VirtualBox

source: vbox/trunk/src/VBox/VMM/PATM/CSAM.cpp@ 9412

Last change on this file since 9412 was 9412, checked in by vboxsync, 17 years ago

use macros to access base, limit of a descriptor and offset of an IDT entry

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1/* $Id: CSAM.cpp 9412 2008-06-05 11:56:28Z vboxsync $ */
2/** @file
3 * CSAM - Guest OS Code Scanning and Analysis Manager
4 */
5
6/*
7 * Copyright (C) 2006-2007 Sun Microsystems, Inc.
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 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
18 * Clara, CA 95054 USA or visit http://www.sun.com if you need
19 * additional information or have any questions.
20 */
21
22/*******************************************************************************
23* Header Files *
24*******************************************************************************/
25#define LOG_GROUP LOG_GROUP_CSAM
26#include <VBox/cpum.h>
27#include <VBox/stam.h>
28#include <VBox/patm.h>
29#include <VBox/csam.h>
30#include <VBox/cpumdis.h>
31#include <VBox/pgm.h>
32#include <VBox/iom.h>
33#include <VBox/sup.h>
34#include <VBox/mm.h>
35#include <VBox/em.h>
36#include <VBox/rem.h>
37#include <VBox/selm.h>
38#include <VBox/trpm.h>
39#include <VBox/cfgm.h>
40#include <VBox/param.h>
41#include <iprt/avl.h>
42#include <iprt/asm.h>
43#include <iprt/thread.h>
44#include "CSAMInternal.h"
45#include <VBox/vm.h>
46#include <VBox/dbg.h>
47#include <VBox/err.h>
48#include <VBox/ssm.h>
49#include <VBox/log.h>
50#include <iprt/assert.h>
51#include <iprt/string.h>
52#include <VBox/dis.h>
53#include <VBox/disopcode.h>
54#include <stdlib.h>
55#include <stdio.h>
56
57
58/* Enabled by default */
59#define CSAM_ENABLE
60
61/* Enable to monitor code pages for self-modifying code. */
62#define CSAM_MONITOR_CODE_PAGES
63/* Enable to monitor all scanned pages
64#define CSAM_MONITOR_CSAM_CODE_PAGES */
65/* Enable to scan beyond ret instructions.
66#define CSAM_ANALYSE_BEYOND_RET */
67
68/*******************************************************************************
69* Internal Functions *
70*******************************************************************************/
71static DECLCALLBACK(int) csamr3Save(PVM pVM, PSSMHANDLE pSSM);
72static DECLCALLBACK(int) csamr3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version);
73static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser);
74static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr);
75
76bool csamIsCodeScanned(PVM pVM, RTRCPTR pInstr, PCSAMPAGE *pPage);
77int csamR3CheckPageRecord(PVM pVM, RTRCPTR pInstr);
78static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTRCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation = false);
79static int csamRemovePageRecord(PVM pVM, RTRCPTR GCPtr);
80static int csamReinit(PVM pVM);
81static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTRCPTR pInstr, uint32_t opsize, bool fScanned);
82static int csamAnalyseCodeStream(PVM pVM, RCPTRTYPE(uint8_t *) pInstrGC, RCPTRTYPE(uint8_t *) pCurInstrGC, bool fCode32,
83 PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec);
84
85/** @todo Temporary for debugging. */
86static bool fInCSAMCodePageInvalidate = false;
87
88/*******************************************************************************
89* Global Variables *
90*******************************************************************************/
91#ifdef VBOX_WITH_DEBUGGER
92static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult);
93static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult);
94
95/** Command descriptors. */
96static const DBGCCMD g_aCmds[] =
97{
98 /* pszCmd, cArgsMin, cArgsMax, paArgDesc, cArgDescs, pResultDesc, fFlags, pfnHandler pszSyntax, ....pszDescription */
99 { "csamon", 0, 0, NULL, 0, NULL, 0, csamr3CmdOn, "", "Enable CSAM code scanning." },
100 { "csamoff", 0, 0, NULL, 0, NULL, 0, csamr3CmdOff, "", "Disable CSAM code scanning." },
101};
102#endif
103
104
105/**
106 * Initializes the CSAM.
107 *
108 * @returns VBox status code.
109 * @param pVM The VM to operate on.
110 */
111CSAMR3DECL(int) CSAMR3Init(PVM pVM)
112{
113 int rc;
114
115 LogFlow(("CSAMR3Init\n"));
116
117 /* Allocate bitmap for the page directory. */
118 rc = MMR3HyperAllocOnceNoRel(pVM, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR), 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDBitmapHC);
119 AssertRCReturn(rc, rc);
120 rc = MMR3HyperAllocOnceNoRel(pVM, CSAM_PGDIRBMP_CHUNKS*sizeof(RTRCPTR), 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDGCBitmapHC);
121 AssertRCReturn(rc, rc);
122 pVM->csam.s.pPDBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDGCBitmapHC);
123 pVM->csam.s.pPDHCBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC);
124
125 rc = csamReinit(pVM);
126 AssertRCReturn(rc, rc);
127
128 /*
129 * Register save and load state notificators.
130 */
131 rc = SSMR3RegisterInternal(pVM, "CSAM", 0, CSAM_SSM_VERSION, sizeof(pVM->csam.s) + PAGE_SIZE*16,
132 NULL, csamr3Save, NULL,
133 NULL, csamr3Load, NULL);
134 AssertRCReturn(rc, rc);
135
136 STAM_REG(pVM, &pVM->csam.s.StatNrTraps, STAMTYPE_COUNTER, "/CSAM/PageTraps", STAMUNIT_OCCURENCES, "The number of CSAM page traps.");
137 STAM_REG(pVM, &pVM->csam.s.StatDangerousWrite, STAMTYPE_COUNTER, "/CSAM/DangerousWrites", STAMUNIT_OCCURENCES, "The number of dangerous writes that cause a context switch.");
138
139 STAM_REG(pVM, &pVM->csam.s.StatNrPageNPHC, STAMTYPE_COUNTER, "/CSAM/HC/PageNotPresent", STAMUNIT_OCCURENCES, "The number of CSAM pages marked not present.");
140 STAM_REG(pVM, &pVM->csam.s.StatNrPageNPGC, STAMTYPE_COUNTER, "/CSAM/GC/PageNotPresent", STAMUNIT_OCCURENCES, "The number of CSAM pages marked not present.");
141 STAM_REG(pVM, &pVM->csam.s.StatNrPages, STAMTYPE_COUNTER, "/CSAM/PageRec/AddedRW", STAMUNIT_OCCURENCES, "The number of CSAM page records (RW monitoring).");
142 STAM_REG(pVM, &pVM->csam.s.StatNrPagesInv, STAMTYPE_COUNTER, "/CSAM/PageRec/AddedRWI", STAMUNIT_OCCURENCES, "The number of CSAM page records (RW & invalidation monitoring).");
143 STAM_REG(pVM, &pVM->csam.s.StatNrRemovedPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Removed", STAMUNIT_OCCURENCES, "The number of removed CSAM page records.");
144 STAM_REG(pVM, &pVM->csam.s.StatPageRemoveREMFlush,STAMTYPE_COUNTER, "/CSAM/PageRec/Removed/REMFlush", STAMUNIT_OCCURENCES, "The number of removed CSAM page records that caused a REM flush.");
145
146 STAM_REG(pVM, &pVM->csam.s.StatNrPatchPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Patch", STAMUNIT_OCCURENCES, "The number of CSAM patch page records.");
147 STAM_REG(pVM, &pVM->csam.s.StatNrUserPages, STAMTYPE_COUNTER, "/CSAM/PageRec/Ignore/User", STAMUNIT_OCCURENCES, "The number of CSAM user page records (ignored).");
148 STAM_REG(pVM, &pVM->csam.s.StatPagePATM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/PATM", STAMUNIT_OCCURENCES, "The number of PATM page records.");
149 STAM_REG(pVM, &pVM->csam.s.StatPageCSAM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/CSAM", STAMUNIT_OCCURENCES, "The number of CSAM page records.");
150 STAM_REG(pVM, &pVM->csam.s.StatPageREM, STAMTYPE_COUNTER, "/CSAM/PageRec/Type/REM", STAMUNIT_OCCURENCES, "The number of REM page records.");
151 STAM_REG(pVM, &pVM->csam.s.StatPageMonitor, STAMTYPE_COUNTER, "/CSAM/PageRec/Monitored", STAMUNIT_OCCURENCES, "The number of monitored pages.");
152
153 STAM_REG(pVM, &pVM->csam.s.StatCodePageModified, STAMTYPE_COUNTER, "/CSAM/Monitor/DirtyPage", STAMUNIT_OCCURENCES, "The number of code page modifications.");
154
155 STAM_REG(pVM, &pVM->csam.s.StatNrFlushes, STAMTYPE_COUNTER, "/CSAM/PageFlushes", STAMUNIT_OCCURENCES, "The number of CSAM page flushes.");
156 STAM_REG(pVM, &pVM->csam.s.StatNrFlushesSkipped, STAMTYPE_COUNTER, "/CSAM/PageFlushesSkipped", STAMUNIT_OCCURENCES, "The number of CSAM page flushes that were skipped.");
157 STAM_REG(pVM, &pVM->csam.s.StatNrKnownPagesHC, STAMTYPE_COUNTER, "/CSAM/HC/KnownPageRecords", STAMUNIT_OCCURENCES, "The number of known CSAM page records.");
158 STAM_REG(pVM, &pVM->csam.s.StatNrKnownPagesGC, STAMTYPE_COUNTER, "/CSAM/GC/KnownPageRecords", STAMUNIT_OCCURENCES, "The number of known CSAM page records.");
159 STAM_REG(pVM, &pVM->csam.s.StatNrInstr, STAMTYPE_COUNTER, "/CSAM/ScannedInstr", STAMUNIT_OCCURENCES, "The number of scanned instructions.");
160 STAM_REG(pVM, &pVM->csam.s.StatNrBytesRead, STAMTYPE_COUNTER, "/CSAM/BytesRead", STAMUNIT_OCCURENCES, "The number of bytes read for scanning.");
161 STAM_REG(pVM, &pVM->csam.s.StatNrOpcodeRead, STAMTYPE_COUNTER, "/CSAM/OpcodeBytesRead", STAMUNIT_OCCURENCES, "The number of opcode bytes read by the recompiler.");
162
163 STAM_REG(pVM, &pVM->csam.s.StatBitmapAlloc, STAMTYPE_COUNTER, "/CSAM/Alloc/PageBitmap", STAMUNIT_OCCURENCES, "The number of page bitmap allocations.");
164
165 STAM_REG(pVM, &pVM->csam.s.StatInstrCacheHit, STAMTYPE_COUNTER, "/CSAM/Cache/Hit", STAMUNIT_OCCURENCES, "The number of dangerous instruction cache hits.");
166 STAM_REG(pVM, &pVM->csam.s.StatInstrCacheMiss, STAMTYPE_COUNTER, "/CSAM/Cache/Miss", STAMUNIT_OCCURENCES, "The number of dangerous instruction cache misses.");
167
168 STAM_REG(pVM, &pVM->csam.s.StatScanNextFunction, STAMTYPE_COUNTER, "/CSAM/Function/Scan/Success", STAMUNIT_OCCURENCES, "The number of found functions beyond the ret border.");
169 STAM_REG(pVM, &pVM->csam.s.StatScanNextFunctionFailed, STAMTYPE_COUNTER, "/CSAM/Function/Scan/Failed", STAMUNIT_OCCURENCES, "The number of refused functions beyond the ret border.");
170
171 STAM_REG(pVM, &pVM->csam.s.StatTime, STAMTYPE_PROFILE, "/PROF/CSAM/Scan", STAMUNIT_TICKS_PER_CALL, "Scanning overhead.");
172 STAM_REG(pVM, &pVM->csam.s.StatTimeCheckAddr, STAMTYPE_PROFILE, "/PROF/CSAM/CheckAddr", STAMUNIT_TICKS_PER_CALL, "Address check overhead.");
173 STAM_REG(pVM, &pVM->csam.s.StatTimeAddrConv, STAMTYPE_PROFILE, "/PROF/CSAM/AddrConv", STAMUNIT_TICKS_PER_CALL, "Address conversion overhead.");
174 STAM_REG(pVM, &pVM->csam.s.StatTimeFlushPage, STAMTYPE_PROFILE, "/PROF/CSAM/FlushPage", STAMUNIT_TICKS_PER_CALL, "Page flushing overhead.");
175 STAM_REG(pVM, &pVM->csam.s.StatTimeDisasm, STAMTYPE_PROFILE, "/PROF/CSAM/Disasm", STAMUNIT_TICKS_PER_CALL, "Disassembly overhead.");
176 STAM_REG(pVM, &pVM->csam.s.StatFlushDirtyPages, STAMTYPE_PROFILE, "/PROF/CSAM/FlushDirtyPage", STAMUNIT_TICKS_PER_CALL, "Dirty page flushing overhead.");
177 STAM_REG(pVM, &pVM->csam.s.StatCheckGates, STAMTYPE_PROFILE, "/PROF/CSAM/CheckGates", STAMUNIT_TICKS_PER_CALL, "CSAMR3CheckGates overhead.");
178
179 /*
180 * Check CFGM option and enable/disable CSAM.
