From 997a5ace91a1546e0d8c65e699dce605edaa4265 Mon Sep 17 00:00:00 2001
From: Nick Cabatoff <ncabatoff@hashicorp.com>
Date: Fri, 26 Nov 2021 08:38:39 -0500
Subject: [PATCH] Prevent raft transactions from containing overlarge keys.
 (#13286)

---
 changelog/13286.txt        |  3 +++
 physical/raft/raft.go      |  3 +++
 physical/raft/raft_test.go | 39 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 45 insertions(+)
 create mode 100644 changelog/13286.txt

diff --git a/changelog/13286.txt b/changelog/13286.txt
new file mode 100644
index 000000000..9d39be65f
--- /dev/null
+++ b/changelog/13286.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+storage/raft: Fix a panic when trying to store a key > 32KB in a transaction.
+```
diff --git a/physical/raft/raft.go b/physical/raft/raft.go
index 8d3621862..f88d66c5b 100644
--- a/physical/raft/raft.go
+++ b/physical/raft/raft.go
@@ -1352,6 +1352,9 @@ func (b *RaftBackend) Transaction(ctx context.Context, txns []*physical.TxnEntry
 		op := &LogOperation{}
 		switch txn.Operation {
 		case physical.PutOperation:
+			if len(txn.Entry.Key) > bolt.MaxKeySize {
+				return fmt.Errorf("%s, max key size for integrated storage is %d", physical.ErrKeyTooLarge, bolt.MaxKeySize)
+			}
 			op.OpType = putOp
 			op.Key = txn.Entry.Key
 			op.Value = txn.Entry.Value
diff --git a/physical/raft/raft_test.go b/physical/raft/raft_test.go
index f6211d0b7..258d23bc6 100644
--- a/physical/raft/raft_test.go
+++ b/physical/raft/raft_test.go
@@ -280,6 +280,45 @@ func TestRaft_Backend_LargeValue(t *testing.T) {
 	}
 }
 
+func TestRaft_TransactionalBackend_LargeKey(t *testing.T) {
+	b, dir := getRaft(t, true, true)
+	defer os.RemoveAll(dir)
+
+	value := make([]byte, defaultMaxEntrySize+1)
+	rand.Read(value)
+
+	key, err := base62.Random(bolt.MaxKeySize + 1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	txns := []*physical.TxnEntry{
+		{
+			Operation: physical.PutOperation,
+			Entry: &physical.Entry{
+				Key:   key,
+				Value: []byte(key),
+			},
+		},
+	}
+
+	err = b.Transaction(context.Background(), txns)
+	if err == nil {
+		t.Fatal("expected error for transactions")
+	}
+
+	if !strings.Contains(err.Error(), physical.ErrKeyTooLarge) {
+		t.Fatalf("expected %q, got %v", physical.ErrValueTooLarge, err)
+	}
+
+	out, err := b.Get(context.Background(), txns[0].Entry.Key)
+	if err != nil {
+		t.Fatalf("unexpected error after failed put: %v", err)
+	}
+	if out != nil {
+		t.Fatal("expected response entry to be nil after a failed put")
+	}
+}
+
 func TestRaft_TransactionalBackend_LargeValue(t *testing.T) {
 	b, dir := getRaft(t, true, true)
 	defer os.RemoveAll(dir)