VirtualBox

source: vbox/trunk/src/VBox/VMM/PATM/CSAM.cpp@ 5198

Last change on this file since 5198 was 5198, checked in by vboxsync, 17 years ago

Experiment with call recording for CSAM

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1/* $Id: CSAM.cpp 5198 2007-10-09 12:32:03Z 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 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
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 {
1195 addr = CSAMResolveBranch(&cpu, pCurInstrGC);
1196 if (addr == 0)
1197 {
1198 Log(("We don't support far jumps here!! (%08X)\n", cpu.param1.flags));
1199 rc = VINF_SUCCESS;
1200 break;
1201 }
1202 Assert(!PATMIsPatchGCAddr(pVM, addr));
1203
1204 /* If the target address lies in a patch generated jump, then special action needs to be taken. */
1205 PATMR3DetectConflict(pVM, pCurInstrGC, addr);
1206
1207 /* Same page? */
1208 if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pCurInstrGC ))
1209 {
1210 if (!PGMGstIsPagePresent(pVM, addr))
1211 {
1212 Log(("Page for current instruction %VGv is not present!!\n", addr));
1213 rc = VWRN_CONTINUE_ANALYSIS;
1214 goto next_please;
1215 }
1216
1217 /* All is fine, let's continue. */
1218 csamR3CheckPageRecord(pVM, addr);
1219 }
1220
1221 pJmpPage = NULL;
1222 if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1223 {
1224 if (pJmpPage == NULL)
1225 {
1226 /* New branch target; let's take a look at it. */
1227 pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1228 if (pJmpPage == NULL)
1229 {
1230 rc = VERR_NO_MEMORY;
1231 goto done;
1232 }
1233 Assert(pPage);
1234 }
1235 if (cpu.pCurInstr->opcode == OP_CALL)
1236 rc = csamAnalyseCallCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1237 else
1238 rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1239
1240 if (rc != VINF_SUCCESS) {
1241 goto done;
1242 }
1243 }
1244 if (cpu.pCurInstr->opcode == OP_JMP)
1245 {//unconditional jump; return to caller
1246 rc = VINF_SUCCESS;
1247 goto done;
1248 }
1249
1250 rc = VWRN_CONTINUE_ANALYSIS;
1251 } //if ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1252#ifdef CSAM_SCAN_JUMP_TABLE
1253 else
1254 if ( cpu.pCurInstr->opcode == OP_JMP
1255 && (cpu.param1.flags & (USE_DISPLACEMENT32|USE_INDEX|USE_SCALE)) == (USE_DISPLACEMENT32|USE_INDEX|USE_SCALE)
1256 )
1257 {
1258 RTGCPTR pJumpTableGC = (RTGCPTR)cpu.param1.disp32;
1259 uint8_t *pJumpTableHC;
1260 int rc2;
1261
1262 Log(("Jump through jump table\n"));
1263
1264 rc2 = PGMPhysGCPtr2HCPtr(pVM, pJumpTableGC, (PRTHCPTR)&pJumpTableHC);
1265 if (rc2 == VINF_SUCCESS)
1266 {
1267 for (uint32_t i=0;i<2;i++)
1268 {
1269 uint64_t fFlags;
1270
1271 addr = pJumpTableGC + cpu.param1.scale * i;
1272 /* Same page? */
1273 if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pJumpTableGC))
1274 break;
1275
1276 addr = *(RTGCPTR *)(pJumpTableHC + cpu.param1.scale * i);
1277
1278 rc2 = PGMGstGetPage(pVM, addr, &fFlags, NULL);
1279 if ( rc2 != VINF_SUCCESS
1280 || (fFlags & X86_PTE_US)
1281 || !(fFlags & X86_PTE_P)
1282 )
1283 break;
1284
1285 Log(("Jump to %VGv\n", addr));
1286
1287 pJmpPage = NULL;
1288 if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1289 {
1290 if (pJmpPage == NULL)
1291 {
1292 /* New branch target; let's take a look at it. */
1293 pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1294 if (pJmpPage == NULL)
1295 {
1296 rc = VERR_NO_MEMORY;
1297 goto done;
1298 }
1299 Assert(pPage);
1300 }
1301 rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1302 if (rc != VINF_SUCCESS) {
1303 goto done;
1304 }
1305 }
1306 }
1307 }
1308 }
1309#endif
1310 if (rc != VWRN_CONTINUE_ANALYSIS) {
1311 break; //done!
1312 }
1313next_please:
1314 if (cpu.pCurInstr->opcode == OP_JMP)
1315 {
1316 rc = VINF_SUCCESS;
1317 goto done;
1318 }
1319 pCurInstrGC += opsize;
1320 }
1321done:
1322 pCacheRec->depth--;
1323 return rc;
1324}
1325
1326
1327/**
1328 * Calculates the 64 bits hash value for the current page
1329 *
1330 * @returns hash value
1331 * @param pVM The VM to operate on.
1332 * @param pInstr Page address
1333 */
1334uint64_t csamR3CalcPageHash(PVM pVM, RTGCPTR pInstr)
1335{
1336 uint64_t hash = 0;
1337 uint32_t val[5];
1338 int rc;
1339
1340 Assert((pInstr & PAGE_OFFSET_MASK) == 0);
1341
1342 rc = PGMPhysReadGCPtr(pVM, &val[0], pInstr, sizeof(val[0]));
1343 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1344 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1345 {
1346 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1347 return ~0ULL;
1348 }
1349
1350 rc = PGMPhysReadGCPtr(pVM, &val[1], pInstr+1024, sizeof(val[0]));
1351 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1352 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1353 {
1354 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1355 return ~0ULL;
1356 }
1357
1358 rc = PGMPhysReadGCPtr(pVM, &val[2], pInstr+2048, sizeof(val[0]));
1359 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1360 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1361 {
1362 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1363 return ~0ULL;
1364 }
1365
1366 rc = PGMPhysReadGCPtr(pVM, &val[3], pInstr+3072, sizeof(val[0]));
1367 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1368 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1369 {
1370 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1371 return ~0ULL;
1372 }
1373
1374 rc = PGMPhysReadGCPtr(pVM, &val[4], pInstr+4092, sizeof(val[0]));
1375 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1376 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1377 {
1378 Log(("csamR3CalcPageHash: page %VGv not present!!\n", pInstr));
1379 return ~0ULL;
1380 }
1381
1382 // don't want to get division by zero traps
1383 val[2] |= 1;
1384 val[4] |= 1;
1385
1386 hash = (uint64_t)val[0] * (uint64_t)val[1] / (uint64_t)val[2] + (val[3]%val[4]);
1387 return (hash == ~0ULL) ? hash - 1 : hash;
1388}
1389
1390
1391/**
1392 * Notify CSAM of a page flush
1393 *
1394 * @returns VBox status code
1395 * @param pVM The VM to operate on.
