VirtualBox

source: vbox/trunk/src/VBox/VMM/PATM/CSAM.cpp@ 6796

Last change on this file since 6796 was 5999, checked in by vboxsync, 17 years ago

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1/* $Id: CSAM.cpp 5999 2007-12-07 15:05:06Z vboxsync $ */
2/** @file
3 * CSAM - Guest OS Code Scanning and Analysis Manager
4 */
5
6/*
7 * Copyright (C) 2006-2007 innotek 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 (GPL) as published by the Free Software
13 * Foundation, in version 2 as it comes in the "COPYING" file of the
14 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16 */
17
18/*******************************************************************************
19* Header Files *
20*******************************************************************************/
21#define LOG_GROUP LOG_GROUP_CSAM
22#include <VBox/cpum.h>
23#include <VBox/stam.h>
24#include <VBox/patm.h>
25#include <VBox/csam.h>
26#include <VBox/cpumdis.h>
27#include <VBox/pgm.h>
28#include <VBox/iom.h>
29#include <VBox/sup.h>
30#include <VBox/mm.h>
31#include <VBox/em.h>
32#include <VBox/rem.h>
33#include <VBox/selm.h>
34#include <VBox/trpm.h>
35#include <VBox/cfgm.h>
36#include <VBox/param.h>
37#include <iprt/avl.h>
38#include <iprt/asm.h>
39#include <iprt/thread.h>
40#include "CSAMInternal.h"
41#include <VBox/vm.h>
42#include <VBox/dbg.h>
43#include <VBox/err.h>
44#include <VBox/ssm.h>
45#include <VBox/log.h>
46#include <iprt/assert.h>
47#include <iprt/string.h>
48#include <VBox/dis.h>
49#include <VBox/disopcode.h>
50#include <stdlib.h>
51#include <stdio.h>
52
53
54/* Enabled by default */
55#define CSAM_ENABLE
56
57/* Enable to monitor code pages for self-modifying code. */
58#define CSAM_MONITOR_CODE_PAGES
59/* Enable to monitor all scanned pages
60#define CSAM_MONITOR_CSAM_CODE_PAGES */
61/* Enable to scan beyond ret instructions.
62#define CSAM_ANALYSE_BEYOND_RET */
63
64/*******************************************************************************
65* Internal Functions *
66*******************************************************************************/
67static DECLCALLBACK(int) csamr3Save(PVM pVM, PSSMHANDLE pSSM);
68static DECLCALLBACK(int) csamr3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version);
69static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser);
70static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr);
71
72bool csamIsCodeScanned(PVM pVM, RTGCPTR pInstr, PCSAMPAGE *pPage);
73int csamR3CheckPageRecord(PVM pVM, RTGCPTR pInstr);
74static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTGCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation = false);
75static int csamRemovePageRecord(PVM pVM, RTGCPTR GCPtr);
76static int csamReinit(PVM pVM);
77static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTGCPTR pInstr, uint32_t opsize, bool fScanned);
78static int csamAnalyseCodeStream(PVM pVM, GCPTRTYPE(uint8_t *) pInstrGC, GCPTRTYPE(uint8_t *) pCurInstrGC, bool fCode32,
79 PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec);
80
81/** @todo Temporary for debugging. */
82static bool fInCSAMCodePageInvalidate = false;
83
84/*******************************************************************************
85* Global Variables *
86*******************************************************************************/
87#ifdef VBOX_WITH_DEBUGGER
88static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult);
89static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult);
90
91/** Command descriptors. */
92static const DBGCCMD g_aCmds[] =
93{
94 /* pszCmd, cArgsMin, cArgsMax, paArgDesc, cArgDescs, pResultDesc, fFlags, pfnHandler pszSyntax, ....pszDescription */
95 { "csamon", 0, 0, NULL, 0, NULL, 0, csamr3CmdOn, "", "Enable CSAM code scanning." },
96 { "csamoff", 0, 0, NULL, 0, NULL, 0, csamr3CmdOff, "", "Disable CSAM code scanning." },
97};
98#endif
99
100
101/**
102 * Initializes the CSAM.
103 *
104 * @returns VBox status code.
105 * @param pVM The VM to operate on.
106 */
107CSAMR3DECL(int) CSAMR3Init(PVM pVM)
108{
109 int rc;
110
111 LogFlow(("CSAMR3Init\n"));
112
113 /* Allocate bitmap for the page directory. */
114 rc = MMR3HyperAllocOnceNoRel(pVM, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR), 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDBitmapHC);
115 AssertRCReturn(rc, rc);
116 rc = MMR3HyperAllocOnceNoRel(pVM, CSAM_PGDIRBMP_CHUNKS*sizeof(RTGCPTR), 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDGCBitmapHC);
117 AssertRCReturn(rc, rc);
118 pVM->csam.s.pPDBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDGCBitmapHC);
119 pVM->csam.s.pPDHCBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC);
120
121 rc = csamReinit(pVM);
122 AssertRCReturn(rc, rc);
123
124 /*
125 * Register save and load state notificators.
126 */
127 rc = SSMR3RegisterInternal(pVM, "CSAM", 0, CSAM_SSM_VERSION, sizeof(pVM->csam.s) + PAGE_SIZE*16,
128 NULL, csamr3Save, NULL,
129 NULL, csamr3Load, NULL);
130 AssertRCReturn(rc, rc);
131
132 STAM_REG(pVM, &pVM->csam.s.StatNrTraps, STAMTYPE_COUNTER, "/CSAM/PageTraps", STAMUNIT_OCCURENCES, "The number of CSAM page traps.");
133 STAM_REG(pVM, &pVM->csam.s.StatDangerousWrite, STAMTYPE_COUNTER, "/CSAM/DangerousWrites", STAMUNIT_OCCURENCES, "The number of dangerous writes that cause a context switch.");
134
135 STAM_REG(pVM, &pVM->csam.s.StatNrPageNPHC, STAMTYPE_COUNTER, "/CSAM/HC/PageNotPresent", STAMUNIT_OCCURENCES, "The number of CSAM pages marked not present.");
136 STAM_REG(pVM, &pVM->csam.s.StatNrPageNPGC, STAMTYPE_COUNTER, "/CSAM/GC/PageNotPresent", STAMUNIT_OCCURENCES, "The number of CSAM pages marked not present.");
137 STAM_REG(pVM, &pVM->csam.s.StatNrPages, STAMTYPE_COUNTER, "/CSAM/PageRec/AddedRW", STAMUNIT_OCCURENCES, "The number of CSAM page records (RW monitoring).");
138 STAM_REG(pVM, &pVM->csam.s.StatNrPagesInv, STAMTYPE_COUNTER, "/CSAM/PageRec/AddedRWI", STAMUNIT_OCCURENCES, "The number of CSAM page records (RW & invalidation monitoring).");
139 STAM_REG(pVM, &pVM->csam.s.StatNrRemovedPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Removed", STAMUNIT_OCCURENCES, "The number of removed CSAM page records.");
140 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.");
141
142 STAM_REG(pVM, &pVM->csam.s.StatNrPatchPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Patch", STAMUNIT_OCCURENCES, "The number of CSAM patch page records.");
143 STAM_REG(pVM, &pVM->csam.s.StatNrUserPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Ignore/User", STAMUNIT_OCCURENCES, "The number of CSAM user page records (ignored).");
144 STAM_REG(pVM, &pVM->csam.s.StatPagePATM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/PATM", STAMUNIT_OCCURENCES, "The number of PATM page records.");
145 STAM_REG(pVM, &pVM->csam.s.StatPageCSAM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/CSAM", STAMUNIT_OCCURENCES, "The number of CSAM page records.");
146 STAM_REG(pVM, &pVM->csam.s.StatPageREM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/REM", STAMUNIT_OCCURENCES, "The number of REM page records.");
147 STAM_REG(pVM, &pVM->csam.s.StatPageMonitor, STAMTYPE_COUNTER, "/CSAM/PageRec/Monitored", STAMUNIT_OCCURENCES, "The number of monitored pages.");
148
149 STAM_REG(pVM, &pVM->csam.s.StatCodePageModified, STAMTYPE_COUNTER, "/CSAM/Monitor/DirtyPage", STAMUNIT_OCCURENCES, "The number of code page modifications.");
150
151 STAM_REG(pVM, &pVM->csam.s.StatNrFlushes, STAMTYPE_COUNTER, "/CSAM/PageFlushes", STAMUNIT_OCCURENCES, "The number of CSAM page flushes.");
152 STAM_REG(pVM, &pVM->csam.s.StatNrFlushesSkipped, STAMTYPE_COUNTER, "/CSAM/PageFlushesSkipped", STAMUNIT_OCCURENCES, "The number of CSAM page flushes that were skipped.");
153 STAM_REG(pVM, &pVM->csam.s.StatNrKnownPagesHC, STAMTYPE_COUNTER, "/CSAM/HC/KnownPageRecords", STAMUNIT_OCCURENCES, "The number of known CSAM page records.");
154 STAM_REG(pVM, &pVM->csam.s.StatNrKnownPagesGC, STAMTYPE_COUNTER, "/CSAM/GC/KnownPageRecords", STAMUNIT_OCCURENCES, "The number of known CSAM page records.");
155 STAM_REG(pVM, &pVM->csam.s.StatNrInstr, STAMTYPE_COUNTER, "/CSAM/ScannedInstr", STAMUNIT_OCCURENCES, "The number of scanned instructions.");
156 STAM_REG(pVM, &pVM->csam.s.StatNrBytesRead, STAMTYPE_COUNTER, "/CSAM/BytesRead", STAMUNIT_OCCURENCES, "The number of bytes read for scanning.");
157 STAM_REG(pVM, &pVM->csam.s.StatNrOpcodeRead, STAMTYPE_COUNTER, "/CSAM/OpcodeBytesRead", STAMUNIT_OCCURENCES, "The number of opcode bytes read by the recompiler.");
158
159 STAM_REG(pVM, &pVM->csam.s.StatBitmapAlloc, STAMTYPE_COUNTER, "/CSAM/Alloc/PageBitmap", STAMUNIT_OCCURENCES, "The number of page bitmap allocations.");
160
161 STAM_REG(pVM, &pVM->csam.s.StatInstrCacheHit, STAMTYPE_COUNTER, "/CSAM/Cache/Hit", STAMUNIT_OCCURENCES, "The number of dangerous instruction cache hits.");
162 STAM_REG(pVM, &pVM->csam.s.StatInstrCacheMiss, STAMTYPE_COUNTER, "/CSAM/Cache/Miss", STAMUNIT_OCCURENCES, "The number of dangerous instruction cache misses.");
163
164 STAM_REG(pVM, &pVM->csam.s.StatScanNextFunction, STAMTYPE_COUNTER, "/CSAM/Function/Scan/Success", STAMUNIT_OCCURENCES, "The number of found functions beyond the ret border.");
165 STAM_REG(pVM, &pVM->csam.s.StatScanNextFunctionFailed, STAMTYPE_COUNTER, "/CSAM/Function/Scan/Failed", STAMUNIT_OCCURENCES, "The number of refused functions beyond the ret border.");
166
167 STAM_REG(pVM, &pVM->csam.s.StatTime, STAMTYPE_PROFILE, "/PROF/CSAM/Scan", STAMUNIT_TICKS_PER_CALL, "Scanning overhead.");
168 STAM_REG(pVM, &pVM->csam.s.StatTimeCheckAddr, STAMTYPE_PROFILE, "/PROF/CSAM/CheckAddr", STAMUNIT_TICKS_PER_CALL, "Address check overhead.");
169 STAM_REG(pVM, &pVM->csam.s.StatTimeAddrConv, STAMTYPE_PROFILE, "/PROF/CSAM/AddrConv", STAMUNIT_TICKS_PER_CALL, "Address conversion overhead.");
170 STAM_REG(pVM, &pVM->csam.s.StatTimeFlushPage, STAMTYPE_PROFILE, "/PROF/CSAM/FlushPage", STAMUNIT_TICKS_PER_CALL, "Page flushing overhead.");
171 STAM_REG(pVM, &pVM->csam.s.StatTimeDisasm, STAMTYPE_PROFILE, "/PROF/CSAM/Disasm", STAMUNIT_TICKS_PER_CALL, "Disassembly overhead.");
172 STAM_REG(pVM, &pVM->csam.s.StatFlushDirtyPages, STAMTYPE_PROFILE, "/PROF/CSAM/FlushDirtyPage", STAMUNIT_TICKS_PER_CALL, "Dirty page flushing overhead.");
173 STAM_REG(pVM, &pVM->csam.s.StatCheckGates, STAMTYPE_PROFILE, "/PROF/CSAM/CheckGates", STAMUNIT_TICKS_PER_CALL, "CSAMR3CheckGates overhead.");
174
175 /*
176 * Check CFGM option and enable/disable CSAM.
