CSAM.cpp@ 1995

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1	/* $Id: CSAM.cpp 1995 2007-04-09 13:33:44Z vboxsync $ */
2	/** @file
3	* CSAM - Guest OS Code Scanning and Analysis Manager
4	*/
5
6	/*
7	* Copyright (C) 2006 InnoTek Systemberatung GmbH
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License as published by the Free Software Foundation,
13	* in version 2 as it comes in the "COPYING" file of the VirtualBox OSE
14	* distribution. VirtualBox OSE is distributed in the hope that it will
15	* be useful, but WITHOUT ANY WARRANTY of any kind.
16	*
17	* If you received this file as part of a commercial VirtualBox
18	* distribution, then only the terms of your commercial VirtualBox
19	* license agreement apply instead of the previous paragraph.
20	*/
21
22	/*******************************************************************************
23	* Header Files *
24	*******************************************************************************/
25	#define LOG_GROUP LOG_GROUP_CSAM
26	#include <VBox/cpum.h>
27	#include <VBox/stam.h>
28	#include <VBox/patm.h>
29	#include <VBox/csam.h>
30	#include <VBox/cpumdis.h>
31	#include <VBox/pgm.h>
32	#include <VBox/iom.h>
33	#include <VBox/sup.h>
34	#include <VBox/mm.h>
35	#include <VBox/em.h>
36	#include <VBox/rem.h>
37	#include <VBox/selm.h>
38	#include <VBox/trpm.h>
39	#include <VBox/cfgm.h>
40	#include <VBox/param.h>
41	#include <iprt/avl.h>
42	#include <iprt/asm.h>
43	#include <iprt/thread.h>
44	#include "CSAMInternal.h"
45	#include <VBox/vm.h>
46	#include <VBox/dbg.h>
47	#include <VBox/err.h>
48	#include <VBox/ssm.h>
49	#include <VBox/log.h>
50	#include <iprt/assert.h>
51	#include <iprt/string.h>
52	#include <VBox/dis.h>
53	#include <VBox/disopcode.h>
54	#include <stdlib.h>
55	#include <stdio.h>
56
57
58	/* Enabled by default */
59	#define CSAM_ENABLE
60
61	/* Enable to monitor code pages for self-modifying code. */
62	#define CSAM_MONITOR_CODE_PAGES
63	/* Enable to monitor all scanned pages
64	#define CSAM_MONITOR_CSAM_CODE_PAGES */
65	/* Enable to scan beyond ret instructions.
66	#define CSAM_ANALYSE_BEYOND_RET */
67
68	/*******************************************************************************
69	* Internal Functions *
70	*******************************************************************************/
71	static DECLCALLBACK(int) csamr3Save(PVM pVM, PSSMHANDLE pSSM);
72	static DECLCALLBACK(int) csamr3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version);
73	static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void pvPtr, void pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser);
74	static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr);
75
76	bool csamIsCodeScanned(PVM pVM, RTGCPTR pInstr, PCSAMPAGE *pPage);
77	int csamR3CheckPageRecord(PVM pVM, RTGCPTR pInstr);
78	static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTGCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation = false);
79	static int csamRemovePageRecord(PVM pVM, RTGCPTR GCPtr);
80	static int csamReinit(PVM pVM);
81	static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTGCPTR pInstr, uint32_t opsize, bool fScanned);
82	static int csamAnalyseCodeStream(PVM pVM, GCPTRTYPE(uint8_t ) pInstrGC, GCPTRTYPE(uint8_t ) pCurInstrGC, bool fCode32,
83	PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec);
84
85	/** @todo Temporary for debugging. */
86	static bool fInCSAMCodePageInvalidate = false;
87
88	/*******************************************************************************
89	* Global Variables *
90	*******************************************************************************/
91	#ifdef VBOX_WITH_DEBUGGER
92	static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult);
93	static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult);
94
95	/** Command descriptors. */
96	static const DBGCCMD g_aCmds[] =
97	{
98	/* pszCmd, cArgsMin, cArgsMax, paArgDesc, cArgDescs, pResultDesc, fFlags, pfnHandler pszSyntax, ....pszDescription */
99	{ "csamon", 0, 0, NULL, 0, NULL, 0, csamr3CmdOn, "", "Enable CSAM code scanning." },
100	{ "csamoff", 0, 0, NULL, 0, NULL, 0, csamr3CmdOff, "", "Disable CSAM code scanning." },
101	};
102	#endif
103
104
105	/**
106	* Initializes the CSAM.
107	*
108	* @returns VBox status code.
109	* @param pVM The VM to operate on.
110	*/
111	CSAMR3DECL(int) CSAMR3Init(PVM pVM)
112	{
113	int rc;
114
115	LogFlow(("CSAMR3Init\n"));
116
117	/* Allocate bitmap for the page directory. */
118	rc = MMR3HyperAllocOnceNoRel(pVM, CSAM_PGDIRBMP_CHUNKSsizeof(RTHCPTR), 0, MM_TAG_CSAM, (void *)&pVM->csam.s.pPDBitmapHC);
119	AssertRCReturn(rc, rc);
120	rc = MMR3HyperAllocOnceNoRel(pVM, CSAM_PGDIRBMP_CHUNKSsizeof(RTGCPTR), 0, MM_TAG_CSAM, (void *)&pVM->csam.s.pPDGCBitmapHC);
121	AssertRCReturn(rc, rc);
122	pVM->csam.s.pPDBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDGCBitmapHC);
123	pVM->csam.s.pPDHCBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC);
124
125	rc = csamReinit(pVM);
126	AssertRCReturn(rc, rc);
127
128	/*
129	* Register save and load state notificators.
130	*/
131	rc = SSMR3RegisterInternal(pVM, "CSAM", 0, CSAM_SSM_VERSION, sizeof(pVM->csam.s) + PAGE_SIZE*16,
132	NULL, csamr3Save, NULL,
133	NULL, csamr3Load, NULL);
134	AssertRCReturn(rc, rc);
135
136	STAM_REG(pVM, &pVM->csam.s.StatNrTraps, STAMTYPE_COUNTER, "/CSAM/PageTraps", STAMUNIT_OCCURENCES, "The number of CSAM page traps.");
137	STAM_REG(pVM, &pVM->csam.s.StatDangerousWrite, STAMTYPE_COUNTER, "/CSAM/DangerousWrites", STAMUNIT_OCCURENCES, "The number of dangerous writes that cause a context switch.");
138
139	STAM_REG(pVM, &pVM->csam.s.StatNrPageNPHC, STAMTYPE_COUNTER, "/CSAM/HC/PageNotPresent", STAMUNIT_OCCURENCES, "The number of CSAM pages marked not present.");
140	STAM_REG(pVM, &pVM->csam.s.StatNrPageNPGC, STAMTYPE_COUNTER, "/CSAM/GC/PageNotPresent", STAMUNIT_OCCURENCES, "The number of CSAM pages marked not present.");
141	STAM_REG(pVM, &pVM->csam.s.StatNrPages, STAMTYPE_COUNTER, "/CSAM/PageRec/AddedRW", STAMUNIT_OCCURENCES, "The number of CSAM page records (RW monitoring).");
142	STAM_REG(pVM, &pVM->csam.s.StatNrPagesInv, STAMTYPE_COUNTER, "/CSAM/PageRec/AddedRWI", STAMUNIT_OCCURENCES, "The number of CSAM page records (RW & invalidation monitoring).");
143	STAM_REG(pVM, &pVM->csam.s.StatNrRemovedPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Removed", STAMUNIT_OCCURENCES, "The number of removed CSAM page records.");
144	STAM_REG(pVM, &pVM->csam.s.StatPageRemoveREMFlush,STAMTYPE_COUNTER, "/CSAM/PageRec/Removed/REMFlush", STAMUNIT_OCCURENCES, "The number of removed CSAM page records that caused a REM flush.");
145
146	STAM_REG(pVM, &pVM->csam.s.StatNrPatchPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Patch", STAMUNIT_OCCURENCES, "The number of CSAM patch page records.");
147	STAM_REG(pVM, &pVM->csam.s.StatNrUserPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Ignore/User", STAMUNIT_OCCURENCES, "The number of CSAM user page records (ignored).");
148	STAM_REG(pVM, &pVM->csam.s.StatPagePATM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/PATM", STAMUNIT_OCCURENCES, "The number of PATM page records.");
149	STAM_REG(pVM, &pVM->csam.s.StatPageCSAM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/CSAM", STAMUNIT_OCCURENCES, "The number of CSAM page records.");
150	STAM_REG(pVM, &pVM->csam.s.StatPageREM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/REM", STAMUNIT_OCCURENCES, "The number of REM page records.");
151	STAM_REG(pVM, &pVM->csam.s.StatPageMonitor, STAMTYPE_COUNTER, "/CSAM/PageRec/Monitored", STAMUNIT_OCCURENCES, "The number of monitored pages.");
152
153	STAM_REG(pVM, &pVM->csam.s.StatCodePageModified, STAMTYPE_COUNTER, "/CSAM/Monitor/DirtyPage", STAMUNIT_OCCURENCES, "The number of code page modifications.");
154
155	STAM_REG(pVM, &pVM->csam.s.StatNrFlushes, STAMTYPE_COUNTER, "/CSAM/PageFlushes", STAMUNIT_OCCURENCES, "The number of CSAM page flushes.");
156	STAM_REG(pVM, &pVM->csam.s.StatNrFlushesSkipped, STAMTYPE_COUNTER, "/CSAM/PageFlushesSkipped", STAMUNIT_OCCURENCES, "The number of CSAM page flushes that were skipped.");
157	STAM_REG(pVM, &pVM->csam.s.StatNrKnownPagesHC, STAMTYPE_COUNTER, "/CSAM/HC/KnownPageRecords", STAMUNIT_OCCURENCES, "The number of known CSAM page records.");
158	STAM_REG(pVM, &pVM->csam.s.StatNrKnownPagesGC, STAMTYPE_COUNTER, "/CSAM/GC/KnownPageRecords", STAMUNIT_OCCURENCES, "The number of known CSAM page records.");
159	STAM_REG(pVM, &pVM->csam.s.StatNrInstr, STAMTYPE_COUNTER, "/CSAM/ScannedInstr", STAMUNIT_OCCURENCES, "The number of scanned instructions.");
160	STAM_REG(pVM, &pVM->csam.s.StatNrBytesRead, STAMTYPE_COUNTER, "/CSAM/BytesRead", STAMUNIT_OCCURENCES, "The number of bytes read for scanning.");
161	STAM_REG(pVM, &pVM->csam.s.StatNrOpcodeRead, STAMTYPE_COUNTER, "/CSAM/OpcodeBytesRead", STAMUNIT_OCCURENCES, "The number of opcode bytes read by the recompiler.");
162
163	STAM_REG(pVM, &pVM->csam.s.StatBitmapAlloc, STAMTYPE_COUNTER, "/CSAM/Alloc/PageBitmap", STAMUNIT_OCCURENCES, "The number of page bitmap allocations.");
164
165	STAM_REG(pVM, &pVM->csam.s.StatInstrCacheHit, STAMTYPE_COUNTER, "/CSAM/Cache/Hit", STAMUNIT_OCCURENCES, "The number of dangerous instruction cache hits.");
166	STAM_REG(pVM, &pVM->csam.s.StatInstrCacheMiss, STAMTYPE_COUNTER, "/CSAM/Cache/Miss", STAMUNIT_OCCURENCES, "The number of dangerous instruction cache misses.");
167
168	STAM_REG(pVM, &pVM->csam.s.StatScanNextFunction, STAMTYPE_COUNTER, "/CSAM/Function/Scan/Success", STAMUNIT_OCCURENCES, "The number of found functions beyond the ret border.");
169	STAM_REG(pVM, &pVM->csam.s.StatScanNextFunctionFailed, STAMTYPE_COUNTER, "/CSAM/Function/Scan/Failed", STAMUNIT_OCCURENCES, "The number of refused functions beyond the ret border.");
170
171	STAM_REG(pVM, &pVM->csam.s.StatTime, STAMTYPE_PROFILE, "/PROF/CSAM/Scan", STAMUNIT_TICKS_PER_CALL, "Scanning overhead.");
172	STAM_REG(pVM, &pVM->csam.s.StatTimeCheckAddr, STAMTYPE_PROFILE, "/PROF/CSAM/CheckAddr", STAMUNIT_TICKS_PER_CALL, "Address check overhead.");
173	STAM_REG(pVM, &pVM->csam.s.StatTimeAddrConv, STAMTYPE_PROFILE, "/PROF/CSAM/AddrConv", STAMUNIT_TICKS_PER_CALL, "Address conversion overhead.");
174	STAM_REG(pVM, &pVM->csam.s.StatTimeFlushPage, STAMTYPE_PROFILE, "/PROF/CSAM/FlushPage", STAMUNIT_TICKS_PER_CALL, "Page flushing overhead.");
175	STAM_REG(pVM, &pVM->csam.s.StatTimeDisasm, STAMTYPE_PROFILE, "/PROF/CSAM/Disasm", STAMUNIT_TICKS_PER_CALL, "Disassembly overhead.");
176	STAM_REG(pVM, &pVM->csam.s.StatFlushDirtyPages, STAMTYPE_PROFILE, "/PROF/CSAM/FlushDirtyPage", STAMUNIT_TICKS_PER_CALL, "Dirty page flushing overhead.");
177	STAM_REG(pVM, &pVM->csam.s.StatCheckGates, STAMTYPE_PROFILE, "/PROF/CSAM/CheckGates", STAMUNIT_TICKS_PER_CALL, "CSAMR3CheckGates overhead.");
178
179	/*
180	* Check CFGM option and enable/disable CSAM.
