executor: fix writing of remote coverage

We never reset remote coverage, so if there is one block,
we will write it after every call and multiple times at the end.
It can lead to "too many calls in output" and just writes quadratic
amount of coverage/signal.
Reset remote coverage after writing.

1 files changed, 22 insertions, 2 deletions

diff --git a/pkg/runtest/run_test.go b/pkg/runtest/run_test.go
index 3da87dd6c..0861b7e2b 100644
--- a/pkg/runtest/run_test.go
+++ b/pkg/runtest/run_test.go
@@ -144,6 +144,7 @@ func TestCover(t *testing.T) {
 
 type CoverTest struct {
 	Is64Bit         bool
+	ExtraCoverage   bool
 	Input           []byte
 	MaxSignal       []uint64
 	CoverFilter     []uint64
@@ -356,6 +357,15 @@ func testCover(t *testing.T, target *prog.Target) {
 				0xc0000020, 0xc0000010, 0xc0000001},
 			Signal: []uint64{0xc0001100, 0xc0000140, 0xc0000011, 0xc0000001},
 		},
+		// Extra coverage.
+		{
+			Is64Bit:       true,
+			ExtraCoverage: true,
+			Input:         makeCover64(0xc0dec0dec0000001, 0xc0dec0dec0000010),
+			Flags:         flatrpc.ExecFlagCollectSignal | flatrpc.ExecFlagCollectCover,
+			Cover:         []uint64{0xc0dec0dec0000010, 0xc0dec0dec0000001},
+			Signal:        []uint64{0xc0dec0dec0000011, 0xc0dec0dec0000001},
+		},
 	}
 	executor := csource.BuildExecutor(t, target, "../../")
 	for i, test := range tests {
@@ -382,7 +392,11 @@ func testCover(t *testing.T, target *prog.Target) {
 }
 
 func testCover1(t *testing.T, ctx context.Context, target *prog.Target, test CoverTest, source *queue.PlainQueue) {
-	text := fmt.Sprintf(`syz_inject_cover(&AUTO="%s", AUTO)`, hex.EncodeToString(test.Input))
+	callName := "syz_inject_cover"
+	if test.ExtraCoverage {
+		callName = "syz_inject_remote_cover"
+	}
+	text := fmt.Sprintf(`%s(&AUTO="%s", AUTO)`, callName, hex.EncodeToString(test.Input))
 	p, err := target.Deserialize([]byte(text), prog.Strict)
 	if err != nil {
 		t.Fatal(err)
@@ -390,7 +404,7 @@ func testCover1(t *testing.T, ctx context.Context, target *prog.Target, test Cov
 	req := &queue.Request{
 		Prog: p,
 		ExecOpts: flatrpc.ExecOpts{
-			EnvFlags:  flatrpc.ExecEnvSignal | flatrpc.ExecEnvSandboxNone,
+			EnvFlags:  flatrpc.ExecEnvSignal | flatrpc.ExecEnvExtraCover | flatrpc.ExecEnvSandboxNone,
 			ExecFlags: test.Flags,
 		},
 	}
@@ -403,6 +417,12 @@ func testCover1(t *testing.T, ctx context.Context, target *prog.Target, test Cov
 		t.Fatalf("program execution failed: status=%v err=%v\n%s", res.Status, res.Err, res.Output)
 	}
 	call := res.Info.Calls[0]
+	if test.ExtraCoverage {
+		call = res.Info.Extra
+		if call == nil {
+			t.Fatalf("got no extra coverage info")
+		}
+	}
 	if test.Cover == nil {
 		test.Cover = []uint64{}
 	}