rpc: /broadcast_evidence nil evidence check (#5109)

rpc/client/evidence_test.go

@@ -222,3 +222,10 @@ func TestBroadcastEvidence_ConflictingHeadersEvidence(t *testing.T) {
 		assert.Equal(t, ev.Hash(), result.Hash, "expected result hash to match evidence hash")
 	}
 }
+
+func TestBroadcastEmptyEvidence(t *testing.T) {
+	for _, c := range GetClients() {
+		_, err := c.BroadcastEvidence(nil)
+		assert.Error(t, err)
+	}
+}

rpc/core/evidence.go

@@ -1,6 +1,7 @@
 package core
 
 import (
+	"errors"
 	"fmt"
 
 	ctypes "github.com/tendermint/tendermint/rpc/core/types"
@@ -11,6 +12,10 @@ import (
 // BroadcastEvidence broadcasts evidence of the misbehavior.
 // More: https://docs.tendermint.com/master/rpc/#/Info/broadcast_evidence
 func BroadcastEvidence(ctx *rpctypes.Context, ev types.Evidence) (*ctypes.ResultBroadcastEvidence, error) {
+	if ev == nil {
+		return nil, errors.New("no evidence was provided")
+	}
+
 	if err := ev.ValidateBasic(); err != nil {
 		return nil, fmt.Errorf("evidence.ValidateBasic failed: %w", err)
 	}