Merge pull request #67728 from cockroachdb/blathers/backport-release-…

…21.1-67707 release-21.1: kv: fix aliasing bug in leaseHistory.get
cockroachdb · Aug 3, 2021 · 391ec3d · 391ec3d
2 parents f395e17 + 9cd39d3
commit 391ec3d
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Showing 2 changed files with 6 additions and 1 deletion.
diff --git a/pkg/kv/kvserver/lease_history.go b/pkg/kv/kvserver/lease_history.go
@@ -58,7 +58,7 @@ func (lh *leaseHistory) get() []roachpb.Lease {
 	if len(lh.history) < leaseHistoryMaxEntries || lh.index == 0 {
 		result := make([]roachpb.Lease, len(lh.history))
 		copy(result, lh.history)
-		return lh.history
+		return result
 	}
 	first := lh.history[lh.index:]
 	second := lh.history[:lh.index]

diff --git a/pkg/kv/kvserver/lease_history_test.go b/pkg/kv/kvserver/lease_history_test.go
@@ -16,6 +16,7 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/roachpb"
 	"github.com/cockroachdb/cockroach/pkg/util/leaktest"
 	"github.com/cockroachdb/cockroach/pkg/util/log"
+	"github.com/stretchr/testify/require"
 )
 
 func TestLeaseHistory(t *testing.T) {
@@ -35,6 +36,9 @@ func TestLeaseHistory(t *testing.T) {
 			if e, a := int64(i-1), leases[len(leases)-1].Epoch; e != a {
 				t.Errorf("%d: expected newest lease to have epoch of %d , actual %d:\n%+v", i, e, a, leases)
 			}
+			require.NotSame(t, &history.history[0], &leases[0], "expected slice copy")
+		} else {
+			require.Nil(t, leases)
 		}
 
 		history.add(roachpb.Lease{
@@ -54,6 +58,7 @@ func TestLeaseHistory(t *testing.T) {
 		if e, a := int64(i+leaseHistoryMaxEntries-1), leases[leaseHistoryMaxEntries-1].Epoch; e != a {
 			t.Errorf("%d: expected newest lease to have epoch of %d , actual %d:\n%+v", i, e, a, leases)
 		}
+		require.NotSame(t, &history.history[0], &leases[0], "expected slice copy")
 
 		history.add(roachpb.Lease{
 			Epoch: int64(i + leaseHistoryMaxEntries),