1396 * @param addr GC address of the page to flush
1397 * @param fRemovePage Page removal flag
1398 */
1399static int csamFlushPage(PVM pVM, RTGCPTR addr, bool fRemovePage)
1400{
1401 PCSAMPAGEREC pPageRec;
1402 int rc;
1403 RTGCPHYS GCPhys = 0;
1404 uint64_t fFlags = 0;
1405
1406 if (!CSAMIsEnabled(pVM))
1407 return VINF_SUCCESS;
1408
1409 STAM_PROFILE_START(&pVM->csam.s.StatTimeFlushPage, a);
1410
1411 addr = addr & PAGE_BASE_GC_MASK;
1412
1413 /*
1414 * Note: searching for the page in our tree first is more expensive (skipped flushes are two orders of magnitude more common)
1415 */
1416 if (pVM->csam.s.pPageTree == NULL)
1417 {
1418 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1419 return VWRN_CSAM_PAGE_NOT_FOUND;
1420 }
1421
1422 rc = PGMGstGetPage(pVM, addr, &fFlags, &GCPhys);
1423 /* Returned at a very early stage (no paging yet presumably). */
1424 if (rc == VERR_NOT_SUPPORTED)
1425 {
1426 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1427 return rc;
1428 }
1429
1430 if (VBOX_SUCCESS(rc))
1431 {
1432 if ( (fFlags & X86_PTE_US)
1433 || rc == VERR_PGM_PHYS_PAGE_RESERVED
1434 )
1435 {
1436 /* User page -> not relevant for us. */
1437 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1438 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1439 return VINF_SUCCESS;
1440 }
1441 }
1442 else
1443 if (rc != VERR_PAGE_NOT_PRESENT && rc != VERR_PAGE_TABLE_NOT_PRESENT)
1444 AssertMsgFailed(("PGMR3GetPage %VGv failed with %Vrc\n", addr, rc));
1445
1446 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1447 if (pPageRec)
1448 {
1449 if ( GCPhys == pPageRec->page.GCPhys
1450 && (fFlags & X86_PTE_P))
1451 {
1452 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1453 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1454 return VINF_SUCCESS;
1455 }
1456
1457 Log(("CSAMR3FlushPage: page %VGv has changed -> FLUSH (rc=%Vrc) (Phys: %VGp vs %VGp)\n", addr, rc, GCPhys, pPageRec->page.GCPhys));
1458
1459 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushes, 1);
1460
1461 if (fRemovePage)
1462 csamRemovePageRecord(pVM, addr);
1463 else
1464 {
1465 CSAMMarkPage(pVM, addr, false);
1466 pPageRec->page.GCPhys = 0;
1467 pPageRec->page.fFlags = 0;
1468 rc = PGMGstGetPage(pVM, addr, &pPageRec->page.fFlags, &pPageRec->page.GCPhys);
1469 if (rc == VINF_SUCCESS)
1470 pPageRec->page.u64Hash = csamR3CalcPageHash(pVM, addr);
1471
1472 if (pPageRec->page.pBitmap == NULL)
1473 {
1474 pPageRec->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, CSAM_PAGE_BITMAP_SIZE);
1475 Assert(pPageRec->page.pBitmap);
1476 if (pPageRec->page.pBitmap == NULL)
1477 return VERR_NO_MEMORY;
1478 }
1479 else
1480 memset(pPageRec->page.pBitmap, 0, CSAM_PAGE_BITMAP_SIZE);
1481 }
1482
1483
1484 /*
1485 * Inform patch manager about the flush; no need to repeat the above check twice.
1486 */
1487 PATMR3FlushPage(pVM, addr);
1488
1489 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1490 return VINF_SUCCESS;
1491 }
1492 else
1493 {
1494 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1495 return VWRN_CSAM_PAGE_NOT_FOUND;
1496 }
1497}
1498
1499/**
1500 * Notify CSAM of a page flush
1501 *
1502 * @returns VBox status code
1503 * @param pVM The VM to operate on.
1504 * @param addr GC address of the page to flush
1505 */
1506CSAMR3DECL(int) CSAMR3FlushPage(PVM pVM, RTGCPTR addr)
1507{
1508 return csamFlushPage(pVM, addr, true /* remove page record */);
1509}
1510
1511/**
1512 * Remove a CSAM monitored page. Use with care!
1513 *
1514 * @returns VBox status code
1515 * @param pVM The VM to operate on.
1516 * @param addr GC address of the page to flush
1517 */
1518CSAMR3DECL(int) CSAMR3RemovePage(PVM pVM, RTGCPTR addr)
1519{
1520 PCSAMPAGEREC pPageRec;
1521 int rc;
1522
1523 addr = addr & PAGE_BASE_GC_MASK;
1524
1525 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1526 if (pPageRec)
1527 {
1528 rc = csamRemovePageRecord(pVM, addr);
1529 if (VBOX_SUCCESS(rc))
1530 PATMR3FlushPage(pVM, addr);
1531 return VINF_SUCCESS;
1532 }
1533 return VWRN_CSAM_PAGE_NOT_FOUND;
1534}
1535
1536/**
1537 * Check a page record in case a page has been changed
1538 *
1539 * @returns VBox status code. (trap handled or not)
1540 * @param pVM The VM to operate on.
