/* $Id: SELM.cpp 347 2007-01-26 09:36:22Z vboxsync $ */ /** @file * SELM - The Selector manager. */ /* * Copyright (C) 2006 InnoTek Systemberatung GmbH * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License as published by the Free Software Foundation, * in version 2 as it comes in the "COPYING" file of the VirtualBox OSE * distribution. VirtualBox OSE is distributed in the hope that it will * be useful, but WITHOUT ANY WARRANTY of any kind. * * If you received this file as part of a commercial VirtualBox * distribution, then only the terms of your commercial VirtualBox * license agreement apply instead of the previous paragraph. */ /******************************************************************************* * Header Files * *******************************************************************************/ #define LOG_GROUP LOG_GROUP_SELM #include #include #include #include #include #include #include #include #include "SELMInternal.h" #include #include #include #include #include #include #include #include #include #include "x86context.h" /** * Enable or disable tracking of Guest's GDT/LDT/TSS. * @{ */ #define SELM_TRACK_GUEST_GDT_CHANGES #define SELM_TRACK_GUEST_LDT_CHANGES #define SELM_TRACK_GUEST_TSS_CHANGES /** @} */ /** * Enable or disable tracking of Shadow GDT/LDT/TSS. * @{ */ #define SELM_TRACK_SHADOW_GDT_CHANGES #define SELM_TRACK_SHADOW_LDT_CHANGES #define SELM_TRACK_SHADOW_TSS_CHANGES /** @} */ /** SELM saved state version. */ #define SELM_SAVED_STATE_VERSION 5 /******************************************************************************* * Internal Functions * *******************************************************************************/ static DECLCALLBACK(int) selmR3Save(PVM pVM, PSSMHANDLE pSSM); static DECLCALLBACK(int) selmR3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version); static DECLCALLBACK(void) selmR3InfoGdt(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs); static DECLCALLBACK(void) selmR3InfoGdtGuest(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs); static DECLCALLBACK(void) selmR3InfoLdt(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs); static DECLCALLBACK(void) selmR3InfoLdtGuest(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs); //static DECLCALLBACK(void) selmR3InfoTss(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs); //static DECLCALLBACK(void) selmR3InfoTssGuest(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs); static DECLCALLBACK(int) selmGuestGDTWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPhys, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser); static DECLCALLBACK(int) selmGuestLDTWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPhys, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser); static DECLCALLBACK(int) selmGuestTSSWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPhys, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser); /** * Initializes the SELM. * * @returns VBox status code. * @param pVM The VM to operate on. */ SELMR3DECL(int) SELMR3Init(PVM pVM) { LogFlow(("SELMR3Init\n")); /* * Assert alignment and sizes. */ AssertRelease(!