181	*/
182	bool fEnabled;
183	rc = CFGMR3QueryBool(CFGMR3GetRoot(pVM), "CSAMEnabled", &fEnabled);
184	if (VBOX_FAILURE(rc))
185	#ifdef CSAM_ENABLE
186	fEnabled = true;
187	#else
188	fEnabled = false;
189	#endif
190	if (fEnabled)
191	CSAMEnableScanning(pVM);
192
193	#ifdef VBOX_WITH_DEBUGGER
194	/*
195	* Debugger commands.
196	*/
197	static bool fRegisteredCmds = false;
198	if (!fRegisteredCmds)
199	{
200	int rc = DBGCRegisterCommands(&g_aCmds[0], ELEMENTS(g_aCmds));
201	if (VBOX_SUCCESS(rc))
202	fRegisteredCmds = true;
203	}
204	#endif
205
206	return VINF_SUCCESS;
207	}
208
209	/**
210	* (Re)initializes CSAM
211	*
212	* @param pVM The VM.
213	*/
214	static int csamReinit(PVM pVM)
215	{
216	/*
217	* Assert alignment and sizes.
218	*/
219	AssertRelease(!(RT_OFFSETOF(VM, csam.s) & 31));
220	AssertRelease(sizeof(pVM->csam.s) <= sizeof(pVM->csam.padding));
221
222	/*
223	* Setup any fixed pointers and offsets.
224	*/
225	pVM->csam.s.offVM = RT_OFFSETOF(VM, patm);
226
227	pVM->csam.s.fGatesChecked = false;
228	pVM->csam.s.fScanningStarted = false;
229
230	VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
231	pVM->csam.s.cDirtyPages = 0;
232	/* not necessary */
233	memset(pVM->csam.s.pvDirtyBasePage, 0, sizeof(pVM->csam.s.pvDirtyBasePage));
234	memset(pVM->csam.s.pvDirtyFaultPage, 0, sizeof(pVM->csam.s.pvDirtyFaultPage));
235
236	memset(&pVM->csam.s.aDangerousInstr, 0, sizeof(pVM->csam.s.aDangerousInstr));
237	pVM->csam.s.cDangerousInstr = 0;
238	pVM->csam.s.iDangerousInstr = 0;
239
240	/** @note never mess with the pgdir bitmap here! */
241	return VINF_SUCCESS;
242	}
243
244	/**
245	* Applies relocations to data and code managed by this
246	* component. This function will be called at init and
247	* whenever the VMM need to relocate itself inside the GC.
248	*
249	* The csam will update the addresses used by the switcher.
250	*
251	* @param pVM The VM.
252	* @param offDelta Relocation delta.
253	*/
254	CSAMR3DECL(void) CSAMR3Relocate(PVM pVM, RTGCINTPTR offDelta)
255	{
256	if (offDelta)
257	{
258	/* Adjust pgdir and page bitmap pointers. */
259	pVM->csam.s.pPDBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDGCBitmapHC);
260	pVM->csam.s.pPDHCBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC);
261
262	for(int i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
263	{
264	if (pVM->csam.s.pPDGCBitmapHC[i])
265	{
266	pVM->csam.s.pPDGCBitmapHC[i] += offDelta;
267	}
268	}
269	}
270	return;
271	}
272
273	/**
274	* Terminates the csam.
275	*
276	* Termination means cleaning up and freeing all resources,
277	* the VM it self is at this point powered off or suspended.
278	*
279	* @returns VBox status code.
280	* @param pVM The VM to operate on.
281	*/
282	CSAMR3DECL(int) CSAMR3Term(PVM pVM)
283	{
284	int rc;
285
286	rc = CSAMR3Reset(pVM);
287	AssertRC(rc);
288
289	/* @todo triggers assertion in MMHyperFree */
290	#if 0
291	for(int i=0;i<CSAM_PAGEBMP_CHUNKS;i++)
292	{
293	if (pVM->csam.s.pPDBitmapHC[i])
294	MMHyperFree(pVM, pVM->csam.s.pPDBitmapHC[i]);
295	}
296	#endif
297
298	return VINF_SUCCESS;
299	}
300
301	/**
302	* CSAM reset callback.
303	*
304	* @returns VBox status code.
305	* @param pVM The VM which is reset.
306	*/
307	CSAMR3DECL(int) CSAMR3Reset(PVM pVM)
308	{
309	/* Clear page bitmaps. */
310	for(int i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
311	{
312	if (pVM->csam.s.pPDBitmapHC[i])
313	{
314	Assert((CSAM_PAGE_BITMAP_SIZE& 3) == 0);
315	ASMMemZero32(pVM->csam.s.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
316	}
317	}
318
319	/* Remove all CSAM page records. */
320	while(true)
321	{
322	PCSAMPAGEREC pPageRec = (PCSAMPAGEREC)RTAvlPVGetBestFit(&pVM->csam.s.pPageTree, 0, true);
323	if (pPageRec)
324	{
325	csamRemovePageRecord(pVM, pPageRec->page.pPageGC);
326	}
327	else
328	break;
329	}
330	Assert(!pVM->csam.s.pPageTree);
331
332	csamReinit(pVM);
333
334	return VINF_SUCCESS;
335	}
336
337	#define CSAM_SUBTRACT_PTR(a, b) (uintptr_t )&(a) = (uintptr_t)(a) - (uintptr_t)(b)
338	#define CSAM_ADD_PTR(a, b) (uintptr_t )&(a) = (uintptr_t)(a) + (uintptr_t)(b)
339
340
341	/**
342	* Callback function for RTAvlPVDoWithAll
343	*
344	* Counts the number of records in the tree
345	*
346	* @returns VBox status code.
347	* @param pNode Current node
348	* @param pcPatches Pointer to patch counter
349	*/
350	static DECLCALLBACK(int) CountRecord(PAVLPVNODECORE pNode, void *pcPatches)
351	{
352	(uint32_t )pcPatches = (uint32_t )pcPatches + 1;
353	return VINF_SUCCESS;
354	}
355
356	/**
357	* Callback function for RTAvlPVDoWithAll
358	*
359	* Saves the state of the page record
360	*
361	* @returns VBox status code.
362	* @param pNode Current node
363	* @param pVM1 VM Handle
364	*/
365	static DECLCALLBACK(int) SavePageState(PAVLPVNODECORE pNode, void *pVM1)
366	{
367	PVM pVM = (PVM)pVM1;
368	PCSAMPAGEREC pPage = (PCSAMPAGEREC)pNode;
369	CSAMPAGEREC page = *pPage;
370	PSSMHANDLE pSSM = pVM->csam.s.savedstate.pSSM;
371	int rc;
372
373	/* Save the page record itself */
374	rc = SSMR3PutMem(pSSM, &page, sizeof(page));
375	AssertRCReturn(rc, rc);
376
377	if (page.page.pBitmap)
378	{
379	rc = SSMR3PutMem(pSSM, page.page.pBitmap, CSAM_PAGE_BITMAP_SIZE);
380	AssertRCReturn(rc, rc);
381	}
382
383	return VINF_SUCCESS;
384	}
385
386	/**
387	* Execute state save operation.
388	*
389	* @returns VBox status code.
390	* @param pVM VM Handle.
391	* @param pSSM SSM operation handle.
392	*/
393	static DECLCALLBACK(int) csamr3Save(PVM pVM, PSSMHANDLE pSSM)
394	{
395	CSAM csamInfo = pVM->csam.s;
396	int rc;
397
398	/*
399	* Count the number of page records in the tree (feeling lazy)
400	*/
401	csamInfo.savedstate.cPageRecords = 0;
402	RTAvlPVDoWithAll(&pVM->csam.s.pPageTree, true, CountRecord, &csamInfo.savedstate.cPageRecords);
403
404	/*
405	* Save CSAM structure
406	*/
407	pVM->csam.s.savedstate.pSSM = pSSM;
408	rc = SSMR3PutMem(pSSM, &csamInfo, sizeof(csamInfo));
409	AssertRCReturn(rc, rc);
410
411	/* Save pgdir bitmap */
412	rc = SSMR3PutMem(pSSM, csamInfo.pPDBitmapHC, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR));
413	AssertRCReturn(rc, rc);
414
415	for (unsigned i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
416	{
417	if(csamInfo.pPDBitmapHC[i])
418	{
419	/* Save the page bitmap. */
420	rc = SSMR3PutMem(pSSM, csamInfo.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
421	AssertRCReturn(rc, rc);
422	}
423	}
424
425	/*
426	* Save page records
427	*/
428	rc = RTAvlPVDoWithAll(&pVM->csam.s.pPageTree, true, SavePageState, pVM);
429	AssertRCReturn(rc, rc);
430
431	/** @note we don't restore aDangerousInstr; it will be recreated automatically. */
432	return VINF_SUCCESS;
433	}
434
435	/**
436	* Execute state load operation.
437	*
438	* @returns VBox status code.
439	* @param pVM VM Handle.
440	* @param pSSM SSM operation handle.
441	* @param u32Version Data layout version.
442	*/
443	static DECLCALLBACK(int) csamr3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version)
444	{
445	int rc;
446	CSAM csamInfo;
447
448	if (u32Version != CSAM_SSM_VERSION)
449	return VERR_SSM_UNSUPPORTED_DATA_UNIT_VERSION;
450
451	pVM->csam.s.savedstate.pSSM = pSSM;
452
453	/*
454	* Restore CSAM structure
455	*/
456	rc = SSMR3GetMem(pSSM, &csamInfo, sizeof(csamInfo));
457	AssertRCReturn(rc, rc);
458
459	pVM->csam.s.fGatesChecked = csamInfo.fGatesChecked;
460	pVM->csam.s.fScanningStarted = csamInfo.fScanningStarted;
461
462	/* Restore dirty code page info. */
463	pVM->csam.s.cDirtyPages = csamInfo.cDirtyPages;
464	memcpy(pVM->csam.s.pvDirtyBasePage, csamInfo.pvDirtyBasePage, sizeof(pVM->csam.s.pvDirtyBasePage));
465	memcpy(pVM->csam.s.pvDirtyFaultPage, csamInfo.pvDirtyFaultPage, sizeof(pVM->csam.s.pvDirtyFaultPage));
466
467	/* Restore possible code page */
468	pVM->csam.s.cPossibleCodePages = csamInfo.cPossibleCodePages;
469	memcpy(pVM->csam.s.pvPossibleCodePage, csamInfo.pvPossibleCodePage, sizeof(pVM->csam.s.pvPossibleCodePage));
470
471	/* Restore pgdir bitmap (we'll change the pointers next). */
472	rc = SSMR3GetMem(pSSM, pVM->csam.s.pPDBitmapHC, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR));
473	AssertRCReturn(rc, rc);
474
475	/*
476	* Restore page bitmaps
477	*/
478	for (unsigned i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
479	{
480	if(pVM->csam.s.pPDBitmapHC[i])
481	{
482	rc = MMHyperAlloc(pVM, CSAM_PAGE_BITMAP_SIZE, 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDBitmapHC[i]);
483	if (VBOX_FAILURE(rc))
484	{
485	Log(("MMR3HyperAlloc failed with %d\n", rc));
486	return rc;
487	}
488	/* Convert to GC pointer. */
489	pVM->csam.s.pPDGCBitmapHC[i] = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC[i]);
490	Assert(pVM->csam.s.pPDGCBitmapHC[i]);
491
492	/* Restore the bitmap. */
493	rc = SSMR3GetMem(pSSM, pVM->csam.s.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
494	AssertRCReturn(rc, rc);
495	}
496	else
497	{
498	Assert(!pVM->csam.s.pPDGCBitmapHC[i]);
499	pVM->csam.s.pPDGCBitmapHC[i] = 0;
500	}
501	}
502
503	/*
504	* Restore page records
505	*/
506	for (uint32_t i=0;i<csamInfo.savedstate.cPageRecords + csamInfo.savedstate.cPatchPageRecords;i++)
507	{
508	CSAMPAGEREC page;
509	PCSAMPAGE pPage;
510
511	rc = SSMR3GetMem(pSSM, &page, sizeof(page));
512	AssertRCReturn(rc, rc);
513
514	/*
515	* Recreate the page record
516	*/
517	pPage = csamCreatePageRecord(pVM, page.page.pPageGC, page.page.enmTag, page.page.fCode32, page.page.fMonitorInvalidation);
518	AssertReturn(pPage, VERR_NO_MEMORY);
519
520	pPage->GCPhys = page.page.GCPhys;
521	pPage->fFlags = page.page.fFlags;
522	pPage->u64Hash = page.page.u64Hash;
523
524	if (page.page.pBitmap)
525	{
526	rc = SSMR3GetMem(pSSM, pPage->pBitmap, CSAM_PAGE_BITMAP_SIZE);
527	AssertRCReturn(rc, rc);
528	}
529	else
530	{
531	MMR3HeapFree(pPage->pBitmap);
532	pPage->pBitmap = 0;
533	}
534	}
535
536	/** @note we don't restore aDangerousInstr; it will be recreated automatically. */
537	memset(&pVM->csam.s.aDangerousInstr, 0, sizeof(pVM->csam.s.aDangerousInstr));
538	pVM->csam.s.cDangerousInstr = 0;
539	pVM->csam.s.iDangerousInstr = 0;
540	return VINF_SUCCESS;
541	}
542
543	/**
544	* Convert guest context address to host context pointer
545	*
546	* @returns VBox status code.