1541 * @param pInstrGC GC instruction pointer
1542 */
1543int csamR3CheckPageRecord(PVM pVM, RTGCPTR pInstrGC)
1544{
1545 PCSAMPAGEREC pPageRec;
1546 uint64_t u64hash;
1547
1548 pInstrGC = pInstrGC & PAGE_BASE_GC_MASK;
1549
1550 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstrGC);
1551 if (pPageRec)
1552 {
1553 u64hash = csamR3CalcPageHash(pVM, pInstrGC);
1554 if (u64hash != pPageRec->page.u64Hash)
1555 csamFlushPage(pVM, pInstrGC, false /* don't remove page record */);
1556 }
1557 else
1558 return VWRN_CSAM_PAGE_NOT_FOUND;
1559
1560 return VINF_SUCCESS;
1561}
1562
1563/**
1564 * Returns monitor description based on CSAM tag
1565 *
1566 * @return description string
1567 * @param enmTag Owner tag
1568 */
1569const char *csamGetMonitorDescription(CSAMTAG enmTag)
1570{
1571 if (enmTag == CSAM_TAG_PATM)
1572 return "CSAM-PATM self-modifying code monitor handler";
1573 else
1574 if (enmTag == CSAM_TAG_REM)
1575 return "CSAM-REM self-modifying code monitor handler";
1576 Assert(enmTag == CSAM_TAG_CSAM);
1577 return "CSAM self-modifying code monitor handler";
1578}
1579
1580/**
1581 * Adds page record to our lookup tree
1582 *
1583 * @returns CSAMPAGE ptr or NULL if failure
1584 * @param pVM The VM to operate on.
1585 * @param GCPtr Page address
1586 * @param enmTag Owner tag
1587 * @param fCode32 16 or 32 bits code
1588 * @param fMonitorInvalidation Monitor page invalidation flag
1589 */
1590static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTGCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation)
1591{
1592 PCSAMPAGEREC pPage;
1593 int rc;
1594 bool ret;
1595
1596 Log(("New page record for %VGv\n", GCPtr & PAGE_BASE_GC_MASK));
1597
1598 pPage = (PCSAMPAGEREC)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, sizeof(CSAMPAGEREC));
1599 if (pPage == NULL)
1600 {
1601 AssertMsgFailed(("csamCreatePageRecord: Out of memory!!!!\n"));
1602 return NULL;
1603 }
1604 /* Round down to page boundary. */
1605 GCPtr = (GCPtr & PAGE_BASE_GC_MASK);
1606 pPage->Core.Key = (AVLPVKEY)GCPtr;
1607 pPage->page.pPageGC = GCPtr;
1608 pPage->page.fCode32 = fCode32;
1609 pPage->page.fMonitorInvalidation = fMonitorInvalidation;
1610 pPage->page.enmTag = enmTag;
1611 pPage->page.fMonitorActive = false;
1612 pPage->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, PAGE_SIZE/sizeof(uint8_t));
1613 rc = PGMGstGetPage(pVM, GCPtr, &pPage->page.fFlags, &pPage->page.GCPhys);
1614 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1615
1616 pPage->page.u64Hash = csamR3CalcPageHash(pVM, GCPtr);
1617 ret = RTAvlPVInsert(&pVM->csam.s.pPageTree, &pPage->Core);
1618 Assert(ret);
1619
1620#ifdef CSAM_MONITOR_CODE_PAGES
1621 AssertRelease(!fInCSAMCodePageInvalidate);
1622
1623 switch (enmTag)
1624 {
1625 case CSAM_TAG_PATM:
1626 case CSAM_TAG_REM:
1627#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1628 case CSAM_TAG_CSAM:
1629#endif
1630 {
1631 int rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GCPtr, GCPtr + (PAGE_SIZE - 1) /* inclusive! */,
1632 (fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1633 csamGetMonitorDescription(enmTag));
1634 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VGv failed with %Vrc\n", GCPtr, rc));
1635 if (VBOX_FAILURE(rc))
1636 Log(("PGMR3HandlerVirtualRegisterEx for %VGv failed with %Vrc\n", GCPtr, rc));
1637
1638 /* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1639
1640 /* Prefetch it in case it's not there yet. */
1641 rc = PGMPrefetchPage(pVM, GCPtr);
1642 AssertRC(rc);
1643
1644 rc = PGMShwModifyPage(pVM, GCPtr, 1, 0, ~(uint64_t)X86_PTE_RW);
1645 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1646
1647 pPage->page.fMonitorActive = true;
1648 STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1649 break;
1650 }
1651 default:
1652 break; /* to shut up GCC */
1653 }
1654
1655 Log(("csamCreatePageRecord %VGv HCPhys=%VGp\n", GCPtr, pPage->page.GCPhys));
1656
1657#ifdef VBOX_WITH_STATISTICS
1658 switch (enmTag)
1659 {
1660 case CSAM_TAG_CSAM:
1661 STAM_COUNTER_INC(&pVM->csam.s.StatPageCSAM);
1662 break;
1663 case CSAM_TAG_PATM:
1664 STAM_COUNTER_INC(&pVM->csam.s.StatPagePATM);
1665 break;
1666 case CSAM_TAG_REM:
1667 STAM_COUNTER_INC(&pVM->csam.s.StatPageREM);
1668 break;
1669 default:
1670 break; /* to shut up GCC */
1671 }
1672#endif
1673
1674#endif
1675
1676 STAM_COUNTER_INC(&pVM->csam.s.StatNrPages);
1677 if (fMonitorInvalidation)
1678 STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1679
1680 return &pPage->page;
1681}
1682
1683/**
1684 * Monitors a code page (if not already monitored)
1685 *
1686 * @returns VBox status code
1687 * @param pVM The VM to operate on.