181 */
182 bool fEnabled;
183 rc = CFGMR3QueryBool(CFGMR3GetRoot(pVM), "CSAMEnabled", &fEnabled);
184 if (VBOX_FAILURE(rc))
185#ifdef CSAM_ENABLE
186 fEnabled = true;
187#else
188 fEnabled = false;
189#endif
190 if (fEnabled)
191 CSAMEnableScanning(pVM);
192
193#ifdef VBOX_WITH_DEBUGGER
194 /*
195 * Debugger commands.
196 */
197 static bool fRegisteredCmds = false;
198 if (!fRegisteredCmds)
199 {
200 int rc = DBGCRegisterCommands(&g_aCmds[0], ELEMENTS(g_aCmds));
201 if (VBOX_SUCCESS(rc))
202 fRegisteredCmds = true;
203 }
204#endif
205
206 return VINF_SUCCESS;
207}
208
209/**
210 * (Re)initializes CSAM
211 *
212 * @param pVM The VM.
213 */
214static int csamReinit(PVM pVM)
215{
216 /*
217 * Assert alignment and sizes.
218 */
219 AssertRelease(!(RT_OFFSETOF(VM, csam.s) & 31));
220 AssertRelease(sizeof(pVM->csam.s) <= sizeof(pVM->csam.padding));
221
222 /*
223 * Setup any fixed pointers and offsets.
224 */
225 pVM->csam.s.offVM = RT_OFFSETOF(VM, patm);
226
227 pVM->csam.s.fGatesChecked = false;
228 pVM->csam.s.fScanningStarted = false;
229
230 VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
231 pVM->csam.s.cDirtyPages = 0;
232 /* not necessary */
233 memset(pVM->csam.s.pvDirtyBasePage, 0, sizeof(pVM->csam.s.pvDirtyBasePage));
234 memset(pVM->csam.s.pvDirtyFaultPage, 0, sizeof(pVM->csam.s.pvDirtyFaultPage));
235
236 memset(&pVM->csam.s.aDangerousInstr, 0, sizeof(pVM->csam.s.aDangerousInstr));
237 pVM->csam.s.cDangerousInstr = 0;
238 pVM->csam.s.iDangerousInstr = 0;
239
240 memset(pVM->csam.s.pvCallInstruction, 0, sizeof(pVM->csam.s.pvCallInstruction));
241 pVM->csam.s.iCallInstruction = 0;
242
243 /** @note never mess with the pgdir bitmap here! */
244 return VINF_SUCCESS;
245}
246
247/**
248 * Applies relocations to data and code managed by this
249 * component. This function will be called at init and
250 * whenever the VMM need to relocate itself inside the GC.
251 *
252 * The csam will update the addresses used by the switcher.
253 *
254 * @param pVM The VM.
255 * @param offDelta Relocation delta.
256 */
257CSAMR3DECL(void) CSAMR3Relocate(PVM pVM, RTGCINTPTR offDelta)
258{
259 if (offDelta)
260 {
261 /* Adjust pgdir and page bitmap pointers. */
262 pVM->csam.s.pPDBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDGCBitmapHC);
263 pVM->csam.s.pPDHCBitmapGC = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC);
264
265 for(int i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
266 {
267 if (pVM->csam.s.pPDGCBitmapHC[i])
268 {
269 pVM->csam.s.pPDGCBitmapHC[i] += offDelta;
270 }
271 }
272 }
273 return;
274}
275
276/**
277 * Terminates the csam.
278 *
279 * Termination means cleaning up and freeing all resources,
280 * the VM it self is at this point powered off or suspended.
281 *
282 * @returns VBox status code.
283 * @param pVM The VM to operate on.
284 */
285CSAMR3DECL(int) CSAMR3Term(PVM pVM)
286{
287 int rc;
288
289 rc = CSAMR3Reset(pVM);
290 AssertRC(rc);
291
292 /* @todo triggers assertion in MMHyperFree */
293#if 0
294 for(int i=0;i<CSAM_PAGEBMP_CHUNKS;i++)
295 {
296 if (pVM->csam.s.pPDBitmapHC[i])
297 MMHyperFree(pVM, pVM->csam.s.pPDBitmapHC[i]);
298 }
299#endif
300
301 return VINF_SUCCESS;
302}
303
304/**
305 * CSAM reset callback.
306 *
307 * @returns VBox status code.
308 * @param pVM The VM which is reset.
309 */
310CSAMR3DECL(int) CSAMR3Reset(PVM pVM)
311{
312 /* Clear page bitmaps. */
313 for(int i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
314 {
315 if (pVM->csam.s.pPDBitmapHC[i])
316 {
317 Assert((CSAM_PAGE_BITMAP_SIZE& 3) == 0);
318 ASMMemZero32(pVM->csam.s.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
319 }
320 }
321
322 /* Remove all CSAM page records. */
323 while(true)
324 {
325 PCSAMPAGEREC pPageRec = (PCSAMPAGEREC)RTAvlPVGetBestFit(&pVM->csam.s.pPageTree, 0, true);
326 if (pPageRec)
327 {
328 csamRemovePageRecord(pVM, pPageRec->page.pPageGC);
329 }
330 else
331 break;
332 }
333 Assert(!pVM->csam.s.pPageTree);
334
335 csamReinit(pVM);
336
337 return VINF_SUCCESS;
338}
339
340#define CSAM_SUBTRACT_PTR(a, b) *(uintptr_t *)&(a) = (uintptr_t)(a) - (uintptr_t)(b)
341#define CSAM_ADD_PTR(a, b) *(uintptr_t *)&(a) = (uintptr_t)(a) + (uintptr_t)(b)
342
343
344/**
345 * Callback function for RTAvlPVDoWithAll
346 *
347 * Counts the number of records in the tree
348 *
349 * @returns VBox status code.
350 * @param pNode Current node
351 * @param pcPatches Pointer to patch counter
352 */
353static DECLCALLBACK(int) CountRecord(PAVLPVNODECORE pNode, void *pcPatches)
354{
355 *(uint32_t *)pcPatches = *(uint32_t *)pcPatches + 1;
356 return VINF_SUCCESS;
357}
358
359/**
360 * Callback function for RTAvlPVDoWithAll
361 *
362 * Saves the state of the page record
363 *
364 * @returns VBox status code.
365 * @param pNode Current node
366 * @param pVM1 VM Handle
367 */
368static DECLCALLBACK(int) SavePageState(PAVLPVNODECORE pNode, void *pVM1)
369{
370 PVM pVM = (PVM)pVM1;
371 PCSAMPAGEREC pPage = (PCSAMPAGEREC)pNode;
372 CSAMPAGEREC page = *pPage;
373 PSSMHANDLE pSSM = pVM->csam.s.savedstate.pSSM;
374 int rc;
375
376 /* Save the page record itself */
377 rc = SSMR3PutMem(pSSM, &page, sizeof(page));
378 AssertRCReturn(rc, rc);
379
380 if (page.page.pBitmap)
381 {
382 rc = SSMR3PutMem(pSSM, page.page.pBitmap, CSAM_PAGE_BITMAP_SIZE);
383 AssertRCReturn(rc, rc);
384 }
385
386 return VINF_SUCCESS;
387}
388
389/**
390 * Execute state save operation.
391 *
392 * @returns VBox status code.
393 * @param pVM VM Handle.
394 * @param pSSM SSM operation handle.
395 */
396static DECLCALLBACK(int) csamr3Save(PVM pVM, PSSMHANDLE pSSM)
397{
398 CSAM csamInfo = pVM->csam.s;
399 int rc;
400
401 /*
402 * Count the number of page records in the tree (feeling lazy)
403 */
404 csamInfo.savedstate.cPageRecords = 0;
405 RTAvlPVDoWithAll(&pVM->csam.s.pPageTree, true, CountRecord, &csamInfo.savedstate.cPageRecords);
406
407 /*
408 * Save CSAM structure
409 */
410 pVM->csam.s.savedstate.pSSM = pSSM;
411 rc = SSMR3PutMem(pSSM, &csamInfo, sizeof(csamInfo));
412 AssertRCReturn(rc, rc);
413
414 /* Save pgdir bitmap */
415 rc = SSMR3PutMem(pSSM, csamInfo.pPDBitmapHC, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR));
416 AssertRCReturn(rc, rc);
417
418 for (unsigned i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
419 {
420 if(csamInfo.pPDBitmapHC[i])
421 {
422 /* Save the page bitmap. */
423 rc = SSMR3PutMem(pSSM, csamInfo.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
424 AssertRCReturn(rc, rc);
425 }
426 }
427
428 /*
429 * Save page records
430 */
431 rc = RTAvlPVDoWithAll(&pVM->csam.s.pPageTree, true, SavePageState, pVM);
432 AssertRCReturn(rc, rc);
433
434 /** @note we don't restore aDangerousInstr; it will be recreated automatically. */
435 return VINF_SUCCESS;
436}
437
438/**
439 * Execute state load operation.
440 *
441 * @returns VBox status code.
442 * @param pVM VM Handle.
443 * @param pSSM SSM operation handle.
444 * @param u32Version Data layout version.
445 */
446static DECLCALLBACK(int) csamr3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version)
447{
448 int rc;
449 CSAM csamInfo;
450
451 if (u32Version != CSAM_SSM_VERSION)
452 return VERR_SSM_UNSUPPORTED_DATA_UNIT_VERSION;
453
454 pVM->csam.s.savedstate.pSSM = pSSM;
455
456 /*
457 * Restore CSAM structure
458 */
459 rc = SSMR3GetMem(pSSM, &csamInfo, sizeof(csamInfo));
460 AssertRCReturn(rc, rc);
461
462 pVM->csam.s.fGatesChecked = csamInfo.fGatesChecked;
463 pVM->csam.s.fScanningStarted = csamInfo.fScanningStarted;
464
465 /* Restore dirty code page info. */
466 pVM->csam.s.cDirtyPages = csamInfo.cDirtyPages;
467 memcpy(pVM->csam.s.pvDirtyBasePage, csamInfo.pvDirtyBasePage, sizeof(pVM->csam.s.pvDirtyBasePage));
468 memcpy(pVM->csam.s.pvDirtyFaultPage, csamInfo.pvDirtyFaultPage, sizeof(pVM->csam.s.pvDirtyFaultPage));
469
470 /* Restore possible code page */
471 pVM->csam.s.cPossibleCodePages = csamInfo.cPossibleCodePages;
472 memcpy(pVM->csam.s.pvPossibleCodePage, csamInfo.pvPossibleCodePage, sizeof(pVM->csam.s.pvPossibleCodePage));
473
474 /* Restore pgdir bitmap (we'll change the pointers next). */
475 rc = SSMR3GetMem(pSSM, pVM->csam.s.pPDBitmapHC, CSAM_PGDIRBMP_CHUNKS*sizeof(RTHCPTR));
476 AssertRCReturn(rc, rc);
477
478 /*
479 * Restore page bitmaps
480 */
481 for (unsigned i=0;i<CSAM_PGDIRBMP_CHUNKS;i++)
482 {
483 if(pVM->csam.s.pPDBitmapHC[i])
484 {
485 rc = MMHyperAlloc(pVM, CSAM_PAGE_BITMAP_SIZE, 0, MM_TAG_CSAM, (void **)&pVM->csam.s.pPDBitmapHC[i]);
486 if (VBOX_FAILURE(rc))
487 {
488 Log(("MMR3HyperAlloc failed with %d\n", rc));
489 return rc;
490 }
491 /* Convert to GC pointer. */
492 pVM->csam.s.pPDGCBitmapHC[i] = MMHyperHC2GC(pVM, pVM->csam.s.pPDBitmapHC[i]);
493 Assert(pVM->csam.s.pPDGCBitmapHC[i]);
494
495 /* Restore the bitmap. */
496 rc = SSMR3GetMem(pSSM, pVM->csam.s.pPDBitmapHC[i], CSAM_PAGE_BITMAP_SIZE);
497 AssertRCReturn(rc, rc);
498 }
499 else
500 {
501 Assert(!pVM->csam.s.pPDGCBitmapHC[i]);
502 pVM->csam.s.pPDGCBitmapHC[i] = 0;
503 }
504 }
505
506 /*
507 * Restore page records
508 */
509 for (uint32_t i=0;i<csamInfo.savedstate.cPageRecords + csamInfo.savedstate.cPatchPageRecords;i++)
510 {
511 CSAMPAGEREC page;
512 PCSAMPAGE pPage;
513
514 rc = SSMR3GetMem(pSSM, &page, sizeof(page));
515 AssertRCReturn(rc, rc);
516
517 /*
518 * Recreate the page record
519 */
520 pPage = csamCreatePageRecord(pVM, page.page.pPageGC, page.page.enmTag, page.page.fCode32, page.page.fMonitorInvalidation);
521 AssertReturn(pPage, VERR_NO_MEMORY);
522
523 pPage->GCPhys = page.page.GCPhys;
524 pPage->fFlags = page.page.fFlags;
525 pPage->u64Hash = page.page.u64Hash;
526
527 if (page.page.pBitmap)
528 {
529 rc = SSMR3GetMem(pSSM, pPage->pBitmap, CSAM_PAGE_BITMAP_SIZE);
530 AssertRCReturn(rc, rc);
531 }
532 else
533 {
534 MMR3HeapFree(pPage->pBitmap);
535 pPage->pBitmap = 0;
536 }
537 }
538
539 /** @note we don't restore aDangerousInstr; it will be recreated automatically. */
540 memset(&pVM->csam.s.aDangerousInstr, 0, sizeof(pVM->csam.s.aDangerousInstr));
541 pVM->csam.s.cDangerousInstr = 0;
542 pVM->csam.s.iDangerousInstr = 0;
543 return VINF_SUCCESS;
544}
545
546/**
547 * Convert guest context address to host context pointer
548 *
549 * @returns VBox status code.