177 */
178 bool fEnabled;
179 rc = CFGMR3QueryBool(CFGMR3GetRoot(pVM), "CSAMEnabled", &fEnabled);
180 if (VBOX_FAILURE(rc))
181#ifdef CSAM_ENABLE
182 fEnabled = true;
183#else
184 fEnabled = false;
185#endif
186 if (fEnabled)
187 CSAMEnableScanning(pVM);
188
189#ifdef VBOX_WITH_DEBUGGER
190 /*
191 * Debugger commands.
192 */
193 static bool fRegisteredCmds = false;
194 if (!fRegisteredCmds)
195 {
196 int rc = DBGCRegisterCommands(&g_aCmds[0], ELEMENTS(g_aCmds));
197 if (VBOX_SUCCESS(rc))
198 fRegisteredCmds = true;
199 }
200#endif
201
202 return VINF_SUCCESS;
203}
204
205/**
206 * (Re)initializes CSAM
207 *
208 * @param pVM The VM.
209 */
210static int csamReinit(PVM pVM)
211{
212 /*
213 * Assert alignment and sizes.
214 */
215 AssertRelease(!(RT_OFFSETOF(VM, csam.s) & 31));
216 AssertRelease(sizeof(pVM->csam.s) <= sizeof(pVM->csam.padding));
217
218 /*
219 * Setup any fixed pointers and offsets.
220 */
221 pVM->csam.s.offVM = RT_OFFSETOF(VM, patm);
222
223 pVM->csam.s.fGatesChecked = false;
224 pVM->csam.s.fScanningStarted = false;
225
226 VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
227 pVM->csam.s.cDirtyPages = 0;
228 /* not necessary */
229 memset(pVM->csam.s.pvDirtyBasePage, 0, sizeof(pVM->csam.s.pvDirtyBasePage));
230 memset(pVM->csam.s.pvDirtyFaultPage, 0, sizeof(pVM->csam.s.pvDirtyFaultPage));
231
232 memset(&pVM->csam.s.aDangerousInstr, 0, sizeof(pVM->csam.s.aDangerousInstr));
233 pVM->csam.s.cDangerousInstr = 0;
234 pVM->csam.s.iDangerousInstr = 0;
235
236 memset(pVM->csam.s.pvCallInstruction, 0, sizeof(pVM->csam.s.pvCallInstruction));
237 pVM->csam.s.iCallInstruction = 0;
238
239 /** @note never mess with the pgdir bitmap here! */
240 return VINF_SUCCESS;
241}
242
243/**
244 * Applies relocations to data and code managed by this
245 * component. This function will be called at init and
246 * whenever the VMM need to relocate itself inside the GC.
247 *
248 * The csam will update the addresses used by the switcher.
249 *
250 * @param pVM The VM.
251 * @param offDelta Relocation delta.
252 */
253CSAMR3DECL(void) CSAMR3Relocate(PVM pVM, RTGCINTPTR offDelta)
254{
255 if (offDelta)
256 {
257 /* Adjust pgdir and page bitmap pointers. */
258 pVM->csam.s.pPDBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDGCBitmapHC);
259 pVM->csam.s.pPDHCBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC);
260
261 for(int i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
262 {
263 if (pVM->csam.s.pPDGCBitmapHC[i])
264 {
265 pVM->csam.s.pPDGCBitmapHC[i] += offDelta;
266 }
267 }
268 }
269 return;
270}
271
272/**
273 * Terminates the csam.
274 *
275 * Termination means cleaning up and freeing all resources,
276 * the VM it self is at this point powered off or suspended.
277 *
278 * @returns VBox status code.
279 * @param pVM The VM to operate on.
280 */
281CSAMR3DECL(int) CSAMR3Term(PVM pVM)
282{
283 int rc;
284
285 rc = CSAMR3Reset(pVM);
286 AssertRC(rc);
287
288 /* @todo triggers assertion in MMHyperFree */
289#if 0
290 for(int i=0;i<CSAM_PAGEBMP_CHUNKS;i++)
291 {
292 if (pVM->csam.s.pPDBitmapHC[i])
293 MMHyperFree(pVM, pVM->csam.s.pPDBitmapHC[i]);
294 }
295#endif
296
297 return VINF_SUCCESS;
298}
299
300/**
301 * CSAM reset callback.
302 *
303 * @returns VBox status code.
304 * @param pVM The VM which is reset.
305 */
306CSAMR3DECL(int) CSAMR3Reset(PVM pVM)
307{
308 /* Clear page bitmaps. */
309 for(int i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
310 {
311 if (pVM->csam.s.pPDBitmapHC[i])
312 {
313 Assert((CSAM_PAGE_BITMAP_SIZE& 3) == 0);
314 ASMMemZero32(pVM->csam.s.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
315 }
316 }
317
318 /* Remove all CSAM page records. */
319 while(true)
320 {
321 PCSAMPAGEREC pPageRec = (PCSAMPAGEREC)RTAvlPVGetBestFit(&pVM->csam.s.pPageTree, 0, true);
322 if (pPageRec)
323 {
324 csamRemovePageRecord(pVM, pPageRec->page.pPageGC);
325 }
326 else
327 break;
328 }
329 Assert(!pVM->csam.s.pPageTree);
330
331 csamReinit(pVM);
332
333 return VINF_SUCCESS;
334}
335
336#define CSAM_SUBTRACT_PTR(a, b) *(uintptr_t *)&(a) = (uintptr_t)(a) - (uintptr_t)(b)
337#define CSAM_ADD_PTR(a, b) *(uintptr_t *)&(a) = (uintptr_t)(a) + (uintptr_t)(b)
338
339
340/**
341 * Callback function for RTAvlPVDoWithAll
342 *
343 * Counts the number of records in the tree
344 *
345 * @returns VBox status code.
346 * @param pNode Current node
347 * @param pcPatches Pointer to patch counter
348 */
349static DECLCALLBACK(int) CountRecord(PAVLPVNODECORE pNode, void *pcPatches)
350{
351 *(uint32_t *)pcPatches = *(uint32_t *)pcPatches + 1;
352 return VINF_SUCCESS;
353}
354
355/**
356 * Callback function for RTAvlPVDoWithAll
357 *
358 * Saves the state of the page record
359 *
360 * @returns VBox status code.
361 * @param pNode Current node
362 * @param pVM1 VM Handle
363 */
364static DECLCALLBACK(int) SavePageState(PAVLPVNODECORE pNode, void *pVM1)
365{
366 PVM pVM = (PVM)pVM1;
367 PCSAMPAGEREC pPage = (PCSAMPAGEREC)pNode;
368 CSAMPAGEREC page = *pPage;
369 PSSMHANDLE pSSM = pVM->csam.s.savedstate.pSSM;
370 int rc;
371
372 /* Save the page record itself */
373 rc = SSMR3PutMem(pSSM, &page, sizeof(page));
374 AssertRCReturn(rc, rc);
375
376 if (page.page.pBitmap)
377 {
378 rc = SSMR3PutMem(pSSM, page.page.pBitmap, CSAM_PAGE_BITMAP_SIZE);
379 AssertRCReturn(rc, rc);
380 }
381
382 return VINF_SUCCESS;
383}
384
385/**
386 * Execute state save operation.
387 *
388 * @returns VBox status code.
389 * @param pVM VM Handle.
390 * @param pSSM SSM operation handle.
391 */
392static DECLCALLBACK(int) csamr3Save(PVM pVM, PSSMHANDLE pSSM)
393{
394 CSAM csamInfo = pVM->csam.s;
395 int rc;
396
397 /*
398 * Count the number of page records in the tree (feeling lazy)
399 */
400 csamInfo.savedstate.cPageRecords = 0;
401 RTAvlPVDoWithAll(&pVM->csam.s.pPageTree, true, CountRecord, &csamInfo.savedstate.cPageRecords);
402
403 /*
404 * Save CSAM structure
405 */
406 pVM->csam.s.savedstate.pSSM = pSSM;
407 rc = SSMR3PutMem(pSSM, &csamInfo, sizeof(csamInfo));
408 AssertRCReturn(rc, rc);
409
410 /* Save pgdir bitmap */
411 rc = SSMR3PutMem(pSSM, csamInfo.pPDBitmapHC, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR));
412 AssertRCReturn(rc, rc);
413
414 for (unsigned i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
415 {
416 if(csamInfo.pPDBitmapHC[i])
417 {
418 /* Save the page bitmap. */
419 rc = SSMR3PutMem(pSSM, csamInfo.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
420 AssertRCReturn(rc, rc);
421 }
422 }
423
424 /*
425 * Save page records
426 */
427 rc = RTAvlPVDoWithAll(&pVM->csam.s.pPageTree, true, SavePageState, pVM);
428 AssertRCReturn(rc, rc);
429
430 /** @note we don't restore aDangerousInstr; it will be recreated automatically. */
431 return VINF_SUCCESS;
432}
433
434/**
435 * Execute state load operation.
436 *
437 * @returns VBox status code.
438 * @param pVM VM Handle.
439 * @param pSSM SSM operation handle.
440 * @param u32Version Data layout version.
441 */
442static DECLCALLBACK(int) csamr3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version)
443{
444 int rc;
445 CSAM csamInfo;
446
447 if (u32Version != CSAM_SSM_VERSION)
448 return VERR_SSM_UNSUPPORTED_DATA_UNIT_VERSION;
449
450 pVM->csam.s.savedstate.pSSM = pSSM;
451
452 /*
453 * Restore CSAM structure
454 */
455 rc = SSMR3GetMem(pSSM, &csamInfo, sizeof(csamInfo));
456 AssertRCReturn(rc, rc);
457
458 pVM->csam.s.fGatesChecked = csamInfo.fGatesChecked;
459 pVM->csam.s.fScanningStarted = csamInfo.fScanningStarted;
460
461 /* Restore dirty code page info. */
462 pVM->csam.s.cDirtyPages = csamInfo.cDirtyPages;
463 memcpy(pVM->csam.s.pvDirtyBasePage, csamInfo.pvDirtyBasePage, sizeof(pVM->csam.s.pvDirtyBasePage));
464 memcpy(pVM->csam.s.pvDirtyFaultPage, csamInfo.pvDirtyFaultPage, sizeof(pVM->csam.s.pvDirtyFaultPage));
465
466 /* Restore possible code page */
467 pVM->csam.s.cPossibleCodePages = csamInfo.cPossibleCodePages;
468 memcpy(pVM->csam.s.pvPossibleCodePage, csamInfo.pvPossibleCodePage, sizeof(pVM->csam.s.pvPossibleCodePage));
469
470 /* Restore pgdir bitmap (we'll change the pointers next). */
471 rc = SSMR3GetMem(pSSM, pVM->csam.s.pPDBitmapHC, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR));
472 AssertRCReturn(rc, rc);
473
474 /*
475 * Restore page bitmaps
476 */
477 for (unsigned i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
478 {
479 if(pVM->csam.s.pPDBitmapHC[i])
480 {
481 rc = MMHyperAlloc(pVM, CSAM_PAGE_BITMAP_SIZE, 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDBitmapHC[i]);
482 if (VBOX_FAILURE(rc))
483 {
484 Log(("MMR3HyperAlloc failed with %d\n", rc));
485 return rc;
486 }
487 /* Convert to GC pointer. */
488 pVM->csam.s.pPDGCBitmapHC[i] = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC[i]);
489 Assert(pVM->csam.s.pPDGCBitmapHC[i]);
490
491 /* Restore the bitmap. */
492 rc = SSMR3GetMem(pSSM, pVM->csam.s.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
493 AssertRCReturn(rc, rc);
494 }
495 else
496 {
497 Assert(!pVM->csam.s.pPDGCBitmapHC[i]);
498 pVM->csam.s.pPDGCBitmapHC[i] = 0;
499 }
500 }
501
502 /*
503 * Restore page records
504 */
505 for (uint32_t i=0;i<csamInfo.savedstate.cPageRecords + csamInfo.savedstate.cPatchPageRecords;i++)
506 {
507 CSAMPAGEREC page;
508 PCSAMPAGE pPage;
509
510 rc = SSMR3GetMem(pSSM, &page, sizeof(page));
511 AssertRCReturn(rc, rc);
512
513 /*
514 * Recreate the page record
515 */
516 pPage = csamCreatePageRecord(pVM, page.page.pPageGC, page.page.enmTag, page.page.fCode32, page.page.fMonitorInvalidation);
517 AssertReturn(pPage, VERR_NO_MEMORY);
518
519 pPage->GCPhys = page.page.GCPhys;
520 pPage->fFlags = page.page.fFlags;
521 pPage->u64Hash = page.page.u64Hash;
522
523 if (page.page.pBitmap)
524 {
525 rc = SSMR3GetMem(pSSM, pPage->pBitmap, CSAM_PAGE_BITMAP_SIZE);
526 AssertRCReturn(rc, rc);
527 }
528 else
529 {
530 MMR3HeapFree(pPage->pBitmap);
531 pPage->pBitmap = 0;
532 }
533 }
534
535 /** @note we don't restore aDangerousInstr; it will be recreated automatically. */
536 memset(&pVM->csam.s.aDangerousInstr, 0, sizeof(pVM->csam.s.aDangerousInstr));
537 pVM->csam.s.cDangerousInstr = 0;
538 pVM->csam.s.iDangerousInstr = 0;
539 return VINF_SUCCESS;
540}
541
542/**
543 * Convert guest context address to host context pointer
544 *
545 * @returns VBox status code.