1688 * @param pPageAddrGC The page to monitor
1689 * @param enmTag Monitor tag
1690 */
1691CSAMR3DECL(int) CSAMR3MonitorPage(PVM pVM, RTGCPTR pPageAddrGC, CSAMTAG enmTag)
1692{
1693 PCSAMPAGEREC pPageRec = NULL;
1694 int rc;
1695 bool fMonitorInvalidation;
1696
1697 /* Dirty pages must be handled before calling this function!. */
1698 Assert(!pVM->csam.s.cDirtyPages);
1699
1700 if (pVM->csam.s.fScanningStarted == false)
1701 return VINF_SUCCESS; /* too early */
1702
1703 pPageAddrGC &= PAGE_BASE_GC_MASK;
1704
1705 Log(("CSAMR3MonitorPage %VGv %d\n", pPageAddrGC, enmTag));
1706
1707 /** @todo implicit assumption */
1708 fMonitorInvalidation = (enmTag == CSAM_TAG_PATM);
1709
1710 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1711 if (pPageRec == NULL)
1712 {
1713 uint64_t fFlags;
1714
1715 rc = PGMGstGetPage(pVM, pPageAddrGC, &fFlags, NULL);
1716 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1717 if ( rc == VINF_SUCCESS
1718 && (fFlags & X86_PTE_US))
1719 {
1720 /* We don't care about user pages. */
1721 STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
1722 return VINF_SUCCESS;
1723 }
1724
1725 csamCreatePageRecord(pVM, pPageAddrGC, enmTag, true /* 32 bits code */, fMonitorInvalidation);
1726
1727 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1728 Assert(pPageRec);
1729 }
1730 /** @todo reference count */
1731
1732#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1733 Assert(pPageRec->page.fMonitorActive);
1734#endif
1735
1736#ifdef CSAM_MONITOR_CODE_PAGES
1737 if (!pPageRec->page.fMonitorActive)
1738 {
1739 Log(("CSAMR3MonitorPage: activate monitoring for %VGv\n", pPageAddrGC));
1740
1741 rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, pPageAddrGC, pPageAddrGC + (PAGE_SIZE - 1) /* inclusive! */,
1742 (fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1743 csamGetMonitorDescription(enmTag));
1744 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VGv failed with %Vrc\n", pPageAddrGC, rc));
1745 if (VBOX_FAILURE(rc))
1746 Log(("PGMR3HandlerVirtualRegisterEx for %VGv failed with %Vrc\n", pPageAddrGC, rc));
1747
1748 /* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1749
1750 /* Prefetch it in case it's not there yet. */
1751 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1752 AssertRC(rc);
1753
1754 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1755 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1756
1757 STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1758
1759 pPageRec->page.fMonitorActive = true;
1760 pPageRec->page.fMonitorInvalidation = fMonitorInvalidation;
1761 }
1762 else
1763 if ( !pPageRec->page.fMonitorInvalidation
1764 && fMonitorInvalidation)
1765 {
1766 Assert(pPageRec->page.fMonitorActive);
1767 PGMHandlerVirtualChangeInvalidateCallback(pVM, pPageRec->page.pPageGC, CSAMCodePageInvalidate);
1768 pPageRec->page.fMonitorInvalidation = true;
1769 STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1770
1771 /* Prefetch it in case it's not there yet. */
1772 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1773 AssertRC(rc);
1774
1775 /* Make sure it's readonly. Page invalidation may have modified the attributes. */
1776 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1777 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1778 }
1779
1780#if 0 /* def VBOX_STRICT -> very annoying) */
1781 if (pPageRec->page.fMonitorActive)
1782 {
1783 uint64_t fPageShw;
1784 RTHCPHYS GCPhys;
1785 rc = PGMShwGetPage(pVM, pPageAddrGC, &fPageShw, &GCPhys);
1786// AssertMsg( (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1787// || !(fPageShw & X86_PTE_RW)
1788// || (pPageRec->page.GCPhys == 0), ("Shadow page flags for %VGv (%VHp) aren't readonly (%VX64)!!\n", pPageAddrGC, GCPhys, fPageShw));
1789 }
1790#endif
1791
1792 if (pPageRec->page.GCPhys == 0)
1793 {
1794 /* Prefetch it in case it's not there yet. */
1795 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1796 AssertRC(rc);
1797 /* The page was changed behind our back. It won't be made read-only until the next SyncCR3, so force it here. */
1798 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1799 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1800 }
1801#endif /* CSAM_MONITOR_CODE_PAGES */
1802 return VINF_SUCCESS;
1803}
1804
1805/**
1806 * Removes a page record from our lookup tree
1807 *
1808 * @returns VBox status code
1809 * @param pVM The VM to operate on.
1810 * @param GCPtr Page address
1811 */
1812static int csamRemovePageRecord(PVM pVM, RTGCPTR GCPtr)
1813{
1814 PCSAMPAGEREC pPageRec;
1815
1816 Log(("csamRemovePageRecord %VGv\n", GCPtr));
1817 pPageRec = (PCSAMPAGEREC)RTAvlPVRemove(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
1818
1819 if (pPageRec)
1820 {
1821 STAM_COUNTER_INC(&pVM->csam.s.StatNrRemovedPages);
1822
1823#ifdef CSAM_MONITOR_CODE_PAGES
1824 if (pPageRec->page.fMonitorActive)
1825 {
1826 /* @todo -> this is expensive (cr3 reload)!!!
1827 * if this happens often, then reuse it instead!!!
1828 */
1829 Assert(!fInCSAMCodePageInvalidate);
1830 STAM_COUNTER_DEC(&pVM->csam.s.StatPageMonitor);
1831 PGMHandlerVirtualDeregister(pVM, GCPtr);
1832 }
1833 if (pPageRec->page.enmTag == CSAM_TAG_PATM)
1834 {
1835 /* Make sure the recompiler flushes its cache as this page is no longer monitored. */
1836 STAM_COUNTER_INC(&pVM->csam.s.StatPageRemoveREMFlush);
1837 CPUMSetChangedFlags(pVM, CPUM_CHANGED_GLOBAL_TLB_FLUSH);
1838 }
1839#endif
1840
1841#ifdef VBOX_WITH_STATISTICS
1842 switch (pPageRec->page.enmTag)
1843 {
1844 case CSAM_TAG_CSAM:
1845 STAM_COUNTER_DEC(&pVM->csam.s.StatPageCSAM);
1846 break;
1847 case CSAM_TAG_PATM:
1848 STAM_COUNTER_DEC(&pVM->csam.s.StatPagePATM);
1849 break;
1850 case CSAM_TAG_REM:
1851 STAM_COUNTER_DEC(&pVM->csam.s.StatPageREM);
1852 break;
1853 default:
1854 break; /* to shut up GCC */
1855 }
1856#endif
1857
1858 if (pPageRec->page.pBitmap) MMR3HeapFree(pPageRec->page.pBitmap);
1859 MMR3HeapFree(pPageRec);
1860 }
1861 else
1862 AssertFailed();
1863
1864 return VINF_SUCCESS;
1865}
1866
1867/**
1868 * Callback for delayed writes from non-EMT threads
1869 *
1870 * @param pVM VM Handle.
1871 * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1872 * @param cbBuf How much it's reading/writing.
