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While using a TFDConnection (FireDAC) our application leaks memory after the DB connection is lost. The size of the leaks is directly related to how many TFDQuery instances have been instantiated. Please advise how to resolve these relatively massive leaks. Incidentally this is running against a DB2 database

The patch below suggests fixes for 7 memory leaks in OverbyteIcsWSocket.pas. They surfaced after the OverbyteIcsSslWebServ.dpr sample project was linked against YuOpenSSL. A total of > 10k memory allocations reported not freed, adding up to > 500k bytes of leaked memory. The leaks were easy to spot because YuOpenSSL does not use the OpenSSL DLLs but compiles all OpenSSL code into the application binary. As a side effect, YuOpenSSL uses the Delphi memory manager and by default allows memory trackers to see OpenSSL memory allocations. Otherwise this does normally not happen when the OpenSSL DLLs employ their own memory management. The leaks then sum up in the DLLs' memory space, and out of sight of Delphi's memory trackers. For anyone who would like to test their ICS applications for memory leaks with YuOpenSSL, here is the link: https://www.yunqa.de/delphi/products/openssl/index Index: OverbyteIcsWSocket.pas =================================================================== --- OverbyteIcsWSocket.pas (revision 1492) +++ OverbyteIcsWSocket.pas (working copy) @@ -13933,7 +13933,8 @@ for I := 0 to Result - 1 do begin P := f_OPENSSL_sk_value(CertStack, I); if Assigned(P) then { V8.64 sanity test } - Add(f_X509_dup(PX509(P))); + // Add(f_X509_dup(PX509(P))); // ralfjunker fix memory leak. + Add(PX509(P)); // ralfjunker fix memory leak. end; end; @@ -14866,7 +14867,8 @@ OneErr := String(LastOpenSslErrMsg(FALSE)); OneErr := 'Error Cert ' + IntToStr(tot) + ' - ' + OneErr; end; - end; + // end; ralfjunker fix memory leak. + end else f_BIO_free(MemBio); // ralfjunker fix memory leak. // ignore private keys and other stuff if OneErr <> '' then begin @@ -17369,7 +17371,8 @@ procedure TX509Base.FreeAndNilX509Inters; { V8.41 } begin if Assigned(FX509Inters) then begin - f_OPENSSL_sk_free(FX509Inters); + // f_OPENSSL_sk_free(FX509Inters); // ralfjunker fix memory leak. + f_OPENSSL_sk_pop_free(FX509Inters, @f_X509_free); // ralfjunker fix memory leak. FX509Inters := nil; end; end; @@ -18334,7 +18337,10 @@ // pending, search stack for server certificate, might not be first { first in stack is server certificate } - SetX509(PX509(f_OPENSSL_sk_delete(MyStack, 0))); + // SetX509(PX509(f_OPENSSL_sk_delete(MyStack, 0))); // ralfjunker fix memory leak. + x := PX509(f_OPENSSL_sk_delete(MyStack, 0)); // ralfjunker fix memory leak. + SetX509(x); // ralfjunker fix memory leak. + f_X509_free(x); // ralfjunker fix memory leak. { remaineder are intermediates } if (TotInfo > 1) and (IncludeInters > croNo) then begin @@ -19394,7 +19400,8 @@ begin result := '' ; if not Assigned(X509) then Exit; - pubkey := f_X509_get_pubkey(X509); + // pubkey := f_X509_get_pubkey(X509); // ralfjunker fix memory leak. + pubkey := f_X509_get0_pubkey(X509); // ralfjunker fix memory leak. Result := GetKeyDesc(pubkey); end; @@ -19500,17 +19507,27 @@ {* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} procedure TX509Base.LoadIntersFromPemFile(const FileName: String); { V8.41 } +var // ralfjunker fix memory leak. + x: PStack; // ralfjunker fix memory leak. begin InitializeSsl; - SetX509Inters(IcsSslLoadStackFromInfoFile(FileName, emCert)); + // SetX509Inters(IcsSslLoadStackFromInfoFile(FileName, emCert)); // ralfjunker fix memory leak. + x := IcsSslLoadStackFromInfoFile(FileName, emCert); // ralfjunker fix memory leak. + SetX509Inters(x); // ralfjunker fix memory leak. + f_OPENSSL_sk_free(x); // ralfjunker fix memory leak. end; {* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *} procedure TX509Base.LoadIntersFromString(const Value: String); { V8.41 } +var // ralfjunker fix memory leak. + x: PStack; // ralfjunker fix memory leak. begin InitializeSsl; - SetX509Inters(IcsSslLoadStackFromInfoString(Value, emCert)); + // SetX509Inters(IcsSslLoadStackFromInfoString(Value, emCert)); // ralfjunker fix memory leak. + x := IcsSslLoadStackFromInfoString(Value, emCert); // ralfjunker fix memory leak. + SetX509Inters(x); // ralfjunker fix memory leak. + f_OPENSSL_sk_free(x); // ralfjunker fix memory leak. end;

OverbyteIcsWSocket.pas has at least one small memory leak. In line 17009 (SVN 1464), an X509Obj is duplicated before its is added to the list. However, TX509Base.Create() duplicates the duplication once more before TX509List.Add() stores it to the list. The first duplicated object is never freed, resulting in the leak. This is the line in question: CertList.Add(f_X509_dup(f_X509_OBJECT_get0_X509 (MyX509Obj))); The fix is to remove f_X509_dup(), so the line looks like this: CertList.Add(f_X509_OBJECT_get0_X509 (MyX509Obj)); Code analysis suggests that a similar leak is present in line 15012, but I have not been able to trigger this code running one of the Sample projects: Cert.AddToInters(f_X509_dup(f_X509_OBJECT_get0_X509 (MyX509Obj))); Ralf