Как найти объекты / дескрипторы в кадре стека вызовов ожидает "WaitForMultipleObjects"? - PullRequest
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Как найти объекты / дескрипторы в кадре стека вызовов ожидает "WaitForMultipleObjects"?

0 голосов
/ 26 августа 2018

  1. В кадре 2, kernel32! WaitForMultipleObjects + 0x19, вызов Win32 API ожидает нескольких объектов / дескрипторов.

  2. В Windbg, как мы можем определить эти маркеры для этого конкретного кадра? 

        0:012> k
     # ChildEBP RetAddr   00 093ffba0 7510285f ntdll!NtWaitForMultipleObjects+0xc
    01 093ffd2c 76f89188 KERNELBASE!WaitForMultipleObjectsEx+0xcc
    02 093ffd48 61006516 kernel32!WaitForMultipleObjects+0x19
    03 093ffd80 610065b0 mshtml!CRenderThread::WaitForWork+0x82
    04 093ffdc4 61130503 mshtml!CRenderThread::RenderThread+0x2b0
    05 093ffdd4 6d363a31 mshtml!CRenderThread::StaticRenderThreadProc+0x23
    06 (Inline) -------- IEShims!NS_CreateThread::ThreadProc+0x86
    07 093ffe0c 76f8919f IEShims!NS_CreateThread::DesktopIE_ThreadProc+0x94
    08 093ffe18 776ead8f kernel32!BaseThreadInitThunk+0xe
    09 093ffe60 776ead5a ntdll!__RtlUserThreadStart+0x2f
    0a 093ffe70 00000000 ntdll!_RtlUserThreadStart+0x1b

    **//Arguments passed in function call : kernel32!WaitForMultipleObjects+0x19**
    0:012> dd 093ffd48
    093ffd48  093ffd80 61006516 **00000002 093ffd6c**
    093ffd58  **00000000 ffffffff** 00000000 00000000
    093ffd68  05ef6078 00000778 000007c8 00000002
    093ffd78  ffffffff 093ffdc4 093ffdc4 610065b0
    093ffd88  093ffde0 00000000 00000006 61015990
    093ffd98  1b541170 00000000 00000000 00000000
    093ffda8  00000000 00000000 00000000 1b541170
    093ffdb8  00000000 05ef6078 003ffdd4 093ffdd4

1 Ответ

0 голосов
/ 26 августа 2018

выход k 

kd> $$ 00adfb88 7755fe39 ntdll!NtWaitForMultipleObjects+0xc (FPO: [5,0,0])

бросает мечи на ebp 

kd> dd 00adfb88 l 8
00adfb88  77576a44 7755fe39 00000010 00412ca8
00adfb98  00000001 00000001 00000000 77cc0c57

kd> $$ ebp + 8 = первый аргумент = 10
kd> $$ ebp + c = второй аргумент = * к ручкам 412ca8
kd> $$ ручки 

kd> dd 412ca8 l10
00412ca8  000000f4 000000f0 0000069c 00000900
00412cb8  00000464 000007d0 0000081c 00000828
00412cc8  000006d8 00000640 00000634 0000056c
00412cd8  0000037c 00000460 00000654 00000100

скрипт, подобный этому, может взять вас за ручку 

kd> .foreach /pS 1 /ps 1 (place { dd /c 1 412ca8 l10 } ) { !handle place 2}

выход 

PROCESS 86f6a6c8  SessionId: 1  Cid: 0b78    Peb: 7ffd8000  ParentCid: 0b6c
    DirBase: 7e26c4c0  ObjectTable: b908ef00  HandleCount: 1079.
    Image: explorer.exe

Handle table at b908ef00 with 1079 entries in use

00f4: Object: 86945a90  GrantedAccess: 001f0003 Entry: b90951e8
Object: 86945a90  Type: (84eaf350) Timer
    ObjectHeader: 86945a78 (new version)
        HandleCount: 1 PointerCount: 2