(RT_OFFSETOF(VM, selm.s) & 31)); AssertRelease(!(RT_OFFSETOF(VM, selm.s.Tss) & 15)); AssertRelease(sizeof(pVM->selm.s) <= sizeof(pVM->selm.padding)); /* * Init the structure. */ pVM->selm.s.offVM = RT_OFFSETOF(VM, selm); pVM->selm.s.SelCS = (SELM_GDT_ELEMENTS - 0x1) << 3; pVM->selm.s.SelDS = (SELM_GDT_ELEMENTS - 0x2) << 3; pVM->selm.s.SelCS64 = (SELM_GDT_ELEMENTS - 0x3) << 3; pVM->selm.s.SelTSS = (SELM_GDT_ELEMENTS - 0x4) << 3; pVM->selm.s.SelTSSTrap08 = (SELM_GDT_ELEMENTS - 0x5) << 3; /* * Allocate GDT table. */ int rc = MMR3HyperAllocOnceNoRel(pVM, sizeof(pVM->selm.s.paGdtHC[0]) * SELM_GDT_ELEMENTS, PAGE_SIZE, MM_TAG_SELM, (void **)&pVM->selm.s.paGdtHC); AssertRCReturn(rc, rc); /* * Allocate LDT area. */ rc = MMR3HyperAllocOnceNoRel(pVM, _64K + PAGE_SIZE, PAGE_SIZE, MM_TAG_SELM, &pVM->selm.s.HCPtrLdt); AssertRCReturn(rc, rc); /* * Init Guest's and Shadow GDT, LDT, TSS changes control variables. */ pVM->selm.s.cbEffGuestGdtLimit = 0; pVM->selm.s.GuestGdtr.pGdt = ~0; pVM->selm.s.GCPtrGuestLdt = ~0; pVM->selm.s.GCPtrGuestTss = ~0; pVM->selm.s.paGdtGC = 0; pVM->selm.s.GCPtrLdt = ~0; pVM->selm.s.GCPtrTss = ~0; pVM->selm.s.GCSelTss = ~0; pVM->selm.s.fDisableMonitoring = false; pVM->selm.s.fSyncTSSRing0Stack = false; /* * Register the saved state data unit. */ rc = SSMR3RegisterInternal(pVM, "selm", 1, SELM_SAVED_STATE_VERSION, sizeof(SELM), NULL, selmR3Save, NULL, NULL, selmR3Load, NULL); if (VBOX_FAILURE(rc)) return rc; /* * Statistics. */ STAM_REG(pVM, &pVM->selm.s.StatGCWriteGuestGDTHandled, STAMTYPE_COUNTER, "/SELM/GC/Write/Guest/GDTInt", STAMUNIT_OCCURENCES, "The number of handled writes to the Guest GDT."); STAM_REG(pVM, &pVM->selm.s.StatGCWriteGuestGDTUnhandled, STAMTYPE_COUNTER, "/SELM/GC/Write/Guest/GDTEmu", STAMUNIT_OCCURENCES, "The number of unhandled writes to the Guest GDT."); STAM_REG(pVM, &pVM->selm.s.StatGCWriteGuestLDT, STAMTYPE_COUNTER, "/SELM/GC/Write/Guest/LDT", STAMUNIT_OCCURENCES, "The number of writes to the Guest LDT was detected."); STAM_REG(pVM, &pVM->selm.s.StatGCWriteGuestTSSHandled, STAMTYPE_COUNTER, "/SELM/GC/Write/Guest/TSSInt", STAMUNIT_OCCURENCES, "The number of handled writes to the Guest TSS."); STAM_REG(pVM, &pVM->selm.s.StatGCWriteGuestTSSHandledChanged,STAMTYPE_COUNTER, "/SELM/GC/Write/Guest/TSSIntChg", STAMUNIT_OCCURENCES, "The number of handled writes to the Guest TSS where the R0 stack changed."); STAM_REG(pVM, &pVM->selm.s.StatGCWriteGuestTSSUnhandled, STAMTYPE_COUNTER, "/SELM/GC/Write/Guest/TSSEmu", STAMUNIT_OCCURENCES, "The number of unhandled writes to the Guest TSS."); STAM_REG(pVM, &pVM->selm.s.StatTSSSync, STAMTYPE_PROFILE, "/PROF/SELM/TSSSync", STAMUNIT_TICKS_PER_CALL, "Profiling