546 * @param pVM The VM to operate on.
547 * @param pCacheRec Address conversion cache record
548 * @param pGCPtr Guest context pointer
549 *
550 * @returns Host context pointer or NULL in case of an error
551 *
552 */
553static R3PTRTYPE(void *) CSAMGCVirtToHCVirt(PVM pVM, PCSAMP2GLOOKUPREC pCacheRec, GCPTRTYPE(uint8_t *) pGCPtr)
554{
555 int rc;
556 R3PTRTYPE(void *) pHCPtr;
557
558 STAM_PROFILE_START(&pVM->csam.s.StatTimeAddrConv, a);
559
560 pHCPtr = PATMR3GCPtrToHCPtr(pVM, pGCPtr);
561 if (pHCPtr) return pHCPtr;
562
563 if (pCacheRec->pPageLocStartHC)
564 {
565 uint32_t offset = pGCPtr & PAGE_OFFSET_MASK;
566 if (pCacheRec->pGuestLoc == (pGCPtr & PAGE_BASE_GC_MASK))
567 {
568 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
569 return pCacheRec->pPageLocStartHC + offset;
570 }
571 }
572
573 rc = PGMPhysGCPtr2HCPtr(pVM, pGCPtr, &pHCPtr);
574 if (rc != VINF_SUCCESS)
575 {
576//// AssertMsgRC(rc, ("MMR3PhysGCVirt2HCVirtEx failed for %VGv\n", pGCPtr));
577 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
578 return NULL;
579 }
580////invalid? Assert(sizeof(R3PTRTYPE(uint8_t*)) == sizeof(uint32_t));
581
582 pCacheRec->pPageLocStartHC = (R3PTRTYPE(uint8_t*))((RTHCUINTPTR)pHCPtr & PAGE_BASE_HC_MASK);
583 pCacheRec->pGuestLoc = pGCPtr & PAGE_BASE_GC_MASK;
584 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
585 return pHCPtr;
586}
587
588/**
589 * Read callback for disassembly function; supports reading bytes that cross a page boundary
590 *
591 * @returns VBox status code.
592 * @param pSrc GC source pointer
593 * @param pDest HC destination pointer
594 * @param size Number of bytes to read
595 * @param dwUserdata Callback specific user data (pCpu)
596 *
597 */
598static DECLCALLBACK(int) CSAMR3ReadBytes(RTHCUINTPTR pSrc, uint8_t *pDest, unsigned size, void *pvUserdata)
599{
600 DISCPUSTATE *pCpu = (DISCPUSTATE *)pvUserdata;
601 PVM pVM = (PVM)pCpu->apvUserData[0];
602 RTHCUINTPTR pInstrHC = (RTHCUINTPTR)pCpu->apvUserData[1];
603 RTGCUINTPTR pInstrGC = (uintptr_t)pCpu->apvUserData[2];
604 int orgsize = size;
605
606 /* We are not interested in patched instructions, so read the original opcode bytes. */
607 /** @note single instruction patches (int3) are checked in CSAMR3AnalyseCallback */
608 for (int i=0;i<orgsize;i++)
609 {
610 int rc = PATMR3QueryOpcode(pVM, (RTGCPTR)pSrc, pDest);
611 if (VBOX_SUCCESS(rc))
612 {
613 pSrc++;
614 pDest++;
615 size--;
616 }
617 else
618 break;
619 }
620 if (size == 0)
621 return VINF_SUCCESS;
622
623 if (PAGE_ADDRESS(pInstrGC) != PAGE_ADDRESS(pSrc + size - 1) && !PATMIsPatchGCAddr(pVM, pSrc))
624 {
625 return PGMPhysReadGCPtr(pVM, pDest, pSrc, size);
626 }
627 else
628 {
629 Assert(pInstrHC);
630
631 /* pInstrHC is the base address; adjust according to the GC pointer. */
632 pInstrHC = pInstrHC + (pSrc - pInstrGC);
633
634 memcpy(pDest, (void *)pInstrHC, size);
635 }
636
637 return VINF_SUCCESS;
638}
639
640inline int CSAMR3DISInstr(PVM pVM, DISCPUSTATE *pCpu, RTGCPTR InstrGC, uint8_t *InstrHC, uint32_t *pOpsize, char *pszOutput)
641{
642 (pCpu)->pfnReadBytes = CSAMR3ReadBytes;
643 (pCpu)->apvUserData[0] = pVM;
644 (pCpu)->apvUserData[1] = InstrHC;
645 (pCpu)->apvUserData[2] = (void *)InstrGC; Assert(sizeof(InstrGC) <= sizeof(pCpu->apvUserData[0]));
646#ifdef DEBUG
647 return DISInstrEx(pCpu, InstrGC, 0, pOpsize, pszOutput, OPTYPE_ALL);
648#else
649 /* We are interested in everything except harmless stuff */
650 return DISInstrEx(pCpu, InstrGC, 0, pOpsize, pszOutput, ~(OPTYPE_INVALID | OPTYPE_HARMLESS | OPTYPE_RRM_MASK));
651#endif
652}
653
654/**
655 * Analyses the instructions following the cli for compliance with our heuristics for cli
656 *
657 * @returns VBox status code.
658 * @param pVM The VM to operate on.
659 * @param pCpu CPU disassembly state
660 * @param pInstrGC Guest context pointer to privileged instruction
661 * @param pCurInstrGC Guest context pointer to the current instruction
662 * @param pCacheRec GC to HC cache record
663 * @param pUserData User pointer (callback specific)
664 *
665 */
666static int CSAMR3AnalyseCallback(PVM pVM, DISCPUSTATE *pCpu, GCPTRTYPE(uint8_t *) pInstrGC, GCPTRTYPE(uint8_t *) pCurInstrGC,
667 PCSAMP2GLOOKUPREC pCacheRec, void *pUserData)
668{
669 PCSAMPAGE pPage = (PCSAMPAGE)pUserData;
670 int rc;
671
672 switch(pCpu->pCurInstr->opcode)
673 {
674 case OP_INT:
675 Assert(pCpu->param1.flags & USE_IMMEDIATE8);
676 if (pCpu->param1.parval == 3)
677 {
678 //two byte int 3
679 return VINF_SUCCESS;
680 }
681 break;
682
683 case OP_ILLUD2:
684 /* This appears to be some kind of kernel panic in Linux 2.4; no point to continue. */
685 case OP_RETN:
686 case OP_INT3:
687 case OP_INVALID:
688#if 1
689 /* removing breaks win2k guests? */
690 case OP_IRET:
691#endif
692 return VINF_SUCCESS;
693 }
694
695 // Check for exit points
696 switch (pCpu->pCurInstr->opcode)
697 {
698 /* It's not a good idea to patch pushf instructions:
699 * - increases the chance of conflicts (code jumping to the next instruction)
700 * - better to patch the cli
701 * - code that branches before the cli will likely hit an int 3
702 * - in general doesn't offer any benefits as we don't allow nested patch blocks (IF is always 1)
703 */
704 case OP_PUSHF:
705 case OP_POPF:
706 break;
707
708 case OP_CLI:
709 {
710 uint32_t cbInstr = 0;
711 uint32_t opsize = pCpu->opsize;
712
713 PATMR3AddHint(pVM, pCurInstrGC, (pPage->fCode32) ? PATMFL_CODE32 : 0);
714
715 /* Make sure the instructions that follow the cli have not been encountered before. */
716 while (true)
717 {
718 DISCPUSTATE cpu;
719 uint8_t *pCurInstrHC = 0;
720
721 if (cbInstr + opsize >= SIZEOF_NEARJUMP32)
722 break;
723
724 if (csamIsCodeScanned(pVM, pCurInstrGC + opsize, &pPage) == true)
725 {
726 /* We've scanned the next instruction(s) already. This means we've followed a branch that ended up there before -> dangerous!! */
727 PATMR3DetectConflict(pVM, pCurInstrGC, pCurInstrGC + opsize);
728 break;
729 }
730 pCurInstrGC += opsize;
731 cbInstr += opsize;
732
733 pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
734 if (pCurInstrHC == NULL)
735 {
736 Log(("CSAMGCVirtToHCVirt failed for %VGv\n", pCurInstrGC));
737 break;
738 }
739 Assert(VALID_PTR(pCurInstrHC));
740
741 cpu.mode = (pPage->fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
742 rc = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
743 Assert(VBOX_SUCCESS(rc));
744 if (VBOX_FAILURE(rc))
745 break;
746 }
747 break;
748 }
749
750 case OP_PUSH:
751 if (pCpu->pCurInstr->param1 != OP_PARM_REG_CS)
752 break;
753
754 /* no break */
755 case OP_STR:
756 case OP_LSL:
757 case OP_LAR:
758 case OP_SGDT:
759 case OP_SLDT:
760 case OP_SIDT:
761 case OP_SMSW:
762 case OP_VERW:
763 case OP_VERR:
764 case OP_CPUID:
765 case OP_IRET:
766#ifdef DEBUG
767 switch(pCpu->pCurInstr->opcode)
768 {
769 case OP_STR:
770 Log(("Privileged instruction at %VGv: str!!\n", pCurInstrGC));
771 break;
772 case OP_LSL:
773 Log(("Privileged instruction at %VGv: lsl!!\n", pCurInstrGC));
774 break;
775 case OP_LAR:
776 Log(("Privileged instruction at %VGv: lar!!\n", pCurInstrGC));
777 break;
778 case OP_SGDT:
779 Log(("Privileged instruction at %VGv: sgdt!!\n", pCurInstrGC));
780 break;
781 case OP_SLDT:
782 Log(("Privileged instruction at %VGv: sldt!!\n", pCurInstrGC));
783 break;
784 case OP_SIDT:
785 Log(("Privileged instruction at %VGv: sidt!!\n", pCurInstrGC));
786 break;
787 case OP_SMSW:
788 Log(("Privileged instruction at %VGv: smsw!!\n", pCurInstrGC));
789 break;
790 case OP_VERW:
791 Log(("Privileged instruction at %VGv: verw!!\n", pCurInstrGC));
792 break;
793 case OP_VERR:
794 Log(("Privileged instruction at %VGv: verr!!\n", pCurInstrGC));
795 break;
796 case OP_CPUID:
797 Log(("Privileged instruction at %VGv: cpuid!!\n", pCurInstrGC));
798 break;
799 case OP_PUSH:
800 Log(("Privileged instruction at %VGv: push cs!!\n", pCurInstrGC));
801 break;
802 case OP_IRET:
803 Log(("Privileged instruction at %VGv: iret!!\n", pCurInstrGC));
804 break;
805 }
806#endif
807
808 if (PATMR3HasBeenPatched(pVM, pCurInstrGC) == false)
809 {
810 rc = PATMR3InstallPatch(pVM, pCurInstrGC, (pPage->fCode32) ? PATMFL_CODE32 : 0);
811 if (VBOX_FAILURE(rc))
812 {
813 Log(("PATMR3InstallPatch failed with %d\n", rc));
814 return VWRN_CONTINUE_ANALYSIS;
815 }
816 }
817 if (pCpu->pCurInstr->opcode == OP_IRET)
818 return VINF_SUCCESS; /* Look no further in this branch. */
819
820 return VWRN_CONTINUE_ANALYSIS;
821
822 case OP_JMP:
823 case OP_CALL:
824 {
825 // return or jump/call through a jump table
826 if (OP_PARM_VTYPE(pCpu->pCurInstr->param1) != OP_PARM_J)
827 {
828#ifdef DEBUG
829 switch(pCpu->pCurInstr->opcode)
830 {
831 case OP_JMP:
832 Log(("Control Flow instruction at %VGv: jmp!!\n", pCurInstrGC));
833 break;
834 case OP_CALL:
835 Log(("Control Flow instruction at %VGv: call!!\n", pCurInstrGC));
836 break;
837 }
838#endif
839 return VWRN_CONTINUE_ANALYSIS;
840 }
841 return VWRN_CONTINUE_ANALYSIS;
842 }
843
844 }
845
846 return VWRN_CONTINUE_ANALYSIS;
847}
848
849#ifdef CSAM_ANALYSE_BEYOND_RET
850/**
851 * Wrapper for csamAnalyseCodeStream for call instructions.
