mORMot Open Source

ThepSamart

Member

Registered: 2022-10-19

Posts: 3

Access violations on ToDataset using mORMot2-2.0.4148

I got access violation using latest release mORMot2-2.0.4148.

An exception are in TSqlDBProxyStatementRandomAccess.Create() and TSqlDBStatementWithParamsAndColumns.Create().
TSqlDBProxyStatementRandomAccess.Create() passed aConnection as nil to TSqlDBStatementWithParamsAndColumns.Create(), so testing for aConnection will raise error.

This is not occurred in previous release mORMot2-2.0.3780.

code: Reproducible Example

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,661

Website

Re: Access violations on ToDataset using mORMot2-2.0.4148

(which compiler are you using?)

The whole memory release pattern seems pretty unsafe.
Calling z_conn.Free is too soon for sure.
Perhaps missing i_rows := nil and perhaps also TAutoFree not possible ?
See as reference https://synopse.info/files/html/Synopse … l#TITL_195

ThepSamart

Member

Registered: 2022-10-19

Posts: 3

Re: Access violations on ToDataset using mORMot2-2.0.4148

Sorry for the code provided, it's for testing only.

I use Delphi 10.2.3 Tokyo.

Could you examine code in mormot.db.proxy or trace back thru ToDataset() function.

constructor TSqlDBProxyStatementRandomAccess.Create(Data: PByte; DataLen: integer;
  DataRowPosition: PCardinalDynArray; IgnoreColumnDataSize: boolean);
var
  i, f: PtrInt;
  reader: PByte;
begin
  fLastGotoRow := -1;
  inherited Create(nil);
  InternalHeaderProcess(Data, DataLen);

The constructor inherited Create(nil) that passed thru

constructor TSqlDBStatementWithParamsAndColumns.Create(
  aConnection: TSqlDBConnection);

so aConnection was passed as nil. This could be the cause.

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,661

Website

Re: Access violations on ToDataset using mORMot2-2.0.4148

The culprit is clearly https://github.com/synopse/mORMot2/comm … 20cd7a5c62

Should be fixed by https://github.com/synopse/mORMot2/commit/7d1d8f62

Sorry for the issue.

ThepSamart

Member

Registered: 2022-10-19

Posts: 3

Re: Access violations on ToDataset using mORMot2-2.0.4148

Hi,

The latest release on GitHub (commit 4222) is working as expected.

Thank You and Regards.