00f0: Object: 869416c0  GrantedAccess: 00100002 Entry: b90951e0
Object: 869416c0  Type: (84eaf350) Timer
    ObjectHeader: 869416a8 (new version)
        HandleCount: 1 PointerCount: 2

069c: Object: 86a12388  GrantedAccess: 00100004 Entry: b9095d38
Object: 86a12388  Type: (84ed06b8) WmiGuid
    ObjectHeader: 86a12370 (new version)
        HandleCount: 1 PointerCount: 2

0900: Object: 869b2d38  GrantedAccess: 001f0003 Entry: b8601200
Object: 869b2d38  Type: (84eb0978) Event
    ObjectHeader: 869b2d20 (new version)
        HandleCount: 1 PointerCount: 2

0464: Object: 85540d00  GrantedAccess: 001f0003 Entry: b90958c8
Object: 85540d00  Type: (84eb0978) Event
    ObjectHeader: 85540ce8 (new version)
        HandleCount: 1 PointerCount: 3

07d0: Object: 8552a480  GrantedAccess: 001f0003 Entry: b9095fa0
Object: 8552a480  Type: (84eb0978) Event
    ObjectHeader: 8552a468 (new version)
        HandleCount: 1 PointerCount: 4

081c: Object: 85cdde78  GrantedAccess: 001f0003 Entry: b8601038
Object: 85cdde78  Type: (84eb0978) Event
    ObjectHeader: 85cdde60 (new version)
        HandleCount: 1 PointerCount: 3
        Directory Object: 98a802a8  Name: PRS_EXTERNAL_CHECK_CHANGED_NOTIFY

0828: Object: 86c4c938  GrantedAccess: 001f0003 Entry: b8601050
Object: 86c4c938  Type: (84eb0978) Event
    ObjectHeader: 86c4c920 (new version)
        HandleCount: 2 PointerCount: 5
        Directory Object: 98a802a8  Name: {43a2b8d7-6fed-4c18-bd36-b4630d61afb5}

06d8: Object: 86d014d0  GrantedAccess: 001f0003 Entry: b9095db0
Object: 86d014d0  Type: (84eb0978) Event
    ObjectHeader: 86d014b8 (new version)
        HandleCount: 1 PointerCount: 2

0640: Object: 85ce4380  GrantedAccess: 001f0003 Entry: b9095c80
Object: 85ce4380  Type: (84eb0978) Event
    ObjectHeader: 85ce4368 (new version)
        HandleCount: 1 PointerCount: 2

0634: Object: 86f17e20  GrantedAccess: 001f0003 Entry: b9095c68
Object: 86f17e20  Type: (84eb0978) Event
    ObjectHeader: 86f17e08 (new version)
        HandleCount: 1 PointerCount: 2

056c: Object: 85ce7750  GrantedAccess: 001f0003 Entry: b9095ad8
Object: 85ce7750  Type: (84eb0978) Event
    ObjectHeader: 85ce7738 (new version)
        HandleCount: 1 PointerCount: 2

037c: Object: 86bbcae8  GrantedAccess: 001f0003 Entry: b90956f8
Object: 86bbcae8  Type: (84eb0978) Event
    ObjectHeader: 86bbcad0 (new version)
        HandleCount: 2 PointerCount: 3

0460: Object: 86cdab88  GrantedAccess: 001f0003 Entry: b90958c0
Object: 86cdab88  Type: (84eb0978) Event
    ObjectHeader: 86cdab70 (new version)
        HandleCount: 1 PointerCount: 2

0654: Object: 85ce6838  GrantedAccess: 001f0003 Entry: b9095ca8
Object: 85ce6838  Type: (84eb0978) Event
    ObjectHeader: 85ce6820 (new version)
        HandleCount: 1 PointerCount: 2

0100: Object: 865bb170  GrantedAccess: 00100002 Entry: b9095200
Object: 865bb170  Type: (84eaf350) Timer
    ObjectHeader: 865bb158 (new version)
        HandleCount: 1 PointerCount: 2


kd>
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