ipc: add an optional 'abort' signal

If an external sandbox process wraps the executor, it may be helpful to
send a signal other than SIGKILL to the sandbox when the program times
out or fails to respond. This gives the sandbox the opportunity to emit
additional debugging information before exiting.

Add an 'abort' signal to ipc, which is sent to the executor before
SIGKILL. If the executor fails to exit within 5s, the signal is upgraded
to SIGKILL.

The default abort signal remains SIGKILL, maintaining existing behavior.

2 files changed, 8 insertions, 8 deletions

diff --git a/tools/syz-execprog/execprog.go b/tools/syz-execprog/execprog.go
index 7e0a25d75..1992279a7 100644
--- a/tools/syz-execprog/execprog.go
+++ b/tools/syz-execprog/execprog.go
@@ -56,14 +56,14 @@ func main() {
 		return
 	}
 
-	flags, timeout, err := ipc.DefaultFlags()
+	config, err := ipc.DefaultConfig()
 	if err != nil {
 		Fatalf("%v", err)
 	}
-	needCover := flags&ipc.FlagSignal != 0
+	needCover := config.Flags&ipc.FlagSignal != 0
 	dedupCover := true
 	if *flagCoverFile != "" {
-		flags |= ipc.FlagSignal
+		config.Flags |= ipc.FlagSignal
 		needCover = true
 		dedupCover = false
 	}
@@ -75,7 +75,7 @@ func main() {
 		}
 	}
 	if handled["syz_emit_ethernet"] {
-		flags |= ipc.FlagEnableTun
+		config.Flags |= ipc.FlagEnableTun
 	}
 
 	var wg sync.WaitGroup
@@ -89,7 +89,7 @@ func main() {
 		pid := p
 		go func() {
 			defer wg.Done()
-			env, err := ipc.MakeEnv(*flagExecutor, timeout, flags, pid)
+			env, err := ipc.MakeEnv(*flagExecutor, pid, config)
 			if err != nil {
 				Fatalf("failed to create ipc env: %v", err)
 			}
@@ -126,7 +126,7 @@ func main() {
 					if failed {
 						fmt.Printf("BUG: executor-detected bug:\n%s", output)
 					}
-					if flags&ipc.FlagDebug != 0 || err != nil {
+					if config.Flags&ipc.FlagDebug != 0 || err != nil {
 						fmt.Printf("result: failed=%v hanged=%v err=%v\n\n%s", failed, hanged, err, output)
 					}
 					if *flagCoverFile != "" {
diff --git a/tools/syz-stress/stress.go b/tools/syz-stress/stress.go
index 043af44fd..87f016504 100644
--- a/tools/syz-stress/stress.go
+++ b/tools/syz-stress/stress.go
@@ -50,7 +50,7 @@ func main() {
 	prios := prog.CalculatePriorities(corpus)
 	ct := prog.BuildChoiceTable(prios, calls)
 
-	flags, timeout, err := ipc.DefaultFlags()
+	config, err := ipc.DefaultConfig()
 	if err != nil {
 		Fatalf("%v", err)
 	}
@@ -58,7 +58,7 @@ func main() {
 	for pid := 0; pid < *flagProcs; pid++ {
 		pid := pid
 		go func() {
-			env, err := ipc.MakeEnv(*flagExecutor, timeout, flags, pid)
+			env, err := ipc.MakeEnv(*flagExecutor, pid, config)
 			if err != nil {
 				Fatalf("failed to create execution environment: %v", err)
 			}