547	* @param pVM The VM to operate on.
548	* @param pCacheRec Address conversion cache record
549	* @param pGCPtr Guest context pointer
550	*
551	* @returns Host context pointer or NULL in case of an error
552	*
553	*/
554	static HCPTRTYPE(void ) CSAMGCVirtToHCVirt(PVM pVM, PCSAMP2GLOOKUPREC pCacheRec, GCPTRTYPE(uint8_t )pGCPtr)
555	{
556	int rc;
557	HCPTRTYPE(void *)pHCPtr;
558
559	STAM_PROFILE_START(&pVM->csam.s.StatTimeAddrConv, a);
560
561	pHCPtr = PATMR3GCPtrToHCPtr(pVM, pGCPtr);
562	if (pHCPtr) return pHCPtr;
563
564	if (pCacheRec->pPageLocStartHC)
565	{
566	uint32_t offset = pGCPtr & PAGE_OFFSET_MASK;
567	if (pCacheRec->pGuestLoc == (pGCPtr & PAGE_BASE_GC_MASK))
568	{
569	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
570	return pCacheRec->pPageLocStartHC + offset;
571	}
572	}
573
574	rc = PGMPhysGCPtr2HCPtr(pVM, pGCPtr, &pHCPtr);
575	if (rc != VINF_SUCCESS)
576	{
577	//// AssertMsgRC(rc, ("MMR3PhysGCVirt2HCVirtEx failed for %VGv\n", pGCPtr));
578	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
579	return NULL;
580	}
581	////invalid? Assert(sizeof(HCPTRTYPE(uint8_t*)) == sizeof(uint32_t));
582
583	pCacheRec->pPageLocStartHC = (HCPTRTYPE(uint8_t*))((RTHCUINTPTR)pHCPtr & PAGE_BASE_HC_MASK);
584	pCacheRec->pGuestLoc = pGCPtr & PAGE_BASE_GC_MASK;
585	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
586	return pHCPtr;
587	}
588
589	/**
590	* Read callback for disassembly function; supports reading bytes that cross a page boundary
591	*
592	* @returns VBox status code.
593	* @param pSrc GC source pointer
594	* @param pDest HC destination pointer
595	* @param size Number of bytes to read
596	* @param dwUserdata Callback specific user data (pCpu)
597	*
598	*/
599	int32_t CSAMR3ReadBytes(RTHCUINTPTR pSrc, uint8_t *pDest, uint32_t size, RTHCUINTPTR dwUserdata)
600	{
601	DISCPUSTATE pCpu = (DISCPUSTATE )dwUserdata;
602	PVM pVM = (PVM)pCpu->dwUserData[0];
603	RTHCUINTPTR pInstrHC = pCpu->dwUserData[1];
604	RTGCUINTPTR pInstrGC = pCpu->dwUserData[2];
605	int orgsize = size;
606
607	Assert(sizeof(RTHCUINTPTR) <= sizeof(pCpu->dwUserData[0]));
608	Assert(sizeof(RTGCUINTPTR) <= sizeof(pCpu->dwUserData[0]));
609
610	/* We are not interested in patched instructions, so read the original opcode bytes. */
611	/** @note single instruction patches (int3) are checked in CSAMR3AnalyseCallback */
612	for (int i=0;i<orgsize;i++)
613	{
614	int rc = PATMR3QueryOpcode(pVM, (RTGCPTR)pSrc, pDest);
615	if (VBOX_SUCCESS(rc))
616	{
617	pSrc++;
618	pDest++;
619	size--;
620	}
621	else
622	break;
623	}
624	if (size == 0)
625	return VINF_SUCCESS;
626
627	if (PAGE_ADDRESS(pInstrGC) != PAGE_ADDRESS(pSrc + size - 1) && !PATMIsPatchGCAddr(pVM, pSrc))
628	{
629	return PGMPhysReadGCPtr(pVM, pDest, pSrc, size);
630	}
631	else
632	{
633	Assert(pInstrHC);
634
635	/* pInstrHC is the base address; adjust according to the GC pointer. */
636	pInstrHC = pInstrHC + (pSrc - pInstrGC);
637
638	memcpy(pDest, (void *)pInstrHC, size);
639	}
640
641	return VINF_SUCCESS;
642	}
643
644	inline bool CSAMR3DISInstr(PVM pVM, DISCPUSTATE pCpu, RTGCPTR InstrGC, uint8_t InstrHC, uint32_t pOpsize, char pszOutput)
645	{
646	(pCpu)->pfnReadBytes = CSAMR3ReadBytes;
647	(pCpu)->dwUserData[0] = (RTHCUINTPTR)pVM;
648	(pCpu)->dwUserData[1] = (RTHCUINTPTR)InstrHC;
649	(pCpu)->dwUserData[2] = (RTHCUINTPTR)InstrGC;
650	#ifdef DEBUG
651	return DISInstrEx(pCpu, InstrGC, 0, pOpsize, pszOutput, OPTYPE_ALL);
652	#else
653	/* We are interested in everything except harmless stuff */
654	return DISInstrEx(pCpu, InstrGC, 0, pOpsize, pszOutput, ~(OPTYPE_INVALID \| OPTYPE_HARMLESS \| OPTYPE_RRM_MASK));
655	#endif
656	}
657
658	/**
659	* Analyses the instructions following the cli for compliance with our heuristics for cli
660	*
661	* @returns VBox status code.
662	* @param pVM The VM to operate on.
663	* @param pCpu CPU disassembly state
664	* @param pInstrGC Guest context pointer to privileged instruction
665	* @param pCurInstrGC Guest context pointer to the current instruction
666	* @param pCacheRec GC to HC cache record
667	* @param pUserData User pointer (callback specific)
668	*
669	*/
670	static int CSAMR3AnalyseCallback(PVM pVM, DISCPUSTATE pCpu, GCPTRTYPE(uint8_t ) pInstrGC, GCPTRTYPE(uint8_t *) pCurInstrGC,
671	PCSAMP2GLOOKUPREC pCacheRec, void *pUserData)
672	{
673	PCSAMPAGE pPage = (PCSAMPAGE)pUserData;
674	int rc;
675
676	switch(pCpu->pCurInstr->opcode)
677	{
678	case OP_INT:
679	Assert(pCpu->param1.flags & USE_IMMEDIATE8);
680	if (pCpu->param1.parval == 3)
681	{
682	//two byte int 3
683	return VINF_SUCCESS;
684	}
685	break;
686
687	case OP_ILLUD2:
688	/* This appears to be some kind of kernel panic in Linux 2.4; no point to continue. */
689	case OP_RETN:
690	case OP_INT3:
691	case OP_INVALID:
692	#if 1
693	/* removing breaks win2k guests? */
694	case OP_IRET:
695	#endif
696	return VINF_SUCCESS;
697	}
698
699	// Check for exit points
700	switch (pCpu->pCurInstr->opcode)
701	{
702	/* It's not a good idea to patch pushf instructions:
703	* - increases the chance of conflicts (code jumping to the next instruction)
704	* - better to patch the cli
705	* - code that branches before the cli will likely hit an int 3
706	* - in general doesn't offer any benefits as we don't allow nested patch blocks (IF is always 1)
707	*/
708	case OP_PUSHF:
709	case OP_POPF:
710	break;
711
712	case OP_CLI:
713	{
714	uint32_t cbInstr = 0;
715	uint32_t opsize = pCpu->opsize;
716
717	PATMR3AddHint(pVM, pCurInstrGC, (pPage->fCode32) ? PATMFL_CODE32 : 0);
718
719	/* Make sure the instructions that follow the cli have not been encountered before. */
720	while (true)
721	{
722	DISCPUSTATE cpu;
723	uint8_t *pCurInstrHC = 0;
724	bool disret;
725
726	if (cbInstr + opsize >= SIZEOF_NEARJUMP32)
727	break;
728
729	if (csamIsCodeScanned(pVM, pCurInstrGC + opsize, &pPage) == true)
730	{
731	/* We've scanned the next instruction(s) already. This means we've followed a branch that ended up there before -> dangerous!! */
732	PATMR3DetectConflict(pVM, pCurInstrGC, pCurInstrGC + opsize);
733	break;
734	}
735	pCurInstrGC += opsize;
736	cbInstr += opsize;
737
738	pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
739	if (pCurInstrHC == NULL)
740	{
741	Log(("CSAMGCVirtToHCVirt failed for %VGv\n", pCurInstrGC));
742	break;
743	}
744	Assert(VALID_PTR(pCurInstrHC));
745
746	cpu.mode = (pPage->fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
747	disret = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
748	Assert(disret == true);
749	if (disret == false)
750	break;
751	}
752	break;
753	}
754
755	case OP_PUSH:
756	if (pCpu->pCurInstr->param1 != OP_PARM_REG_CS)
757	break;
758
759	/* no break */
760	case OP_STR:
761	case OP_LSL:
762	case OP_LAR:
763	case OP_SGDT:
764	case OP_SLDT:
765	case OP_SIDT:
766	case OP_SMSW:
767	case OP_VERW:
768	case OP_VERR:
769	case OP_CPUID:
770	case OP_IRET:
771	#ifdef DEBUG
772	switch(pCpu->pCurInstr->opcode)
773	{
774	case OP_STR:
775	Log(("Privileged instruction at %VGv: str!!\n", pCurInstrGC));
776	break;
777	case OP_LSL:
778	Log(("Privileged instruction at %VGv: lsl!!\n", pCurInstrGC));
779	break;
780	case OP_LAR:
781	Log(("Privileged instruction at %VGv: lar!!\n", pCurInstrGC));
782	break;
783	case OP_SGDT:
784	Log(("Privileged instruction at %VGv: sgdt!!\n", pCurInstrGC));
785	break;
786	case OP_SLDT:
787	Log(("Privileged instruction at %VGv: sldt!!\n", pCurInstrGC));
788	break;
789	case OP_SIDT:
790	Log(("Privileged instruction at %VGv: sidt!!\n", pCurInstrGC));
791	break;
792	case OP_SMSW:
793	Log(("Privileged instruction at %VGv: smsw!!\n", pCurInstrGC));
794	break;
795	case OP_VERW:
796	Log(("Privileged instruction at %VGv: verw!!\n", pCurInstrGC));
797	break;
798	case OP_VERR:
799	Log(("Privileged instruction at %VGv: verr!!\n", pCurInstrGC));
800	break;
801	case OP_CPUID:
802	Log(("Privileged instruction at %VGv: cpuid!!\n", pCurInstrGC));
803	break;
804	case OP_PUSH:
805	Log(("Privileged instruction at %VGv: push cs!!\n", pCurInstrGC));
806	break;
807	case OP_IRET:
808	Log(("Privileged instruction at %VGv: iret!!\n", pCurInstrGC));
809	break;
810	}
811	#endif
812
813	if (PATMR3HasBeenPatched(pVM, pCurInstrGC) == false)
814	{
815	rc = PATMR3InstallPatch(pVM, pCurInstrGC, (pPage->fCode32) ? PATMFL_CODE32 : 0);
816	if (VBOX_FAILURE(rc))
817	{
818	Log(("PATMR3InstallPatch failed with %d\n", rc));
819	return VWRN_CONTINUE_ANALYSIS;
820	}
821	}
822	if (pCpu->pCurInstr->opcode == OP_IRET)
823	return VINF_SUCCESS; /* Look no further in this branch. */
824
825	return VWRN_CONTINUE_ANALYSIS;
826
827	case OP_JMP:
828	case OP_CALL:
829	{
830	// return or jump/call through a jump table
831	if (OP_PARM_VTYPE(pCpu->pCurInstr->param1) != OP_PARM_J)
832	{
833	#ifdef DEBUG
834	switch(pCpu->pCurInstr->opcode)
835	{
836	case OP_JMP:
837	Log(("Control Flow instruction at %VGv: jmp!!\n", pCurInstrGC));
838	break;
839	case OP_CALL:
840	Log(("Control Flow instruction at %VGv: call!!\n", pCurInstrGC));
841	break;
842	}
843	#endif
844	return VWRN_CONTINUE_ANALYSIS;
845	}
846	return VWRN_CONTINUE_ANALYSIS;
847	}
848
849	}
850
851	return VWRN_CONTINUE_ANALYSIS;
852	}
853
854	#ifdef CSAM_ANALYSE_BEYOND_RET
855	/**
856	* Wrapper for csamAnalyseCodeStream for call instructions.