852 *
853 * @returns VBox status code.
854 * @param pVM The VM to operate on.
855 * @param pInstrGC Guest context pointer to privileged instruction
856 * @param pCurInstrGC Guest context pointer to the current instruction
857 * @param fCode32 16 or 32 bits code
858 * @param pfnCSAMR3Analyse Callback for testing the disassembled instruction
859 * @param pUserData User pointer (callback specific)
860 *
861 */
862static int csamAnalyseCallCodeStream(PVM pVM, GCPTRTYPE(uint8_t *) pInstrGC, GCPTRTYPE(uint8_t *) pCurInstrGC, bool fCode32,
863 PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec)
864{
865 int rc;
866 CSAMCALLEXITREC CallExitRec;
867 PCSAMCALLEXITREC pOldCallRec;
868 PCSAMPAGE pPage = 0;
869 uint32_t i;
870
871 CallExitRec.cInstrAfterRet = 0;
872
873 pOldCallRec = pCacheRec->pCallExitRec;
874 pCacheRec->pCallExitRec = &CallExitRec;
875
876 rc = csamAnalyseCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
877
878 for (i=0;i<CallExitRec.cInstrAfterRet;i++)
879 {
880 PCSAMPAGE pPage = 0;
881
882 pCurInstrGC = CallExitRec.pInstrAfterRetGC[i];
883
884 /* Check if we've previously encountered the instruction after the ret. */
885 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
886 {
887 DISCPUSTATE cpu;
888 uint32_t opsize;
889 uint8_t *pCurInstrHC = 0;
890 int rc2;
891#ifdef DEBUG
892 char szOutput[256];
893#endif
894 if (pPage == NULL)
895 {
896 /* New address; let's take a look at it. */
897 pPage = csamCreatePageRecord(pVM, pCurInstrGC, CSAM_TAG_CSAM, fCode32);
898 if (pPage == NULL)
899 {
900 rc = VERR_NO_MEMORY;
901 goto done;
902 }
903 }
904
905 /**
906 * Some generic requirements for recognizing an adjacent function:
907 * - alignment fillers that consist of:
908 * - nop
909 * - lea genregX, [genregX (+ 0)]
910 * - push ebp after the filler (can extend this later); aligned at at least a 4 byte boundary
911 */
912 for (int j=0;j<16;j++)
913 {
914 pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
915 if (pCurInstrHC == NULL)
916 {
917 Log(("CSAMGCVirtToHCVirt failed for %VGv\n", pCurInstrGC));
918 goto done;
919 }
920 Assert(VALID_PTR(pCurInstrHC));
921
922 cpu.mode = (fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
923 STAM_PROFILE_START(&pVM->csam.s.StatTimeDisasm, a);
924#ifdef DEBUG
925 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, szOutput);
926 if (VBOX_SUCCESS(rc2)) Log(("CSAM Call Analysis: %s", szOutput));
927#else
928 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
929#endif
930 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeDisasm, a);
931 if (VBOX_FAILURE(rc2))
932 {
933 Log(("Disassembly failed at %VGv with %Vrc (probably page not present) -> return to caller\n", pCurInstrGC, rc2));
934 goto done;
935 }
936
937 STAM_COUNTER_ADD(&pVM->csam.s.StatNrBytesRead, opsize);
938
939 GCPTRTYPE(uint8_t *) addr = 0;
940 PCSAMPAGE pJmpPage = NULL;
941
942 if (PAGE_ADDRESS(pCurInstrGC) != PAGE_ADDRESS(pCurInstrGC + opsize - 1))
943 {
944 if (!PGMGstIsPagePresent(pVM, pCurInstrGC + opsize - 1))
945 {
946 /// @todo fault in the page
947 Log(("Page for current instruction %VGv is not present!!\n", pCurInstrGC));
948 goto done;
949 }
950 //all is fine, let's continue
951 csamR3CheckPageRecord(pVM, pCurInstrGC + opsize - 1);
952 }
953
954 switch (cpu.pCurInstr->opcode)
955 {
956 case OP_NOP:
957 case OP_INT3:
958 break; /* acceptable */
959
960 case OP_LEA:
961 /* Must be similar to:
962 *
963 * lea esi, [esi]
964 * lea esi, [esi+0]
965 * Any register is allowed as long as source and destination are identical.
966 */
967 if ( cpu.param1.flags != USE_REG_GEN32
968 || ( cpu.param2.flags != USE_REG_GEN32
969 && ( !(cpu.param2.flags & USE_REG_GEN32)
970 || !(cpu.param2.flags & (USE_DISPLACEMENT8|USE_DISPLACEMENT16|USE_DISPLACEMENT32))
971 || cpu.param2.parval != 0
972 )
973 )
974 || cpu.param1.base.reg_gen32 != cpu.param2.base.reg_gen32
975 )
976 {
977 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
978 goto next_function;
979 }
980 break;
981
982 case OP_PUSH:
983 {
984 if ( (pCurInstrGC & 0x3) != 0
985 || cpu.param1.flags != USE_REG_GEN32
986 || cpu.param1.base.reg_gen32 != USE_REG_EBP
987 )
988 {
989 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
990 goto next_function;
991 }
992
993 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
994 {
995 CSAMCALLEXITREC CallExitRec2;
996 CallExitRec2.cInstrAfterRet = 0;
997
998 pCacheRec->pCallExitRec = &CallExitRec2;
999
1000 /* Analyse the function. */
1001 Log(("Found new function at %VGv\n", pCurInstrGC));
1002 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunction);
1003 csamAnalyseCallCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
1004 }
1005 goto next_function;
1006 }
1007
1008 case OP_SUB:
1009 {
1010 if ( (pCurInstrGC & 0x3) != 0
1011 || cpu.param1.flags != USE_REG_GEN32
1012 || cpu.param1.base.reg_gen32 != USE_REG_ESP
1013 )
1014 {
1015 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
1016 goto next_function;
1017 }
1018
1019 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
1020 {
1021 CSAMCALLEXITREC CallExitRec2;
1022 CallExitRec2.cInstrAfterRet = 0;
1023
1024 pCacheRec->pCallExitRec = &CallExitRec2;
1025
1026 /* Analyse the function. */
1027 Log(("Found new function at %VGv\n", pCurInstrGC));
1028 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunction);
1029 csamAnalyseCallCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
1030 }
1031 goto next_function;
1032 }
1033
1034 default:
1035 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
1036 goto next_function;
1037 }
1038 /* Mark it as scanned. */
1039 csamMarkCode(pVM, pPage, pCurInstrGC, opsize, true);
1040 pCurInstrGC += opsize;
1041 } /* for at most 16 instructions */
1042next_function:
1043 ; /* MSVC complains otherwise */
1044 }
1045 }
1046done:
1047 pCacheRec->pCallExitRec = pOldCallRec;
1048 return rc;
1049}
1050#else
1051#define csamAnalyseCallCodeStream csamAnalyseCodeStream
1052#endif
1053
1054/**
1055 * Disassembles the code stream until the callback function detects a failure or decides everything is acceptable
1056 *
1057 * @returns VBox status code.
1058 * @param pVM The VM to operate on.
1059 * @param pInstrGC Guest context pointer to privileged instruction
1060 * @param pCurInstrGC Guest context pointer to the current instruction
1061 * @param fCode32 16 or 32 bits code
1062 * @param pfnCSAMR3Analyse Callback for testing the disassembled instruction
1063 * @param pUserData User pointer (callback specific)
1064 *
1065 */
1066static int csamAnalyseCodeStream(PVM pVM, GCPTRTYPE(uint8_t *) pInstrGC, GCPTRTYPE(uint8_t *) pCurInstrGC, bool fCode32,
1067 PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec)
1068{
1069 DISCPUSTATE cpu;
1070 PCSAMPAGE pPage = (PCSAMPAGE)pUserData;
1071 int rc = VWRN_CONTINUE_ANALYSIS;
1072 uint32_t opsize;
1073 R3PTRTYPE(uint8_t *) pCurInstrHC = 0;
1074 int rc2;
1075
1076#ifdef DEBUG
1077 char szOutput[256];
1078#endif
1079
1080 LogFlow(("csamAnalyseCodeStream: code at %VGv depth=%d\n", pCurInstrGC, pCacheRec->depth));
1081
1082 pVM->csam.s.fScanningStarted = true;
1083
1084 pCacheRec->depth++;
1085 /*
1086 * Limit the call depth. (rather arbitrary upper limit; too low and we won't detect certain
1087 * cpuid instructions in Linux kernels; too high and we waste too much time scanning code)
1088 * (512 is necessary to detect cpuid instructions in Red Hat EL4; see defect 1355)
1089 * @note we are using a lot of stack here. couple of 100k when we go to the full depth (!)
1090 */
1091 if (pCacheRec->depth > 512)
1092 {
1093 LogFlow(("CSAM: maximum calldepth reached for %VGv\n", pCurInstrGC));
1094 pCacheRec->depth--;
1095 return VINF_SUCCESS; //let's not go on forever
1096 }
1097
1098 Assert(!PATMIsPatchGCAddr(pVM, pCurInstrGC));
1099 csamR3CheckPageRecord(pVM, pCurInstrGC);
1100
1101 while(rc == VWRN_CONTINUE_ANALYSIS)
1102 {
1103 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
1104 {
1105 if (pPage == NULL)
1106 {
1107 /* New address; let's take a look at it. */
1108 pPage = csamCreatePageRecord(pVM, pCurInstrGC, CSAM_TAG_CSAM, fCode32);
1109 if (pPage == NULL)
1110 {
1111 rc = VERR_NO_MEMORY;
1112 goto done;
1113 }
1114 }
1115 }
1116 else
1117 {
1118 LogFlow(("Code at %VGv has been scanned before\n", pCurInstrGC));
1119 rc = VINF_SUCCESS;
1120 goto done;
1121 }
1122
1123 pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
1124 if (pCurInstrHC == NULL)
1125 {
1126 Log(("CSAMGCVirtToHCVirt failed for %VGv\n", pCurInstrGC));
1127 rc = VERR_PATCHING_REFUSED;
1128 goto done;
1129 }
1130 Assert(VALID_PTR(pCurInstrHC));
1131
1132 cpu.mode = (fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
1133 STAM_PROFILE_START(&pVM->csam.s.StatTimeDisasm, a);
1134#ifdef DEBUG
1135 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, szOutput);
1136 if (VBOX_SUCCESS(rc2)) Log(("CSAM Analysis: %s", szOutput));
1137#else
1138 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
1139#endif
1140 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeDisasm, a);
1141 if (VBOX_FAILURE(rc2))
1142 {
1143 Log(("Disassembly failed at %VGv with %Vrc (probably page not present) -> return to caller\n", pCurInstrGC, rc2));
1144 rc = VINF_SUCCESS;
1145 goto done;
1146 }
1147
1148 STAM_COUNTER_ADD(&pVM->csam.s.StatNrBytesRead, opsize);
1149
1150 csamMarkCode(pVM, pPage, pCurInstrGC, opsize, true);
1151
1152 GCPTRTYPE(uint8_t *) addr = 0;
1153 PCSAMPAGE pJmpPage = NULL;
1154
1155 if (PAGE_ADDRESS(pCurInstrGC) != PAGE_ADDRESS(pCurInstrGC + opsize - 1))
1156 {
1157 if (!PGMGstIsPagePresent(pVM, pCurInstrGC + opsize - 1))
1158 {
1159 /// @todo fault in the page
1160 Log(("Page for current instruction %VGv is not present!!\n", pCurInstrGC));
1161 rc = VWRN_CONTINUE_ANALYSIS;
1162 goto next_please;
1163 }
1164 //all is fine, let's continue
1165 csamR3CheckPageRecord(pVM, pCurInstrGC + opsize - 1);
1166 }
1167 /*
1168 * If it's harmless, then don't bother checking it (the disasm tables had better be accurate!)