550 * @param pVM The VM to operate on.
551 * @param pCacheRec Address conversion cache record
552 * @param pGCPtr Guest context pointer
553 *
554 * @returns Host context pointer or NULL in case of an error
555 *
556 */
557static R3PTRTYPE(void *) CSAMGCVirtToHCVirt(PVM pVM, PCSAMP2GLOOKUPREC pCacheRec, RCPTRTYPE(uint8_t *) pGCPtr)
558{
559 int rc;
560 R3PTRTYPE(void *) pHCPtr;
561
562 STAM_PROFILE_START(&pVM->csam.s.StatTimeAddrConv, a);
563
564 pHCPtr = PATMR3GCPtrToHCPtr(pVM, pGCPtr);
565 if (pHCPtr) return pHCPtr;
566
567 if (pCacheRec->pPageLocStartHC)
568 {
569 uint32_t offset = pGCPtr & PAGE_OFFSET_MASK;
570 if (pCacheRec->pGuestLoc == (pGCPtr & PAGE_BASE_GC_MASK))
571 {
572 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
573 return pCacheRec->pPageLocStartHC + offset;
574 }
575 }
576
577 rc = PGMPhysGCPtr2HCPtr(pVM, pGCPtr, &pHCPtr);
578 if (rc != VINF_SUCCESS)
579 {
580//// AssertMsgRC(rc, ("MMR3PhysGCVirt2HCVirtEx failed for %VRv\n", pGCPtr));
581 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
582 return NULL;
583 }
584////invalid? Assert(sizeof(R3PTRTYPE(uint8_t*)) == sizeof(uint32_t));
585
586 pCacheRec->pPageLocStartHC = (R3PTRTYPE(uint8_t*))((RTHCUINTPTR)pHCPtr & PAGE_BASE_HC_MASK);
587 pCacheRec->pGuestLoc = pGCPtr & PAGE_BASE_GC_MASK;
588 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeAddrConv, a);
589 return pHCPtr;
590}
591
592/**
593 * Read callback for disassembly function; supports reading bytes that cross a page boundary
594 *
595 * @returns VBox status code.
596 * @param pSrc GC source pointer
597 * @param pDest HC destination pointer
598 * @param size Number of bytes to read
599 * @param dwUserdata Callback specific user data (pCpu)
600 *
601 */
602static DECLCALLBACK(int) CSAMR3ReadBytes(RTUINTPTR pSrc, uint8_t *pDest, unsigned size, void *pvUserdata)
603{
604 DISCPUSTATE *pCpu = (DISCPUSTATE *)pvUserdata;
605 PVM pVM = (PVM)pCpu->apvUserData[0];
606 RTHCUINTPTR pInstrHC = (RTHCUINTPTR)pCpu->apvUserData[1];
607 RTGCUINTPTR32 pInstrGC = (uintptr_t)pCpu->apvUserData[2];
608 int orgsize = size;
609
610 /* We are not interested in patched instructions, so read the original opcode bytes. */
611 /** @note single instruction patches (int3) are checked in CSAMR3AnalyseCallback */
612 for (int i=0;i<orgsize;i++)
613 {
614 int rc = PATMR3QueryOpcode(pVM, (RTRCPTR)pSrc, pDest);
615 if (VBOX_SUCCESS(rc))
616 {
617 pSrc++;
618 pDest++;
619 size--;
620 }
621 else
622 break;
623 }
624 if (size == 0)
625 return VINF_SUCCESS;
626
627 if (PAGE_ADDRESS(pInstrGC) != PAGE_ADDRESS(pSrc + size - 1) && !PATMIsPatchGCAddr(pVM, pSrc))
628 {
629 return PGMPhysReadGCPtr(pVM, pDest, pSrc, size);
630 }
631 else
632 {
633 Assert(pInstrHC);
634
635 /* pInstrHC is the base address; adjust according to the GC pointer. */
636 pInstrHC = pInstrHC + (pSrc - pInstrGC);
637
638 memcpy(pDest, (void *)pInstrHC, size);
639 }
640
641 return VINF_SUCCESS;
642}
643
644inline int CSAMR3DISInstr(PVM pVM, DISCPUSTATE *pCpu, RTRCPTR InstrGC, uint8_t *InstrHC, uint32_t *pOpsize, char *pszOutput)
645{
646 (pCpu)->pfnReadBytes = CSAMR3ReadBytes;
647 (pCpu)->apvUserData[0] = pVM;
648 (pCpu)->apvUserData[1] = InstrHC;
649 (pCpu)->apvUserData[2] = (void *)InstrGC; Assert(sizeof(InstrGC) <= sizeof(pCpu->apvUserData[0]));
650#ifdef DEBUG
651 return DISInstrEx(pCpu, InstrGC, 0, pOpsize, pszOutput, OPTYPE_ALL);
652#else
653 /* We are interested in everything except harmless stuff */
654 return DISInstrEx(pCpu, InstrGC, 0, pOpsize, pszOutput, ~(OPTYPE_INVALID | OPTYPE_HARMLESS | OPTYPE_RRM_MASK));
655#endif
656}
657
658/**
659 * Analyses the instructions following the cli for compliance with our heuristics for cli
660 *
661 * @returns VBox status code.
662 * @param pVM The VM to operate on.
663 * @param pCpu CPU disassembly state
664 * @param pInstrGC Guest context pointer to privileged instruction
665 * @param pCurInstrGC Guest context pointer to the current instruction
666 * @param pCacheRec GC to HC cache record
667 * @param pUserData User pointer (callback specific)
668 *
669 */
670static int CSAMR3AnalyseCallback(PVM pVM, DISCPUSTATE *pCpu, RCPTRTYPE(uint8_t *) pInstrGC, RCPTRTYPE(uint8_t *) pCurInstrGC,
671 PCSAMP2GLOOKUPREC pCacheRec, void *pUserData)
672{
673 PCSAMPAGE pPage = (PCSAMPAGE)pUserData;
674 int rc;
675
676 switch(pCpu->pCurInstr->opcode)
677 {
678 case OP_INT:
679 Assert(pCpu->param1.flags & USE_IMMEDIATE8);
680 if (pCpu->param1.parval == 3)
681 {
682 //two byte int 3
683 return VINF_SUCCESS;
684 }
685 break;
686
687 case OP_ILLUD2:
688 /* This appears to be some kind of kernel panic in Linux 2.4; no point to continue. */
689 case OP_RETN:
690 case OP_INT3:
691 case OP_INVALID:
692#if 1
693 /* removing breaks win2k guests? */
694 case OP_IRET:
695#endif
696 return VINF_SUCCESS;
697 }
698
699 // Check for exit points
700 switch (pCpu->pCurInstr->opcode)
701 {
702 /* It's not a good idea to patch pushf instructions:
703 * - increases the chance of conflicts (code jumping to the next instruction)
704 * - better to patch the cli
705 * - code that branches before the cli will likely hit an int 3
706 * - in general doesn't offer any benefits as we don't allow nested patch blocks (IF is always 1)
707 */
708 case OP_PUSHF:
709 case OP_POPF:
710 break;
711
712 case OP_CLI:
713 {
714 uint32_t cbInstr = 0;
715 uint32_t opsize = pCpu->opsize;
716
717 PATMR3AddHint(pVM, pCurInstrGC, (pPage->fCode32) ? PATMFL_CODE32 : 0);
718
719 /* Make sure the instructions that follow the cli have not been encountered before. */
720 while (true)
721 {
722 DISCPUSTATE cpu;
723 uint8_t *pCurInstrHC = 0;
724
725 if (cbInstr + opsize >= SIZEOF_NEARJUMP32)
726 break;
727
728 if (csamIsCodeScanned(pVM, pCurInstrGC + opsize, &pPage) == true)
729 {
730 /* We've scanned the next instruction(s) already. This means we've followed a branch that ended up there before -> dangerous!! */
731 PATMR3DetectConflict(pVM, pCurInstrGC, pCurInstrGC + opsize);
732 break;
733 }
734 pCurInstrGC += opsize;
735 cbInstr += opsize;
736
737 pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
738 if (pCurInstrHC == NULL)
739 {
740 Log(("CSAMGCVirtToHCVirt failed for %VRv\n", pCurInstrGC));
741 break;
742 }
743 Assert(VALID_PTR(pCurInstrHC));
744
745 cpu.mode = (pPage->fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
746 rc = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
747 Assert(VBOX_SUCCESS(rc));
748 if (VBOX_FAILURE(rc))
749 break;
750 }
751 break;
752 }
753
754 case OP_PUSH:
755 if (pCpu->pCurInstr->param1 != OP_PARM_REG_CS)
756 break;
757
758 /* no break */
759 case OP_STR:
760 case OP_LSL:
761 case OP_LAR:
762 case OP_SGDT:
763 case OP_SLDT:
764 case OP_SIDT:
765 case OP_SMSW:
766 case OP_VERW:
767 case OP_VERR:
768 case OP_CPUID:
769 case OP_IRET:
770#ifdef DEBUG
771 switch(pCpu->pCurInstr->opcode)
772 {
773 case OP_STR:
774 Log(("Privileged instruction at %VRv: str!!\n", pCurInstrGC));
775 break;
776 case OP_LSL:
777 Log(("Privileged instruction at %VRv: lsl!!\n", pCurInstrGC));
778 break;
779 case OP_LAR:
780 Log(("Privileged instruction at %VRv: lar!!\n", pCurInstrGC));
781 break;
782 case OP_SGDT:
783 Log(("Privileged instruction at %VRv: sgdt!!\n", pCurInstrGC));
784 break;
785 case OP_SLDT:
786 Log(("Privileged instruction at %VRv: sldt!!\n", pCurInstrGC));
787 break;
788 case OP_SIDT:
789 Log(("Privileged instruction at %VRv: sidt!!\n", pCurInstrGC));
790 break;
791 case OP_SMSW:
792 Log(("Privileged instruction at %VRv: smsw!!\n", pCurInstrGC));
793 break;
794 case OP_VERW:
795 Log(("Privileged instruction at %VRv: verw!!\n", pCurInstrGC));
796 break;
797 case OP_VERR:
798 Log(("Privileged instruction at %VRv: verr!!\n", pCurInstrGC));
799 break;
800 case OP_CPUID:
801 Log(("Privileged instruction at %VRv: cpuid!!\n", pCurInstrGC));
802 break;
803 case OP_PUSH:
804 Log(("Privileged instruction at %VRv: push cs!!\n", pCurInstrGC));
805 break;
806 case OP_IRET:
807 Log(("Privileged instruction at %VRv: iret!!\n", pCurInstrGC));
808 break;
809 }
810#endif
811
812 if (PATMR3HasBeenPatched(pVM, pCurInstrGC) == false)
813 {
814 rc = PATMR3InstallPatch(pVM, pCurInstrGC, (pPage->fCode32) ? PATMFL_CODE32 : 0);
815 if (VBOX_FAILURE(rc))
816 {
817 Log(("PATMR3InstallPatch failed with %d\n", rc));
818 return VWRN_CONTINUE_ANALYSIS;
819 }
820 }
821 if (pCpu->pCurInstr->opcode == OP_IRET)
822 return VINF_SUCCESS; /* Look no further in this branch. */
823
824 return VWRN_CONTINUE_ANALYSIS;
825
826 case OP_JMP:
827 case OP_CALL:
828 {
829 // return or jump/call through a jump table
830 if (OP_PARM_VTYPE(pCpu->pCurInstr->param1) != OP_PARM_J)
831 {
832#ifdef DEBUG
833 switch(pCpu->pCurInstr->opcode)
834 {
835 case OP_JMP:
836 Log(("Control Flow instruction at %VRv: jmp!!\n", pCurInstrGC));
837 break;
838 case OP_CALL:
839 Log(("Control Flow instruction at %VRv: call!!\n", pCurInstrGC));
840 break;
841 }
842#endif
843 return VWRN_CONTINUE_ANALYSIS;
844 }
845 return VWRN_CONTINUE_ANALYSIS;
846 }
847
848 }
849
850 return VWRN_CONTINUE_ANALYSIS;
851}
852
853#ifdef CSAM_ANALYSE_BEYOND_RET
854/**
855 * Wrapper for csamAnalyseCodeStream for call instructions.
856 *
857 * @returns VBox status code.
858 * @param pVM The VM to operate on.
