Reject overflowing metric timestamp offsets

test/metricsviz/metricsviz.go

@@ -693,7 +693,8 @@ func Parse(logs string, hasPrefix bool) (*Data, error) {
 		if len(tabularData) != len(header)+1 {
 			return nil, fmt.Errorf("invalid data line: %q with %d components which does not match header which has %d components. This is likely due to a log buffer overrun or similar issue causing the line to be cut off; please configure the container or the runtime to allow higher logging volume", line, len(tabularData), len(header))
 		}
-		offsetNanos, err := strconv.ParseUint(tabularData[0], 10, 64)
+		// Offsets must fit in time.Duration without becoming negative.
+		offsetNanos, err := strconv.ParseUint(tabularData[0], 10, 63)
 		if err != nil {
 			return nil, fmt.Errorf("invalid data line: %q (bad timestamp: %w)", line, err)
 		}

test/metricsviz/metricsviz_cli/metricsviz_cli_test.go

@@ -17,11 +17,14 @@ package metricsviz_cli_test
 
 import (
 	"context"
+	"errors"
 	"fmt"
+	"math"
 	"math/rand/v2"
 	"os"
 	"os/exec"
 	"path"
+	"strconv"
 	"strings"
 	"testing"
 	"time"
@@ -31,6 +34,26 @@ import (
 	"gvisor.dev/gvisor/test/metricsviz"
 )
 
+func TestTimestampOffset(t *testing.T) {
+	for _, tc := range []struct {
+		offset  uint64
+		wantErr error
+	}{
+		{offset: 0},
+		{offset: math.MaxInt64},
+		{offset: math.MaxInt64 + 1, wantErr: strconv.ErrRange},
+		{offset: math.MaxUint64, wantErr: strconv.ErrRange},
+	} {
+		t.Run(strconv.FormatUint(tc.offset, 10), func(t *testing.T) {
+			logs := fmt.Sprintf("%s/counter\t{}\n%s1\n%s\t/counter\n%d\t1\n",
+				metric.MetricsMetaIndicator, metric.MetricsStartTimeIndicator, metric.TimeColumn, tc.offset)
+			if _, err := metricsviz.Parse(logs, false); !errors.Is(err, tc.wantErr) {
+				t.Fatalf("Parse() error = %v, want %v", err, tc.wantErr)
+			}
+		})
+	}
+}
+
 func TestMetricsvizCLI(t *testing.T) {
 	ctx := context.Background()
 	cliPath, err := testutil.FindFile("test/metricsviz/metricsviz_cli/metricsviz_cli")