of the SELMR3SyncTSS() body."); STAM_REG(pVM, &pVM->selm.s.StatUpdateFromCPUM, STAMTYPE_PROFILE, "/PROF/SELM/UpdateFromCPUM", STAMUNIT_TICKS_PER_CALL, "Profiling of the SELMR3UpdateFromCPUM() body."); /* * Default action when entering raw mode for the first time */ VM_FF_SET(pVM, VM_FF_SELM_SYNC_TSS); VM_FF_SET(pVM, VM_FF_SELM_SYNC_GDT); VM_FF_SET(pVM, VM_FF_SELM_SYNC_LDT); /* * Register info handlers. */ DBGFR3InfoRegisterInternal(pVM, "gdt", "Displays the shadow GDT. No arguments.", &selmR3InfoGdt); DBGFR3InfoRegisterInternal(pVM, "gdtguest", "Displays the guest GDT. No arguments.", &selmR3InfoGdtGuest); DBGFR3InfoRegisterInternal(pVM, "ldt", "Displays the shadow LDT. No arguments.", &selmR3InfoLdt); DBGFR3InfoRegisterInternal(pVM, "ldtguest", "Displays the guest LDT. No arguments.", &selmR3InfoLdtGuest); //DBGFR3InfoRegisterInternal(pVM, "tss", "Displays the shadow TSS. No arguments.", &selmR3InfoTss); //DBGFR3InfoRegisterInternal(pVM, "tssguest", "Displays the guest TSS. No arguments.", &selmR3InfoTssGuest); return rc; } /** * Finalizes HMA page attributes. * * @returns VBox status code. * @param pVM The VM handle. */ SELMR3DECL(int) SELMR3InitFinalize(PVM pVM) { /* * Make Double Fault work with WP enabled? * * The double fault is a task switch and thus requires write access to the GDT of the TSS * (to set it busy), to the old TSS (to store state), and to the Trap 8 TSS for the back link. * * Since we in enabling write access to these pages make ourself vulnerable to attacks, * it is not possible to do this by default. */ bool f; int rc = CFGMR3QueryBool(CFGMR3GetRoot(pVM), "DoubleFault", &f); #if !defined(DEBUG_bird) if (VBOX_SUCCESS(rc) && f) #endif { PVBOXDESC paGdt = pVM->selm.s.paGdtHC; rc = PGMMapSetPage(pVM, MMHyperHC2GC(pVM, &paGdt[pVM->selm.s.SelTSSTrap08 >> 3]), sizeof(paGdt[0]), X86_PTE_RW | X86_PTE_P | X86_PTE_A | X86_PTE_D); AssertRC(rc); rc = PGMMapSetPage(pVM, MMHyperHC2GC(pVM, &paGdt[pVM->selm.s.SelTSS >> 3]), sizeof(paGdt[0]), X86_PTE_RW | X86_PTE_P | X86_PTE_A | X86_PTE_D); AssertRC(rc); rc = PGMMapSetPage(pVM, VM_GUEST_ADDR(pVM, &pVM->selm.s.Tss), sizeof(pVM->selm.s.Tss), X86_PTE_RW | X86_PTE_P | X86_PTE_A | X86_PTE_D); AssertRC(rc); rc = PGMMapSetPage(pVM, VM_GUEST_ADDR(pVM, &pVM->selm.s.TssTrap08), sizeof(pVM->selm.s.TssTrap08), X86_PTE_RW | X86_PTE_P | X86_PTE_A | X86_PTE_D); AssertRC(rc); } return VINF_SUCCESS; } /** * Applies relocations to data and code managed by this * component. This function will be called at init and * whenever the VMM need to relocate it self inside the GC. * * @param pVM The VM. */ SELMR3DECL(void) SELMR3Relocate(PVM pVM) { LogFlow(("SELMR3Relocate\n")); PVBOXDESC paGdt = pVM->selm.s.paGdtHC; /* * Update GDTR and selector. */ CPUMSetHyperGDTR(pVM, MMHyperHC2GC(pVM, paGdt), SELM_GDT_ELEMENTS * sizeof(paGdt[0]) - 1); /** @todo selector