859 * @param pInstrGC Guest context pointer to privileged instruction
860 * @param pCurInstrGC Guest context pointer to the current instruction
861 * @param fCode32 16 or 32 bits code
862 * @param pfnCSAMR3Analyse Callback for testing the disassembled instruction
863 * @param pUserData User pointer (callback specific)
864 *
865 */
866static int csamAnalyseCallCodeStream(PVM pVM, RCPTRTYPE(uint8_t *) pInstrGC, RCPTRTYPE(uint8_t *) pCurInstrGC, bool fCode32,
867 PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec)
868{
869 int rc;
870 CSAMCALLEXITREC CallExitRec;
871 PCSAMCALLEXITREC pOldCallRec;
872 PCSAMPAGE pPage = 0;
873 uint32_t i;
874
875 CallExitRec.cInstrAfterRet = 0;
876
877 pOldCallRec = pCacheRec->pCallExitRec;
878 pCacheRec->pCallExitRec = &CallExitRec;
879
880 rc = csamAnalyseCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
881
882 for (i=0;i<CallExitRec.cInstrAfterRet;i++)
883 {
884 PCSAMPAGE pPage = 0;
885
886 pCurInstrGC = CallExitRec.pInstrAfterRetGC[i];
887
888 /* Check if we've previously encountered the instruction after the ret. */
889 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
890 {
891 DISCPUSTATE cpu;
892 uint32_t opsize;
893 uint8_t *pCurInstrHC = 0;
894 int rc2;
895#ifdef DEBUG
896 char szOutput[256];
897#endif
898 if (pPage == NULL)
899 {
900 /* New address; let's take a look at it. */
901 pPage = csamCreatePageRecord(pVM, pCurInstrGC, CSAM_TAG_CSAM, fCode32);
902 if (pPage == NULL)
903 {
904 rc = VERR_NO_MEMORY;
905 goto done;
906 }
907 }
908
909 /**
910 * Some generic requirements for recognizing an adjacent function:
911 * - alignment fillers that consist of:
912 * - nop
913 * - lea genregX, [genregX (+ 0)]
914 * - push ebp after the filler (can extend this later); aligned at at least a 4 byte boundary
915 */
916 for (int j=0;j<16;j++)
917 {
918 pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
919 if (pCurInstrHC == NULL)
920 {
921 Log(("CSAMGCVirtToHCVirt failed for %VRv\n", pCurInstrGC));
922 goto done;
923 }
924 Assert(VALID_PTR(pCurInstrHC));
925
926 cpu.mode = (fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
927 STAM_PROFILE_START(&pVM->csam.s.StatTimeDisasm, a);
928#ifdef DEBUG
929 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, szOutput);
930 if (VBOX_SUCCESS(rc2)) Log(("CSAM Call Analysis: %s", szOutput));
931#else
932 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
933#endif
934 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeDisasm, a);
935 if (VBOX_FAILURE(rc2))
936 {
937 Log(("Disassembly failed at %VRv with %Vrc (probably page not present) -> return to caller\n", pCurInstrGC, rc2));
938 goto done;
939 }
940
941 STAM_COUNTER_ADD(&pVM->csam.s.StatNrBytesRead, opsize);
942
943 RCPTRTYPE(uint8_t *) addr = 0;
944 PCSAMPAGE pJmpPage = NULL;
945
946 if (PAGE_ADDRESS(pCurInstrGC) != PAGE_ADDRESS(pCurInstrGC + opsize - 1))
947 {
948 if (!PGMGstIsPagePresent(pVM, pCurInstrGC + opsize - 1))
949 {
950 /// @todo fault in the page
951 Log(("Page for current instruction %VRv is not present!!\n", pCurInstrGC));
952 goto done;
953 }
954 //all is fine, let's continue
955 csamR3CheckPageRecord(pVM, pCurInstrGC + opsize - 1);
956 }
957
958 switch (cpu.pCurInstr->opcode)
959 {
960 case OP_NOP:
961 case OP_INT3:
962 break; /* acceptable */
963
964 case OP_LEA:
965 /* Must be similar to:
966 *
967 * lea esi, [esi]
968 * lea esi, [esi+0]
969 * Any register is allowed as long as source and destination are identical.
970 */
971 if ( cpu.param1.flags != USE_REG_GEN32
972 || ( cpu.param2.flags != USE_REG_GEN32
973 && ( !(cpu.param2.flags & USE_REG_GEN32)
974 || !(cpu.param2.flags & (USE_DISPLACEMENT8|USE_DISPLACEMENT16|USE_DISPLACEMENT32))
975 || cpu.param2.parval != 0
976 )
977 )
978 || cpu.param1.base.reg_gen32 != cpu.param2.base.reg_gen32
979 )
980 {
981 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
982 goto next_function;
983 }
984 break;
985
986 case OP_PUSH:
987 {
988 if ( (pCurInstrGC & 0x3) != 0
989 || cpu.param1.flags != USE_REG_GEN32
990 || cpu.param1.base.reg_gen32 != USE_REG_EBP
991 )
992 {
993 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
994 goto next_function;
995 }
996
997 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
998 {
999 CSAMCALLEXITREC CallExitRec2;
1000 CallExitRec2.cInstrAfterRet = 0;
1001
1002 pCacheRec->pCallExitRec = &CallExitRec2;
1003
1004 /* Analyse the function. */
1005 Log(("Found new function at %VRv\n", pCurInstrGC));
1006 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunction);
1007 csamAnalyseCallCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
1008 }
1009 goto next_function;
1010 }
1011
1012 case OP_SUB:
1013 {
1014 if ( (pCurInstrGC & 0x3) != 0
1015 || cpu.param1.flags != USE_REG_GEN32
1016 || cpu.param1.base.reg_gen32 != USE_REG_ESP
1017 )
1018 {
1019 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
1020 goto next_function;
1021 }
1022
1023 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
1024 {
1025 CSAMCALLEXITREC CallExitRec2;
1026 CallExitRec2.cInstrAfterRet = 0;
1027
1028 pCacheRec->pCallExitRec = &CallExitRec2;
1029
1030 /* Analyse the function. */
1031 Log(("Found new function at %VRv\n", pCurInstrGC));
1032 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunction);
1033 csamAnalyseCallCodeStream(pVM, pInstrGC, pCurInstrGC, fCode32, pfnCSAMR3Analyse, pUserData, pCacheRec);
1034 }
1035 goto next_function;
1036 }
1037
1038 default:
1039 STAM_COUNTER_INC(&pVM->csam.s.StatScanNextFunctionFailed);
1040 goto next_function;
1041 }
1042 /* Mark it as scanned. */
1043 csamMarkCode(pVM, pPage, pCurInstrGC, opsize, true);
1044 pCurInstrGC += opsize;
1045 } /* for at most 16 instructions */
1046next_function:
1047 ; /* MSVC complains otherwise */
1048 }
1049 }
1050done:
1051 pCacheRec->pCallExitRec = pOldCallRec;
1052 return rc;
1053}
1054#else
1055#define csamAnalyseCallCodeStream csamAnalyseCodeStream
1056#endif
1057
1058/**
1059 * Disassembles the code stream until the callback function detects a failure or decides everything is acceptable
1060 *
1061 * @returns VBox status code.
1062 * @param pVM The VM to operate on.
1063 * @param pInstrGC Guest context pointer to privileged instruction
1064 * @param pCurInstrGC Guest context pointer to the current instruction
1065 * @param fCode32 16 or 32 bits code
1066 * @param pfnCSAMR3Analyse Callback for testing the disassembled instruction
1067 * @param pUserData User pointer (callback specific)
1068 *
1069 */
1070static int csamAnalyseCodeStream(PVM pVM, RCPTRTYPE(uint8_t *) pInstrGC, RCPTRTYPE(uint8_t *) pCurInstrGC, bool fCode32,
1071 PFN_CSAMR3ANALYSE pfnCSAMR3Analyse, void *pUserData, PCSAMP2GLOOKUPREC pCacheRec)
1072{
1073 DISCPUSTATE cpu;
1074 PCSAMPAGE pPage = (PCSAMPAGE)pUserData;
1075 int rc = VWRN_CONTINUE_ANALYSIS;
1076 uint32_t opsize;
1077 R3PTRTYPE(uint8_t *) pCurInstrHC = 0;
1078 int rc2;
1079
1080#ifdef DEBUG
1081 char szOutput[256];
1082#endif
1083
1084 LogFlow(("csamAnalyseCodeStream: code at %VRv depth=%d\n", pCurInstrGC, pCacheRec->depth));
1085
1086 pVM->csam.s.fScanningStarted = true;
1087
1088 pCacheRec->depth++;
1089 /*
1090 * Limit the call depth. (rather arbitrary upper limit; too low and we won't detect certain
1091 * cpuid instructions in Linux kernels; too high and we waste too much time scanning code)
1092 * (512 is necessary to detect cpuid instructions in Red Hat EL4; see defect 1355)
1093 * @note we are using a lot of stack here. couple of 100k when we go to the full depth (!)
1094 */
1095 if (pCacheRec->depth > 512)
1096 {
1097 LogFlow(("CSAM: maximum calldepth reached for %VRv\n", pCurInstrGC));
1098 pCacheRec->depth--;
1099 return VINF_SUCCESS; //let's not go on forever
1100 }
1101
1102 Assert(!PATMIsPatchGCAddr(pVM, pCurInstrGC));
1103 csamR3CheckPageRecord(pVM, pCurInstrGC);
1104
1105 while(rc == VWRN_CONTINUE_ANALYSIS)
1106 {
1107 if (csamIsCodeScanned(pVM, pCurInstrGC, &pPage) == false)
1108 {
1109 if (pPage == NULL)
1110 {
1111 /* New address; let's take a look at it. */
1112 pPage = csamCreatePageRecord(pVM, pCurInstrGC, CSAM_TAG_CSAM, fCode32);
1113 if (pPage == NULL)
1114 {
1115 rc = VERR_NO_MEMORY;
1116 goto done;
1117 }
1118 }
1119 }
1120 else
1121 {
1122 LogFlow(("Code at %VRv has been scanned before\n", pCurInstrGC));
1123 rc = VINF_SUCCESS;
1124 goto done;
1125 }
1126
1127 pCurInstrHC = (uint8_t *)CSAMGCVirtToHCVirt(pVM, pCacheRec, pCurInstrGC);
1128 if (pCurInstrHC == NULL)
1129 {
1130 Log(("CSAMGCVirtToHCVirt failed for %VRv\n", pCurInstrGC));
1131 rc = VERR_PATCHING_REFUSED;
1132 goto done;
1133 }
1134 Assert(VALID_PTR(pCurInstrHC));
1135
1136 cpu.mode = (fCode32) ? CPUMODE_32BIT : CPUMODE_16BIT;
1137 STAM_PROFILE_START(&pVM->csam.s.StatTimeDisasm, a);
1138#ifdef DEBUG
1139 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, szOutput);
1140 if (VBOX_SUCCESS(rc2)) Log(("CSAM Analysis: %s", szOutput));
1141#else
1142 rc2 = CSAMR3DISInstr(pVM, &cpu, pCurInstrGC, pCurInstrHC, &opsize, NULL);
1143#endif
1144 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeDisasm, a);
1145 if (VBOX_FAILURE(rc2))
1146 {
1147 Log(("Disassembly failed at %VRv with %Vrc (probably page not present) -> return to caller\n", pCurInstrGC, rc2));
1148 rc = VINF_SUCCESS;
1149 goto done;
1150 }
1151
1152 STAM_COUNTER_ADD(&pVM->csam.s.StatNrBytesRead, opsize);
1153
1154 csamMarkCode(pVM, pPage, pCurInstrGC, opsize, true);
1155
1156 RCPTRTYPE(uint8_t *) addr = 0;
1157 PCSAMPAGE pJmpPage = NULL;
1158
1159 if (PAGE_ADDRESS(pCurInstrGC) != PAGE_ADDRESS(pCurInstrGC + opsize - 1))
1160 {
1161 if (!PGMGstIsPagePresent(pVM, pCurInstrGC + opsize - 1))
1162 {
1163 /// @todo fault in the page
1164 Log(("Page for current instruction %VRv is not present!!\n", pCurInstrGC));
1165 rc = VWRN_CONTINUE_ANALYSIS;
1166 goto next_please;
1167 }
1168 //all is fine, let's continue
1169 csamR3CheckPageRecord(pVM, pCurInstrGC + opsize - 1);
1170 }
1171 /*
1172 * If it's harmless, then don't bother checking it (the disasm tables had better be accurate!)
