSHCommand(fmt.Sprintf("/syzkaller_fuzzer -name %v -executor /syzkaller_executor -manager %v:%v %v",
-		inst.name, hostAddr, inst.mgrPort, inst.callsFlag))
+		inst.name, hostAddr, inst.cfg.ManagerPort, inst.callsFlag))
 
 	deadline := start.Add(time.Hour)
 	lastOutput := time.Now()
@@ -350,7 +350,15 @@ func (inst *Instance) Run() {
 }
 
 func (inst *Instance) SaveCrasher(output []byte) {
-	ioutil.WriteFile(filepath.Join(inst.crashdir, fmt.Sprintf("crash%v-%v", inst.id, time.Now().UnixNano())), output, 0660)
+	for _, re := range inst.cfg.Suppressions {
+		if re.Match(output) {
+			log.Printf("qemu/%v: suppressing '%v'", inst.id, re.String())
+			return
+		}
+	}
+	filename := fmt.Sprintf("crash%v-%v", inst.id, time.Now().UnixNano())
+	log.Printf("qemu/%v: saving crash to %v", inst.id, filename)
+	ioutil.WriteFile(filepath.Join(inst.crashdir, filename), output, 0660)
 }
 
 func (inst *Instance) Shutdown() {
diff --git a/vm/vm.go b/vm/vm.go
index c49d5b75..e6430ec4 100644
--- a/vm/vm.go
+++ b/vm/vm.go
@@ -5,6 +5,7 @@ package vm
 
 import (
 	"fmt"
+	"regexp"
 )
 
 type Instance interface {
@@ -16,6 +17,7 @@ type Config struct {
 	ManagerPort     int
 	Params          []byte
 	EnabledSyscalls string
+	Suppressions    []*regexp.Regexp
 	NoCover         bool
 }