857	*
858	* @returns VBox status code.
859	* @param pVM The VM to operate on.
860	* @param pInstrGC Guest context pointer to privileged instruction
861	* @param pCurInstrGC Guest context pointer to the current instruction
862	* @param fCode32 16 or 32 bits code
863	* @param pfnCSAMR3Analyse Callback for testing the disassembled instruction
864	* @param pUserData User pointer (callback specific)
865	*
866	*/
867	static int csamAnalyseCallCodeStream(PVM pVM, GCPTRTYPE(uint8_t ) pInstrGC, GCPTRTYPE(uint8_t ) pCurInstrGC, bool fCode32,
868	PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec)
869	{
870	int rc;
871	CSAMCALLEXITREC CallExitRec;
872	PCSAMCALLEXITREC pOldCallRec;
873	PCSAMPAGE pPage = 0;
874	uint32_t i;
875
876	CallExitRec.cInstrAfterRet = 0;
877
878	pOldCallRec = pCacheRec->pCallExitRec;
879	pCacheRec->pCallExitRec = &CallExitRec;
880
881	rc = csamAnalyseCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
882
883	for (i=0;i<CallExitRec.cInstrAfterRet;i++)
884	{
885	PCSAMPAGE pPage = 0;
886
887	pCurInstrGC = CallExitRec.pInstrAfterRetGC[i];
888
889	/* Check if we've previously encountered the instruction after the ret. */
890	if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
891	{
892	DISCPUSTATE cpu;
893	uint32_t opsize;
894	uint8_t *pCurInstrHC = 0;
895	bool disret;
896	#ifdef DEBUG
897	char szOutput[256];
898	#endif
899	if (pPage == NULL)
900	{
901	/* New address; let's take a look at it. */
902	pPage = csamCreatePageRecord(pVM, pCurInstrGC, CSAM_TAG_CSAM, fCode32);
903	if (pPage == NULL)
904	{
905	rc = VERR_NO_MEMORY;
906	goto done;
907	}
908	}
909
910	/**
911	* Some generic requirements for recognizing an adjacent function:
912	* - alignment fillers that consist of:
913	* - nop
914	* - lea genregX, [genregX (+ 0)]
915	* - push ebp after the filler (can extend this later); aligned at at least a 4 byte boundary
916	*/
917	for (int j=0;j<16;j++)
918	{
919	pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
920	if (pCurInstrHC == NULL)
921	{
922	Log(("CSAMGCVirtToHCVirt failed for %VGv\n", pCurInstrGC));
923	goto done;
924	}
925	Assert(VALID_PTR(pCurInstrHC));
926
927	cpu.mode = (fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
928	STAM_PROFILE_START(&pVM->csam.s.StatTimeDisasm, a);
929	#ifdef DEBUG
930	disret = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, szOutput);
931	if (disret == true) Log(("CSAM Call Analysis: %s", szOutput));
932	#else
933	disret = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
934	#endif
935	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeDisasm, a);
936	if (disret == false)
937	{
938	Log(("Disassembly failed at %VGv (probably page not present) -> return to caller\n", pCurInstrGC));
939	goto done;
940	}
941
942	STAM_COUNTER_ADD(&pVM->csam.s.StatNrBytesRead, opsize);
943
944	GCPTRTYPE(uint8_t *) addr = 0;
945	PCSAMPAGE pJmpPage = NULL;
946
947	if (PAGE_ADDRESS(pCurInstrGC) != PAGE_ADDRESS(pCurInstrGC + opsize - 1))
948	{
949	if (!PGMGstIsPagePresent(pVM, pCurInstrGC + opsize - 1))
950	{
951	/// @todo fault in the page
952	Log(("Page for current instruction %VGv is not present!!\n", pCurInstrGC));
953	goto done;
954	}
955	//all is fine, let's continue
956	csamR3CheckPageRecord(pVM, pCurInstrGC + opsize - 1);
957	}
958
959	switch (cpu.pCurInstr->opcode)
960	{
961	case OP_NOP:
962	case OP_INT3:
963	break; /* acceptable */
964
965	case OP_LEA:
966	/* Must be similar to:
967	*
968	* lea esi, [esi]
969	* lea esi, [esi+0]
970	* Any register is allowed as long as source and destination are identical.
971	*/
972	if ( cpu.param1.flags != USE_REG_GEN32
973	\|\| ( cpu.param2.flags != USE_REG_GEN32
974	&& ( !(cpu.param2.flags & USE_REG_GEN32)
975	\|\| !(cpu.param2.flags & (USE_DISPLACEMENT8\|USE_DISPLACEMENT16\|USE_DISPLACEMENT32))
976	\|\| cpu.param2.parval != 0
977	)
978	)
979	\|\| cpu.param1.base.reg_gen32 != cpu.param2.base.reg_gen32
980	)
981	{
982	STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
983	goto next_function;
984	}
985	break;
986
987	case OP_PUSH:
988	{
989	if ( (pCurInstrGC & 0x3) != 0
990	\|\| cpu.param1.flags != USE_REG_GEN32
991	\|\| cpu.param1.base.reg_gen32 != USE_REG_EBP
992	)
993	{
994	STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
995	goto next_function;
996	}
997
998	if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
999	{
1000	CSAMCALLEXITREC CallExitRec2;
1001	CallExitRec2.cInstrAfterRet = 0;
1002
1003	pCacheRec->pCallExitRec = &CallExitRec2;
1004
1005	/* Analyse the function. */
1006	Log(("Found new function at %VGv\n", pCurInstrGC));
1007	STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunction);
1008	csamAnalyseCallCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
1009	}
1010	goto next_function;
1011	}
1012
1013	case OP_SUB:
1014	{
1015	if ( (pCurInstrGC & 0x3) != 0
1016	\|\| cpu.param1.flags != USE_REG_GEN32
1017	\|\| cpu.param1.base.reg_gen32 != USE_REG_ESP
1018	)
1019	{
1020	STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
1021	goto next_function;
1022	}
1023
1024	if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
1025	{
1026	CSAMCALLEXITREC CallExitRec2;
1027	CallExitRec2.cInstrAfterRet = 0;
1028
1029	pCacheRec->pCallExitRec = &CallExitRec2;
1030
1031	/* Analyse the function. */
1032	Log(("Found new function at %VGv\n", pCurInstrGC));
1033	STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunction);
1034	csamAnalyseCallCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
1035	}
1036	goto next_function;
1037	}
1038
1039	default:
1040	STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
1041	goto next_function;
1042	}
1043	/* Mark it as scanned. */
1044	csamMarkCode(pVM, pPage, pCurInstrGC, opsize, true);
1045	pCurInstrGC += opsize;
1046	} /* for at most 16 instructions */
1047	next_function:
1048	; /* MSVC complains otherwise */
1049	}
1050	}
1051	done:
1052	pCacheRec->pCallExitRec = pOldCallRec;
1053	return rc;
1054	}
1055	#else
1056	#define csamAnalyseCallCodeStream csamAnalyseCodeStream
1057	#endif
1058
1059	/**
1060	* Disassembles the code stream until the callback function detects a failure or decides everything is acceptable
1061	*
1062	* @returns VBox status code.
1063	* @param pVM The VM to operate on.
1064	* @param pInstrGC Guest context pointer to privileged instruction
1065	* @param pCurInstrGC Guest context pointer to the current instruction
1066	* @param fCode32 16 or 32 bits code
1067	* @param pfnCSAMR3Analyse Callback for testing the disassembled instruction
1068	* @param pUserData User pointer (callback specific)
1069	*
1070	*/
1071	static int csamAnalyseCodeStream(PVM pVM, GCPTRTYPE(uint8_t ) pInstrGC, GCPTRTYPE(uint8_t ) pCurInstrGC, bool fCode32,
1072	PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec)
1073	{
1074	DISCPUSTATE cpu;
1075	PCSAMPAGE pPage = (PCSAMPAGE)pUserData;
1076	int rc = VWRN_CONTINUE_ANALYSIS;
1077	uint32_t opsize;
1078	HCPTRTYPE(uint8_t *)pCurInstrHC = 0;
1079	bool disret;
1080
1081	#ifdef DEBUG
1082	char szOutput[256];
1083	#endif
1084
1085	LogFlow(("csamAnalyseCodeStream: code at %VGv depth=%d\n", pCurInstrGC, pCacheRec->depth));
1086
1087	pVM->csam.s.fScanningStarted = true;
1088
1089	pCacheRec->depth++;
1090	/*
1091	* Limit the call depth. (rather arbitrary upper limit; too low and we won't detect certain
1092	* cpuid instructions in Linux kernels; too high and we waste too much time scanning code)
1093	* (512 is necessary to detect cpuid instructions in Red Hat EL4; see defect 1355)
1094	* @note we are using a lot of stack here. couple of 100k when we go to the full depth (!)
1095	*/
1096	if (pCacheRec->depth > 512)
1097	{
1098	LogFlow(("CSAM: maximum calldepth reached for %VGv\n", pCurInstrGC));
1099	pCacheRec->depth--;
1100	return VINF_SUCCESS; //let's not go on forever
1101	}
1102
1103	Assert(!PATMIsPatchGCAddr(pVM, pCurInstrGC));
1104	csamR3CheckPageRecord(pVM, pCurInstrGC);
1105
1106	while(rc == VWRN_CONTINUE_ANALYSIS)
1107	{
1108	if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
1109	{
1110	if (pPage == NULL)
1111	{
1112	/* New address; let's take a look at it. */
1113	pPage = csamCreatePageRecord(pVM, pCurInstrGC, CSAM_TAG_CSAM, fCode32);
1114	if (pPage == NULL)
1115	{
1116	rc = VERR_NO_MEMORY;
1117	goto done;
1118	}
1119	}
1120	}
1121	else
1122	{
1123	LogFlow(("Code at %VGv has been scanned before\n", pCurInstrGC));
1124	rc = VINF_SUCCESS;
1125	goto done;
1126	}
1127
1128	pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
1129	if (pCurInstrHC == NULL)
1130	{
1131	Log(("CSAMGCVirtToHCVirt failed for %VGv\n", pCurInstrGC));
1132	rc = VERR_PATCHING_REFUSED;
1133	goto done;
1134	}
1135	Assert(VALID_PTR(pCurInstrHC));
1136
1137	cpu.mode = (fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
1138	STAM_PROFILE_START(&pVM->csam.s.StatTimeDisasm, a);
1139	#ifdef DEBUG
1140	disret = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, szOutput);
1141	if (disret == true) Log(("CSAM Analysis: %s", szOutput));
1142	#else
1143	disret = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
1144	#endif
1145	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeDisasm, a);
1146	if (disret == false)
1147	{
1148	Log(("Disassembly failed at %VGv (probably page not present) -> return to caller\n", pCurInstrGC));
1149	rc = VINF_SUCCESS;
1150	goto done;
1151	}
1152
1153	STAM_COUNTER_ADD(&pVM->csam.s.StatNrBytesRead, opsize);
1154
1155	csamMarkCode(pVM, pPage, pCurInstrGC, opsize, true);
1156
1157	GCPTRTYPE(uint8_t *) addr = 0;
1158	PCSAMPAGE pJmpPage = NULL;
1159
1160	if (PAGE_ADDRESS(pCurInstrGC) != PAGE_ADDRESS(pCurInstrGC + opsize - 1))
1161	{
1162	if (!PGMGstIsPagePresent(pVM, pCurInstrGC + opsize - 1))
1163	{
1164	/// @todo fault in the page
1165	Log(("Page for current instruction %VGv is not present!!\n", pCurInstrGC));
1166	rc = VWRN_CONTINUE_ANALYSIS;
1167	goto next_please;
1168	}
1169	//all is fine, let's continue
1170	csamR3CheckPageRecord(pVM, pCurInstrGC + opsize - 1);
1171	}
1172	/*
1173	* If it's harmless, then don't bother checking it (the disasm tables had better be accurate!)