1173 */
1174 if ((cpu.pCurInstr->optype & ~OPTYPE_RRM_MASK) == OPTYPE_HARMLESS)
1175 {
1176 AssertMsg(pfnCSAMR3Analyse(pVM, &cpu, pInstrGC, pCurInstrGC, pCacheRec, (void *)pPage) == VWRN_CONTINUE_ANALYSIS, ("Instruction incorrectly marked harmless?!?!?\n"));
1177 rc = VWRN_CONTINUE_ANALYSIS;
1178 goto next_please;
1179 }
1180
1181#ifdef CSAM_ANALYSE_BEYOND_RET
1182 /* Remember the address of the instruction following the ret in case the parent instruction was a call. */
1183 if ( pCacheRec->pCallExitRec
1184 && cpu.pCurInstr->opcode == OP_RETN
1185 && pCacheRec->pCallExitRec->cInstrAfterRet < CSAM_MAX_CALLEXIT_RET)
1186 {
1187 pCacheRec->pCallExitRec->pInstrAfterRetGC[pCacheRec->pCallExitRec->cInstrAfterRet] = pCurInstrGC + opsize;
1188 pCacheRec->pCallExitRec->cInstrAfterRet++;
1189 }
1190#endif
1191
1192 rc = pfnCSAMR3Analyse(pVM, &cpu, pInstrGC, pCurInstrGC, pCacheRec, (void *)pPage);
1193 if (rc == VINF_SUCCESS)
1194 goto done;
1195
1196 // For our first attempt, we'll handle only simple relative jumps and calls (immediate offset coded in instruction)
1197 if ( ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1198 || (cpu.pCurInstr->opcode == OP_CALL && cpu.param1.flags == USE_DISPLACEMENT32)) /* simple indirect call (call dword ptr [address]) */
1199 {
1200 /* 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) */
1201 if ( cpu.pCurInstr->opcode == OP_CALL
1202 && cpu.param1.flags == USE_DISPLACEMENT32)
1203 {
1204 addr = 0;
1205 PGMPhysReadGCPtr(pVM, &addr, (RTRCUINTPTR)cpu.param1.disp32, sizeof(addr));
1206 }
1207 else
1208 addr = CSAMResolveBranch(&cpu, pCurInstrGC);
1209
1210 if (addr == 0)
1211 {
1212 Log(("We don't support far jumps here!! (%08X)\n", cpu.param1.flags));
1213 rc = VINF_SUCCESS;
1214 break;
1215 }
1216 Assert(!PATMIsPatchGCAddr(pVM, addr));
1217
1218 /* If the target address lies in a patch generated jump, then special action needs to be taken. */
1219 PATMR3DetectConflict(pVM, pCurInstrGC, addr);
1220
1221 /* Same page? */
1222 if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pCurInstrGC ))
1223 {
1224 if (!PGMGstIsPagePresent(pVM, addr))
1225 {
1226 Log(("Page for current instruction %VRv is not present!!\n", addr));
1227 rc = VWRN_CONTINUE_ANALYSIS;
1228 goto next_please;
1229 }
1230
1231 /* All is fine, let's continue. */
1232 csamR3CheckPageRecord(pVM, addr);
1233 }
1234
1235 pJmpPage = NULL;
1236 if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1237 {
1238 if (pJmpPage == NULL)
1239 {
1240 /* New branch target; let's take a look at it. */
1241 pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1242 if (pJmpPage == NULL)
1243 {
1244 rc = VERR_NO_MEMORY;
1245 goto done;
1246 }
1247 Assert(pPage);
1248 }
1249 if (cpu.pCurInstr->opcode == OP_CALL)
1250 rc = csamAnalyseCallCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1251 else
1252 rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1253
1254 if (rc != VINF_SUCCESS) {
1255 goto done;
1256 }
1257 }
1258 if (cpu.pCurInstr->opcode == OP_JMP)
1259 {//unconditional jump; return to caller
1260 rc = VINF_SUCCESS;
1261 goto done;
1262 }
1263
1264 rc = VWRN_CONTINUE_ANALYSIS;
1265 } //if ((cpu.pCurInstr->optype & OPTYPE_CONTROLFLOW) && (OP_PARM_VTYPE(cpu.pCurInstr->param1) == OP_PARM_J))
1266#ifdef CSAM_SCAN_JUMP_TABLE
1267 else
1268 if ( cpu.pCurInstr->opcode == OP_JMP
1269 && (cpu.param1.flags & (USE_DISPLACEMENT32|USE_INDEX|USE_SCALE)) == (USE_DISPLACEMENT32|USE_INDEX|USE_SCALE)
1270 )
1271 {
1272 RTRCPTR pJumpTableGC = (RTRCPTR)cpu.param1.disp32;
1273 uint8_t *pJumpTableHC;
1274 int rc2;
1275
1276 Log(("Jump through jump table\n"));
1277
1278 rc2 = PGMPhysGCPtr2HCPtr(pVM, pJumpTableGC, (PRTHCPTR)&pJumpTableHC);
1279 if (rc2 == VINF_SUCCESS)
1280 {
1281 for (uint32_t i=0;i<2;i++)
1282 {
1283 uint64_t fFlags;
1284
1285 addr = pJumpTableGC + cpu.param1.scale * i;
1286 /* Same page? */
1287 if (PAGE_ADDRESS(addr) != PAGE_ADDRESS(pJumpTableGC))
1288 break;
1289
1290 addr = *(RTRCPTR *)(pJumpTableHC + cpu.param1.scale * i);
1291
1292 rc2 = PGMGstGetPage(pVM, addr, &fFlags, NULL);
1293 if ( rc2 != VINF_SUCCESS
1294 || (fFlags & X86_PTE_US)
1295 || !(fFlags & X86_PTE_P)
1296 )
1297 break;
1298
1299 Log(("Jump to %VRv\n", addr));
1300
1301 pJmpPage = NULL;
1302 if (csamIsCodeScanned(pVM, addr, &pJmpPage) == false)
1303 {
1304 if (pJmpPage == NULL)
1305 {
1306 /* New branch target; let's take a look at it. */
1307 pJmpPage = csamCreatePageRecord(pVM, addr, CSAM_TAG_CSAM, fCode32);
1308 if (pJmpPage == NULL)
1309 {
1310 rc = VERR_NO_MEMORY;
1311 goto done;
1312 }
1313 Assert(pPage);
1314 }
1315 rc = csamAnalyseCodeStream(pVM, pInstrGC, addr, fCode32, pfnCSAMR3Analyse, (void *)pJmpPage, pCacheRec);
1316 if (rc != VINF_SUCCESS) {
1317 goto done;
1318 }
1319 }
1320 }
1321 }
1322 }
1323#endif
1324 if (rc != VWRN_CONTINUE_ANALYSIS) {
1325 break; //done!
1326 }
1327next_please:
1328 if (cpu.pCurInstr->opcode == OP_JMP)
1329 {
1330 rc = VINF_SUCCESS;
1331 goto done;
1332 }
1333 pCurInstrGC += opsize;
1334 }
1335done:
1336 pCacheRec->depth--;
1337 return rc;
1338}
1339
1340
1341/**
1342 * Calculates the 64 bits hash value for the current page
1343 *
1344 * @returns hash value
1345 * @param pVM The VM to operate on.
1346 * @param pInstr Page address
1347 */
1348uint64_t csamR3CalcPageHash(PVM pVM, RTRCPTR pInstr)
1349{
1350 uint64_t hash = 0;
1351 uint32_t val[5];
1352 int rc;
1353
1354 Assert((pInstr & PAGE_OFFSET_MASK) == 0);
1355
1356 rc = PGMPhysReadGCPtr(pVM, &val[0], pInstr, sizeof(val[0]));
1357 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1358 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1359 {
1360 Log(("csamR3CalcPageHash: page %VRv not present!!\n", pInstr));
1361 return ~0ULL;
1362 }
1363
1364 rc = PGMPhysReadGCPtr(pVM, &val[1], pInstr+1024, sizeof(val[0]));
1365 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1366 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1367 {
1368 Log(("csamR3CalcPageHash: page %VRv not present!!\n", pInstr));
1369 return ~0ULL;
1370 }
1371
1372 rc = PGMPhysReadGCPtr(pVM, &val[2], pInstr+2048, sizeof(val[0]));
1373 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1374 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1375 {
1376 Log(("csamR3CalcPageHash: page %VRv not present!!\n", pInstr));
1377 return ~0ULL;
1378 }
1379
1380 rc = PGMPhysReadGCPtr(pVM, &val[3], pInstr+3072, sizeof(val[0]));
1381 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1382 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1383 {
1384 Log(("csamR3CalcPageHash: page %VRv not present!!\n", pInstr));
1385 return ~0ULL;
1386 }
1387
1388 rc = PGMPhysReadGCPtr(pVM, &val[4], pInstr+4092, sizeof(val[0]));
1389 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1390 if (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1391 {
1392 Log(("csamR3CalcPageHash: page %VRv not present!!\n", pInstr));
1393 return ~0ULL;
1394 }
1395
1396 // don't want to get division by zero traps
1397 val[2] |= 1;
1398 val[4] |= 1;
1399
1400 hash = (uint64_t)val[0] * (uint64_t)val[1] / (uint64_t)val[2] + (val[3]%val[4]);
1401 return (hash == ~0ULL) ? hash - 1 : hash;
1402}
1403
1404
1405/**
1406 * Notify CSAM of a page flush
1407 *
1408 * @returns VBox status code
1409 * @param pVM The VM to operate on.
1410 * @param addr GC address of the page to flush
1411 * @param fRemovePage Page removal flag
1412 */
1413static int csamFlushPage(PVM pVM, RTRCPTR addr, bool fRemovePage)
1414{
1415 PCSAMPAGEREC pPageRec;
1416 int rc;
1417 RTGCPHYS GCPhys = 0;
1418 uint64_t fFlags = 0;
1419
1420 if (!CSAMIsEnabled(pVM))
1421 return VINF_SUCCESS;
1422
1423 STAM_PROFILE_START(&pVM->csam.s.StatTimeFlushPage, a);
1424
1425 addr = addr & PAGE_BASE_GC_MASK;
1426
1427 /*
1428 * Note: searching for the page in our tree first is more expensive (skipped flushes are two orders of magnitude more common)
1429 */
1430 if (pVM->csam.s.pPageTree == NULL)
1431 {
1432 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1433 return VWRN_CSAM_PAGE_NOT_FOUND;
1434 }
1435
1436 rc = PGMGstGetPage(pVM, addr, &fFlags, &GCPhys);
1437 /* Returned at a very early stage (no paging yet presumably). */
1438 if (rc == VERR_NOT_SUPPORTED)
1439 {
1440 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1441 return rc;
1442 }
1443
1444 if (VBOX_SUCCESS(rc))
1445 {
1446 if ( (fFlags & X86_PTE_US)
1447 || rc == VERR_PGM_PHYS_PAGE_RESERVED
1448 )
1449 {
1450 /* User page -> not relevant for us. */
1451 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1452 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1453 return VINF_SUCCESS;
1454 }
1455 }
1456 else
1457 if (rc != VERR_PAGE_NOT_PRESENT && rc != VERR_PAGE_TABLE_NOT_PRESENT)
1458 AssertMsgFailed(("PGMR3GetPage %VRv failed with %Vrc\n", addr, rc));
1459
1460 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1461 if (pPageRec)
1462 {
1463 if ( GCPhys == pPageRec->page.GCPhys
1464 && (fFlags & X86_PTE_P))
1465 {
1466 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushesSkipped, 1);
1467 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1468 return VINF_SUCCESS;
1469 }
1470
1471 Log(("CSAMR3FlushPage: page %VRv has changed -> FLUSH (rc=%Vrc) (Phys: %VGp vs %VGp)\n", addr, rc, GCPhys, pPageRec->page.GCPhys));
1472
1473 STAM_COUNTER_ADD(&pVM->csam.s.StatNrFlushes, 1);
1474
1475 if (fRemovePage)
1476 csamRemovePageRecord(pVM, addr);
1477 else
1478 {
1479 CSAMMarkPage(pVM, addr, false);
1480 pPageRec->page.GCPhys = 0;
1481 pPageRec->page.fFlags = 0;
1482 rc = PGMGstGetPage(pVM, addr, &pPageRec->page.fFlags, &pPageRec->page.GCPhys);
1483 if (rc == VINF_SUCCESS)
1484 pPageRec->page.u64Hash = csamR3CalcPageHash(pVM, addr);
1485
1486 if (pPageRec->page.pBitmap == NULL)
1487 {
1488 pPageRec->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, CSAM_PAGE_BITMAP_SIZE);
1489 Assert(pPageRec->page.pBitmap);
1490 if (pPageRec->page.pBitmap == NULL)
1491 return VERR_NO_MEMORY;
1492 }
1493 else
1494 memset(pPageRec->page.pBitmap, 0, CSAM_PAGE_BITMAP_SIZE);
1495 }
1496
1497
1498 /*
1499 * Inform patch manager about the flush; no need to repeat the above check twice.
1500 */
1501 PATMR3FlushPage(pVM, addr);
1502
1503 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1504 return VINF_SUCCESS;
1505 }
1506 else
1507 {
1508 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeFlushPage, a);
1509 return VWRN_CSAM_PAGE_NOT_FOUND;
1510 }
1511}
1512
1513/**
1514 * Notify CSAM of a page flush
1515 *
1516 * @returns VBox status code
1517 * @param pVM The VM to operate on.
1518 * @param addr GC address of the page to flush
1519 */
1520CSAMR3DECL(int) CSAMR3FlushPage(PVM pVM, RTRCPTR addr)
1521{
1522 return csamFlushPage(pVM, addr, true /* remove page record */);
1523}
1524
1525/**
1526 * Remove a CSAM monitored page. Use with care!
1527 *
1528 * @returns VBox status code
1529 * @param pVM The VM to operate on.
1530 * @param addr GC address of the page to flush
1531 */
1532CSAMR3DECL(int) CSAMR3RemovePage(PVM pVM, RTRCPTR addr)
1533{
1534 PCSAMPAGEREC pPageRec;
1535 int rc;
1536
1537 addr = addr & PAGE_BASE_GC_MASK;
1538
1539 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)addr);
1540 if (pPageRec)
1541 {
1542 rc = csamRemovePageRecord(pVM, addr);
1543 if (VBOX_SUCCESS(rc))
1544 PATMR3FlushPage(pVM, addr);
1545 return VINF_SUCCESS;
1546 }
1547 return VWRN_CSAM_PAGE_NOT_FOUND;
1548}
1549
1550/**
1551 * Check a page record in case a page has been changed
1552 *
1553 * @returns VBox status code. (trap handled or not)
1554 * @param pVM The VM to operate on.
1555 * @param pInstrGC GC instruction pointer
1556 */
1557int csamR3CheckPageRecord(PVM pVM, RTRCPTR pInstrGC)
1558{
1559 PCSAMPAGEREC pPageRec;
1560 uint64_t u64hash;
1561
1562 pInstrGC = pInstrGC & PAGE_BASE_GC_MASK;
1563
1564 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstrGC);
1565 if (pPageRec)
1566 {
1567 u64hash = csamR3CalcPageHash(pVM, pInstrGC);
1568 if (u64hash != pPageRec->page.u64Hash)
1569 csamFlushPage(pVM, pInstrGC, false /* don't remove page record */);
1570 }
1571 else
1572 return VWRN_CSAM_PAGE_NOT_FOUND;
1573
1574 return VINF_SUCCESS;
1575}
1576
1577/**
1578 * Returns monitor description based on CSAM tag
1579 *
1580 * @return description string
1581 * @param enmTag Owner tag
1582 */
1583const char *csamGetMonitorDescription(CSAMTAG enmTag)
1584{
1585 if (enmTag == CSAM_TAG_PATM)
1586 return "CSAM-PATM self-modifying code monitor handler";
1587 else
1588 if (enmTag == CSAM_TAG_REM)
1589 return "CSAM-REM self-modifying code monitor handler";
1590 Assert(enmTag == CSAM_TAG_CSAM);
1591 return "CSAM self-modifying code monitor handler";
1592}
1593
1594/**
1595 * Adds page record to our lookup tree
1596 *
1597 * @returns CSAMPAGE ptr or NULL if failure
1598 * @param pVM The VM to operate on.