1169 */
1170 if ((cpu.pCurInstr->optype & ~OPTYPE_RRM_MASK) == OPTYPE_HARMLESS)
1171 {
1172 AssertMsg(pfnCSAMR3Analyse(pVM, &cpu, pInstrGC, pCurInstrGC, pCacheRec, (void *)pPage) == VWRN_CONTINUE_ANALYSIS, ("Instruction incorrectly marked harmless?!?!?\n"));
1173 rc = VWRN_CONTINUE_ANALYSIS;
1174 goto next_please;
1175 }
1176
1177#ifdef CSAM_ANALYSE_BEYOND_RET
1178 /* Remember the address of the instruction following the ret in case the parent instruction was a call. */
1179 if ( pCacheRec->pCallExitRec
1180 && cpu.pCurInstr->opcode == OP_RETN
1181 && pCacheRec->pCallExitRec->cInstrAfterRet < CSAM_MAX_CALLEXIT_RET)
1182 {
1183 pCacheRec->pCallExitRec->pInstrAfterRetGC[pCacheRec->pCallExitRec->cInstrAfterRet] = pCurInstrGC + opsize;
1184 pCacheRec->pCallExitRec->cInstrAfterRet++;
1185 }
1186#endif
1187
1188 rc = pfnCSAMR3Analyse(pVM, &cpu, pInstrGC, pCurInstrGC, pCacheRec, (void *)pPage);
1189 if (rc == VINF_SUCCESS)
1190 goto done;
1191
1192 // For our first attempt, we'll handle only simple relative jumps and calls (immediate offset coded in instruction)
1193 if ( ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1194 || (cpu.pCurInstr->opcode == OP_CALL && cpu.param1.flags == USE_DISPLACEMENT32)) /* simple indirect call (call dword ptr [address]) */
1195 {
1196 /* We need to parse 'call dword ptr [address]' type of calls to catch cpuid instructions in some recent Linux distributions (e.g. OpenSuse 10.3) */
1197 if ( cpu.pCurInstr->opcode == OP_CALL
1198 && cpu.param1.flags == USE_DISPLACEMENT32)
1199 {
1200 addr = 0;
1201 PGMPhysReadGCPtr(pVM, &addr, cpu.param1.disp32, sizeof(addr));
1202 }
1203 else
1204 addr = CSAMResolveBranch(&cpu, pCurInstrGC);
1205
1206 if (addr == 0)
1207 {
1208 Log(("We don't support far jumps here!! (%08X)\n", cpu.param1.flags));
1209 rc = VINF_SUCCESS;
1210 break;
1211 }
1212 Assert(!PATMIsPatchGCAddr(pVM, addr));
1213
1214 /* If the target address lies in a patch generated jump, then special action needs to be taken. */
1215 PATMR3DetectConflict(pVM, pCurInstrGC, addr);
1216
1217 /* Same page? */
1218 if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pCurInstrGC ))
1219 {
1220 if (!PGMGstIsPagePresent(pVM, addr))
1221 {
1222 Log(("Page for current instruction %VGv is not present!!\n", addr));
1223 rc = VWRN_CONTINUE_ANALYSIS;
1224 goto next_please;
1225 }
1226
1227 /* All is fine, let's continue. */
1228 csamR3CheckPageRecord(pVM, addr);
1229 }
1230
1231 pJmpPage = NULL;
1232 if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1233 {
1234 if (pJmpPage == NULL)
1235 {
1236 /* New branch target; let's take a look at it. */
1237 pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1238 if (pJmpPage == NULL)
1239 {
1240 rc = VERR_NO_MEMORY;
1241 goto done;
1242 }
1243 Assert(pPage);
1244 }
1245 if (cpu.pCurInstr->opcode == OP_CALL)
1246 rc = csamAnalyseCallCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1247 else
1248 rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1249
1250 if (rc != VINF_SUCCESS) {
1251 goto done;
1252 }
1253 }
1254 if (cpu.pCurInstr->opcode == OP_JMP)
1255 {//unconditional jump; return to caller
1256 rc = VINF_SUCCESS;
1257 goto done;
1258 }
1259
1260 rc = VWRN_CONTINUE_ANALYSIS;
1261 } //if ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1262#ifdef CSAM_SCAN_JUMP_TABLE
1263 else
1264 if ( cpu.pCurInstr->opcode == OP_JMP
1265 && (cpu.param1.flags & (USE_DISPLACEMENT32|USE_INDEX|USE_SCALE)) == (USE_DISPLACEMENT32|USE_INDEX|USE_SCALE)
1266 )
1267 {
1268 RTGCPTR pJumpTableGC = (RTGCPTR)cpu.param1.disp32;
1269 uint8_t *pJumpTableHC;
1270 int rc2;
1271
1272 Log(("Jump through jump table\n"));
1273
1274 rc2 = PGMPhysGCPtr2HCPtr(pVM, pJumpTableGC, (PRTHCPTR)&pJumpTableHC);
1275 if (rc2 == VINF_SUCCESS)
1276 {
1277 for (uint32_t i=0;i<2;i++)
1278 {
1279 uint64_t fFlags;
1280
1281 addr = pJumpTableGC + cpu.param1.scale * i;
1282 /* Same page? */
1283 if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pJumpTableGC))
1284 break;
1285
1286 addr = *(RTGCPTR *)(pJumpTableHC + cpu.param1.scale * i);
1287
1288 rc2 = PGMGstGetPage(pVM, addr, &fFlags, NULL);
1289 if ( rc2 != VINF_SUCCESS
1290 || (fFlags & X86_PTE_US)
1291 || !(fFlags & X86_PTE_P)
1292 )
1293 break;
1294
1295 Log(("Jump to %VGv\n", addr));
1296
1297 pJmpPage = NULL;
1298 if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1299 {
1300 if (pJmpPage == NULL)
1301 {
1302 /* New branch target; let's take a look at it. */
1303 pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1304 if (pJmpPage == NULL)
1305 {
1306 rc = VERR_NO_MEMORY;
1307 goto done;
1308 }
1309 Assert(pPage);
1310 }
1311 rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1312 if (rc != VINF_SUCCESS) {
1313 goto done;
1314 }
1315 }
1316 }
1317 }
1318 }
1319#endif
1320 if (rc != VWRN_CONTINUE_ANALYSIS) {
1321 break; //done!
1322 }
1323next_please:
1324 if (cpu.pCurInstr->opcode == OP_JMP)
1325 {
1326 rc = VINF_SUCCESS;
1327 goto done;
1328 }
1329 pCurInstrGC += opsize;
1330 }
1331done:
1332 pCacheRec->depth--;
1333 return rc;
1334}
1335
1336
1337/**
1338 * Calculates the 64 bits hash value for the current page
1339 *
1340 * @returns hash value
1341 * @param pVM The VM to operate on.
1342 * @param pInstr Page address
1343 */
1344uint64_t csamR3CalcPageHash(PVM pVM, RTGCPTR pInstr)
1345{
1346 uint64_t hash = 0;
1347 uint32_t val[5];
1348 int rc;
1349
1350 Assert((pInstr & PAGE_OFFSET_MASK) == 0);
1351
1352 rc = PGMPhysReadGCPtr(pVM, &val[0], pInstr, sizeof(val[0]));
1353 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1354 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1355 {
1356 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1357 return ~0ULL;
1358 }
1359
1360 rc = PGMPhysReadGCPtr(pVM, &val[1], pInstr+1024, sizeof(val[0]));
1361 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1362 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1363 {
1364 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1365 return ~0ULL;
1366 }
1367
1368 rc = PGMPhysReadGCPtr(pVM, &val[2], pInstr+2048, sizeof(val[0]));
1369 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1370 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1371 {
1372 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1373 return ~0ULL;
1374 }
1375
1376 rc = PGMPhysReadGCPtr(pVM, &val[3], pInstr+3072, sizeof(val[0]));
1377 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1378 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1379 {
1380 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1381 return ~0ULL;
1382 }
1383
1384 rc = PGMPhysReadGCPtr(pVM, &val[4], pInstr+4092, sizeof(val[0]));
1385 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1386 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1387 {
1388 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1389 return ~0ULL;
1390 }
1391
1392 // don't want to get division by zero traps
1393 val[2] |= 1;
1394 val[4] |= 1;
1395
1396 hash = (uint64_t)val[0] * (uint64_t)val[1] / (uint64_t)val[2] + (val[3]%val[4]);
1397 return (hash == ~0ULL) ? hash - 1 : hash;
1398}
1399
1400
1401/**
1402 * Notify CSAM of a page flush
1403 *
1404 * @returns VBox status code
1405 * @param pVM The VM to operate on.
1406 * @param addr GC address of the page to flush
1407 * @param fRemovePage Page removal flag
1408 */
1409static int csamFlushPage(PVM pVM, RTGCPTR addr, bool fRemovePage)
1410{
1411 PCSAMPAGEREC pPageRec;
1412 int rc;
1413 RTGCPHYS GCPhys = 0;
1414 uint64_t fFlags = 0;
1415
1416 if (!CSAMIsEnabled(pVM))
1417 return VINF_SUCCESS;
1418
1419 STAM_PROFILE_START(&pVM->csam.s.StatTimeFlushPage, a);
1420
1421 addr = addr & PAGE_BASE_GC_MASK;
1422
1423 /*
1424 * Note: searching for the page in our tree first is more expensive (skipped flushes are two orders of magnitude more common)
1425 */
1426 if (pVM->csam.s.pPageTree == NULL)
1427 {
1428 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1429 return VWRN_CSAM_PAGE_NOT_FOUND;
1430 }
1431
1432 rc = PGMGstGetPage(pVM, addr, &fFlags, &GCPhys);
1433 /* Returned at a very early stage (no paging yet presumably). */
1434 if (rc == VERR_NOT_SUPPORTED)
1435 {
1436 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1437 return rc;
1438 }
1439
1440 if (VBOX_SUCCESS(rc))
1441 {
1442 if ( (fFlags & X86_PTE_US)
1443 || rc == VERR_PGM_PHYS_PAGE_RESERVED
1444 )
1445 {
1446 /* User page -> not relevant for us. */
1447 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1448 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1449 return VINF_SUCCESS;
1450 }
1451 }
1452 else
1453 if (rc != VERR_PAGE_NOT_PRESENT && rc != VERR_PAGE_TABLE_NOT_PRESENT)
1454 AssertMsgFailed(("PGMR3GetPage %VGv failed with %Vrc\n", addr, rc));
1455
1456 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1457 if (pPageRec)
1458 {
1459 if ( GCPhys == pPageRec->page.GCPhys
1460 && (fFlags & X86_PTE_P))
1461 {
1462 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1463 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1464 return VINF_SUCCESS;
1465 }
1466
1467 Log(("CSAMR3FlushPage: page %VGv has changed -> FLUSH (rc=%Vrc) (Phys: %VGp vs %VGp)\n", addr, rc, GCPhys, pPageRec->page.GCPhys));
1468
1469 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushes, 1);
1470
1471 if (fRemovePage)
1472 csamRemovePageRecord(pVM, addr);
1473 else
1474 {
1475 CSAMMarkPage(pVM, addr, false);
1476 pPageRec->page.GCPhys = 0;
1477 pPageRec->page.fFlags = 0;
1478 rc = PGMGstGetPage(pVM, addr, &pPageRec->page.fFlags, &pPageRec->page.GCPhys);
1479 if (rc == VINF_SUCCESS)
1480 pPageRec->page.u64Hash = csamR3CalcPageHash(pVM, addr);
1481
1482 if (pPageRec->page.pBitmap == NULL)
1483 {
1484 pPageRec->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, CSAM_PAGE_BITMAP_SIZE);
1485 Assert(pPageRec->page.pBitmap);
1486 if (pPageRec->page.pBitmap == NULL)
1487 return VERR_NO_MEMORY;
1488 }
1489 else
1490 memset(pPageRec->page.pBitmap, 0, CSAM_PAGE_BITMAP_SIZE);
1491 }
1492
1493
1494 /*
1495 * Inform patch manager about the flush; no need to repeat the above check twice.
1496 */
1497 PATMR3FlushPage(pVM, addr);
1498
1499 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1500 return VINF_SUCCESS;
1501 }
1502 else
1503 {
1504 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1505 return VWRN_CSAM_PAGE_NOT_FOUND;
1506 }
1507}
1508
1509/**
1510 * Notify CSAM of a page flush
1511 *
1512 * @returns VBox status code
1513 * @param pVM The VM to operate on.
1514 * @param addr GC address of the page to flush
1515 */
1516CSAMR3DECL(int) CSAMR3FlushPage(PVM pVM, RTGCPTR addr)
1517{
1518 return csamFlushPage(pVM, addr, true /* remove page record */);
1519}
1520
1521/**
1522 * Remove a CSAM monitored page. Use with care!
1523 *
1524 * @returns VBox status code
1525 * @param pVM The VM to operate on.