1873 */
1874static DECLCALLBACK(void) CSAMDelayedWriteHandler(PVM pVM, RTGCPTR GCPtr, size_t cbBuf)
1875{
1876 int rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1877 AssertRC(rc);
1878}
1879
1880/**
1881 * #PF Handler callback for virtual access handler ranges.
1882 *
1883 * Important to realize that a physical page in a range can have aliases, and
1884 * for ALL and WRITE handlers these will also trigger.
1885 *
1886 * @returns VINF_SUCCESS if the handler have carried out the operation.
1887 * @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation.
1888 * @param pVM VM Handle.
1889 * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1890 * @param pvPtr The HC mapping of that address.
1891 * @param pvBuf What the guest is reading/writing.
1892 * @param cbBuf How much it's reading/writing.
1893 * @param enmAccessType The access type.
1894 * @param pvUser User argument.
1895 */
1896static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser)
1897{
1898 int rc;
1899
1900 Assert(enmAccessType == PGMACCESSTYPE_WRITE);
1901 Log(("CSAMCodePageWriteHandler: write to %VGv size=%d\n", GCPtr, cbBuf));
1902
1903 if (VM_IS_EMT(pVM))
1904 {
1905 rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1906 }
1907 else
1908 {
1909 /* Queue the write instead otherwise we'll get concurrency issues. */
1910 /** @note in theory not correct to let it write the data first before disabling a patch!
1911 * (if it writes the same data as the patch jump and we replace it with obsolete opcodes)
1912 */
1913 Log(("CSAMCodePageWriteHandler: delayed write!\n"));
1914 rc = VMR3ReqCallEx(pVM, NULL, 0, VMREQFLAGS_NO_WAIT | VMREQFLAGS_VOID,
1915 (PFNRT)CSAMDelayedWriteHandler, 3, pVM, GCPtr, cbBuf);
1916 }
1917 AssertRC(rc);
1918
1919 return VINF_PGM_HANDLER_DO_DEFAULT;
1920}
1921
1922/**
1923 * #PF Handler callback for invalidation of virtual access handler ranges.
1924 *
1925 * @param pVM VM Handle.
1926 * @param GCPtr The virtual address the guest has changed.
1927 */
1928static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr)
1929{
1930 fInCSAMCodePageInvalidate = true;
1931 LogFlow(("CSAMCodePageInvalidate %VGv\n", GCPtr));
1932 /** @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. */
1933 csamFlushPage(pVM, GCPtr, false /* don't remove page! */);
1934 fInCSAMCodePageInvalidate = false;
1935 return VINF_SUCCESS;
1936}
1937
1938/**
1939 * Check if the current instruction has already been checked before
1940 *
1941 * @returns VBox status code. (trap handled or not)
1942 * @param pVM The VM to operate on.
1943 * @param pInstr Instruction pointer
1944 * @param pPage CSAM patch structure pointer
1945 */
1946bool csamIsCodeScanned(PVM pVM, RTGCPTR pInstr, PCSAMPAGE *pPage)
1947{
1948 PCSAMPAGEREC pPageRec;
1949 uint32_t offset;
1950
1951 STAM_PROFILE_START(&pVM->csam.s.StatTimeCheckAddr, a);
1952
1953 offset = pInstr & PAGE_OFFSET_MASK;
1954 pInstr = pInstr & PAGE_BASE_GC_MASK;
1955
1956 Assert(pPage);
1957
1958 if (*pPage && (*pPage)->pPageGC == pInstr)
1959 {
1960 if ((*pPage)->pBitmap == NULL || ASMBitTest((*pPage)->pBitmap, offset))
1961 {
1962 STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
1963 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1964 return true;
1965 }
1966 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1967 return false;
1968 }
1969
1970 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstr);
1971 if (pPageRec)
1972 {
1973 if (pPage) *pPage= &pPageRec->page;
1974 if (pPageRec->page.pBitmap == NULL || ASMBitTest(pPageRec->page.pBitmap, offset))
1975 {
1976 STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
1977 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1978 return true;
1979 }
1980 }
1981 else
1982 {
1983 if (pPage) *pPage = NULL;
1984 }
1985 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
1986 return false;
1987}
1988
1989/**
1990 * Mark an instruction in a page as scanned/not scanned
1991 *
1992 * @param pVM The VM to operate on.
1993 * @param pPage Patch structure pointer
1994 * @param pInstr Instruction pointer
1995 * @param opsize Instruction size
1996 * @param fScanned Mark as scanned or not
1997 */
1998static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTGCPTR pInstr, uint32_t opsize, bool fScanned)
1999{
2000 LogFlow(("csamMarkCodeAsScanned %VGv opsize=%d\n", pInstr, opsize));
2001 CSAMMarkPage(pVM, pInstr, fScanned);
2002
2003 /** @todo should recreate empty bitmap if !fScanned */
2004 if (pPage->pBitmap == NULL)
2005 return;
2006
2007 if (fScanned)
2008 {
2009 // retn instructions can be scanned more than once
2010 if (ASMBitTest(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK) == 0)
2011 {
2012 pPage->uSize += opsize;
2013 STAM_COUNTER_ADD(&pVM->csam.s.StatNrInstr, 1);
2014 }
2015 if (pPage->uSize >= PAGE_SIZE)
2016 {
2017 Log(("Scanned full page (%VGv) -> free bitmap\n", pInstr & PAGE_BASE_GC_MASK));
2018 MMR3HeapFree(pPage->pBitmap);
2019 pPage->pBitmap = NULL;
2020 }
2021 else
2022 ASMBitSet(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2023 }
2024 else
2025 ASMBitClear(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2026}
2027
2028/**
2029 * Mark an instruction in a page as scanned/not scanned
2030 *
2031 * @returns VBox status code.
2032 * @param pVM The VM to operate on.