1599 * @param GCPtr Page address
1600 * @param enmTag Owner tag
1601 * @param fCode32 16 or 32 bits code
1602 * @param fMonitorInvalidation Monitor page invalidation flag
1603 */
1604static PCSAMPAGE csamCreatePageRecord(PVM pVM, RTRCPTR GCPtr, CSAMTAG enmTag, bool fCode32, bool fMonitorInvalidation)
1605{
1606 PCSAMPAGEREC pPage;
1607 int rc;
1608 bool ret;
1609
1610 Log(("New page record for %VRv\n", GCPtr & PAGE_BASE_GC_MASK));
1611
1612 pPage = (PCSAMPAGEREC)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, sizeof(CSAMPAGEREC));
1613 if (pPage == NULL)
1614 {
1615 AssertMsgFailed(("csamCreatePageRecord: Out of memory!!!!\n"));
1616 return NULL;
1617 }
1618 /* Round down to page boundary. */
1619 GCPtr = (GCPtr & PAGE_BASE_GC_MASK);
1620 pPage->Core.Key = (AVLPVKEY)GCPtr;
1621 pPage->page.pPageGC = GCPtr;
1622 pPage->page.fCode32 = fCode32;
1623 pPage->page.fMonitorInvalidation = fMonitorInvalidation;
1624 pPage->page.enmTag = enmTag;
1625 pPage->page.fMonitorActive = false;
1626 pPage->page.pBitmap = (uint8_t *)MMR3HeapAllocZ(pVM, MM_TAG_CSAM_PATCH, PAGE_SIZE/sizeof(uint8_t));
1627 rc = PGMGstGetPage(pVM, GCPtr, &pPage->page.fFlags, &pPage->page.GCPhys);
1628 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1629
1630 pPage->page.u64Hash = csamR3CalcPageHash(pVM, GCPtr);
1631 ret = RTAvlPVInsert(&pVM->csam.s.pPageTree, &pPage->Core);
1632 Assert(ret);
1633
1634#ifdef CSAM_MONITOR_CODE_PAGES
1635 AssertRelease(!fInCSAMCodePageInvalidate);
1636
1637 switch (enmTag)
1638 {
1639 case CSAM_TAG_PATM:
1640 case CSAM_TAG_REM:
1641#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1642 case CSAM_TAG_CSAM:
1643#endif
1644 {
1645 int rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GCPtr, GCPtr + (PAGE_SIZE - 1) /* inclusive! */,
1646 (fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1647 csamGetMonitorDescription(enmTag));
1648 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VRv failed with %Vrc\n", GCPtr, rc));
1649 if (VBOX_FAILURE(rc))
1650 Log(("PGMR3HandlerVirtualRegisterEx for %VRv failed with %Vrc\n", GCPtr, rc));
1651
1652 /* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1653
1654 /* Prefetch it in case it's not there yet. */
1655 rc = PGMPrefetchPage(pVM, GCPtr);
1656 AssertRC(rc);
1657
1658 rc = PGMShwModifyPage(pVM, GCPtr, 1, 0, ~(uint64_t)X86_PTE_RW);
1659 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1660
1661 pPage->page.fMonitorActive = true;
1662 STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1663 break;
1664 }
1665 default:
1666 break; /* to shut up GCC */
1667 }
1668
1669 Log(("csamCreatePageRecord %VRv HCPhys=%VGp\n", GCPtr, pPage->page.GCPhys));
1670
1671#ifdef VBOX_WITH_STATISTICS
1672 switch (enmTag)
1673 {
1674 case CSAM_TAG_CSAM:
1675 STAM_COUNTER_INC(&pVM->csam.s.StatPageCSAM);
1676 break;
1677 case CSAM_TAG_PATM:
1678 STAM_COUNTER_INC(&pVM->csam.s.StatPagePATM);
1679 break;
1680 case CSAM_TAG_REM:
1681 STAM_COUNTER_INC(&pVM->csam.s.StatPageREM);
1682 break;
1683 default:
1684 break; /* to shut up GCC */
1685 }
1686#endif
1687
1688#endif
1689
1690 STAM_COUNTER_INC(&pVM->csam.s.StatNrPages);
1691 if (fMonitorInvalidation)
1692 STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1693
1694 return &pPage->page;
1695}
1696
1697/**
1698 * Monitors a code page (if not already monitored)
1699 *
1700 * @returns VBox status code
1701 * @param pVM The VM to operate on.
1702 * @param pPageAddrGC The page to monitor
1703 * @param enmTag Monitor tag
1704 */
1705CSAMR3DECL(int) CSAMR3MonitorPage(PVM pVM, RTRCPTR pPageAddrGC, CSAMTAG enmTag)
1706{
1707 PCSAMPAGEREC pPageRec = NULL;
1708 int rc;
1709 bool fMonitorInvalidation;
1710
1711 /* Dirty pages must be handled before calling this function!. */
1712 Assert(!pVM->csam.s.cDirtyPages);
1713
1714 if (pVM->csam.s.fScanningStarted == false)
1715 return VINF_SUCCESS; /* too early */
1716
1717 pPageAddrGC &= PAGE_BASE_GC_MASK;
1718
1719 Log(("CSAMR3MonitorPage %VRv %d\n", pPageAddrGC, enmTag));
1720
1721 /** @todo implicit assumption */
1722 fMonitorInvalidation = (enmTag == CSAM_TAG_PATM);
1723
1724 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1725 if (pPageRec == NULL)
1726 {
1727 uint64_t fFlags;
1728
1729 rc = PGMGstGetPage(pVM, pPageAddrGC, &fFlags, NULL);
1730 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
1731 if ( rc == VINF_SUCCESS
1732 && (fFlags & X86_PTE_US))
1733 {
1734 /* We don't care about user pages. */
1735 STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
1736 return VINF_SUCCESS;
1737 }
1738
1739 csamCreatePageRecord(pVM, pPageAddrGC, enmTag, true /* 32 bits code */, fMonitorInvalidation);
1740
1741 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1742 Assert(pPageRec);
1743 }
1744 /** @todo reference count */
1745
1746#ifdef CSAM_MONITOR_CSAM_CODE_PAGES
1747 Assert(pPageRec->page.fMonitorActive);
1748#endif
1749
1750#ifdef CSAM_MONITOR_CODE_PAGES
1751 if (!pPageRec->page.fMonitorActive)
1752 {
1753 Log(("CSAMR3MonitorPage: activate monitoring for %VRv\n", pPageAddrGC));
1754
1755 rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, pPageAddrGC, pPageAddrGC + (PAGE_SIZE - 1) /* inclusive! */,
1756 (fMonitorInvalidation) ? CSAMCodePageInvalidate : 0, CSAMCodePageWriteHandler, "CSAMGCCodePageWriteHandler", 0,
1757 csamGetMonitorDescription(enmTag));
1758 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT, ("PGMR3HandlerVirtualRegisterEx %VRv failed with %Vrc\n", pPageAddrGC, rc));
1759 if (VBOX_FAILURE(rc))
1760 Log(("PGMR3HandlerVirtualRegisterEx for %VRv failed with %Vrc\n", pPageAddrGC, rc));
1761
1762 /* Could fail, because it's already monitored. Don't treat that condition as fatal. */
1763
1764 /* Prefetch it in case it's not there yet. */
1765 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1766 AssertRC(rc);
1767
1768 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1769 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1770
1771 STAM_COUNTER_INC(&pVM->csam.s.StatPageMonitor);
1772
1773 pPageRec->page.fMonitorActive = true;
1774 pPageRec->page.fMonitorInvalidation = fMonitorInvalidation;
1775 }
1776 else
1777 if ( !pPageRec->page.fMonitorInvalidation
1778 && fMonitorInvalidation)
1779 {
1780 Assert(pPageRec->page.fMonitorActive);
1781 PGMHandlerVirtualChangeInvalidateCallback(pVM, pPageRec->page.pPageGC, CSAMCodePageInvalidate);
1782 pPageRec->page.fMonitorInvalidation = true;
1783 STAM_COUNTER_INC(&pVM->csam.s.StatNrPagesInv);
1784
1785 /* Prefetch it in case it's not there yet. */
1786 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1787 AssertRC(rc);
1788
1789 /* Make sure it's readonly. Page invalidation may have modified the attributes. */
1790 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1791 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1792 }
1793
1794#if 0 /* def VBOX_STRICT -> very annoying) */
1795 if (pPageRec->page.fMonitorActive)
1796 {
1797 uint64_t fPageShw;
1798 RTHCPHYS GCPhys;
1799 rc = PGMShwGetPage(pVM, pPageAddrGC, &fPageShw, &GCPhys);
1800// AssertMsg( (rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT)
1801// || !(fPageShw & X86_PTE_RW)
1802// || (pPageRec->page.GCPhys == 0), ("Shadow page flags for %VRv (%VHp) aren't readonly (%VX64)!!\n", pPageAddrGC, GCPhys, fPageShw));
1803 }
1804#endif
1805
1806 if (pPageRec->page.GCPhys == 0)
1807 {
1808 /* Prefetch it in case it's not there yet. */
1809 rc = PGMPrefetchPage(pVM, pPageAddrGC);
1810 AssertRC(rc);
1811 /* The page was changed behind our back. It won't be made read-only until the next SyncCR3, so force it here. */
1812 rc = PGMShwModifyPage(pVM, pPageAddrGC, 1, 0, ~(uint64_t)X86_PTE_RW);
1813 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
1814 }
1815#endif /* CSAM_MONITOR_CODE_PAGES */
1816 return VINF_SUCCESS;
1817}
1818
1819/**
1820 * Unmonitors a code page
1821 *
1822 * @returns VBox status code
1823 * @param pVM The VM to operate on.
1824 * @param pPageAddrGC The page to monitor
1825 * @param enmTag Monitor tag
1826 */
1827CSAMR3DECL(int) CSAMR3UnmonitorPage(PVM pVM, RTRCPTR pPageAddrGC, CSAMTAG enmTag)
1828{
1829 pPageAddrGC &= PAGE_BASE_GC_MASK;
1830
1831 Log(("CSAMR3UnmonitorPage %VRv %d\n", pPageAddrGC, enmTag));
1832
1833 Assert(enmTag == CSAM_TAG_REM);
1834
1835#ifdef VBOX_STRICT
1836 PCSAMPAGEREC pPageRec;
1837
1838 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pPageAddrGC);
1839 Assert(pPageRec && pPageRec->page.enmTag == enmTag);
1840#endif
1841 return CSAMR3RemovePage(pVM, pPageAddrGC);
1842}
1843
1844/**
1845 * Removes a page record from our lookup tree
1846 *
1847 * @returns VBox status code
1848 * @param pVM The VM to operate on.
1849 * @param GCPtr Page address
1850 */
1851static int csamRemovePageRecord(PVM pVM, RTRCPTR GCPtr)
1852{
1853 PCSAMPAGEREC pPageRec;
1854
1855 Log(("csamRemovePageRecord %VRv\n", GCPtr));
1856 pPageRec = (PCSAMPAGEREC)RTAvlPVRemove(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
1857
1858 if (pPageRec)
1859 {
1860 STAM_COUNTER_INC(&pVM->csam.s.StatNrRemovedPages);
1861
1862#ifdef CSAM_MONITOR_CODE_PAGES
1863 if (pPageRec->page.fMonitorActive)
1864 {
1865 /* @todo -> this is expensive (cr3 reload)!!!
1866 * if this happens often, then reuse it instead!!!
1867 */
1868 Assert(!fInCSAMCodePageInvalidate);
1869 STAM_COUNTER_DEC(&pVM->csam.s.StatPageMonitor);
1870 PGMHandlerVirtualDeregister(pVM, GCPtr);
1871 }
1872 if (pPageRec->page.enmTag == CSAM_TAG_PATM)
1873 {
1874 /* Make sure the recompiler flushes its cache as this page is no longer monitored. */
1875 STAM_COUNTER_INC(&pVM->csam.s.StatPageRemoveREMFlush);
1876 CPUMSetChangedFlags(pVM, CPUM_CHANGED_GLOBAL_TLB_FLUSH);
1877 }
1878#endif
1879
1880#ifdef VBOX_WITH_STATISTICS
1881 switch (pPageRec->page.enmTag)
1882 {
1883 case CSAM_TAG_CSAM:
1884 STAM_COUNTER_DEC(&pVM->csam.s.StatPageCSAM);
1885 break;
1886 case CSAM_TAG_PATM:
1887 STAM_COUNTER_DEC(&pVM->csam.s.StatPagePATM);
1888 break;
1889 case CSAM_TAG_REM:
1890 STAM_COUNTER_DEC(&pVM->csam.s.StatPageREM);
1891 break;
1892 default:
1893 break; /* to shut up GCC */
1894 }
1895#endif
1896
1897 if (pPageRec->page.pBitmap) MMR3HeapFree(pPageRec->page.pBitmap);
1898 MMR3HeapFree(pPageRec);
1899 }
1900 else
1901 AssertFailed();
1902
1903 return VINF_SUCCESS;
1904}
1905
1906/**
1907 * Callback for delayed writes from non-EMT threads
1908 *
1909 * @param pVM VM Handle.
