storage: fix bug #10027 in iterators' Seek method

Signed-off-by: beorn7 <beorn@grafana.com>

storage/remote/codec.go

@@ -360,6 +360,9 @@ func (c *concreteSeriesIterator) Seek(t int64) bool {
 	if c.cur == -1 {
 		c.cur = 0
 	}
+	if c.cur >= len(c.series.samples) {
+		return false
+	}
 	// No-op check.
 	if s := c.series.samples[c.cur]; s.Timestamp >= t {
 		return true

storage/series.go

@@ -99,6 +99,9 @@ func (it *listSeriesIterator) Seek(t int64) bool {
 	if it.idx == -1 {
 		it.idx = 0
 	}
+	if it.idx >= it.samples.Len() {
+		return false
+	}
 	// No-op check.
 	if s := it.samples.Get(it.idx); s.T() >= t {
 		return true

tsdb/tsdbutil/buffer_test.go

@@ -159,6 +159,9 @@ func (it *listSeriesIterator) Seek(t int64) bool {
 	if it.idx == -1 {
 		it.idx = 0
 	}
+	if it.idx >= len(it.list) {
+		return false
+	}
 	// No-op check.
 	if s := it.list[it.idx]; s.T() >= t {
 		return true