2033 * @param pInstr Instruction pointer
2034 * @param opsize Instruction size
2035 * @param fScanned Mark as scanned or not
2036 */
2037CSAMR3DECL(int) CSAMR3MarkCode(PVM pVM, RTGCPTR pInstr, uint32_t opsize, bool fScanned)
2038{
2039 PCSAMPAGE pPage = 0;
2040
2041 Assert(!fScanned); /* other case not implemented. */
2042 Assert(!PATMIsPatchGCAddr(pVM, pInstr));
2043
2044 if (csamIsCodeScanned(pVM, pInstr, &pPage) == false)
2045 {
2046 Assert(fScanned == true); /* other case should not be possible */
2047 return VINF_SUCCESS;
2048 }
2049
2050 Log(("CSAMR3MarkCode: %VGv size=%d fScanned=%d\n", pInstr, opsize, fScanned));
2051 csamMarkCode(pVM, pPage, pInstr, opsize, fScanned);
2052 return VINF_SUCCESS;
2053}
2054
2055
2056/**
2057 * Scan and analyse code
2058 *
2059 * @returns VBox status code.
2060 * @param pVM The VM to operate on.
2061 * @param Sel selector
2062 * @param pHiddenSel The hidden selector register.
2063 * @param pInstrGC Instruction pointer
2064 */
2065CSAMR3DECL(int) CSAMR3CheckCodeEx(PVM pVM, RTSEL Sel, CPUMSELREGHID *pHiddenSel, RTGCPTR pInstrGC)
2066{
2067 if (EMIsRawRing0Enabled(pVM) == false || PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2068 {
2069 // No use
2070 return VINF_SUCCESS;
2071 }
2072
2073 if (CSAMIsEnabled(pVM))
2074 {
2075 X86EFLAGS fakeflags;
2076
2077 /* we're not in v86 mode here */
2078 fakeflags.u32 = 0;
2079
2080 bool fCode32 = SELMIsSelector32Bit(pVM, fakeflags, Sel, pHiddenSel);
2081
2082 //assuming 32 bits code for now
2083 Assert(fCode32); NOREF(fCode32);
2084
2085 pInstrGC = SELMToFlat(pVM, fakeflags, Sel, pHiddenSel, pInstrGC);
2086
2087 return CSAMR3CheckCode(pVM, pInstrGC);
2088 }
2089 return VINF_SUCCESS;
2090}
2091
2092/**
2093 * Scan and analyse code
2094 *
2095 * @returns VBox status code.
2096 * @param pVM The VM to operate on.
2097 * @param pInstrGC Instruction pointer (0:32 virtual address)
2098 */
2099CSAMR3DECL(int) CSAMR3CheckCode(PVM pVM, RTGCPTR pInstrGC)
2100{
2101 int rc;
2102 PCSAMPAGE pPage = NULL;
2103
2104 if (EMIsRawRing0Enabled(pVM) == false || PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2105 {
2106 // No use
2107 return VINF_SUCCESS;
2108 }
2109
2110 if (CSAMIsEnabled(pVM))
2111 {
2112 // Cache record for PATMGCVirtToHCVirt
2113 CSAMP2GLOOKUPREC cacheRec = {0};
2114
2115 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2116 rc = csamAnalyseCallCodeStream(pVM, pInstrGC, pInstrGC, true /* 32 bits code */, CSAMR3AnalyseCallback, pPage, &cacheRec);
2117 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2118 if (rc != VINF_SUCCESS)
2119 {
2120 Log(("csamAnalyseCodeStream failed with %d\n", rc));
2121 return rc;
2122 }
2123 }
2124 return VINF_SUCCESS;
2125}
2126
2127/**
2128 * Flush dirty code pages
2129 *
2130 * @returns VBox status code.
2131 * @param pVM The VM to operate on.
2132 */
2133static int csamR3FlushDirtyPages(PVM pVM)
2134{
2135 STAM_PROFILE_START(&pVM->csam.s.StatFlushDirtyPages, a);
2136
2137 for (uint32_t i=0;i<pVM->csam.s.cDirtyPages;i++)
2138 {
2139 int rc;
2140 PCSAMPAGEREC pPageRec;
2141 RTGCPTR GCPtr = pVM->csam.s.pvDirtyBasePage[i];
2142
2143 GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2144
2145 /* Notify the recompiler that this page has been changed. */
2146 REMR3NotifyCodePageChanged(pVM, GCPtr);
2147
2148 /* Enable write protection again. (use the fault address as it might be an alias) */
2149 rc = PGMShwModifyPage(pVM, pVM->csam.s.pvDirtyFaultPage[i], 1, 0, ~(uint64_t)X86_PTE_RW);
2150 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
2151
2152 Log(("CSAMR3FlushDirtyPages: flush %VGv (modifypage rc=%Vrc)\n", pVM->csam.s.pvDirtyBasePage[i], rc));
2153
2154 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
2155 if (pPageRec && pPageRec->page.enmTag == CSAM_TAG_REM)
2156 {
2157 uint64_t fFlags;
2158
2159 rc = PGMGstGetPage(pVM, GCPtr, &fFlags, NULL);
2160 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
2161 if ( rc == VINF_SUCCESS
2162 && (fFlags & X86_PTE_US))
2163 {
2164 /* We don't care about user pages. */
2165 csamRemovePageRecord(pVM, GCPtr);
2166 STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
2167 }
2168 }
2169 }
2170 pVM->csam.s.cDirtyPages = 0;
2171 STAM_PROFILE_STOP(&pVM->csam.s.StatFlushDirtyPages, a);
2172 return VINF_SUCCESS;
2173}
2174
2175/**
2176 * Flush potential new code pages
2177 *
2178 * @returns VBox status code.
2179 * @param pVM The VM to operate on.
2180 */
2181static int csamR3FlushCodePages(PVM pVM)
2182{
2183 for (uint32_t i=0;i<pVM->csam.s.cPossibleCodePages;i++)
2184 {
2185 RTGCPTR GCPtr = pVM->csam.s.pvPossibleCodePage[i];
2186
2187 GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2188
2189 Log(("csamR3FlushCodePages: %VGv\n", GCPtr));
2190 PGMShwSetPage(pVM, GCPtr, 1, 0);
2191 /* Resync the page to make sure instruction fetch will fault */
2192 CSAMMarkPage(pVM, GCPtr, false);
2193 }
2194 pVM->csam.s.cPossibleCodePages = 0;
2195 return VINF_SUCCESS;
2196}
2197
2198/**
2199 * Perform any pending actions
2200 *
2201 * @returns VBox status code.
2202 * @param pVM The VM to operate on.