1910 * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1911 * @param cbBuf How much it's reading/writing.
1912 */
1913static DECLCALLBACK(void) CSAMDelayedWriteHandler(PVM pVM, RTRCPTR GCPtr, size_t cbBuf)
1914{
1915 int rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1916 AssertRC(rc);
1917}
1918
1919/**
1920 * #PF Handler callback for virtual access handler ranges.
1921 *
1922 * Important to realize that a physical page in a range can have aliases, and
1923 * for ALL and WRITE handlers these will also trigger.
1924 *
1925 * @returns VINF_SUCCESS if the handler have carried out the operation.
1926 * @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation.
1927 * @param pVM VM Handle.
1928 * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!)
1929 * @param pvPtr The HC mapping of that address.
1930 * @param pvBuf What the guest is reading/writing.
1931 * @param cbBuf How much it's reading/writing.
1932 * @param enmAccessType The access type.
1933 * @param pvUser User argument.
1934 */
1935static DECLCALLBACK(int) CSAMCodePageWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser)
1936{
1937 int rc;
1938
1939 Assert(enmAccessType == PGMACCESSTYPE_WRITE);
1940 Log(("CSAMCodePageWriteHandler: write to %VGv size=%d\n", GCPtr, cbBuf));
1941
1942 if (VM_IS_EMT(pVM))
1943 {
1944 rc = PATMR3PatchWrite(pVM, GCPtr, cbBuf);
1945 }
1946 else
1947 {
1948 /* Queue the write instead otherwise we'll get concurrency issues. */
1949 /** @note in theory not correct to let it write the data first before disabling a patch!
1950 * (if it writes the same data as the patch jump and we replace it with obsolete opcodes)
1951 */
1952 Log(("CSAMCodePageWriteHandler: delayed write!\n"));
1953 AssertCompileSize(RTRCPTR, 4);
1954 rc = VMR3ReqCallEx(pVM, NULL, 0, VMREQFLAGS_NO_WAIT | VMREQFLAGS_VOID,
1955 (PFNRT)CSAMDelayedWriteHandler, 3, pVM, (RTRCPTR)GCPtr, cbBuf);
1956 }
1957 AssertRC(rc);
1958
1959 return VINF_PGM_HANDLER_DO_DEFAULT;
1960}
1961
1962/**
1963 * #PF Handler callback for invalidation of virtual access handler ranges.
1964 *
1965 * @param pVM VM Handle.
1966 * @param GCPtr The virtual address the guest has changed.
1967 */
1968static DECLCALLBACK(int) CSAMCodePageInvalidate(PVM pVM, RTGCPTR GCPtr)
1969{
1970 fInCSAMCodePageInvalidate = true;
1971 LogFlow(("CSAMCodePageInvalidate %VGv\n", GCPtr));
1972 /** @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. */
1973 csamFlushPage(pVM, GCPtr, false /* don't remove page! */);
1974 fInCSAMCodePageInvalidate = false;
1975 return VINF_SUCCESS;
1976}
1977
1978/**
1979 * Check if the current instruction has already been checked before
1980 *
1981 * @returns VBox status code. (trap handled or not)
1982 * @param pVM The VM to operate on.
1983 * @param pInstr Instruction pointer
1984 * @param pPage CSAM patch structure pointer
1985 */
1986bool csamIsCodeScanned(PVM pVM, RTRCPTR pInstr, PCSAMPAGE *pPage)
1987{
1988 PCSAMPAGEREC pPageRec;
1989 uint32_t offset;
1990
1991 STAM_PROFILE_START(&pVM->csam.s.StatTimeCheckAddr, a);
1992
1993 offset = pInstr & PAGE_OFFSET_MASK;
1994 pInstr = pInstr & PAGE_BASE_GC_MASK;
1995
1996 Assert(pPage);
1997
1998 if (*pPage && (*pPage)->pPageGC == pInstr)
1999 {
2000 if ((*pPage)->pBitmap == NULL || ASMBitTest((*pPage)->pBitmap, offset))
2001 {
2002 STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
2003 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
2004 return true;
2005 }
2006 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
2007 return false;
2008 }
2009
2010 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)pInstr);
2011 if (pPageRec)
2012 {
2013 if (pPage) *pPage= &pPageRec->page;
2014 if (pPageRec->page.pBitmap == NULL || ASMBitTest(pPageRec->page.pBitmap, offset))
2015 {
2016 STAM_COUNTER_ADD(&pVM->csam.s.StatNrKnownPagesHC, 1);
2017 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
2018 return true;
2019 }
2020 }
2021 else
2022 {
2023 if (pPage) *pPage = NULL;
2024 }
2025 STAM_PROFILE_STOP(&pVM->csam.s.StatTimeCheckAddr, a);
2026 return false;
2027}
2028
2029/**
2030 * Mark an instruction in a page as scanned/not scanned
2031 *
2032 * @param pVM The VM to operate on.
2033 * @param pPage Patch structure pointer
2034 * @param pInstr Instruction pointer
2035 * @param opsize Instruction size
2036 * @param fScanned Mark as scanned or not
2037 */
2038static void csamMarkCode(PVM pVM, PCSAMPAGE pPage, RTRCPTR pInstr, uint32_t opsize, bool fScanned)
2039{
2040 LogFlow(("csamMarkCodeAsScanned %VRv opsize=%d\n", pInstr, opsize));
2041 CSAMMarkPage(pVM, pInstr, fScanned);
2042
2043 /** @todo should recreate empty bitmap if !fScanned */
2044 if (pPage->pBitmap == NULL)
2045 return;
2046
2047 if (fScanned)
2048 {
2049 // retn instructions can be scanned more than once
2050 if (ASMBitTest(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK) == 0)
2051 {
2052 pPage->uSize += opsize;
2053 STAM_COUNTER_ADD(&pVM->csam.s.StatNrInstr, 1);
2054 }
2055 if (pPage->uSize >= PAGE_SIZE)
2056 {
2057 Log(("Scanned full page (%VRv) -> free bitmap\n", pInstr & PAGE_BASE_GC_MASK));
2058 MMR3HeapFree(pPage->pBitmap);
2059 pPage->pBitmap = NULL;
2060 }
2061 else
2062 ASMBitSet(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2063 }
2064 else
2065 ASMBitClear(pPage->pBitmap, pInstr & PAGE_OFFSET_MASK);
2066}
2067
2068/**
2069 * Mark an instruction in a page as scanned/not scanned
2070 *
2071 * @returns VBox status code.
2072 * @param pVM The VM to operate on.
2073 * @param pInstr Instruction pointer
2074 * @param opsize Instruction size
2075 * @param fScanned Mark as scanned or not
2076 */
2077CSAMR3DECL(int) CSAMR3MarkCode(PVM pVM, RTRCPTR pInstr, uint32_t opsize, bool fScanned)
2078{
2079 PCSAMPAGE pPage = 0;
2080
2081 Assert(!fScanned); /* other case not implemented. */
2082 Assert(!PATMIsPatchGCAddr(pVM, pInstr));
2083
2084 if (csamIsCodeScanned(pVM, pInstr, &pPage) == false)
2085 {
2086 Assert(fScanned == true); /* other case should not be possible */
2087 return VINF_SUCCESS;
2088 }
2089
2090 Log(("CSAMR3MarkCode: %VRv size=%d fScanned=%d\n", pInstr, opsize, fScanned));
2091 csamMarkCode(pVM, pPage, pInstr, opsize, fScanned);
2092 return VINF_SUCCESS;
2093}
2094
2095
2096/**
2097 * Scan and analyse code
2098 *
2099 * @returns VBox status code.
2100 * @param pVM The VM to operate on.
2101 * @param Sel selector
2102 * @param pHiddenSel The hidden selector register.
2103 * @param pInstrGC Instruction pointer
2104 */
2105CSAMR3DECL(int) CSAMR3CheckCodeEx(PVM pVM, RTSEL Sel, CPUMSELREGHID *pHiddenSel, RTRCPTR pInstrGC)
2106{
2107 if (EMIsRawRing0Enabled(pVM) == false || PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2108 {
2109 // No use
2110 return VINF_SUCCESS;
2111 }
2112
2113 if (CSAMIsEnabled(pVM))
2114 {
2115 X86EFLAGS fakeflags;
2116
2117 /* we're not in v86 mode here */
2118 fakeflags.u32 = 0;
2119
2120 bool fCode32 = SELMIsSelector32Bit(pVM, fakeflags, Sel, pHiddenSel);
2121
2122 //assuming 32 bits code for now
2123 Assert(fCode32); NOREF(fCode32);
2124
2125 pInstrGC = SELMToFlat(pVM, fakeflags, Sel, pHiddenSel, pInstrGC);
2126
2127 return CSAMR3CheckCode(pVM, pInstrGC);
2128 }
2129 return VINF_SUCCESS;
2130}
2131
2132/**
2133 * Scan and analyse code
2134 *
2135 * @returns VBox status code.
2136 * @param pVM The VM to operate on.
2137 * @param pInstrGC Instruction pointer (0:32 virtual address)
2138 */
2139CSAMR3DECL(int) CSAMR3CheckCode(PVM pVM, RTRCPTR pInstrGC)
2140{
2141 int rc;
2142 PCSAMPAGE pPage = NULL;
2143
2144 if (EMIsRawRing0Enabled(pVM) == false || PATMIsPatchGCAddr(pVM, pInstrGC) == true)
2145 {
2146 // No use
2147 return VINF_SUCCESS;
2148 }
2149
2150 if (CSAMIsEnabled(pVM))
2151 {
2152 // Cache record for PATMGCVirtToHCVirt
2153 CSAMP2GLOOKUPREC cacheRec = {0};
2154
2155 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2156 rc = csamAnalyseCallCodeStream(pVM, pInstrGC, pInstrGC, true /* 32 bits code */, CSAMR3AnalyseCallback, pPage, &cacheRec);
2157 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2158 if (rc != VINF_SUCCESS)
2159 {
2160 Log(("csamAnalyseCodeStream failed with %d\n", rc));
2161 return rc;
2162 }
2163 }
2164 return VINF_SUCCESS;
2165}
2166
2167/**
2168 * Flush dirty code pages
2169 *
2170 * @returns VBox status code.
2171 * @param pVM The VM to operate on.
2172 */
2173static int csamR3FlushDirtyPages(PVM pVM)
2174{
2175 STAM_PROFILE_START(&pVM->csam.s.StatFlushDirtyPages, a);
2176
2177 for (uint32_t i=0;i<pVM->csam.s.cDirtyPages;i++)
2178 {
2179 int rc;
2180 PCSAMPAGEREC pPageRec;
2181 RTRCPTR GCPtr = pVM->csam.s.pvDirtyBasePage[i];
2182
2183 GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2184
2185 /* Notify the recompiler that this page has been changed. */
2186 REMR3NotifyCodePageChanged(pVM, GCPtr);
2187
2188 /* Enable write protection again. (use the fault address as it might be an alias) */
2189 rc = PGMShwModifyPage(pVM, pVM->csam.s.pvDirtyFaultPage[i], 1, 0, ~(uint64_t)X86_PTE_RW);
2190 Assert(rc == VINF_SUCCESS || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT);
2191
2192 Log(("CSAMR3FlushDirtyPages: flush %VRv (modifypage rc=%Vrc)\n", pVM->csam.s.pvDirtyBasePage[i], rc));
2193
2194 pPageRec = (PCSAMPAGEREC)RTAvlPVGet(&pVM->csam.s.pPageTree, (AVLPVKEY)GCPtr);
2195 if (pPageRec && pPageRec->page.enmTag == CSAM_TAG_REM)
2196 {
2197 uint64_t fFlags;
2198
2199 rc = PGMGstGetPage(pVM, GCPtr, &fFlags, NULL);
2200 AssertMsg(VBOX_SUCCESS(rc) || rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc = %Vrc\n", rc));
2201 if ( rc == VINF_SUCCESS
2202 && (fFlags & X86_PTE_US))
2203 {
2204 /* We don't care about user pages. */
2205 csamRemovePageRecord(pVM, GCPtr);
2206 STAM_COUNTER_INC(&pVM->csam.s.StatNrUserPages);
2207 }
2208 }
2209 }
2210 pVM->csam.s.cDirtyPages = 0;
2211 STAM_PROFILE_STOP(&pVM->csam.s.StatFlushDirtyPages, a);
2212 return VINF_SUCCESS;
2213}
2214
2215/**
2216 * Flush potential new code pages
2217 *
2218 * @returns VBox status code.
2219 * @param pVM The VM to operate on.
2220 */
2221static int csamR3FlushCodePages(PVM pVM)
2222{
2223 for (uint32_t i=0;i<pVM->csam.s.cPossibleCodePages;i++)
2224 {
2225 RTRCPTR GCPtr = pVM->csam.s.pvPossibleCodePage[i];
2226
2227 GCPtr = GCPtr & PAGE_BASE_GC_MASK;
2228
2229 Log(("csamR3FlushCodePages: %VRv\n", GCPtr));
2230 PGMShwSetPage(pVM, GCPtr, 1, 0);
2231 /* Resync the page to make sure instruction fetch will fault */
2232 CSAMMarkPage(pVM, GCPtr, false);
2233 }
2234 pVM->csam.s.cPossibleCodePages = 0;
2235 return VINF_SUCCESS;
2236}
2237
2238/**
2239 * Perform any pending actions
2240 *
2241 * @returns VBox status code.
2242 * @param pVM The VM to operate on.