1174	*/
1175	if ((cpu.pCurInstr->optype & ~OPTYPE_RRM_MASK) == OPTYPE_HARMLESS)
1176	{
1177	AssertMsg(pfnCSAMR3Analyse(pVM, &cpu, pInstrGC, pCurInstrGC, pCacheRec, (void *)pPage) == VWRN_CONTINUE_ANALYSIS, ("Instruction incorrectly marked harmless?!?!?\n"));
1178	rc = VWRN_CONTINUE_ANALYSIS;
1179	goto next_please;
1180	}
1181
1182	#ifdef CSAM_ANALYSE_BEYOND_RET
1183	/* Remember the address of the instruction following the ret in case the parent instruction was a call. */
1184	if ( pCacheRec->pCallExitRec
1185	&& cpu.pCurInstr->opcode == OP_RETN
1186	&& pCacheRec->pCallExitRec->cInstrAfterRet < CSAM_MAX_CALLEXIT_RET)
1187	{
1188	pCacheRec->pCallExitRec->pInstrAfterRetGC[pCacheRec->pCallExitRec->cInstrAfterRet] = pCurInstrGC + opsize;
1189	pCacheRec->pCallExitRec->cInstrAfterRet++;
1190	}
1191	#endif
1192
1193	rc = pfnCSAMR3Analyse(pVM, &cpu, pInstrGC, pCurInstrGC, pCacheRec, (void *)pPage);
1194	if (rc == VINF_SUCCESS)
1195	goto done;
1196
1197	// For our first attempt, we'll handle only simple relative jumps and calls (immediate offset coded in instruction)
1198	if ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1199	{
1200	addr = CSAMResolveBranch(&cpu, pCurInstrGC);
1201	if (addr == 0)
1202	{
1203	Log(("We don't support far jumps here!! (%08X)\n", cpu.param1.flags));
1204	rc = VINF_SUCCESS;
1205	break;
1206	}
1207	Assert(!PATMIsPatchGCAddr(pVM, addr));
1208
1209	/* If the target address lies in a patch generated jump, then special action needs to be taken. */
1210	PATMR3DetectConflict(pVM, pCurInstrGC, addr);
1211
1212	/* Same page? */
1213	if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pCurInstrGC ))
1214	{
1215	if (!PGMGstIsPagePresent(pVM, addr))
1216	{
1217	Log(("Page for current instruction %VGv is not present!!\n", addr));
1218	rc = VWRN_CONTINUE_ANALYSIS;
1219	goto next_please;
1220	}
1221
1222	/* All is fine, let's continue. */
1223	csamR3CheckPageRecord(pVM, addr);
1224	}
1225
1226	pJmpPage = NULL;
1227	if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1228	{
1229	if (pJmpPage == NULL)
1230	{
1231	/* New branch target; let's take a look at it. */
1232	pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1233	if (pJmpPage == NULL)
1234	{
1235	rc = VERR_NO_MEMORY;
1236	goto done;
1237	}
1238	Assert(pPage);
1239	}
1240	if (cpu.pCurInstr->opcode == OP_CALL)
1241	rc = csamAnalyseCallCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1242	else
1243	rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1244
1245	if (rc != VINF_SUCCESS) {
1246	goto done;
1247	}
1248	}
1249	if (cpu.pCurInstr->opcode == OP_JMP)
1250	{//unconditional jump; return to caller
1251	rc = VINF_SUCCESS;
1252	goto done;
1253	}
1254
1255	rc = VWRN_CONTINUE_ANALYSIS;
1256	} //if ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1257	#ifdef CSAM_SCAN_JUMP_TABLE
1258	else
1259	if ( cpu.pCurInstr->opcode == OP_JMP
1260	&& (cpu.param1.flags & (USE_DISPLACEMENT32\|USE_INDEX\|USE_SCALE)) == (USE_DISPLACEMENT32\|USE_INDEX\|USE_SCALE)
1261	)
1262	{
1263	RTGCPTR pJumpTableGC = (RTGCPTR)cpu.param1.disp32;
1264	uint8_t *pJumpTableHC;
1265	int rc2;
1266
1267	Log(("Jump through jump table\n"));
1268
1269	rc2 = PGMPhysGCPtr2HCPtr(pVM, pJumpTableGC, (PRTHCPTR)&pJumpTableHC);
1270	if (rc2 == VINF_SUCCESS)
1271	{
1272	for (uint32_t i=0;i<2;i++)
1273	{
1274	uint64_t fFlags;
1275
1276	addr = pJumpTableGC + cpu.param1.scale * i;
1277	/* Same page? */
1278	if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pJumpTableGC))
1279	break;
1280
1281	addr = (RTGCPTR )(pJumpTableHC + cpu.param1.scale * i);
1282
1283	rc2 = PGMGstGetPage(pVM, addr, &fFlags, NULL);
1284	if ( rc2 != VINF_SUCCESS
1285	\|\| (fFlags & X86_PTE_US)
1286	\|\| !(fFlags & X86_PTE_P)
1287	)
1288	break;
1289
1290	Log(("Jump to %VGv\n", addr));
1291
1292	pJmpPage = NULL;
1293	if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1294	{
1295	if (pJmpPage == NULL)
1296	{
1297	/* New branch target; let's take a look at it. */
1298	pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1299	if (pJmpPage == NULL)
1300	{
1301	rc = VERR_NO_MEMORY;
1302	goto done;
1303	}
1304	Assert(pPage);
1305	}
1306	rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1307	if (rc != VINF_SUCCESS) {
1308	goto done;
1309	}
1310	}
1311	}
1312	}
1313	}
1314	#endif
1315	if (rc != VWRN_CONTINUE_ANALYSIS) {
1316	break; //done!
1317	}
1318	next_please:
1319	if (cpu.pCurInstr->opcode == OP_JMP)
1320	{
1321	rc = VINF_SUCCESS;
1322	goto done;
1323	}
1324	pCurInstrGC += opsize;
1325	}
1326	done:
1327	pCacheRec->depth--;
1328	return rc;
1329	}
1330
1331
1332	/**
1333	* Calculates the 64 bits hash value for the current page
1334	*
1335	* @returns hash value
1336	* @param pVM The VM to operate on.
1337	* @param pInstr Page address
1338	*/
1339	uint64_t csamR3CalcPageHash(PVM pVM, RTGCPTR pInstr)
1340	{
1341	uint64_t hash = 0;
1342	uint32_t val[5];
1343	int rc;
1344
1345	Assert((pInstr & PAGE_OFFSET_MASK) == 0);
1346
1347	rc = PGMPhysReadGCPtr(pVM, &val[0], pInstr, sizeof(val[0]));
1348	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1349	if (rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT)
1350	{
1351	Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1352	return ~0ULL;
1353	}
1354
1355	rc = PGMPhysReadGCPtr(pVM, &val[1], pInstr+1024, sizeof(val[0]));
1356	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1357	if (rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT)
1358	{
1359	Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1360	return ~0ULL;
1361	}
1362
1363	rc = PGMPhysReadGCPtr(pVM, &val[2], pInstr+2048, sizeof(val[0]));
1364	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1365	if (rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT)
1366	{
1367	Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1368	return ~0ULL;
1369	}
1370
1371	rc = PGMPhysReadGCPtr(pVM, &val[3], pInstr+3072, sizeof(val[0]));
1372	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1373	if (rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT)
1374	{
1375	Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1376	return ~0ULL;
1377	}
1378
1379	rc = PGMPhysReadGCPtr(pVM, &val[4], pInstr+4092, sizeof(val[0]));
1380	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1381	if (rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT)
1382	{
1383	Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1384	return ~0ULL;
1385	}
1386
1387	// don't want to get division by zero traps
1388	val[2] \|= 1;
1389	val[4] \|= 1;
1390
1391	hash = (uint64_t)val[0] * (uint64_t)val[1] / (uint64_t)val[2] + (val[3]%val[4]);
1392	return (hash == ~0ULL) ? hash - 1 : hash;
1393	}
1394
1395
1396	/**
1397	* Notify CSAM of a page flush
1398	*
1399	* @returns VBox status code
1400	* @param pVM The VM to operate on.
1401	* @param addr GC address of the page to flush
1402	* @param fRemovePage Page removal flag
1403	*/
1404	static int csamFlushPage(PVM pVM, RTGCPTR addr, bool fRemovePage)
1405	{
1406	PCSAMPAGEREC pPageRec;
1407	int rc;
1408	RTGCPHYS GCPhys = 0;
1409	uint64_t fFlags = 0;
1410
1411	if (!CSAMIsEnabled(pVM))
1412	return VINF_SUCCESS;
1413
1414	STAM_PROFILE_START(&pVM->csam.s.StatTimeFlushPage, a);
1415
1416	addr = addr & PAGE_BASE_GC_MASK;
1417
1418	/*
1419	* Note: searching for the page in our tree first is more expensive (skipped flushes are two orders of magnitude more common)
1420	*/
1421	if (pVM->csam.s.pPageTree == NULL)
1422	{
1423	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1424	return VWRN_CSAM_PAGE_NOT_FOUND;
1425	}
1426
1427	rc = PGMGstGetPage(pVM, addr, &fFlags, &GCPhys);
1428	/* Returned at a very early stage (no paging yet presumably). */
1429	if (rc == VERR_NOT_SUPPORTED)
1430	{
1431	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1432	return rc;
1433	}
1434
1435	if (VBOX_SUCCESS(rc))
1436	{
1437	if ( (fFlags & X86_PTE_US)
1438	\|\| rc == VERR_PGM_PHYS_PAGE_RESERVED
1439	)
1440	{
1441	/* User page -> not relevant for us. */
1442	STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1443	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1444	return VINF_SUCCESS;
1445	}
1446	}
1447	else
1448	if (rc != VERR_PAGE_NOT_PRESENT && rc != VERR_PAGE_TABLE_NOT_PRESENT)
1449	AssertMsgFailed(("PGMR3GetPage %VGv failed with %Vrc\n", addr, rc));
1450
1451	pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1452	if (pPageRec)
1453	{
1454	if ( GCPhys == pPageRec->page.GCPhys
1455	&& (fFlags & X86_PTE_P))
1456	{
1457	STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1458	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1459	return VINF_SUCCESS;
1460	}
1461
1462	Log(("CSAMR3FlushPage: page %VGv has changed -> FLUSH (rc=%Vrc) (Phys: %VGp vs %VGp)\n", addr, rc, GCPhys, pPageRec->page.GCPhys));
1463
1464	STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushes, 1);
1465
1466	if (fRemovePage)
1467	csamRemovePageRecord(pVM, addr);
1468	else
1469	{
1470	CSAMMarkPage(pVM, addr, false);
1471	pPageRec->page.GCPhys = 0;
1472	pPageRec->page.fFlags = 0;
1473	rc = PGMGstGetPage(pVM, addr, &pPageRec->page.fFlags, &pPageRec->page.GCPhys);
1474	if (rc == VINF_SUCCESS)
1475	pPageRec->page.u64Hash = csamR3CalcPageHash(pVM, addr);
1476
1477	if (pPageRec->page.pBitmap == NULL)
1478	{
1479	pPageRec->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, CSAM_PAGE_BITMAP_SIZE);
1480	Assert(pPageRec->page.pBitmap);
1481	if (pPageRec->page.pBitmap == NULL)
1482	return VERR_NO_MEMORY;
1483	}
1484	else
1485	memset(pPageRec->page.pBitmap, 0, CSAM_PAGE_BITMAP_SIZE);
1486	}
1487
1488
1489	/*
1490	* Inform patch manager about the flush; no need to repeat the above check twice.
1491	*/
1492	PATMR3FlushPage(pVM, addr);
1493
1494	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1495	return VINF_SUCCESS;
1496	}
1497	else
1498	{
1499	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1500	return VWRN_CSAM_PAGE_NOT_FOUND;
1501	}
1502	}
1503
1504	/**
1505	* Notify CSAM of a page flush
1506	*
1507	* @returns VBox status code
1508	* @param pVM The VM to operate on.