2203 */
2204CSAMR3DECL(int) CSAMR3DoPendingAction(PVM pVM)
2205{
2206 csamR3FlushDirtyPages(pVM);
2207 csamR3FlushCodePages(pVM);
2208
2209 VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
2210 return VINF_SUCCESS;
2211}
2212
2213/**
2214 * Analyse interrupt and trap gates
2215 *
2216 * @returns VBox status code.
2217 * @param pVM The VM to operate on.
2218 * @param iGate Start gate
2219 * @param cGates Number of gates to check
2220 */
2221CSAMR3DECL(int) CSAMR3CheckGates(PVM pVM, uint32_t iGate, uint32_t cGates)
2222{
2223 uint16_t cbIDT;
2224 RTGCPTR GCPtrIDT = CPUMGetGuestIDTR(pVM, &cbIDT);
2225 uint32_t iGateEnd;
2226 uint32_t maxGates;
2227 VBOXIDTE aIDT[256];
2228 PVBOXIDTE pGuestIdte;
2229 int rc;
2230
2231 if (EMIsRawRing0Enabled(pVM) == false)
2232 {
2233 /* Enabling interrupt gates only works when raw ring 0 is enabled. */
2234 //AssertFailed();
2235 return VINF_SUCCESS;
2236 }
2237
2238 /* We only check all gates once during a session */
2239 if ( !pVM->csam.s.fGatesChecked
2240 && cGates != 256)
2241 return VINF_SUCCESS; /* too early */
2242
2243 /* We only check all gates once during a session */
2244 if ( pVM->csam.s.fGatesChecked
2245 && cGates != 1)
2246 return VINF_SUCCESS; /* ignored */
2247
2248 Assert(cGates <= 256);
2249 if (!GCPtrIDT || cGates > 256)
2250 return VERR_INVALID_PARAMETER;
2251
2252 if (cGates != 1)
2253 {
2254 pVM->csam.s.fGatesChecked = true;
2255 for (unsigned i=0;i<RT_ELEMENTS(pVM->csam.s.pvCallInstruction);i++)
2256 {
2257 RTGCPTR pHandler = pVM->csam.s.pvCallInstruction[i];
2258 CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2259 PCSAMPAGE pPage = NULL;
2260
2261 Log(("CSAMCheckGates: checking previous call instruction %VGv\n", pHandler));
2262 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2263 rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2264 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2265 if (rc != VINF_SUCCESS)
2266 {
2267 Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2268 continue;
2269 }
2270 }
2271 }
2272
2273 /* Determine valid upper boundary. */
2274 maxGates = (cbIDT+1) / sizeof(VBOXIDTE);
2275 Assert(iGate < maxGates);
2276 if (iGate > maxGates)
2277 return VERR_INVALID_PARAMETER;
2278
2279 if (iGate + cGates > maxGates)
2280 cGates = maxGates - iGate;
2281
2282 GCPtrIDT = GCPtrIDT + iGate * sizeof(VBOXIDTE);
2283 iGateEnd = iGate + cGates;
2284
2285 STAM_PROFILE_START(&pVM->csam.s.StatCheckGates, a);
2286
2287 /*
2288 * Get IDT entries.
2289 */
2290 if (PAGE_ADDRESS(GCPtrIDT) == PAGE_ADDRESS(GCPtrIDT+cGates*sizeof(VBOXIDTE)))
2291 {
2292 /* Just convert the IDT address to a HC pointer. The whole IDT fits in one page. */
2293 rc = PGMPhysGCPtr2HCPtr(pVM, GCPtrIDT, (PRTHCPTR)&pGuestIdte);
2294 if (VBOX_FAILURE(rc))
2295 {
2296 AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2297 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2298 return rc;
2299 }
2300 }
2301 else
2302 {
2303 /* Slow method when it crosses a page boundary. */
2304 rc = PGMPhysReadGCPtr(pVM, aIDT, GCPtrIDT, cGates*sizeof(VBOXIDTE));
2305 if (VBOX_FAILURE(rc))
2306 {
2307 AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2308 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2309 return rc;
2310 }
2311 pGuestIdte = &aIDT[0];
2312 }
2313
2314 for (/*iGate*/; iGate<iGateEnd; iGate++, pGuestIdte++)
2315 {
2316 Assert(TRPMR3GetGuestTrapHandler(pVM, iGate) == TRPM_INVALID_HANDLER);
2317
2318 if ( pGuestIdte->Gen.u1Present
2319 && (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32 || pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_INT_32)
2320 && (pGuestIdte->Gen.u2DPL == 3 || pGuestIdte->Gen.u2DPL == 0)
2321 )
2322 {
2323 RTGCPTR pHandler;
2324 CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2325 PCSAMPAGE pPage = NULL;
2326 X86EFLAGS fakeflags;
2327 SELMSELINFO selInfo;
2328
2329 /* we're not in v86 mode here */
2330 fakeflags.u32 = 0;
2331
2332 pHandler = (pGuestIdte->Gen.u16OffsetHigh << 16) | pGuestIdte->Gen.u16OffsetLow;
2333 pHandler = SELMToFlat(pVM, fakeflags, pGuestIdte->Gen.u16SegSel, 0, pHandler);
2334
2335 rc = SELMR3GetSelectorInfo(pVM, pGuestIdte->Gen.u16SegSel, &selInfo);
2336 if ( VBOX_FAILURE(rc)
2337 || selInfo.GCPtrBase != 0
2338 || selInfo.cbLimit != ~0U
2339 )
2340 {
2341 /* Refuse to patch a handler whose idt cs selector isn't wide open. */
2342 Log(("CSAMCheckGates: check gate %d failed due to rc %Vrc GCPtrBase=%VGv limit=%x\n", iGate, rc, selInfo.GCPtrBase, selInfo.cbLimit));
2343 continue;
2344 }
2345
2346
2347 if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2348 {
2349 Log(("CSAMCheckGates: check trap gate %d at %04X:%08X (flat %VGv)\n", iGate, pGuestIdte->Gen.u16SegSel, (pGuestIdte->Gen.u16OffsetHigh << 16) | pGuestIdte->Gen.u16OffsetLow, pHandler));
2350 }
2351 else
2352 {
2353 Log(("CSAMCheckGates: check interrupt gate %d at %04X:%08X (flat %VGv)\n", iGate, pGuestIdte->Gen.u16SegSel, (pGuestIdte->Gen.u16OffsetHigh << 16) | pGuestIdte->Gen.u16OffsetLow, pHandler));
