internal/trace/v2: reject events for goroutines with unknown states

Change-Id: Ifc472ed4cf0433d06f43559930ac80df23656a6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/555496
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

diff --git a/src/internal/trace/v2/order.go b/src/internal/trace/v2/order.go
index 2cc7f26d29f4c9ed3dec5324cd09ec643231c776..24da41a35e1951918c74f0ae4e130a49f3bc1314 100644 (file)
--- a/src/internal/trace/v2/order.go
+++ b/src/internal/trace/v2/order.go
@@ -649,7 +649,11 @@ func (o *ordering) advance(ev *baseEvent, evt *evTable, m ThreadID, gen uint64)
                if !ok {
                        return curCtx, false, fmt.Errorf("invalid string ID %v for %v event", nameID, typ)
                }
-               if err := o.gStates[curCtx.G].beginRegion(userRegion{tid, name}); err != nil {
+               gState, ok := o.gStates[curCtx.G]
+               if !ok {
+                       return curCtx, false, fmt.Errorf("encountered EvUserRegionBegin without known state for current goroutine %d", curCtx.G)
+               }
+               if err := gState.beginRegion(userRegion{tid, name}); err != nil {
                        return curCtx, false, err
                }
                return curCtx, true, nil
@@ -663,7 +667,11 @@ func (o *ordering) advance(ev *baseEvent, evt *evTable, m ThreadID, gen uint64)
                if !ok {
                        return curCtx, false, fmt.Errorf("invalid string ID %v for %v event", nameID, typ)
                }
-               if err := o.gStates[curCtx.G].endRegion(userRegion{tid, name}); err != nil {
+               gState, ok := o.gStates[curCtx.G]
+               if !ok {
+                       return curCtx, false, fmt.Errorf("encountered EvUserRegionEnd without known state for current goroutine %d", curCtx.G)
+               }
+               if err := gState.endRegion(userRegion{tid, name}); err != nil {
                        return curCtx, false, err
                }
                return curCtx, true, nil
@@ -792,7 +800,11 @@ func (o *ordering) advance(ev *baseEvent, evt *evTable, m ThreadID, gen uint64)
                if typ == go122.EvSTWBegin {
                        desc = stringID(ev.args[0])
                }
-               if err := o.gStates[curCtx.G].beginRange(makeRangeType(typ, desc)); err != nil {
+               gState, ok := o.gStates[curCtx.G]
+               if !ok {
+                       return curCtx, false, fmt.Errorf("encountered event of type %d without known state for current goroutine %d", typ, curCtx.G)
+               }
+               if err := gState.beginRange(makeRangeType(typ, desc)); err != nil {
                        return curCtx, false, err
                }
                return curCtx, true, nil
@@ -813,7 +825,11 @@ func (o *ordering) advance(ev *baseEvent, evt *evTable, m ThreadID, gen uint64)
                if err := validateCtx(curCtx, event.UserGoReqs); err != nil {
                        return curCtx, false, err
                }
-               desc, err := o.gStates[curCtx.G].endRange(typ)
+               gState, ok := o.gStates[curCtx.G]
+               if !ok {
+                       return curCtx, false, fmt.Errorf("encountered event of type %d without known state for current goroutine %d", typ, curCtx.G)
+               }
+               desc, err := gState.endRange(typ)
                if err != nil {
                        return curCtx, false, err
                }

diff --git a/src/internal/trace/v2/testdata/fuzz/FuzzReader/4d9ddc909984e871 b/src/internal/trace/v2/testdata/fuzz/FuzzReader/4d9ddc909984e871
new file mode 100644 (file)
index 0000000..040b2a4
--- /dev/null
+++ b/src/internal/trace/v2/testdata/fuzz/FuzzReader/4d9ddc909984e871
@@ -0,0 +1,2 @@
+go test fuzz v1
+[]byte("go 1.22 trace\x00\x00\x00\x01\x0100\x11\r\xa700\x01\x19000\x02$000000\x01\x0100\x05\b0000\x01\x0110\x11\r\xa700\x01\x19 00\x02\x110 0000")

diff --git a/src/internal/trace/v2/testdata/fuzz/FuzzReader/9d6ee7d3ddf8d566 b/src/internal/trace/v2/testdata/fuzz/FuzzReader/9d6ee7d3ddf8d566
new file mode 100644 (file)
index 0000000..5677261
--- /dev/null
+++ b/src/internal/trace/v2/testdata/fuzz/FuzzReader/9d6ee7d3ddf8d566
@@ -0,0 +1,2 @@
+go test fuzz v1
+[]byte("go 1.22 trace\x00\x00\x00\x01\x0100\x11\r\xa700\x01\x19000\x02#000000\x01\x0100\x05\b0000\x01\x0110\x11\r\xa700\x01\x19 00\x02\x110 0000")