пятница, 7 сентября 2018 г.

apisetschema.dll from windows 10 build 1774

new modules was added since 15025
  • win-containers-cmclient
  • win-core-backgroundtask
  • win-core-com-private
  • win-core-file-fromapp
  • win-core-pcw
  • win-core-state-helpers
  • win-gaming-deviceinformation
  • win-security-isolationapi
  • win-security-isolationpolicy
  • win-shcore-taskpool
  • win-wsl-api
  • win-appcompat-aeinv
  • win-hostactivitymanager-hostidstore
  • win-hyperv-hgs
  • win-hyperv-hvemulation
  • win-hyperv-hvplatform
  • win-hyperv-compute
  • win-networking-teredo
  • win-rtcore-ntuser-controllernavigation
  • win-security-authz-helper
  • win-security-catalog-database
  • ms-win-security-cfl
  • win-security-ngc-local
  • win-security-vaultcds
  • win-session-candidateaccountmgr

среда, 8 августа 2018 г.

bug in wtsapi32!WTSFreeMemoryExA

prototype
BOOL WTSFreeMemoryExA(
  WTS_TYPE_CLASS WTSTypeClass,
  PVOID          pMemory,
  ULONG          NumberOfEntries
);

WTS_TYPE_CLASS declared in WtsApi32.h as
enum _WTS_TYPE_CLASS {
  WTSTypeProcessInfoLevel0 = 0x0,
  WTSTypeProcessInfoLevel1 = 0x1,
  WTSTypeSessionInfoLevel1 = 0x2,
};

ok, check in disasm what happens:
WTSFreeMemoryExA proc near 
  push    rbx
  sub     rsp, 20h
  xor     ebx, ebx
  cmp     ecx, ebx
  jl      short loc_7FF70582EC2
  cmp     ecx, 1 ; whut ?
  jg      short loc_7FF70582EC2
  call    WTSFreeMemoryExW
  mov     ebx, eax
  jmp     short loc_7FF70582ECD

loc_7FF70582EC2: 
  mov     ecx, 87         ; dwErrCode - ERROR_INVALID_PARAMETER
  call    cs:__imp_SetLastError 

as you can see you cannot pass WTSTypeSessionInfoLevel1 to function WTSFreeMemoryExA - it gives error ERROR_INVALID_PARAMETER. As dirty workaround you can use WTSFreeMemoryExW - it has correct checking of WTSTypeClass. btw this lead to memory leaks and known at least since 2013

пятница, 29 июня 2018 г.

interesting case of memory leak

after three weeks of work service osqueryd.exe consumed about 150 mb of memory. so I made full memory dump with process explorer and run !heap -l in windbg
298991 string in log ! lets write quick and ditry perl script to calculate sizes of leaked blocks:
my $state = 0;
my($str, %dict, $size);
while( $str = <> )
{
  chomp $str;
  last if ( $str eq '' );
  if ( ! $state )
  {
    $state = 1 if ( $str =~ /^-----/ );
    next;
  }
  $str = substr($str, 72, 10);
  $str =~ s/^\s+//g;
  $str =~ s/\s+$//g;
  $size = hex($str);
  next if ( !$size );
  $dict{$size} += 1;
}

# dump results
my $iter;
foreach $iter ( sort { $dict{$b} <=> $dict{$a} } keys %dict )
{
  printf("%X %d\n", $iter, $dict{$iter});
}
results are encouraging:

среда, 17 января 2018 г.

wincheck rc8.60

download
mirror
Changelog:
  • add some support of meltdown patched kernels. It seems that Microsoft backported from w10 InterruptObject to KPRCB on windows 8.1. so all offsets below this field were shifted downward and previous version of wincheck produced BSODs
  • add dumping of SYSTEM_KERNEL_VA_SHADOW_INFORMATION
  • add support of windows 10 build 17063
  • add lots of new WNF IDs names from ADK version 10.1.16299