1509	* @param addr GC address of the page to flush
1510	*/
1511	CSAMR3DECL(int) CSAMR3FlushPage(PVM pVM, RTGCPTR addr)
1512	{
1513	addr = addr & PAGE_BASE_GC_MASK;
1514	return csamFlushPage(pVM, addr, true /* remove page record */);
1515	}
1516
1517	/**
1518	* Remove a CSAM monitored page. Use with care!
1519	*
1520	* @returns VBox status code
1521	* @param pVM The VM to operate on.
1522	* @param addr GC address of the page to flush
1523	*/
1524	CSAMR3DECL(int) CSAMR3RemovePage(PVM pVM, RTGCPTR addr)
1525	{
1526	int rc = csamRemovePageRecord(pVM, addr);
1527	if (VBOX_SUCCESS(rc))
1528	PATMR3FlushPage(pVM, addr);
1529	return VINF_SUCCESS;
1530	}
1531
1532	/**
1533	* Check a page record in case a page has been changed
1534	*
1535	* @returns VBox status code. (trap handled or not)
1536	* @param pVM The VM to operate on.
1537	* @param pInstrGC GC instruction pointer
1538	*/
1539	int csamR3CheckPageRecord(PVM pVM, RTGCPTR pInstrGC)
1540	{
1541	PCSAMPAGEREC pPageRec;
1542	uint64_t u64hash;
1543
1544	pInstrGC = pInstrGC & PAGE_BASE_GC_MASK;
1545
1546	pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstrGC);
1547	if (pPageRec)
1548	{
1549	u64hash = csamR3CalcPageHash(pVM, pInstrGC);
1550	if (u64hash != pPageRec->page.u64Hash)
1551	csamFlushPage(pVM, pInstrGC, false /* don't remove page record */);
1552	}
1553	else
1554	return VWRN_CSAM_PAGE_NOT_FOUND;
1555
1556	return VINF_SUCCESS;
1557	}
1558
1559	/**
1560	* Returns monitor description based on CSAM tag
1561	*
1562	* @return description string
1563	* @param enmTag Owner tag
1564	*/
1565	const char *csamGetMonitorDescription(CSAMTAG enmTag)
1566	{
1567	if (enmTag == CSAM_TAG_PATM)
1568	return "CSAM-PATM self-modifying code monitor handler";
1569	else
1570	if (enmTag == CSAM_TAG_REM)
1571	return "CSAM-REM self-modifying code monitor handler";
1572	Assert(enmTag == CSAM_TAG_CSAM);
1573	return "CSAM self-modifying code monitor handler";
1574	}
1575
1576	/**
1577	* Adds page record to our lookup tree
1578	*
1579	* @returns CSAMPAGE ptr or NULL if failure
1580	* @param pVM The VM to operate on.
1581	* @param GCPtr Page address
1582	* @param enmTag Owner tag
1583	* @param fCode32 16 or 32 bits code
1584	* @param fMonitorInvalidation Monitor page invalidation flag
1585	*/
1586	static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTGCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation)
1587	{
1588	PCSAMPAGEREC pPage;
1589	int rc;
1590	bool ret;
1591
1592	Log(("New page record for %VGv\n", GCPtr & PAGE_BASE_GC_MASK));
1593
1594	pPage = (PCSAMPAGEREC)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, sizeof(CSAMPAGEREC));
1595	if (pPage == NULL)
1596	{
1597	AssertMsgFailed(("csamCreatePageRecord: Out of memory!!!!\n"));
1598	return NULL;
1599	}
1600	/* Round down to page boundary. */
1601	GCPtr = (GCPtr & PAGE_BASE_GC_MASK);
1602	pPage->Core.Key = (AVLPVKEY)GCPtr;
1603	pPage->page.pPageGC = GCPtr;
1604	pPage->page.fCode32 = fCode32;
1605	pPage->page.fMonitorInvalidation = fMonitorInvalidation;
1606	pPage->page.enmTag = enmTag;
1607	pPage->page.fMonitorActive = false;
1608	pPage->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, PAGE_SIZE/sizeof(uint8_t));
1609	rc = PGMGstGetPage(pVM, GCPtr, &pPage->page.fFlags, &pPage->page.GCPhys);
1610	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1611
1612	pPage->page.u64Hash = csamR3CalcPageHash(pVM, GCPtr);
1613	ret = RTAvlPVInsert(&pVM->csam.s.pPageTree, &pPage->Core);
1614	Assert(ret);
1615
1616	#ifdef CSAM_MONITOR_CODE_PAGES
1617	AssertRelease(!fInCSAMCodePageInvalidate);
1618
1619	switch (enmTag)
1620	{
1621	case CSAM_TAG_PATM:
1622	case CSAM_TAG_REM:
1623	#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1624	case CSAM_TAG_CSAM:
1625	#endif
1626	{
1627	int rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GCPtr, GCPtr + (PAGE_SIZE - 1) /* inclusive! */,
1628	(fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1629	csamGetMonitorDescription(enmTag));
1630	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VGv failed with %Vrc\n", GCPtr, rc));
1631	if (VBOX_FAILURE(rc))
1632	Log(("PGMR3HandlerVirtualRegisterEx for %VGv failed with %Vrc\n", GCPtr, rc));
1633
1634	/* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1635
1636	/* Prefetch it in case it's not there yet. */
1637	rc = PGMPrefetchPage(pVM, GCPtr);
1638	AssertRC(rc);
1639
1640	rc = PGMShwModifyPage(pVM, GCPtr, 1, 0, ~(uint64_t)X86_PTE_RW);
1641	Assert(rc == VINF_SUCCESS \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT);
1642
1643	pPage->page.fMonitorActive = true;
1644	STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1645	break;
1646	}
1647	default:
1648	break; /* to shut up GCC */
1649	}
1650
1651	Log(("csamCreatePageRecord %VGv HCPhys=%VGp\n", GCPtr, pPage->page.GCPhys));
1652
1653	#ifdef VBOX_WITH_STATISTICS
1654	switch (enmTag)
1655	{
1656	case CSAM_TAG_CSAM:
1657	STAM_COUNTER_INC(&pVM->csam.s.StatPageCSAM);
1658	break;
1659	case CSAM_TAG_PATM:
1660	STAM_COUNTER_INC(&pVM->csam.s.StatPagePATM);
1661	break;
1662	case CSAM_TAG_REM:
1663	STAM_COUNTER_INC(&pVM->csam.s.StatPageREM);
1664	break;
1665	default:
1666	break; /* to shut up GCC */
1667	}
1668	#endif
1669
1670	#endif
1671
1672	STAM_COUNTER_INC(&pVM->csam.s.StatNrPages);
1673	if (fMonitorInvalidation)
1674	STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1675
1676	return &pPage->page;
1677	}
1678
1679	/**
1680	* Monitors a code page (if not already monitored)
1681	*
1682	* @returns VBox status code
1683	* @param pVM The VM to operate on.
1684	* @param pPageAddrGC The page to monitor
1685	* @param enmTag Monitor tag
1686	*/
1687	CSAMR3DECL(int) CSAMR3MonitorPage(PVM pVM, RTGCPTR pPageAddrGC, CSAMTAG enmTag)
1688	{
1689	PCSAMPAGEREC pPageRec = NULL;
1690	int rc;
1691	bool fMonitorInvalidation;
1692
1693	/* Dirty pages must be handled before calling this function!. */
1694	Assert(!pVM->csam.s.cDirtyPages);
1695
1696	if (pVM->csam.s.fScanningStarted == false)
1697	return VINF_SUCCESS; /* too early */
1698
1699	pPageAddrGC &= PAGE_BASE_GC_MASK;
1700
1701	Log(("CSAMR3MonitorPage %VGv %d\n", pPageAddrGC, enmTag));
1702
1703	/** @todo implicit assumption */
1704	fMonitorInvalidation = (enmTag == CSAM_TAG_PATM);
1705
1706	pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1707	if (pPageRec == NULL)
1708	{
1709	uint64_t fFlags;
1710
1711	rc = PGMGstGetPage(pVM, pPageAddrGC, &fFlags, NULL);
1712	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1713	if ( rc == VINF_SUCCESS
1714	&& (fFlags & X86_PTE_US))
1715	{
1716	/* We don't care about user pages. */
1717	STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
1718	return VINF_SUCCESS;
1719	}
1720
1721	csamCreatePageRecord(pVM, pPageAddrGC, enmTag, true /* 32 bits code */, fMonitorInvalidation);
1722
1723	pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1724	Assert(pPageRec);
1725	}
1726	/** @todo reference count */
1727
1728	#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1729	Assert(pPageRec->page.fMonitorActive);
1730	#endif
1731
1732	#ifdef CSAM_MONITOR_CODE_PAGES
1733	if (!pPageRec->page.fMonitorActive)
1734	{
1735	Log(("CSAMR3MonitorPage: activate monitoring for %VGv\n", pPageAddrGC));
1736
1737	rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, pPageAddrGC, pPageAddrGC + (PAGE_SIZE - 1) /* inclusive! */,
1738	(fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1739	csamGetMonitorDescription(enmTag));
1740	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VGv failed with %Vrc\n", pPageAddrGC, rc));
1741	if (VBOX_FAILURE(rc))
1742	Log(("PGMR3HandlerVirtualRegisterEx for %VGv failed with %Vrc\n", pPageAddrGC, rc));
1743
1744	/* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1745
1746	/* Prefetch it in case it's not there yet. */
1747	rc = PGMPrefetchPage(pVM, pPageAddrGC);
1748	AssertRC(rc);
1749
1750	rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1751	Assert(rc == VINF_SUCCESS \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT);
1752
1753	STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1754
1755	pPageRec->page.fMonitorActive = true;
1756	pPageRec->page.fMonitorInvalidation = fMonitorInvalidation;
1757	}
1758	else
1759	if ( !pPageRec->page.fMonitorInvalidation
1760	&& fMonitorInvalidation)
1761	{
1762	Assert(pPageRec->page.fMonitorActive);
1763	PGMHandlerVirtualChangeInvalidateCallback(pVM, pPageRec->page.pPageGC, CSAMCodePageInvalidate);
1764	pPageRec->page.fMonitorInvalidation = true;
1765	STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1766
1767	/* Prefetch it in case it's not there yet. */
1768	rc = PGMPrefetchPage(pVM, pPageAddrGC);
1769	AssertRC(rc);
1770
1771	/* Make sure it's readonly. Page invalidation may have modified the attributes. */
1772	rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1773	Assert(rc == VINF_SUCCESS \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT);
1774	}
1775
1776	#if 0 /* def VBOX_STRICT -> very annoying) */
1777	if (pPageRec->page.fMonitorActive)
1778	{
1779	uint64_t fPageShw;
1780	RTHCPHYS GCPhys;
1781	rc = PGMShwGetPage(pVM, pPageAddrGC, &fPageShw, &GCPhys);
1782	// AssertMsg( (rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT)
1783	// \|\| !(fPageShw & X86_PTE_RW)
1784	// \|\| (pPageRec->page.GCPhys == 0), ("Shadow page flags for %VGv (%VHp) aren't readonly (%VX64)!!\n", pPageAddrGC, GCPhys, fPageShw));
1785	}
1786	#endif
1787
1788	if (pPageRec->page.GCPhys == 0)
1789	{
1790	/* Prefetch it in case it's not there yet. */
1791	rc = PGMPrefetchPage(pVM, pPageAddrGC);
1792	AssertRC(rc);
1793	/* The page was changed behind our back. It won't be made read-only until the next SyncCR3, so force it here. */
1794	rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1795	Assert(rc == VINF_SUCCESS \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT);
1796	}
1797	#endif /* CSAM_MONITOR_CODE_PAGES */
1798	return VINF_SUCCESS;
1799	}
1800
1801	/**
1802	* Removes a page record from our lookup tree
1803	*
1804	* @returns VBox status code
1805	* @param pVM The VM to operate on.
1806	* @param GCPtr Page address
1807	*/
1808	static int csamRemovePageRecord(PVM pVM, RTGCPTR GCPtr)
1809	{
1810	PCSAMPAGEREC pPageRec;
1811
1812	Log(("csamRemovePageRecord %VGv\n", GCPtr));
1813	pPageRec = (PCSAMPAGEREC)RTAvlPVRemove(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
1814
1815	if (pPageRec)
1816	{
1817	STAM_COUNTER_INC(&pVM->csam.s.StatNrRemovedPages);
1818
1819	#ifdef CSAM_MONITOR_CODE_PAGES
1820	if (pPageRec->page.fMonitorActive)
1821	{
1822	/* @todo -> this is expensive (cr3 reload)!!!
1823	* if this happens often, then reuse it instead!!!