1526 * @param addr GC address of the page to flush
1527 */
1528CSAMR3DECL(int) CSAMR3RemovePage(PVM pVM, RTGCPTR addr)
1529{
1530 PCSAMPAGEREC pPageRec;
1531 int rc;
1532
1533 addr = addr & PAGE_BASE_GC_MASK;
1534
1535 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1536 if (pPageRec)
1537 {
1538 rc = csamRemovePageRecord(pVM, addr);
1539 if (VBOX_SUCCESS(rc))
1540 PATMR3FlushPage(pVM, addr);
1541 return VINF_SUCCESS;
1542 }
1543 return VWRN_CSAM_PAGE_NOT_FOUND;
1544}
1545
1546/**
1547 * Check a page record in case a page has been changed
1548 *
1549 * @returns VBox status code. (trap handled or not)
1550 * @param pVM The VM to operate on.
1551 * @param pInstrGC GC instruction pointer
1552 */
1553int csamR3CheckPageRecord(PVM pVM, RTGCPTR pInstrGC)
1554{
1555 PCSAMPAGEREC pPageRec;
1556 uint64_t u64hash;
1557
1558 pInstrGC = pInstrGC & PAGE_BASE_GC_MASK;
1559
1560 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstrGC);
1561 if (pPageRec)
1562 {
1563 u64hash = csamR3CalcPageHash(pVM, pInstrGC);
1564 if (u64hash != pPageRec->page.u64Hash)
1565 csamFlushPage(pVM, pInstrGC, false /* don't remove page record */);
1566 }
1567 else
1568 return VWRN_CSAM_PAGE_NOT_FOUND;
1569
1570 return VINF_SUCCESS;
1571}
1572
1573/**
1574 * Returns monitor description based on CSAM tag
1575 *
1576 * @return description string
1577 * @param enmTag Owner tag
1578 */
1579const char *csamGetMonitorDescription(CSAMTAG enmTag)
1580{
1581 if (enmTag == CSAM_TAG_PATM)
1582 return "CSAM-PATM self-modifying code monitor handler";
1583 else
1584 if (enmTag == CSAM_TAG_REM)
1585 return "CSAM-REM self-modifying code monitor handler";
1586 Assert(enmTag == CSAM_TAG_CSAM);
1587 return "CSAM self-modifying code monitor handler";
1588}
1589
1590/**
1591 * Adds page record to our lookup tree
1592 *
1593 * @returns CSAMPAGE ptr or NULL if failure
1594 * @param pVM The VM to operate on.
1595 * @param GCPtr Page address
1596 * @param enmTag Owner tag
1597 * @param fCode32 16 or 32 bits code
1598 * @param fMonitorInvalidation Monitor page invalidation flag
1599 */
1600static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTGCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation)
1601{
1602 PCSAMPAGEREC pPage;
1603 int rc;
1604 bool ret;
1605
1606 Log(("New page record for %VGv\n", GCPtr & PAGE_BASE_GC_MASK));
1607
1608 pPage = (PCSAMPAGEREC)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, sizeof(CSAMPAGEREC));
1609 if (pPage == NULL)
1610 {
1611 AssertMsgFailed(("csamCreatePageRecord: Out of memory!!!!\n"));
1612 return NULL;
1613 }
1614 /* Round down to page boundary. */
1615 GCPtr = (GCPtr & PAGE_BASE_GC_MASK);
1616 pPage->Core.Key = (AVLPVKEY)GCPtr;
1617 pPage->page.pPageGC = GCPtr;
1618 pPage->page.fCode32 = fCode32;
1619 pPage->page.fMonitorInvalidation = fMonitorInvalidation;
1620 pPage->page.enmTag = enmTag;
1621 pPage->page.fMonitorActive = false;
1622 pPage->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, PAGE_SIZE/sizeof(uint8_t));
1623 rc = PGMGstGetPage(pVM, GCPtr, &pPage->page.fFlags, &pPage->page.GCPhys);
1624 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1625
1626 pPage->page.u64Hash = csamR3CalcPageHash(pVM, GCPtr);
1627 ret = RTAvlPVInsert(&pVM->csam.s.pPageTree, &pPage->Core);
1628 Assert(ret);
1629
1630#ifdef CSAM_MONITOR_CODE_PAGES
1631 AssertRelease(!fInCSAMCodePageInvalidate);
1632
1633 switch (enmTag)
1634 {
1635 case CSAM_TAG_PATM:
1636 case CSAM_TAG_REM:
1637#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1638 case CSAM_TAG_CSAM:
1639#endif
1640 {
1641 int rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GCPtr, GCPtr + (PAGE_SIZE - 1) /* inclusive! */,
1642 (fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1643 csamGetMonitorDescription(enmTag));
1644 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VGv failed with %Vrc\n", GCPtr, rc));
1645 if (VBOX_FAILURE(rc))
1646 Log(("PGMR3HandlerVirtualRegisterEx for %VGv failed with %Vrc\n", GCPtr, rc));
1647
1648 /* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1649
1650 /* Prefetch it in case it's not there yet. */
1651 rc = PGMPrefetchPage(pVM, GCPtr);
1652 AssertRC(rc);
1653
1654 rc = PGMShwModifyPage(pVM, GCPtr, 1, 0, ~(uint64_t)X86_PTE_RW);
1655 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1656
1657 pPage->page.fMonitorActive = true;
1658 STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1659 break;
1660 }
1661 default:
1662 break; /* to shut up GCC */
1663 }
1664
1665 Log(("csamCreatePageRecord %VGv HCPhys=%VGp\n", GCPtr, pPage->page.GCPhys));
1666
1667#ifdef VBOX_WITH_STATISTICS
1668 switch (enmTag)
1669 {
1670 case CSAM_TAG_CSAM:
1671 STAM_COUNTER_INC(&pVM->csam.s.StatPageCSAM);
1672 break;
1673 case CSAM_TAG_PATM:
1674 STAM_COUNTER_INC(&pVM->csam.s.StatPagePATM);
1675 break;
1676 case CSAM_TAG_REM:
1677 STAM_COUNTER_INC(&pVM->csam.s.StatPageREM);
1678 break;
1679 default:
1680 break; /* to shut up GCC */
1681 }
1682#endif
1683
1684#endif
1685
1686 STAM_COUNTER_INC(&pVM->csam.s.StatNrPages);
1687 if (fMonitorInvalidation)
1688 STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1689
1690 return &pPage->page;
1691}
1692
1693/**
1694 * Monitors a code page (if not already monitored)
1695 *
1696 * @returns VBox status code
1697 * @param pVM The VM to operate on.
1698 * @param pPageAddrGC The page to monitor
1699 * @param enmTag Monitor tag
1700 */
1701CSAMR3DECL(int) CSAMR3MonitorPage(PVM pVM, RTGCPTR pPageAddrGC, CSAMTAG enmTag)
1702{
1703 PCSAMPAGEREC pPageRec = NULL;
1704 int rc;
1705 bool fMonitorInvalidation;
1706
1707 /* Dirty pages must be handled before calling this function!. */
1708 Assert(!pVM->csam.s.cDirtyPages);
1709
1710 if (pVM->csam.s.fScanningStarted == false)
1711 return VINF_SUCCESS; /* too early */
1712
1713 pPageAddrGC &= PAGE_BASE_GC_MASK;
1714
1715 Log(("CSAMR3MonitorPage %VGv %d\n", pPageAddrGC, enmTag));
1716
1717 /** @todo implicit assumption */
1718 fMonitorInvalidation = (enmTag == CSAM_TAG_PATM);
1719
1720 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1721 if (pPageRec == NULL)
1722 {
1723 uint64_t fFlags;
1724
1725 rc = PGMGstGetPage(pVM, pPageAddrGC, &fFlags, NULL);
1726 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1727 if ( rc == VINF_SUCCESS
1728 && (fFlags & X86_PTE_US))
1729 {
1730 /* We don't care about user pages. */
1731 STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
1732 return VINF_SUCCESS;
1733 }
1734
1735 csamCreatePageRecord(pVM, pPageAddrGC, enmTag, true /* 32 bits code */, fMonitorInvalidation);
1736
1737 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1738 Assert(pPageRec);
1739 }
1740 /** @todo reference count */
1741
1742#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1743 Assert(pPageRec->page.fMonitorActive);
1744#endif
1745
1746#ifdef CSAM_MONITOR_CODE_PAGES
1747 if (!pPageRec->page.fMonitorActive)
1748 {
1749 Log(("CSAMR3MonitorPage: activate monitoring for %VGv\n", pPageAddrGC));
1750
1751 rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, pPageAddrGC, pPageAddrGC + (PAGE_SIZE - 1) /* inclusive! */,
1752 (fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1753 csamGetMonitorDescription(enmTag));
1754 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VGv failed with %Vrc\n", pPageAddrGC, rc));
1755 if (VBOX_FAILURE(rc))
1756 Log(("PGMR3HandlerVirtualRegisterEx for %VGv failed with %Vrc\n", pPageAddrGC, rc));
1757
1758 /* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1759
1760 /* Prefetch it in case it's not there yet. */
1761 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1762 AssertRC(rc);
1763
1764 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1765 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1766
1767 STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1768
1769 pPageRec->page.fMonitorActive = true;
1770 pPageRec->page.fMonitorInvalidation = fMonitorInvalidation;
1771 }
1772 else
1773 if ( !pPageRec->page.fMonitorInvalidation
1774 && fMonitorInvalidation)
1775 {
1776 Assert(pPageRec->page.fMonitorActive);
1777 PGMHandlerVirtualChangeInvalidateCallback(pVM, pPageRec->page.pPageGC, CSAMCodePageInvalidate);
1778 pPageRec->page.fMonitorInvalidation = true;
1779 STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1780
1781 /* Prefetch it in case it's not there yet. */
1782 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1783 AssertRC(rc);
1784
1785 /* Make sure it's readonly. Page invalidation may have modified the attributes. */
1786 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1787 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1788 }
1789
1790#if 0 /* def VBOX_STRICT -> very annoying) */
1791 if (pPageRec->page.fMonitorActive)
1792 {
1793 uint64_t fPageShw;
1794 RTHCPHYS GCPhys;
1795 rc = PGMShwGetPage(pVM, pPageAddrGC, &fPageShw, &GCPhys);
1796// AssertMsg( (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1797// || !(fPageShw & X86_PTE_RW)
1798// || (pPageRec->page.GCPhys == 0), ("Shadow page flags for %VGv (%VHp) aren't readonly (%VX64)!!\n", pPageAddrGC, GCPhys, fPageShw));
1799 }
1800#endif
1801
1802 if (pPageRec->page.GCPhys == 0)
1803 {
1804 /* Prefetch it in case it's not there yet. */
1805 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1806 AssertRC(rc);
1807 /* The page was changed behind our back. It won't be made read-only until the next SyncCR3, so force it here. */
1808 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1809 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1810 }
1811#endif /* CSAM_MONITOR_CODE_PAGES */
1812 return VINF_SUCCESS;
1813}
1814
1815/**
1816 * Removes a page record from our lookup tree
1817 *
1818 * @returns VBox status code
1819 * @param pVM The VM to operate on.
1820 * @param GCPtr Page address
1821 */
1822static int csamRemovePageRecord(PVM pVM, RTGCPTR GCPtr)
1823{
1824 PCSAMPAGEREC pPageRec;
1825
1826 Log(("csamRemovePageRecord %VGv\n", GCPtr));
1827 pPageRec = (PCSAMPAGEREC)RTAvlPVRemove(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
1828
1829 if (pPageRec)
1830 {
1831 STAM_COUNTER_INC(&pVM->csam.s.StatNrRemovedPages);
1832
1833#ifdef CSAM_MONITOR_CODE_PAGES
1834 if (pPageRec->page.fMonitorActive)
1835 {
1836 /* @todo -> this is expensive (cr3 reload)!!!
1837 * if this happens often, then reuse it instead!!!
1838 */
1839 Assert(!fInCSAMCodePageInvalidate);
1840 STAM_COUNTER_DEC(&pVM->csam.s.StatPageMonitor);
1841 PGMHandlerVirtualDeregister(pVM, GCPtr);
1842 }
1843 if (pPageRec->page.enmTag == CSAM_TAG_PATM)
1844 {
1845 /* Make sure the recompiler flushes its cache as this page is no longer monitored. */
1846 STAM_COUNTER_INC(&pVM->csam.s.StatPageRemoveREMFlush);
1847 CPUMSetChangedFlags(pVM, CPUM_CHANGED_GLOBAL_TLB_FLUSH);
1848 }
1849#endif
1850
1851#ifdef VBOX_WITH_STATISTICS
1852 switch (pPageRec->page.enmTag)
1853 {
1854 case CSAM_TAG_CSAM:
1855 STAM_COUNTER_DEC(&pVM->csam.s.StatPageCSAM);
1856 break;
1857 case CSAM_TAG_PATM:
1858 STAM_COUNTER_DEC(&pVM->csam.s.StatPagePATM);
1859 break;
1860 case CSAM_TAG_REM:
1861 STAM_COUNTER_DEC(&pVM->csam.s.StatPageREM);
1862 break;
1863 default:
1864 break; /* to shut up GCC */
1865 }
1866#endif
1867
1868 if (pPageRec->page.pBitmap) MMR3HeapFree(pPageRec->page.pBitmap);
1869 MMR3HeapFree(pPageRec);
1870 }
1871 else
1872 AssertFailed();
1873
1874 return VINF_SUCCESS;
1875}
1876
1877/**
1878 * Callback for delayed writes from non-EMT threads
1879 *
1880 * @param pVM VM Handle.