2354 }
2355
2356 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2357 rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2358 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2359 if (rc != VINF_SUCCESS)
2360 {
2361 Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2362 continue;
2363 }
2364 /* OpenBSD guest specific patch test. */
2365 if (iGate >= 0x20)
2366 {
2367 PCPUMCTX pCtx;
2368 DISCPUSTATE cpu;
2369 RTGCUINTPTR aOpenBsdPushCSOffset[3] = {0x03, /* OpenBSD 3.7 & 3.8 */
2370 0x2B, /* OpenBSD 4.0 installation ISO */
2371 0x2F}; /* OpenBSD 4.0 after install */
2372
2373 rc = CPUMQueryGuestCtxPtr(pVM, &pCtx);
2374 AssertRC(rc); /* can't fail */
2375
2376 for (unsigned i=0;i<ELEMENTS(aOpenBsdPushCSOffset);i++)
2377 {
2378 rc = CPUMR3DisasmInstrCPU(pVM, pCtx, pHandler - aOpenBsdPushCSOffset[i], &cpu, NULL);
2379 if ( rc == VINF_SUCCESS
2380 && cpu.pCurInstr->opcode == OP_PUSH
2381 && cpu.pCurInstr->param1 == OP_PARM_REG_CS)
2382 {
2383 rc = PATMR3InstallPatch(pVM, pHandler - aOpenBsdPushCSOffset[i], PATMFL_CODE32 | PATMFL_GUEST_SPECIFIC);
2384 if (VBOX_SUCCESS(rc))
2385 Log(("Installed OpenBSD interrupt handler prefix instruction (push cs) patch\n"));
2386 }
2387 }
2388 }
2389
2390 /* Trap gates and certain interrupt gates. */
2391 uint32_t fPatchFlags = PATMFL_CODE32 | PATMFL_IDTHANDLER;
2392
2393 if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2394 fPatchFlags |= PATMFL_TRAPHANDLER;
2395 else
2396 fPatchFlags |= PATMFL_INTHANDLER;
2397
2398 switch (iGate) {
2399 case 8:
2400 case 10:
2401 case 11:
2402 case 12:
2403 case 13:
2404 case 14:
2405 case 17:
2406 fPatchFlags |= PATMFL_TRAPHANDLER_WITH_ERRORCODE;
2407 break;
2408 default:
2409 /* No error code. */
2410 break;
2411 }
2412
2413 Log(("Installing %s gate handler for 0x%X at %VGv\n", (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32) ? "trap" : "intr", iGate, pHandler));
2414
2415 rc = PATMR3InstallPatch(pVM, pHandler, fPatchFlags);
2416 if (VBOX_SUCCESS(rc) || rc == VERR_PATM_ALREADY_PATCHED)
2417 {
2418 Log(("Gate handler 0x%X is SAFE!\n", iGate));
2419
2420 RTGCPTR pNewHandlerGC = PATMR3QueryPatchGCPtr(pVM, pHandler);
2421 if (pNewHandlerGC)
2422 {
2423 rc = TRPMR3SetGuestTrapHandler(pVM, iGate, pNewHandlerGC);
2424 if (VBOX_FAILURE(rc))
2425 Log(("TRPMR3SetGuestTrapHandler %d failed with %Vrc\n", iGate, rc));
2426 }
2427 }
2428 }
2429 } /* for */
2430 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2431 return VINF_SUCCESS;
2432}
2433
2434/**
2435 * Record previous call instruction addresses
2436 *
2437 * @returns VBox status code.
2438 * @param pVM The VM to operate on.
2439 * @param GCPtrCall Call address
2440 */
2441CSAMR3DECL(int) CSAMR3RecordCallAddress(PVM pVM, RTGCPTR GCPtrCall)
2442{
2443 for (unsigned i=0;i<RT_ELEMENTS(pVM->csam.s.pvCallInstruction);i++)
2444 {
2445 if (pVM->csam.s.pvCallInstruction[i] == GCPtrCall)
2446 return VINF_SUCCESS;
2447 }
2448
2449 Log(("CSAMR3RecordCallAddress %VGv\n", GCPtrCall));
2450
2451 pVM->csam.s.pvCallInstruction[pVM->csam.s.iCallInstruction++] = GCPtrCall;
2452 if (pVM->csam.s.iCallInstruction >= RT_ELEMENTS(pVM->csam.s.pvCallInstruction))
2453 pVM->csam.s.iCallInstruction = 0;
2454
2455 return VINF_SUCCESS;
2456}
2457
2458
2459/**
2460 * Query CSAM state (enabled/disabled)
2461 *
2462 * @returns 0 - disabled, 1 - enabled
2463 * @param pVM The VM to operate on.
2464 */
2465CSAMR3DECL(int) CSAMR3IsEnabled(PVM pVM)
2466{
2467 return pVM->fCSAMEnabled;
2468}
2469
2470#ifdef VBOX_WITH_DEBUGGER
2471/**
2472 * The '.csamoff' command.
2473 *
2474 * @returns VBox status.
2475 * @param pCmd Pointer to the command descriptor (as registered).
2476 * @param pCmdHlp Pointer to command helper functions.
2477 * @param pVM Pointer to the current VM (if any).
2478 * @param paArgs Pointer to (readonly) array of arguments.
2479 * @param cArgs Number of arguments in the array.
2480 */
2481static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2482{
2483 /*
2484 * Validate input.
2485 */
2486 if (!pVM)
2487 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2488
2489 CSAMDisableScanning(pVM);
2490 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning disabled\n");
2491}
2492
2493/**
2494 * The '.csamon' command.
2495 *
2496 * @returns VBox status.
2497 * @param pCmd Pointer to the command descriptor (as registered).
2498 * @param pCmdHlp Pointer to command helper functions.
2499 * @param pVM Pointer to the current VM (if any).
2500 * @param paArgs Pointer to (readonly) array of arguments.
2501 * @param cArgs Number of arguments in the array.
2502 */
2503static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2504{
2505 /*
2506 * Validate input.
2507 */
2508 if (!pVM)
2509 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2510
2511 CSAMEnableScanning(pVM);
2512 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning enabled\n");
2513}
2514#endif
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