1824	*/
1825	Assert(!fInCSAMCodePageInvalidate);
1826	STAM_COUNTER_DEC(&pVM->csam.s.StatPageMonitor);
1827	PGMHandlerVirtualDeregister(pVM, GCPtr);
1828	}
1829	if (pPageRec->page.enmTag == CSAM_TAG_PATM)
1830	{
1831	/* Make sure the recompiler flushes its cache as this page is no longer monitored. */
1832	STAM_COUNTER_INC(&pVM->csam.s.StatPageRemoveREMFlush);
1833	CPUMSetChangedFlags(pVM, CPUM_CHANGED_GLOBAL_TLB_FLUSH);
1834	}
1835	#endif
1836
1837	#ifdef VBOX_WITH_STATISTICS
1838	switch (pPageRec->page.enmTag)
1839	{
1840	case CSAM_TAG_CSAM:
1841	STAM_COUNTER_DEC(&pVM->csam.s.StatPageCSAM);
1842	break;
1843	case CSAM_TAG_PATM:
1844	STAM_COUNTER_DEC(&pVM->csam.s.StatPagePATM);
1845	break;
1846	case CSAM_TAG_REM:
1847	STAM_COUNTER_DEC(&pVM->csam.s.StatPageREM);
1848	break;
1849	default:
1850	break; /* to shut up GCC */
1851	}
1852	#endif
1853
1854	if (pPageRec->page.pBitmap) MMR3HeapFree(pPageRec->page.pBitmap);
1855	MMR3HeapFree(pPageRec);
1856	}
1857	else
1858	AssertFailed();
1859
1860	return VINF_SUCCESS;
1861	}
1862
1863	/**
1864	* Callback for delayed writes from non-EMT threads
1865	*
1866	* @param pVM VM Handle.
1867	* @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1868	* @param cbBuf How much it's reading/writing.
1869	*/
1870	static DECLCALLBACK(void) CSAMDelayedWriteHandler(PVM pVM, RTGCPTR GCPtr, size_t cbBuf)
1871	{
1872	int rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1873	AssertRC(rc);
1874	}
1875
1876	/**
1877	* #PF Handler callback for virtual access handler ranges.
1878	*
1879	* Important to realize that a physical page in a range can have aliases, and
1880	* for ALL and WRITE handlers these will also trigger.
1881	*
1882	* @returns VINF_SUCCESS if the handler have carried out the operation.
1883	* @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation.
1884	* @param pVM VM Handle.
1885	* @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1886	* @param pvPtr The HC mapping of that address.
1887	* @param pvBuf What the guest is reading/writing.
1888	* @param cbBuf How much it's reading/writing.
1889	* @param enmAccessType The access type.
1890	* @param pvUser User argument.
1891	*/
1892	static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void pvPtr, void pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser)
1893	{
1894	int rc;
1895
1896	Assert(enmAccessType == PGMACCESSTYPE_WRITE);
1897	Log(("CSAMCodePageWriteHandler: write to %VGv size=%d\n", GCPtr, cbBuf));
1898
1899	if (VM_IS_EMT(pVM))
1900	{
1901	rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1902	}
1903	else
1904	{
1905	/* Queue the write instead otherwise we'll get concurrency issues. */
1906	/** @note in theory not correct to let it write the data first before disabling a patch!
1907	* (if it writes the same data as the patch jump and we replace it with obsolete opcodes)
1908	*/
1909	Log(("CSAMCodePageWriteHandler: delayed write!\n"));
1910	rc = VMR3ReqCallEx(pVM, NULL, 0, VMREQFLAGS_NO_WAIT \| VMREQFLAGS_VOID,
1911	(PFNRT)CSAMDelayedWriteHandler, 3, pVM, GCPtr, cbBuf);
1912	}
1913	AssertRC(rc);
1914
1915	return VINF_PGM_HANDLER_DO_DEFAULT;
1916	}
1917
1918	/**
1919	* #PF Handler callback for invalidation of virtual access handler ranges.
1920	*
1921	* @param pVM VM Handle.
1922	* @param GCPtr The virtual address the guest has changed.
1923	*/
1924	static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr)
1925	{
1926	fInCSAMCodePageInvalidate = true;
1927	LogFlow(("CSAMCodePageInvalidate %VGv\n", GCPtr));
1928	/** @todo We can't remove the page (which unregisters the virtual handler) as we are called from a DoWithAll on the virtual handler tree. Argh. */
1929	csamFlushPage(pVM, GCPtr, false /* don't remove page! */);
1930	fInCSAMCodePageInvalidate = false;
1931	return VINF_SUCCESS;
1932	}
1933
1934	/**
1935	* Check if the current instruction has already been checked before
1936	*
1937	* @returns VBox status code. (trap handled or not)
1938	* @param pVM The VM to operate on.
1939	* @param pInstr Instruction pointer
1940	* @param pPage CSAM patch structure pointer
1941	*/
1942	bool csamIsCodeScanned(PVM pVM, RTGCPTR pInstr, PCSAMPAGE *pPage)
1943	{
1944	PCSAMPAGEREC pPageRec;
1945	uint32_t offset;
1946
1947	STAM_PROFILE_START(&pVM->csam.s.StatTimeCheckAddr, a);
1948
1949	offset = pInstr & PAGE_OFFSET_MASK;
1950	pInstr = pInstr & PAGE_BASE_GC_MASK;
1951
1952	Assert(pPage);
1953
1954	if (pPage && (pPage)->pPageGC == pInstr)
1955	{
1956	if ((pPage)->pBitmap == NULL \|\| ASMBitTest((pPage)->pBitmap, offset))
1957	{
1958	STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
1959	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1960	return true;
1961	}
1962	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1963	return false;
1964	}
1965
1966	pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstr);
1967	if (pPageRec)
1968	{
1969	if (pPage) *pPage= &pPageRec->page;
1970	if (pPageRec->page.pBitmap == NULL \|\| ASMBitTest(pPageRec->page.pBitmap, offset))
1971	{
1972	STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
1973	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1974	return true;
1975	}
1976	}
1977	else
1978	{
1979	if (pPage) *pPage = NULL;
1980	}
1981	STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1982	return false;
1983	}
1984
1985	/**
1986	* Mark an instruction in a page as scanned/not scanned
1987	*
1988	* @param pVM The VM to operate on.
1989	* @param pPage Patch structure pointer
1990	* @param pInstr Instruction pointer
1991	* @param opsize Instruction size
1992	* @param fScanned Mark as scanned or not
1993	*/
1994	static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTGCPTR pInstr, uint32_t opsize, bool fScanned)
1995	{
1996	LogFlow(("csamMarkCodeAsScanned %VGv opsize=%d\n", pInstr, opsize));
1997	CSAMMarkPage(pVM, pInstr, fScanned);
1998
1999	/** @todo should recreate empty bitmap if !fScanned */
2000	if (pPage->pBitmap == NULL)
2001	return;
2002
2003	if (fScanned)
2004	{
2005	// retn instructions can be scanned more than once
2006	if (ASMBitTest(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK) == 0)
2007	{
2008	pPage->uSize += opsize;
2009	STAM_COUNTER_ADD(&pVM->csam.s.StatNrInstr, 1);
2010	}
2011	if (pPage->uSize >= PAGE_SIZE)
2012	{
2013	Log(("Scanned full page (%VGv) -> free bitmap\n", pInstr & PAGE_BASE_GC_MASK));
2014	MMR3HeapFree(pPage->pBitmap);
2015	pPage->pBitmap = NULL;
2016	}
2017	else
2018	ASMBitSet(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2019	}
2020	else
2021	ASMBitClear(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2022	}
2023
2024	/**
2025	* Mark an instruction in a page as scanned/not scanned
2026	*
2027	* @returns VBox status code.
2028	* @param pVM The VM to operate on.
2029	* @param pInstr Instruction pointer
2030	* @param opsize Instruction size
2031	* @param fScanned Mark as scanned or not
2032	*/
2033	CSAMR3DECL(int) CSAMR3MarkCode(PVM pVM, RTGCPTR pInstr, uint32_t opsize, bool fScanned)
2034	{
2035	PCSAMPAGE pPage = 0;
2036
2037	Assert(!fScanned); /* other case not implemented. */
2038	Assert(!PATMIsPatchGCAddr(pVM, pInstr));
2039
2040	if (csamIsCodeScanned(pVM, pInstr, &pPage) == false)
2041	{
2042	Assert(fScanned == true); /* other case should not be possible */
2043	return VINF_SUCCESS;
2044	}
2045
2046	Log(("CSAMR3MarkCode: %VGv size=%d fScanned=%d\n", pInstr, opsize, fScanned));
2047	csamMarkCode(pVM, pPage, pInstr, opsize, fScanned);
2048	return VINF_SUCCESS;
2049	}
2050
2051
2052	/**
2053	* Scan and analyse code
2054	*
2055	* @returns VBox status code.
2056	* @param pVM The VM to operate on.
2057	* @param Sel selector
2058	* @param pHiddenSel The hidden selector register.
2059	* @param pInstrGC Instruction pointer
2060	*/
2061	CSAMR3DECL(int) CSAMR3CheckCodeEx(PVM pVM, RTSEL Sel, CPUMSELREGHID *pHiddenSel, RTGCPTR pInstrGC)
2062	{
2063	if (EMIsRawRing0Enabled(pVM) == false \|\| PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2064	{
2065	// No use
2066	return VINF_SUCCESS;
2067	}
2068
2069	if (CSAMIsEnabled(pVM))
2070	{
2071	X86EFLAGS fakeflags;
2072
2073	/* we're not in v86 mode here */
2074	fakeflags.u32 = 0;
2075
2076	bool fCode32 = SELMIsSelector32Bit(pVM, fakeflags, Sel, pHiddenSel);
2077
2078	//assuming 32 bits code for now
2079	Assert(fCode32); NOREF(fCode32);
2080
2081	pInstrGC = SELMToFlat(pVM, fakeflags, Sel, pHiddenSel, pInstrGC);
2082
2083	return CSAMR3CheckCode(pVM, pInstrGC);
2084	}
2085	return VINF_SUCCESS;
2086	}
2087
2088	/**
2089	* Scan and analyse code
2090	*
2091	* @returns VBox status code.
2092	* @param pVM The VM to operate on.
2093	* @param pInstrGC Instruction pointer (0:32 virtual address)
2094	*/
2095	CSAMR3DECL(int) CSAMR3CheckCode(PVM pVM, RTGCPTR pInstrGC)
2096	{
2097	int rc;
2098	PCSAMPAGE pPage = NULL;
2099
2100	if (EMIsRawRing0Enabled(pVM) == false \|\| PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2101	{
2102	// No use
2103	return VINF_SUCCESS;
2104	}
2105
2106	if (CSAMIsEnabled(pVM))
2107	{
2108	// Cache record for PATMGCVirtToHCVirt
2109	CSAMP2GLOOKUPREC cacheRec = {0};
2110
2111	STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2112	rc = csamAnalyseCallCodeStream(pVM, pInstrGC, pInstrGC, true /* 32 bits code */, CSAMR3AnalyseCallback, pPage, &cacheRec);
2113	STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2114	if (rc != VINF_SUCCESS)
2115	{
2116	Log(("csamAnalyseCodeStream failed with %d\n", rc));
2117	return rc;
2118	}
2119	}
2120	return VINF_SUCCESS;
2121	}
2122
2123	/**
2124	* Flush dirty code pages
2125	*
2126	* @returns VBox status code.
2127	* @param pVM The VM to operate on.
2128	*/
2129	static int csamR3FlushDirtyPages(PVM pVM)
2130	{
2131	STAM_PROFILE_START(&pVM->csam.s.StatFlushDirtyPages, a);
2132
2133	for (uint32_t i=0;i<pVM->csam.s.cDirtyPages;i++)
2134	{
2135	int rc;
2136	PCSAMPAGEREC pPageRec;
2137	RTGCPTR GCPtr = pVM->csam.s.pvDirtyBasePage[i];
2138
2139	GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2140
2141	/* Notify the recompiler that this page has been changed. */
2142	REMR3NotifyCodePageChanged(pVM, GCPtr);
2143
2144	/* Enable write protection again. (use the fault address as it might be an alias) */
2145	rc = PGMShwModifyPage(pVM, pVM->csam.s.pvDirtyFaultPage[i], 1, 0, ~(uint64_t)X86_PTE_RW);
2146	Assert(rc == VINF_SUCCESS \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT);
2147
2148	Log(("CSAMR3FlushDirtyPages: flush %VGv (modifypage rc=%Vrc)\n", pVM->csam.s.pvDirtyBasePage[i], rc));
2149
2150	pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
2151	if (pPageRec && pPageRec->page.enmTag == CSAM_TAG_REM)
2152	{
2153	uint64_t fFlags;
2154
2155	rc = PGMGstGetPage(pVM, GCPtr, &fFlags, NULL);
2156	AssertMsg(VBOX_SUCCESS(rc) \|\| rc == VERR_PAGE_NOT_PRESENT \|\| rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
2157	if ( rc == VINF_SUCCESS
2158	&& (fFlags & X86_PTE_US))
2159	{
2160	/* We don't care about user pages. */
2161	csamRemovePageRecord(pVM, GCPtr);
2162	STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
2163	}
2164	}
2165	}
2166	pVM->csam.s.cDirtyPages = 0;
2167	STAM_PROFILE_STOP(&pVM->csam.s.StatFlushDirtyPages, a);
2168	return VINF_SUCCESS;
2169	}
2170
2171	/**
2172	* Flush potential new code pages
2173	*
2174	* @returns VBox status code.