2243 */
2244CSAMR3DECL(int) CSAMR3DoPendingAction(PVM pVM)
2245{
2246 csamR3FlushDirtyPages(pVM);
2247 csamR3FlushCodePages(pVM);
2248
2249 VM_FF_CLEAR(pVM, VM_FF_CSAM_PENDING_ACTION);
2250 return VINF_SUCCESS;
2251}
2252
2253/**
2254 * Analyse interrupt and trap gates
2255 *
2256 * @returns VBox status code.
2257 * @param pVM The VM to operate on.
2258 * @param iGate Start gate
2259 * @param cGates Number of gates to check
2260 */
2261CSAMR3DECL(int) CSAMR3CheckGates(PVM pVM, uint32_t iGate, uint32_t cGates)
2262{
2263 uint16_t cbIDT;
2264 RTRCPTR GCPtrIDT = CPUMGetGuestIDTR(pVM, &cbIDT);
2265 uint32_t iGateEnd;
2266 uint32_t maxGates;
2267 VBOXIDTE aIDT[256];
2268 PVBOXIDTE pGuestIdte;
2269 int rc;
2270
2271 if (EMIsRawRing0Enabled(pVM) == false)
2272 {
2273 /* Enabling interrupt gates only works when raw ring 0 is enabled. */
2274 //AssertFailed();
2275 return VINF_SUCCESS;
2276 }
2277
2278 /* We only check all gates once during a session */
2279 if ( !pVM->csam.s.fGatesChecked
2280 && cGates != 256)
2281 return VINF_SUCCESS; /* too early */
2282
2283 /* We only check all gates once during a session */
2284 if ( pVM->csam.s.fGatesChecked
2285 && cGates != 1)
2286 return VINF_SUCCESS; /* ignored */
2287
2288 Assert(cGates <= 256);
2289 if (!GCPtrIDT || cGates > 256)
2290 return VERR_INVALID_PARAMETER;
2291
2292 if (cGates != 1)
2293 {
2294 pVM->csam.s.fGatesChecked = true;
2295 for (unsigned i=0;i<RT_ELEMENTS(pVM->csam.s.pvCallInstruction);i++)
2296 {
2297 RTRCPTR pHandler = pVM->csam.s.pvCallInstruction[i];
2298
2299 if (pHandler)
2300 {
2301 CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2302 PCSAMPAGE pPage = NULL;
2303
2304 Log(("CSAMCheckGates: checking previous call instruction %VRv\n", pHandler));
2305 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2306 rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2307 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2308 if (rc != VINF_SUCCESS)
2309 {
2310 Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2311 continue;
2312 }
2313 }
2314 }
2315 }
2316
2317 /* Determine valid upper boundary. */
2318 maxGates = (cbIDT+1) / sizeof(VBOXIDTE);
2319 Assert(iGate < maxGates);
2320 if (iGate > maxGates)
2321 return VERR_INVALID_PARAMETER;
2322
2323 if (iGate + cGates > maxGates)
2324 cGates = maxGates - iGate;
2325
2326 GCPtrIDT = GCPtrIDT + iGate * sizeof(VBOXIDTE);
2327 iGateEnd = iGate + cGates;
2328
2329 STAM_PROFILE_START(&pVM->csam.s.StatCheckGates, a);
2330
2331 /*
2332 * Get IDT entries.
2333 */
2334 if (PAGE_ADDRESS(GCPtrIDT) == PAGE_ADDRESS(GCPtrIDT+cGates*sizeof(VBOXIDTE)))
2335 {
2336 /* Just convert the IDT address to a HC pointer. The whole IDT fits in one page. */
2337 rc = PGMPhysGCPtr2HCPtr(pVM, GCPtrIDT, (PRTHCPTR)&pGuestIdte);
2338 if (VBOX_FAILURE(rc))
2339 {
2340 AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2341 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2342 return rc;
2343 }
2344 }
2345 else
2346 {
2347 /* Slow method when it crosses a page boundary. */
2348 rc = PGMPhysReadGCPtr(pVM, aIDT, GCPtrIDT, cGates*sizeof(VBOXIDTE));
2349 if (VBOX_FAILURE(rc))
2350 {
2351 AssertMsgRC(rc, ("Failed to read IDTE! rc=%Vrc\n", rc));
2352 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2353 return rc;
2354 }
2355 pGuestIdte = &aIDT[0];
2356 }
2357
2358 for (/*iGate*/; iGate<iGateEnd; iGate++, pGuestIdte++)
2359 {
2360 Assert(TRPMR3GetGuestTrapHandler(pVM, iGate) == TRPM_INVALID_HANDLER);
2361
2362 if ( pGuestIdte->Gen.u1Present
2363 && (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32 || pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_INT_32)
2364 && (pGuestIdte->Gen.u2DPL == 3 || pGuestIdte->Gen.u2DPL == 0)
2365 )
2366 {
2367 RTRCPTR pHandler;
2368 CSAMP2GLOOKUPREC cacheRec = {0}; /* Cache record for PATMGCVirtToHCVirt. */
2369 PCSAMPAGE pPage = NULL;
2370 X86EFLAGS fakeflags;
2371 SELMSELINFO selInfo;
2372
2373 /* we're not in v86 mode here */
2374 fakeflags.u32 = 0;
2375
2376 pHandler = VBOXIDTE_OFFSET(*pGuestIdte);
2377 pHandler = SELMToFlat(pVM, fakeflags, pGuestIdte->Gen.u16SegSel, 0, pHandler);
2378
2379 rc = SELMR3GetSelectorInfo(pVM, pGuestIdte->Gen.u16SegSel, &selInfo);
2380 if ( VBOX_FAILURE(rc)
2381 || selInfo.GCPtrBase != 0
2382 || selInfo.cbLimit != ~0U
2383 )
2384 {
2385 /* Refuse to patch a handler whose idt cs selector isn't wide open. */
2386 Log(("CSAMCheckGates: check gate %d failed due to rc %Vrc GCPtrBase=%VRv limit=%x\n", iGate, rc, selInfo.GCPtrBase, selInfo.cbLimit));
2387 continue;
2388 }
2389
2390
2391 if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2392 {
2393 Log(("CSAMCheckGates: check trap gate %d at %04X:%08X (flat %VRv)\n", iGate, pGuestIdte->Gen.u16SegSel, VBOXIDTE_OFFSET(*pGuestIdte), pHandler));
2394 }
2395 else
2396 {
2397 Log(("CSAMCheckGates: check interrupt gate %d at %04X:%08X (flat %VRv)\n", iGate, pGuestIdte->Gen.u16SegSel, VBOXIDTE_OFFSET(*pGuestIdte), pHandler));
2398 }
2399
2400 STAM_PROFILE_START(&pVM->csam.s.StatTime, a);
2401 rc = csamAnalyseCodeStream(pVM, pHandler, pHandler, true, CSAMR3AnalyseCallback, pPage, &cacheRec);
2402 STAM_PROFILE_STOP(&pVM->csam.s.StatTime, a);
2403 if (rc != VINF_SUCCESS)
2404 {
2405 Log(("CSAMCheckGates: csamAnalyseCodeStream failed with %d\n", rc));
2406 continue;
2407 }
2408 /* OpenBSD guest specific patch test. */
2409 if (iGate >= 0x20)
2410 {
2411 PCPUMCTX pCtx;
2412 DISCPUSTATE cpu;
2413 RTGCUINTPTR32 aOpenBsdPushCSOffset[3] = {0x03, /* OpenBSD 3.7 & 3.8 */
2414 0x2B, /* OpenBSD 4.0 installation ISO */
2415 0x2F}; /* OpenBSD 4.0 after install */
2416
2417 rc = CPUMQueryGuestCtxPtr(pVM, &pCtx);
2418 AssertRC(rc); /* can't fail */
2419
2420 for (unsigned i=0;i<ELEMENTS(aOpenBsdPushCSOffset);i++)
2421 {
2422 rc = CPUMR3DisasmInstrCPU(pVM, pCtx, pHandler - aOpenBsdPushCSOffset[i], &cpu, NULL);
2423 if ( rc == VINF_SUCCESS
2424 && cpu.pCurInstr->opcode == OP_PUSH
2425 && cpu.pCurInstr->param1 == OP_PARM_REG_CS)
2426 {
2427 rc = PATMR3InstallPatch(pVM, pHandler - aOpenBsdPushCSOffset[i], PATMFL_CODE32 | PATMFL_GUEST_SPECIFIC);
2428 if (VBOX_SUCCESS(rc))
2429 Log(("Installed OpenBSD interrupt handler prefix instruction (push cs) patch\n"));
2430 }
2431 }
2432 }
2433
2434 /* Trap gates and certain interrupt gates. */
2435 uint32_t fPatchFlags = PATMFL_CODE32 | PATMFL_IDTHANDLER;
2436
2437 if (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32)
2438 fPatchFlags |= PATMFL_TRAPHANDLER;
2439 else
2440 fPatchFlags |= PATMFL_INTHANDLER;
2441
2442 switch (iGate) {
2443 case 8:
2444 case 10:
2445 case 11:
2446 case 12:
2447 case 13:
2448 case 14:
2449 case 17:
2450 fPatchFlags |= PATMFL_TRAPHANDLER_WITH_ERRORCODE;
2451 break;
2452 default:
2453 /* No error code. */
2454 break;
2455 }
2456
2457 Log(("Installing %s gate handler for 0x%X at %VRv\n", (pGuestIdte->Gen.u5Type2 == VBOX_IDTE_TYPE2_TRAP_32) ? "trap" : "intr", iGate, pHandler));
2458
2459 rc = PATMR3InstallPatch(pVM, pHandler, fPatchFlags);
2460 if (VBOX_SUCCESS(rc) || rc == VERR_PATM_ALREADY_PATCHED)
2461 {
2462 Log(("Gate handler 0x%X is SAFE!\n", iGate));
2463
2464 RTRCPTR pNewHandlerGC = PATMR3QueryPatchGCPtr(pVM, pHandler);
2465 if (pNewHandlerGC)
2466 {
2467 rc = TRPMR3SetGuestTrapHandler(pVM, iGate, pNewHandlerGC);
2468 if (VBOX_FAILURE(rc))
2469 Log(("TRPMR3SetGuestTrapHandler %d failed with %Vrc\n", iGate, rc));
2470 }
2471 }
2472 }
2473 } /* for */
2474 STAM_PROFILE_STOP(&pVM->csam.s.StatCheckGates, a);
2475 return VINF_SUCCESS;
2476}
2477
2478/**
2479 * Record previous call instruction addresses
2480 *
2481 * @returns VBox status code.
2482 * @param pVM The VM to operate on.
2483 * @param GCPtrCall Call address
2484 */
2485CSAMR3DECL(int) CSAMR3RecordCallAddress(PVM pVM, RTRCPTR GCPtrCall)
2486{
2487 for (unsigned i=0;i<RT_ELEMENTS(pVM->csam.s.pvCallInstruction);i++)
2488 {
2489 if (pVM->csam.s.pvCallInstruction[i] == GCPtrCall)
2490 return VINF_SUCCESS;
2491 }
2492
2493 Log(("CSAMR3RecordCallAddress %VRv\n", GCPtrCall));
2494
2495 pVM->csam.s.pvCallInstruction[pVM->csam.s.iCallInstruction++] = GCPtrCall;
2496 if (pVM->csam.s.iCallInstruction >= RT_ELEMENTS(pVM->csam.s.pvCallInstruction))
2497 pVM->csam.s.iCallInstruction = 0;
2498
2499 return VINF_SUCCESS;
2500}
2501
2502
2503/**
2504 * Query CSAM state (enabled/disabled)
2505 *
2506 * @returns 0 - disabled, 1 - enabled
2507 * @param pVM The VM to operate on.
2508 */
2509CSAMR3DECL(int) CSAMR3IsEnabled(PVM pVM)
2510{
2511 return pVM->fCSAMEnabled;
2512}
2513
2514#ifdef VBOX_WITH_DEBUGGER
2515/**
2516 * The '.csamoff' command.
2517 *
2518 * @returns VBox status.
2519 * @param pCmd Pointer to the command descriptor (as registered).
2520 * @param pCmdHlp Pointer to command helper functions.
2521 * @param pVM Pointer to the current VM (if any).
2522 * @param paArgs Pointer to (readonly) array of arguments.
2523 * @param cArgs Number of arguments in the array.
2524 */
2525static DECLCALLBACK(int) csamr3CmdOff(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2526{
2527 /*
2528 * Validate input.
2529 */
2530 if (!pVM)
2531 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2532
2533 CSAMDisableScanning(pVM);
2534 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning disabled\n");
2535}
2536
2537/**
2538 * The '.csamon' command.
2539 *
2540 * @returns VBox status.
2541 * @param pCmd Pointer to the command descriptor (as registered).
2542 * @param pCmdHlp Pointer to command helper functions.
2543 * @param pVM Pointer to the current VM (if any).
2544 * @param paArgs Pointer to (readonly) array of arguments.
2545 * @param cArgs Number of arguments in the array.
2546 */
2547static DECLCALLBACK(int) csamr3CmdOn(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PVM pVM, PCDBGCVAR paArgs, unsigned cArgs, PDBGCVAR pResult)
2548{
2549 /*
2550 * Validate input.
2551 */
2552 if (!pVM)
2553 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "error: The command requires VM to be selected.\n");
2554
2555 CSAMEnableScanning(pVM);
2556 return pCmdHlp->pfnPrintf(pCmdHlp, NULL, "CSAM Scanning enabled\n");
2557}
2558#endif
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