1881 * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1882 * @param cbBuf How much it's reading/writing.
1883 */
1884static DECLCALLBACK(void) CSAMDelayedWriteHandler(PVM pVM, RTGCPTR GCPtr, size_t cbBuf)
1885{
1886 int rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1887 AssertRC(rc);
1888}
1889
1890/**
1891 * #PF Handler callback for virtual access handler ranges.
1892 *
1893 * Important to realize that a physical page in a range can have aliases, and
1894 * for ALL and WRITE handlers these will also trigger.
1895 *
1896 * @returns VINF_SUCCESS if the handler have carried out the operation.
1897 * @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation.
1898 * @param pVM VM Handle.
1899 * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1900 * @param pvPtr The HC mapping of that address.
1901 * @param pvBuf What the guest is reading/writing.
1902 * @param cbBuf How much it's reading/writing.
1903 * @param enmAccessType The access type.
1904 * @param pvUser User argument.
1905 */
1906static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser)
1907{
1908 int rc;
1909
1910 Assert(enmAccessType == PGMACCESSTYPE_WRITE);
1911 Log(("CSAMCodePageWriteHandler: write to %VGv size=%d\n", GCPtr, cbBuf));
1912
1913 if (VM_IS_EMT(pVM))
1914 {
1915 rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1916 }
1917 else
1918 {
1919 /* Queue the write instead otherwise we'll get concurrency issues. */
1920 /** @note in theory not correct to let it write the data first before disabling a patch!
1921 * (if it writes the same data as the patch jump and we replace it with obsolete opcodes)
1922 */
1923 Log(("CSAMCodePageWriteHandler: delayed write!\n"));
1924 rc = VMR3ReqCallEx(pVM, NULL, 0, VMREQFLAGS_NO_WAIT | VMREQFLAGS_VOID,
1925 (PFNRT)CSAMDelayedWriteHandler, 3, pVM, GCPtr, cbBuf);
1926 }
1927 AssertRC(rc);
1928
1929 return VINF_PGM_HANDLER_DO_DEFAULT;
1930}
1931
1932/**
1933 * #PF Handler callback for invalidation of virtual access handler ranges.
1934 *
1935 * @param pVM VM Handle.
1936 * @param GCPtr The virtual address the guest has changed.
1937 */
1938static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr)
1939{
1940 fInCSAMCodePageInvalidate = true;
1941 LogFlow(("CSAMCodePageInvalidate %VGv\n", GCPtr));
1942 /** @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. */
1943 csamFlushPage(pVM, GCPtr, false /* don't remove page! */);
1944 fInCSAMCodePageInvalidate = false;
1945 return VINF_SUCCESS;
1946}
1947
1948/**
1949 * Check if the current instruction has already been checked before
1950 *
1951 * @returns VBox status code. (trap handled or not)
1952 * @param pVM The VM to operate on.
1953 * @param pInstr Instruction pointer
1954 * @param pPage CSAM patch structure pointer
1955 */
1956bool csamIsCodeScanned(PVM pVM, RTGCPTR pInstr, PCSAMPAGE *pPage)
1957{
1958 PCSAMPAGEREC pPageRec;
1959 uint32_t offset;
1960
1961 STAM_PROFILE_START(&pVM->csam.s.StatTimeCheckAddr, a);
1962
1963 offset = pInstr & PAGE_OFFSET_MASK;
1964 pInstr = pInstr & PAGE_BASE_GC_MASK;
1965
1966 Assert(pPage);
1967
1968 if (*pPage && (*pPage)->pPageGC == pInstr)
1969 {
1970 if ((*pPage)->pBitmap == NULL || ASMBitTest((*pPage)->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 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1977 return false;
1978 }
1979
1980 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstr);
1981 if (pPageRec)
1982 {
1983 if (pPage) *pPage= &pPageRec->page;
1984 if (pPageRec->page.pBitmap == NULL || ASMBitTest(pPageRec->page.pBitmap, offset))
1985 {
1986 STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
1987 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1988 return true;
1989 }
1990 }
1991 else
1992 {
1993 if (pPage) *pPage = NULL;
1994 }
1995 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1996 return false;
1997}
1998
1999/**
2000 * Mark an instruction in a page as scanned/not scanned
2001 *
2002 * @param pVM The VM to operate on.
2003 * @param pPage Patch structure pointer
2004 * @param pInstr Instruction pointer
2005 * @param opsize Instruction size
2006 * @param fScanned Mark as scanned or not
2007 */
2008static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTGCPTR pInstr, uint32_t opsize, bool fScanned)
2009{
2010 LogFlow(("csamMarkCodeAsScanned %VGv opsize=%d\n", pInstr, opsize));
2011 CSAMMarkPage(pVM, pInstr, fScanned);
2012
2013 /** @todo should recreate empty bitmap if !fScanned */
2014 if (pPage->pBitmap == NULL)
2015 return;
2016
2017 if (fScanned)
2018 {
2019 // retn instructions can be scanned more than once
2020 if (ASMBitTest(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK) == 0)
2021 {
2022 pPage->uSize += opsize;
2023 STAM_COUNTER_ADD(&pVM->csam.s.StatNrInstr, 1);
2024 }
2025 if (pPage->uSize >= PAGE_SIZE)
2026 {
2027 Log(("Scanned full page (%VGv) -> free bitmap\n", pInstr & PAGE_BASE_GC_MASK));
2028 MMR3HeapFree(pPage->pBitmap);
2029 pPage->pBitmap = NULL;
2030 }
2031 else
2032 ASMBitSet(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2033 }
2034 else
2035 ASMBitClear(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2036}
2037
2038/**
2039 * Mark an instruction in a page as scanned/not scanned
2040 *
2041 * @returns VBox status code.
2042 * @param pVM The VM to operate on.
2043 * @param pInstr Instruction pointer
2044 * @param opsize Instruction size
2045 * @param fScanned Mark as scanned or not
2046 */
2047CSAMR3DECL(int) CSAMR3MarkCode(PVM pVM, RTGCPTR pInstr, uint32_t opsize, bool fScanned)
2048{
2049 PCSAMPAGE pPage = 0;
2050
2051 Assert(!fScanned); /* other case not implemented. */
2052 Assert(!PATMIsPatchGCAddr(pVM, pInstr));
2053
2054 if (csamIsCodeScanned(pVM, pInstr, &pPage) == false)
2055 {
2056 Assert(fScanned == true); /* other case should not be possible */
2057 return VINF_SUCCESS;
2058 }
2059
2060 Log(("CSAMR3MarkCode: %VGv size=%d fScanned=%d\n", pInstr, opsize, fScanned));
2061 csamMarkCode(pVM, pPage, pInstr, opsize, fScanned);
2062 return VINF_SUCCESS;
2063}
2064
2065
2066/**
2067 * Scan and analyse code
2068 *
2069 * @returns VBox status code.
2070 * @param pVM The VM to operate on.
2071 * @param Sel selector
2072 * @param pHiddenSel The hidden selector register.
2073 * @param pInstrGC Instruction pointer
2074 */
2075CSAMR3DECL(int) CSAMR3CheckCodeEx(PVM pVM, RTSEL Sel, CPUMSELREGHID *pHiddenSel, RTGCPTR pInstrGC)
2076{
2077 if (EMIsRawRing0Enabled(pVM) == false || PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2078 {
2079 // No use
2080 return VINF_SUCCESS;
2081 }
2082
2083 if (CSAMIsEnabled(pVM))
2084 {
2085 X86EFLAGS fakeflags;
2086
2087 /* we're not in v86 mode here */
2088 fakeflags.u32 = 0;
2089
2090 bool fCode32 = SELMIsSelector32Bit(pVM, fakeflags, Sel, pHiddenSel);
2091
2092 //assuming 32 bits code for now
2093 Assert(fCode32); NOREF(fCode32);
2094
2095 pInstrGC = SELMToFlat(pVM, fakeflags, Sel, pHiddenSel, pInstrGC);
2096
2097 return CSAMR3CheckCode(pVM, pInstrGC);
2098 }
2099 return VINF_SUCCESS;
2100}
2101
2102/**
2103 * Scan and analyse code
2104 *
2105 * @returns VBox status code.
2106 * @param pVM The VM to operate on.
2107 * @param pInstrGC Instruction pointer (0:32 virtual address)
2108 */
2109CSAMR3DECL(int) CSAMR3CheckCode(PVM pVM, RTGCPTR pInstrGC)
2110{
2111 int rc;
2112 PCSAMPAGE pPage = NULL;
2113
2114 if (EMIsRawRing0Enabled(pVM) == false || PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2115 {
2116 // No use
2117 return VINF_SUCCESS;
2118 }
2119
2120 if (CSAMIsEnabled(pVM))
2121 {
2122 // Cache record for PATMGCVirtToHCVirt
2123 CSAMP2GLOOKUPREC cacheRec = {0};
2124
2125 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2126 rc = csamAnalyseCallCodeStream(pVM, pInstrGC, pInstrGC, true /* 32 bits code */, CSAMR3AnalyseCallback, pPage, &cacheRec);
2127 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2128 if (rc != VINF_SUCCESS)
2129 {
2130 Log(("csamAnalyseCodeStream failed with %d\n", rc));
2131 return rc;
2132 }
2133 }
2134 return VINF_SUCCESS;
2135}
2136
2137/**
2138 * Flush dirty code pages
2139 *
2140 * @returns VBox status code.
2141 * @param pVM The VM to operate on.
2142 */
2143static int csamR3FlushDirtyPages(PVM pVM)
2144{
2145 STAM_PROFILE_START(&pVM->csam.s.StatFlushDirtyPages, a);
2146
2147 for (uint32_t i=0;i<pVM->csam.s.cDirtyPages;i++)
2148 {
2149 int rc;
2150 PCSAMPAGEREC pPageRec;
2151 RTGCPTR GCPtr = pVM->csam.s.pvDirtyBasePage[i];
2152
2153 GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2154
2155 /* Notify the recompiler that this page has been changed. */
2156 REMR3NotifyCodePageChanged(pVM, GCPtr);
2157
2158 /* Enable write protection again. (use the fault address as it might be an alias) */
2159 rc = PGMShwModifyPage(pVM, pVM->csam.s.pvDirtyFaultPage[i], 1, 0, ~(uint64_t)X86_PTE_RW);
2160 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
2161
2162 Log(("CSAMR3FlushDirtyPages: flush %VGv (modifypage rc=%Vrc)\n", pVM->csam.s.pvDirtyBasePage[i], rc));
2163
2164 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
2165 if (pPageRec && pPageRec->page.enmTag == CSAM_TAG_REM)
2166 {
2167 uint64_t fFlags;
2168
2169 rc = PGMGstGetPage(pVM, GCPtr, &fFlags, NULL);
2170 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
2171 if ( rc == VINF_SUCCESS
2172 && (fFlags & X86_PTE_US))
2173 {
2174 /* We don't care about user pages. */
2175 csamRemovePageRecord(pVM, GCPtr);
2176 STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
2177 }
2178 }
2179 }
2180 pVM->csam.s.cDirtyPages = 0;
2181 STAM_PROFILE_STOP(&pVM->csam.s.StatFlushDirtyPages, a);
2182 return VINF_SUCCESS;
2183}
2184
2185/**
2186 * Flush potential new code pages
2187 *
2188 * @returns VBox status code.
2189 * @param pVM The VM to operate on.
2190 */
2191static int csamR3FlushCodePages(PVM pVM)
2192{
2193 for (uint32_t i=0;i<pVM->csam.s.cPossibleCodePages;i++)
2194 {
2195 RTGCPTR GCPtr = pVM->csam.s.pvPossibleCodePage[i];
2196
2197 GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2198
2199 Log(("csamR3FlushCodePages: %VGv\n", GCPtr));
2200 PGMShwSetPage(pVM, GCPtr, 1, 0);
2201 /* Resync the page to make sure instruction fetch will fault */
2202 CSAMMarkPage(pVM, GCPtr, false);
2203 }
2204 pVM->csam.s.cPossibleCodePages = 0;
2205 return VINF_SUCCESS;
2206}
2207
2208/**
2209 * Perform any pending actions
2210 *
2211 * @returns VBox status code.