2175	* @param pVM The VM to operate on.
2176	*/
2177	static int csamR3FlushCodePages(PVM pVM)
2178	{
2179	for (uint32_t i=0;i<pVM->csam.s.cPossibleCodePages;i++)
2180	{
2181	RTGCPTR GCPtr = pVM->csam.s.pvPossibleCodePage[i];
2182
2183	GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2184
2185	Log(("csamR3FlushCodePages: %VGv\n", GCPtr));
2186	PGMShwSetPage(pVM, GCPtr, 1, 0);
2187	/* Resync the page to make sure instruction fetch will fault */
2188	CSAMMarkPage(pVM, GCPtr, false);
2189	}
2190	pVM->csam.s.cPossibleCodePages = 0;
2191	return VINF_SUCCESS;
2192	}
2193
2194	/**
2195	* Perform any pending actions
2196	*
2197	* @returns VBox status code.
2198	* @param pVM The VM to operate on.
2199	*/
2200	CSAMR3DECL(int) CSAMR3DoPendingAction(PVM pVM)
2201	{
2202	csamR3FlushDirtyPages(pVM);
2203	csamR3FlushCodePages(pVM);
2204
2205	VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
2206	return VINF_SUCCESS;
2207	}
2208
2209	/**
2210	* Analyse interrupt and trap gates
2211	*
2212	* @returns VBox status code.
2213	* @param pVM The VM to operate on.
2214	* @param iGate Start gate
2215	* @param cGates Number of gates to check
2216	*/
2217	CSAMR3DECL(int) CSAMR3CheckGates(PVM pVM, uint32_t iGate, uint32_t cGates)
2218	{
2219	uint16_t cbIDT;
2220	RTGCPTR GCPtrIDT = CPUMGetGuestIDTR(pVM, &cbIDT);
2221	uint32_t iGateEnd;
2222	uint32_t maxGates;
2223	VBOXIDTE aIDT[256];
2224	PVBOXIDTE pGuestIdte;
2225	int rc;
2226
2227	if (EMIsRawRing0Enabled(pVM) == false)
2228	{
2229	/* Enabling interrupt gates only works when raw ring 0 is enabled. */
2230	//AssertFailed();
2231	return VINF_SUCCESS;
2232	}
2233
2234	/* We only check all gates once during a session */
2235	if ( !pVM->csam.s.fGatesChecked
2236	&& cGates != 256)
2237	return VINF_SUCCESS; /* too early */
2238
2239	/* We only check all gates once during a session */
2240	if ( pVM->csam.s.fGatesChecked
2241	&& cGates != 1)
2242	return VINF_SUCCESS; /* ignored */
2243
2244	Assert(cGates <= 256);
2245	if (!GCPtrIDT \|\| cGates > 256)
2246	return VERR_INVALID_PARAMETER;
2247
2248	if (cGates != 1)
2249	pVM->csam.s.fGatesChecked = true;
2250
2251	/* Determine valid upper boundary. */
2252	maxGates = (cbIDT+1) / sizeof(VBOXIDTE);
2253	Assert(iGate < maxGates);
2254	if (iGate > maxGates)
2255	return VERR_INVALID_PARAMETER;
2256
2257	if (iGate + cGates > maxGates)
2258	cGates = maxGates - iGate;
2259
2260	GCPtrIDT = GCPtrIDT + iGate * sizeof(VBOXIDTE);
2261	iGateEnd = iGate + cGates;
2262
2263	STAM_PROFILE_START(&pVM->csam.s.StatCheckGates, a);
2264
2265	/*
2266	* Get IDT entries.
2267	*/
2268	if (PAGE_ADDRESS(GCPtrIDT) == PAGE_ADDRESS(GCPtrIDT+cGates*sizeof(VBOXIDTE)))
2269	{
2270	/* Just convert the IDT address to a HC pointer. The whole IDT fits in one page. */
2271	rc = PGMPhysGCPtr2HCPtr(pVM, GCPtrIDT, (PRTHCPTR)&pGuestIdte);
2272	if (VBOX_FAILURE(rc))
2273	{
2274	AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2275	STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2276	return rc;
2277	}
2278	}
2279	else
2280	{
2281	/* Slow method when it crosses a page boundary. */
2282	rc = PGMPhysReadGCPtr(pVM, aIDT, GCPtrIDT, cGates*sizeof(VBOXIDTE));
2283	if (VBOX_FAILURE(rc))
2284	{
2285	AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2286	STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2287	return rc;
2288	}
2289	pGuestIdte = &aIDT[0];
2290	}
2291
2292	for (/iGate/; iGate<iGateEnd; iGate++, pGuestIdte++)
2293	{
2294	Assert(TRPMR3GetGuestTrapHandler(pVM, iGate) == TRPM_INVALID_HANDLER);
2295
2296	if ( pGuestIdte->Gen.u1Present
2297	&& (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32 \|\| pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_INT_32)
2298	&& (pGuestIdte->Gen.u2DPL == 3 \|\| pGuestIdte->Gen.u2DPL == 0)
2299	)
2300	{
2301	RTGCPTR pHandler;
2302	CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2303	PCSAMPAGE pPage = NULL;
2304	X86EFLAGS fakeflags;
2305	SELMSELINFO selInfo;
2306
2307	/* we're not in v86 mode here */
2308	fakeflags.u32 = 0;
2309
2310	pHandler = (pGuestIdte->Gen.u16OffsetHigh << 16) \| pGuestIdte->Gen.u16OffsetLow;
2311	pHandler = SELMToFlat(pVM, fakeflags, pGuestIdte->Gen.u16SegSel, 0, pHandler);
2312
2313	rc = SELMR3GetSelectorInfo(pVM, pGuestIdte->Gen.u16SegSel, &selInfo);
2314	if ( VBOX_FAILURE(rc)
2315	\|\| selInfo.GCPtrBase != 0
2316	\|\| selInfo.cbLimit != ~0U
2317	)
2318	{
2319	/* Refuse to patch a handler whose idt cs selector isn't wide open. */
2320	Log(("CSAMCheckGates: check gate %d failed due to rc %Vrc GCPtrBase=%VGv limit=%x\n", iGate, rc, selInfo.GCPtrBase, selInfo.cbLimit));
2321	continue;
2322	}
2323
2324
2325	if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2326	{
2327	Log(("CSAMCheckGates: check trap gate %d at %04X:%08X (flat %VGv)\n", iGate, pGuestIdte->Gen.u16SegSel, (pGuestIdte->Gen.u16OffsetHigh << 16) \| pGuestIdte->Gen.u16OffsetLow, pHandler));
2328	}
2329	else
2330	{
2331	Log(("CSAMCheckGates: check interrupt gate %d at %04X:%08X (flat %VGv)\n", iGate, pGuestIdte->Gen.u16SegSel, (pGuestIdte->Gen.u16OffsetHigh << 16) \| pGuestIdte->Gen.u16OffsetLow, pHandler));
2332	}
2333
2334	STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2335	rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2336	STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2337	if (rc != VINF_SUCCESS)
2338	{
2339	Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2340	continue;
2341	}
2342	/* OpenBSD guest specific patch test. */
2343	if (iGate >= 0x20)
2344	{
2345	PCPUMCTX pCtx;
2346	DISCPUSTATE cpu;
2347	RTGCUINTPTR aOpenBsdPushCSOffset[3] = {0x03, /* OpenBSD 3.7 & 3.8 */
2348	0x2B, /* OpenBSD 4.0 installation ISO */
2349	0x2F}; /* OpenBSD 4.0 after install */
2350
2351	rc = CPUMQueryGuestCtxPtr(pVM, &pCtx);
2352	AssertRC(rc); /* can't fail */
2353
2354	for (unsigned i=0;i<ELEMENTS(aOpenBsdPushCSOffset);i++)
2355	{
2356	rc = CPUMR3DisasmInstrCPU(pVM, pCtx, pHandler - aOpenBsdPushCSOffset[i], &cpu, NULL);
2357	if ( rc == VINF_SUCCESS
2358	&& cpu.pCurInstr->opcode == OP_PUSH
2359	&& cpu.pCurInstr->param1 == OP_PARM_REG_CS)
2360	{
2361	rc = PATMR3InstallPatch(pVM, pHandler - aOpenBsdPushCSOffset[i], PATMFL_CODE32 \| PATMFL_GUEST_SPECIFIC);
2362	if (VBOX_SUCCESS(rc))
2363	Log(("Installed OpenBSD interrupt handler prefix instruction (push cs) patch\n"));
2364	}
2365	}
2366	}
2367
2368	/* Trap gates and certain interrupt gates. */
2369	uint32_t fPatchFlags = PATMFL_CODE32 \| PATMFL_IDTHANDLER;
2370
2371	if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2372	fPatchFlags \|= PATMFL_TRAPHANDLER;
2373	else
2374	fPatchFlags \|= PATMFL_INTHANDLER;
2375
2376	switch (iGate) {
2377	case 8:
2378	case 10:
2379	case 11:
2380	case 12:
2381	case 13:
2382	case 14:
2383	case 17:
2384	fPatchFlags \|= PATMFL_TRAPHANDLER_WITH_ERRORCODE;
2385	break;
2386	default:
2387	/* No error code. */
2388	break;
2389	}
2390
2391	Log(("Installing %s gate handler for 0x%X at %VGv\n", (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32) ? "trap" : "intr", iGate, pHandler));
2392
2393	rc = PATMR3InstallPatch(pVM, pHandler, fPatchFlags);
2394	if (VBOX_SUCCESS(rc) \|\| rc == VERR_PATM_ALREADY_PATCHED)
2395	{
2396	Log(("Gate handler 0x%X is SAFE!\n", iGate));
2397
2398	RTGCPTR pNewHandlerGC = PATMR3QueryPatchGCPtr(pVM, pHandler);
2399	if (pNewHandlerGC)
2400	{
2401	rc = TRPMR3SetGuestTrapHandler(pVM, iGate, pNewHandlerGC);
2402	if (VBOX_FAILURE(rc))
2403	Log(("TRPMR3SetGuestTrapHandler %d failed with %Vrc\n", iGate, rc));
2404	}
2405	}
2406	}
2407	} /* for */
2408	STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2409	return VINF_SUCCESS;
2410	}
2411
2412	/**
2413	* Query CSAM state (enabled/disabled)
2414	*
2415	* @returns 0 - disabled, 1 - enabled
2416	* @param pVM The VM to operate on.
2417	*/
2418	CSAMR3DECL(int) CSAMR3IsEnabled(PVM pVM)
2419	{
2420	return pVM->fCSAMEnabled;
2421	}
2422
2423	#ifdef VBOX_WITH_DEBUGGER
2424	/**
2425	* The '.csamoff' command.
2426	*
2427	* @returns VBox status.
2428	* @param pCmd Pointer to the command descriptor (as registered).
2429	* @param pCmdHlp Pointer to command helper functions.
2430	* @param pVM Pointer to the current VM (if any).
2431	* @param paArgs Pointer to (readonly) array of arguments.
2432	* @param cArgs Number of arguments in the array.
2433	*/
2434	static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2435	{
2436	/*
2437	* Validate input.
2438	*/
2439	if (!pVM)
2440	return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2441
2442	CSAMDisableScanning(pVM);
2443	return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning disabled\n");
2444	}
2445
2446	/**
2447	* The '.csamon' command.
2448	*
2449	* @returns VBox status.
2450	* @param pCmd Pointer to the command descriptor (as registered).
2451	* @param pCmdHlp Pointer to command helper functions.
2452	* @param pVM Pointer to the current VM (if any).
2453	* @param paArgs Pointer to (readonly) array of arguments.
2454	* @param cArgs Number of arguments in the array.
2455	*/
2456	static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2457	{
2458	/*
2459	* Validate input.
2460	*/
2461	if (!pVM)
2462	return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2463
2464	CSAMEnableScanning(pVM);
2465	return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning enabled\n");
2466	}
2467	#endif

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source: vbox/trunk/src/VBox/VMM/PATM/CSAM.cpp@ 1995

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