conn: fix lost connection when insert from select panic cause by out …

…of memory quota (pingcap#12090)

executor/adapter.go

@@ -43,6 +43,7 @@ import (
 	"github.com/pingcap/tidb/store/tikv"
 	"github.com/pingcap/tidb/util/chunk"
 	"github.com/pingcap/tidb/util/logutil"
+	"github.com/pingcap/tidb/util/memory"
 	"github.com/pingcap/tidb/util/sqlexec"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
@@ -207,6 +208,18 @@ func (a *ExecStmt) RebuildPlan(ctx context.Context) (int64, error) {
 // like the INSERT, UPDATE statements, it executes in this function, if the Executor returns
 // result, execution is done after this function returns, in the returned sqlexec.RecordSet Next method.
 func (a *ExecStmt) Exec(ctx context.Context) (_ sqlexec.RecordSet, err error) {
+	defer func() {
+		r := recover()
+		if r == nil {
+			return
+		}
+		if str, ok := r.(string); !ok || !strings.HasPrefix(str, memory.PanicMemoryExceed) {
+			panic(r)
+		}
+		err = errors.Errorf("%v", r)
+		logutil.Logger(ctx).Error("execute sql panic", zap.String("sql", a.Text), zap.Stack("stack"))
+	}()
+
 	sctx := a.Ctx
 	if _, ok := a.Plan.(*plannercore.Analyze); ok && sctx.GetSessionVars().InRestrictedSQL {
 		oriStats, _ := sctx.GetSessionVars().GetSystemVar(variable.TiDBBuildStatsConcurrency)

executor/executor_test.go

@@ -4184,6 +4184,16 @@ func (s *testSuite) TestOOMPanicAction(c *C) {
 	err := tk.QueryToErr("select sum(b) from t group by a;")
 	c.Assert(err, NotNil)
 	c.Assert(err.Error(), Matches, "Out Of Memory Quota!.*")
+
+	// Test insert from select oom panic.
+	tk.MustExec("drop table if exists t,t1")
+	tk.MustExec("create table t (a bigint);")
+	tk.MustExec("create table t1 (a bigint);")
+	tk.MustExec("insert into t1 values (1),(2),(3),(4),(5);")
+	tk.MustExec("set @@tidb_mem_quota_query=200;")
+	_, err = tk.Exec("insert into t select a from t1 order by a desc;")
+	c.Assert(err, NotNil)
+	c.Assert(err.Error(), Matches, "Out Of Memory Quota!.*")
 }
 
 type oomCapturer struct {