2212 * @param pVM The VM to operate on.
2213 */
2214CSAMR3DECL(int) CSAMR3DoPendingAction(PVM pVM)
2215{
2216 csamR3FlushDirtyPages(pVM);
2217 csamR3FlushCodePages(pVM);
2218
2219 VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
2220 return VINF_SUCCESS;
2221}
2222
2223/**
2224 * Analyse interrupt and trap gates
2225 *
2226 * @returns VBox status code.
2227 * @param pVM The VM to operate on.
2228 * @param iGate Start gate
2229 * @param cGates Number of gates to check
2230 */
2231CSAMR3DECL(int) CSAMR3CheckGates(PVM pVM, uint32_t iGate, uint32_t cGates)
2232{
2233 uint16_t cbIDT;
2234 RTGCPTR GCPtrIDT = CPUMGetGuestIDTR(pVM, &cbIDT);
2235 uint32_t iGateEnd;
2236 uint32_t maxGates;
2237 VBOXIDTE aIDT[256];
2238 PVBOXIDTE pGuestIdte;
2239 int rc;
2240
2241 if (EMIsRawRing0Enabled(pVM) == false)
2242 {
2243 /* Enabling interrupt gates only works when raw ring 0 is enabled. */
2244 //AssertFailed();
2245 return VINF_SUCCESS;
2246 }
2247
2248 /* We only check all gates once during a session */
2249 if ( !pVM->csam.s.fGatesChecked
2250 && cGates != 256)
2251 return VINF_SUCCESS; /* too early */
2252
2253 /* We only check all gates once during a session */
2254 if ( pVM->csam.s.fGatesChecked
2255 && cGates != 1)
2256 return VINF_SUCCESS; /* ignored */
2257
2258 Assert(cGates <= 256);
2259 if (!GCPtrIDT || cGates > 256)
2260 return VERR_INVALID_PARAMETER;
2261
2262 if (cGates != 1)
2263 {
2264 pVM->csam.s.fGatesChecked = true;
2265 for (unsigned i=0;i<RT_ELEMENTS(pVM->csam.s.pvCallInstruction);i++)
2266 {
2267 RTGCPTR pHandler = pVM->csam.s.pvCallInstruction[i];
2268
2269 if (pHandler)
2270 {
2271 CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2272 PCSAMPAGE pPage = NULL;
2273
2274 Log(("CSAMCheckGates: checking previous call instruction %VGv\n", pHandler));
2275 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2276 rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2277 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2278 if (rc != VINF_SUCCESS)
2279 {
2280 Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2281 continue;
2282 }
2283 }
2284 }
2285 }
2286
2287 /* Determine valid upper boundary. */
2288 maxGates = (cbIDT+1) / sizeof(VBOXIDTE);
2289 Assert(iGate < maxGates);
2290 if (iGate > maxGates)
2291 return VERR_INVALID_PARAMETER;
2292
2293 if (iGate + cGates > maxGates)
2294 cGates = maxGates - iGate;
2295
2296 GCPtrIDT = GCPtrIDT + iGate * sizeof(VBOXIDTE);
2297 iGateEnd = iGate + cGates;
2298
2299 STAM_PROFILE_START(&pVM->csam.s.StatCheckGates, a);
2300
2301 /*
2302 * Get IDT entries.
2303 */
2304 if (PAGE_ADDRESS(GCPtrIDT) == PAGE_ADDRESS(GCPtrIDT+cGates*sizeof(VBOXIDTE)))
2305 {
2306 /* Just convert the IDT address to a HC pointer. The whole IDT fits in one page. */
2307 rc = PGMPhysGCPtr2HCPtr(pVM, GCPtrIDT, (PRTHCPTR)&pGuestIdte);
2308 if (VBOX_FAILURE(rc))
2309 {
2310 AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2311 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2312 return rc;
2313 }
2314 }
2315 else
2316 {
2317 /* Slow method when it crosses a page boundary. */
2318 rc = PGMPhysReadGCPtr(pVM, aIDT, GCPtrIDT, cGates*sizeof(VBOXIDTE));
2319 if (VBOX_FAILURE(rc))
2320 {
2321 AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2322 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2323 return rc;
2324 }
2325 pGuestIdte = &aIDT[0];
2326 }
2327
2328 for (/*iGate*/; iGate<iGateEnd; iGate++, pGuestIdte++)
2329 {
2330 Assert(TRPMR3GetGuestTrapHandler(pVM, iGate) == TRPM_INVALID_HANDLER);
2331
2332 if ( pGuestIdte->Gen.u1Present
2333 && (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32 || pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_INT_32)
2334 && (pGuestIdte->Gen.u2DPL == 3 || pGuestIdte->Gen.u2DPL == 0)
2335 )
2336 {
2337 RTGCPTR pHandler;
2338 CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2339 PCSAMPAGE pPage = NULL;
2340 X86EFLAGS fakeflags;
2341 SELMSELINFO selInfo;
2342
2343 /* we're not in v86 mode here */
2344 fakeflags.u32 = 0;
2345
2346 pHandler = (pGuestIdte->Gen.u16OffsetHigh << 16) | pGuestIdte->Gen.u16OffsetLow;
2347 pHandler = SELMToFlat(pVM, fakeflags, pGuestIdte->Gen.u16SegSel, 0, pHandler);
2348
2349 rc = SELMR3GetSelectorInfo(pVM, pGuestIdte->Gen.u16SegSel, &selInfo);
2350 if ( VBOX_FAILURE(rc)
2351 || selInfo.GCPtrBase != 0
2352 || selInfo.cbLimit != ~0U
2353 )
2354 {
2355 /* Refuse to patch a handler whose idt cs selector isn't wide open. */
2356 Log(("CSAMCheckGates: check gate %d failed due to rc %Vrc GCPtrBase=%VGv limit=%x\n", iGate, rc, selInfo.GCPtrBase, selInfo.cbLimit));
2357 continue;
2358 }
2359
2360
2361 if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2362 {
2363 Log(("CSAMCheckGates: check trap gate %d at %04X:%08X (flat %VGv)\n", iGate, pGuestIdte->Gen.u16SegSel, (pGuestIdte->Gen.u16OffsetHigh << 16) | pGuestIdte->Gen.u16OffsetLow, pHandler));
2364 }
2365 else
2366 {
2367 Log(("CSAMCheckGates: check interrupt gate %d at %04X:%08X (flat %VGv)\n", iGate, pGuestIdte->Gen.u16SegSel, (pGuestIdte->Gen.u16OffsetHigh << 16) | pGuestIdte->Gen.u16OffsetLow, pHandler));
2368 }
2369
2370 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2371 rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2372 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2373 if (rc != VINF_SUCCESS)
2374 {
2375 Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2376 continue;
2377 }
2378 /* OpenBSD guest specific patch test. */
2379 if (iGate >= 0x20)
2380 {
2381 PCPUMCTX pCtx;
2382 DISCPUSTATE cpu;
2383 RTGCUINTPTR aOpenBsdPushCSOffset[3] = {0x03, /* OpenBSD 3.7 & 3.8 */
2384 0x2B, /* OpenBSD 4.0 installation ISO */
2385 0x2F}; /* OpenBSD 4.0 after install */
2386
2387 rc = CPUMQueryGuestCtxPtr(pVM, &pCtx);
2388 AssertRC(rc); /* can't fail */
2389
2390 for (unsigned i=0;i<ELEMENTS(aOpenBsdPushCSOffset);i++)
2391 {
2392 rc = CPUMR3DisasmInstrCPU(pVM, pCtx, pHandler - aOpenBsdPushCSOffset[i], &cpu, NULL);
2393 if ( rc == VINF_SUCCESS
2394 && cpu.pCurInstr->opcode == OP_PUSH
2395 && cpu.pCurInstr->param1 == OP_PARM_REG_CS)
2396 {
2397 rc = PATMR3InstallPatch(pVM, pHandler - aOpenBsdPushCSOffset[i], PATMFL_CODE32 | PATMFL_GUEST_SPECIFIC);
2398 if (VBOX_SUCCESS(rc))
2399 Log(("Installed OpenBSD interrupt handler prefix instruction (push cs) patch\n"));
2400 }
2401 }
2402 }
2403
2404 /* Trap gates and certain interrupt gates. */
2405 uint32_t fPatchFlags = PATMFL_CODE32 | PATMFL_IDTHANDLER;
2406
2407 if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2408 fPatchFlags |= PATMFL_TRAPHANDLER;
2409 else
2410 fPatchFlags |= PATMFL_INTHANDLER;
2411
2412 switch (iGate) {
2413 case 8:
2414 case 10:
2415 case 11:
2416 case 12:
2417 case 13:
2418 case 14:
2419 case 17:
2420 fPatchFlags |= PATMFL_TRAPHANDLER_WITH_ERRORCODE;
2421 break;
2422 default:
2423 /* No error code. */
2424 break;
2425 }
2426
2427 Log(("Installing %s gate handler for 0x%X at %VGv\n", (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32) ? "trap" : "intr", iGate, pHandler));
2428
2429 rc = PATMR3InstallPatch(pVM, pHandler, fPatchFlags);
2430 if (VBOX_SUCCESS(rc) || rc == VERR_PATM_ALREADY_PATCHED)
2431 {
2432 Log(("Gate handler 0x%X is SAFE!\n", iGate));
2433
2434 RTGCPTR pNewHandlerGC = PATMR3QueryPatchGCPtr(pVM, pHandler);
2435 if (pNewHandlerGC)
2436 {
2437 rc = TRPMR3SetGuestTrapHandler(pVM, iGate, pNewHandlerGC);
2438 if (VBOX_FAILURE(rc))
2439 Log(("TRPMR3SetGuestTrapHandler %d failed with %Vrc\n", iGate, rc));
2440 }
2441 }
2442 }
2443 } /* for */
2444 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2445 return VINF_SUCCESS;
2446}
2447
2448/**
2449 * Record previous call instruction addresses
2450 *
2451 * @returns VBox status code.
2452 * @param pVM The VM to operate on.
2453 * @param GCPtrCall Call address
2454 */
2455CSAMR3DECL(int) CSAMR3RecordCallAddress(PVM pVM, RTGCPTR GCPtrCall)
2456{
2457 for (unsigned i=0;i<RT_ELEMENTS(pVM->csam.s.pvCallInstruction);i++)
2458 {
2459 if (pVM->csam.s.pvCallInstruction[i] == GCPtrCall)
2460 return VINF_SUCCESS;
2461 }
2462
2463 Log(("CSAMR3RecordCallAddress %VGv\n", GCPtrCall));
2464
2465 pVM->csam.s.pvCallInstruction[pVM->csam.s.iCallInstruction++] = GCPtrCall;
2466 if (pVM->csam.s.iCallInstruction >= RT_ELEMENTS(pVM->csam.s.pvCallInstruction))
2467 pVM->csam.s.iCallInstruction = 0;
2468
2469 return VINF_SUCCESS;
2470}
2471
2472
2473/**
2474 * Query CSAM state (enabled/disabled)
2475 *
2476 * @returns 0 - disabled, 1 - enabled
2477 * @param pVM The VM to operate on.
2478 */
2479CSAMR3DECL(int) CSAMR3IsEnabled(PVM pVM)
2480{
2481 return pVM->fCSAMEnabled;
2482}
2483
2484#ifdef VBOX_WITH_DEBUGGER
2485/**
2486 * The '.csamoff' command.
2487 *
2488 * @returns VBox status.
2489 * @param pCmd Pointer to the command descriptor (as registered).
2490 * @param pCmdHlp Pointer to command helper functions.
2491 * @param pVM Pointer to the current VM (if any).
2492 * @param paArgs Pointer to (readonly) array of arguments.
2493 * @param cArgs Number of arguments in the array.
2494 */
2495static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2496{
2497 /*
2498 * Validate input.
2499 */
2500 if (!pVM)
2501 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2502
2503 CSAMDisableScanning(pVM);
2504 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning disabled\n");
2505}
2506
2507/**
2508 * The '.csamon' command.
2509 *
2510 * @returns VBox status.
2511 * @param pCmd Pointer to the command descriptor (as registered).
2512 * @param pCmdHlp Pointer to command helper functions.
2513 * @param pVM Pointer to the current VM (if any).
2514 * @param paArgs Pointer to (readonly) array of arguments.
2515 * @param cArgs Number of arguments in the array.
2516 */
2517static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2518{
2519 /*
2520 * Validate input.
2521 */
2522 if (!pVM)
2523 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2524
2525 CSAMEnableScanning(pVM);
2526 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning enabled\n");
2527}
2528#endif
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