relocations should be a seperate operation? */ CPUMSetHyperCS(pVM, pVM->selm.s.SelCS); CPUMSetHyperDS(pVM, pVM->selm.s.SelDS); CPUMSetHyperES(pVM, pVM->selm.s.SelDS); CPUMSetHyperSS(pVM, pVM->selm.s.SelDS); CPUMSetHyperTR(pVM, pVM->selm.s.SelTSS); /* * Set up global code and data descriptors for use in the guest context. * Both are wide open (base 0, limit 4GB) */ PVBOXDESC pDesc = &paGdt[pVM->selm.s.SelCS >> 3]; pDesc->Gen.u16LimitLow = 0xffff; pDesc->Gen.u4LimitHigh = 0xf; pDesc->Gen.u16BaseLow = 0; pDesc->Gen.u8BaseHigh1 = 0; pDesc->Gen.u8BaseHigh2 = 0; pDesc->Gen.u4Type = X86_SELTYPE_MEM_EXECUTEREAD_ACC; pDesc->Gen.u1DescType = 1; /* not system, but code/data */ pDesc->Gen.u2Dpl = 0; /* supervisor */ pDesc->Gen.u1Present = 1; pDesc->Gen.u1Available = 0; pDesc->Gen.u1Reserved = 0; pDesc->Gen.u1DefBig = 1; /* def 32 bit */ pDesc->Gen.u1Granularity = 1; /* 4KB limit */ /* data */ pDesc = &paGdt[pVM->selm.s.SelDS >> 3]; pDesc->Gen.u16LimitLow = 0xffff; pDesc->Gen.u4LimitHigh = 0xf; pDesc->Gen.u16BaseLow = 0; pDesc->Gen.u8BaseHigh1 = 0; pDesc->Gen.u8BaseHigh2 = 0; pDesc->Gen.u4Type = X86_SELTYPE_MEM_READWRITE_ACC; pDesc->Gen.u1DescType = 1; /* not system, but code/data */ pDesc->Gen.u2Dpl = 0; /* supervisor */ pDesc->Gen.u1Present = 1; pDesc->Gen.u1Available = 0; pDesc->Gen.u1Reserved = 0; pDesc->Gen.u1DefBig = 1; /* big */ pDesc->Gen.u1Granularity = 1; /* 4KB limit */ /* 64-bit mode code (& data?) */ pDesc = &paGdt[pVM->selm.s.SelCS64 >> 3]; pDesc->Gen.u16LimitLow = 0xffff; pDesc->Gen.u4LimitHigh = 0xf; pDesc->Gen.u16BaseLow = 0; pDesc->Gen.u8BaseHigh1 = 0; pDesc->Gen.u8BaseHigh2 = 0; pDesc->Gen.u4Type = X86_SELTYPE_MEM_EXECUTEREAD_ACC; pDesc->Gen.u1DescType = 1; /* not system, but code/data */ pDesc->Gen.u2Dpl = 0; /* supervisor */ pDesc->Gen.u1Present = 1; pDesc->Gen.u1Available = 0; pDesc->Gen.u1Reserved = 1; /* The Long (L) attribute bit. */ pDesc->Gen.u1DefBig = 0; /* With L=1 this must be 0. */ pDesc->Gen.u1Granularity = 1; /* 4KB limit */ /* * TSS descriptor */ pDesc = &paGdt[pVM->selm.s.SelTSS >> 3]; RTGCPTR pGCTSS = VM_GUEST_ADDR(pVM, &pVM->selm.s.Tss); pDesc->Gen.u16BaseLow = RT_LOWORD(pGCTSS); pDesc->Gen.u8BaseHigh1 = RT_BYTE3(pGCTSS); pDesc->Gen.u8BaseHigh2 = RT_BYTE4(pGCTSS); pDesc->Gen.u16LimitLow = sizeof(VBOXTSS) - 1; pDesc->Gen.u4LimitHigh = 0; pDesc->Gen.u4Type = X86_SELTYPE_SYS_386_TSS_AVAIL; pDesc->Gen.u1DescType = 0; /* system */ pDesc->Gen.u2Dpl = 0; /* supervisor */ pDesc->Gen.u1Present = 1; pDesc->Gen.u1Available = 0; pDesc->Gen.u1Reserved = 0; pDesc->Gen.u1DefBig = 0; pDesc->Gen.u1Granularity = 0; /* byte limit */ /* * TSS descriptor for trap 08 */ pDesc = &paGdt[pVM->selm.s.SelTSSTrap08 >> 3]; pDesc->Gen.u16LimitLow = sizeof(VBOXTSS) - 1; pDesc->Gen.u4LimitHigh = 0; pGCTSS = VM_GUEST_ADDR(pVM, &pVM->selm.s.TssTrap08); pDesc->Gen.u16BaseLow = RT_LOWORD(pGCTSS); pDesc->Gen.u8BaseHigh1 = RT_BYTE3(pGCTSS); pDesc->Gen.u8BaseHigh2 = RT_BYTE4(pGCTSS); pDesc->Gen.u4Type = X86_SELTYPE_SYS_386_TSS_AVAIL; pDesc->Gen.u1DescType = 0; /* system */ pDesc->Gen.u2Dpl = 0; /* supervisor */ pDesc->Gen.u1Present = 1; pDesc->Gen.u1Available = 0; pDesc->Gen.u1Reserved = 0; pDesc->Gen.u1DefBig = 0; pDesc->Gen.u1Granularity = 0; /* byte limit */ /** @todo SELM must be called when any of the CR3s changes during a cpu mode change. */ /** @todo PGM knows the proper CR3 values these days, not CPUM. */ /* * Update the TSSes. */ /* Current TSS */ pVM->selm.s.Tss.cr3 = PGMGetHyperCR3(pVM); pVM->selm.s.Tss.ss0 = pVM->selm.s.SelDS; pVM->selm.s.Tss.esp0 = VMMGetStackGC(pVM); pVM->selm.s.Tss.cs = pVM->selm.s.SelCS; pVM->selm.s.Tss.ds = pVM->selm.s.SelDS; pVM->selm.s.Tss.es = pVM->selm.s.SelDS; pVM->selm.s.Tss.offIoBitmap = sizeof(VBOXTSS); /* trap 08 */ pVM->selm.s.TssTrap08.cr3 = PGMGetInterGCCR3(pVM); /* this should give use better survival chances. */ pVM->selm.s.TssTrap08.ss0 = pVM->selm.s.SelDS; pVM->selm.s.TssTrap08.ss = pVM->selm.s.SelDS; pVM->selm.s.TssTrap08.esp0 = VMMGetStackGC(pVM) - PAGE_SIZE / 2; /* upper half can be analysed this way. */ pVM->selm.s.TssTrap08.esp = pVM->selm.s.TssTrap08.esp0; pVM->selm.s.TssTrap08.ebp = pVM->selm.s.TssTrap08.esp0; pVM->selm.s.TssTrap08.cs = pVM->selm.s.SelCS; pVM->selm.s.TssTrap08.ds = pVM->selm.s.SelDS; pVM->selm.s.TssTrap08.es = pVM->selm.s.SelDS; pVM->selm.s.TssTrap08.fs = 0; pVM->selm.s.TssTrap08.gs = 0; pVM->selm.s.TssTrap08.selLdt = 0; pVM->selm.s.TssTrap08.eflags = 0x2; /* all cleared */ pVM->selm.s.TssTrap08.ecx = VM_GUEST_ADDR(pVM, &pVM->selm.s.Tss); /* setup ecx to normal Hypervisor TSS address. */ pVM->selm.s.TssTrap08.edi = pVM->selm.s.TssTrap08.ecx; pVM->selm.s.TssTrap08.eax = pVM->selm.s.TssTrap08.ecx; pVM->selm.s.TssTrap08.edx = VM_GUEST_ADDR(pVM, pVM); /* setup edx VM address. */ pVM->selm.s.TssTrap08.edi = pVM->selm.s.TssTrap08.edx; pVM->selm.s.TssTrap08.ebx = pVM->selm.s.TssTrap08.edx; pVM->selm.s.TssTrap08.offIoBitmap = sizeof(VBOXTSS); /* TRPM will be updating the eip */ if (!pVM->selm.s.fDisableMonitoring) { /* * Update shadow GDT/LDT/TSS write access handlers. */ int rc; #ifdef SELM_TRACK_SHADOW_GDT_CHANGES if (pVM->selm.s.paGdtGC != 0) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.paGdtGC); AssertRC(rc); } pVM->selm.s.paGdtGC = MMHyperHC2GC(pVM, paGdt); rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_HYPERVISOR, pVM->selm.s.paGdtGC, pVM->selm.s.paGdtGC + SELM_GDT_ELEMENTS * sizeof(paGdt[0]) - 1, 0, 0, "selmgcShadowGDTWriteHandler", 0, "Shadow GDT write access handler"); AssertRC(rc); #endif #ifdef SELM_TRACK_SHADOW_TSS_CHANGES if (pVM->selm.s.GCPtrTss != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrTss); AssertRC(rc); } pVM->selm.s.GCPtrTss = VM_GUEST_ADDR(pVM, &pVM->selm.s.Tss); rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_HYPERVISOR, pVM->selm.s.GCPtrTss, pVM->selm.s.GCPtrTss + sizeof(pVM->selm.s.Tss) - 1, 0, 0, "selmgcShadowTSSWriteHandler", 0, "Shadow TSS write access handler"); AssertRC(rc); #endif /* * Update the GC LDT region handler and address. */ #ifdef SELM_TRACK_SHADOW_LDT_CHANGES if (pVM->selm.s.GCPtrLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrLdt); AssertRC(rc); } #endif pVM->selm.s.GCPtrLdt = MMHyperHC2GC(pVM, pVM->selm.s.HCPtrLdt); #ifdef SELM_TRACK_SHADOW_LDT_CHANGES rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_HYPERVISOR, pVM->selm.s.GCPtrLdt, pVM->selm.s.GCPtrLdt + _64K + PAGE_SIZE - 1, 0, 0, "selmgcShadowLDTWriteHandler", 0, "Shadow LDT write access handler"); AssertRC(rc); #endif } } /** * Notification callback which is called whenever there is a chance that a CR3 * value might have changed. * This is called by PGM. * * @param pVM The VM handle */ SELMR3DECL(void) SELMR3PagingModeChanged(PVM pVM) { pVM->selm.s.Tss.cr3 = PGMGetHyperCR3(pVM); pVM->selm.s.TssTrap08.cr3 = PGMGetInterGCCR3(pVM); } /** * Terminates the SELM. * * Termination means cleaning up and freeing all resources, * the VM it self is at this point powered off or suspended. * * @returns VBox status code. * @param pVM The VM to operate on. */ SELMR3DECL(int) SELMR3Term(PVM pVM) { return 0; } /** * The VM is being reset. * * For the SELM component this means that any GDT/LDT/TSS monitors * needs to be removed. * * @param pVM VM handle. */ SELMR3DECL(void) SELMR3Reset(PVM pVM) { LogFlow(("SELMR3Reset:\n")); VM_ASSERT_EMT(pVM); /* * Uninstall guest GDT/LDT/TSS write access handlers. */ int rc; #ifdef SELM_TRACK_GUEST_GDT_CHANGES if (pVM->selm.s.GuestGdtr.pGdt != ~0U && pVM->selm.s.fGDTRangeRegistered) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GuestGdtr.pGdt); AssertRC(rc); pVM->selm.s.GuestGdtr.pGdt = ~0U; pVM->selm.s.GuestGdtr.cbGdt = 0; } pVM->selm.s.fGDTRangeRegistered = false; #endif #ifdef SELM_TRACK_GUEST_LDT_CHANGES if (pVM->selm.s.GCPtrGuestLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestLdt); AssertRC(rc); pVM->selm.s.GCPtrGuestLdt = ~0U; } #endif #ifdef SELM_TRACK_GUEST_TSS_CHANGES if (pVM->selm.s.GCPtrGuestTss != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestTss); AssertRC(rc); pVM->selm.s.GCPtrGuestTss = ~0U; pVM->selm.s.GCSelTss = ~0; } #endif /* * Re-initialize other members. */ pVM->selm.s.cbLdtLimit = 0; pVM->selm.s.offLdtHyper = 0; pVM->selm.s.cbMonitoredGuestTss = 0; pVM->selm.s.fSyncTSSRing0Stack = false; /* * Default action when entering raw mode for the first time */ VM_FF_SET(pVM, VM_FF_SELM_SYNC_TSS); VM_FF_SET(pVM, VM_FF_SELM_SYNC_GDT); VM_FF_SET(pVM, VM_FF_SELM_SYNC_LDT); } /** * Disable GDT/LDT/TSS monitoring and syncing * * @param pVM The VM to operate on. */ SELMR3DECL(void) SELMR3DisableMonitoring(PVM pVM) { /* * Uninstall guest GDT/LDT/TSS write access handlers. */ int rc; #ifdef SELM_TRACK_GUEST_GDT_CHANGES if (pVM->selm.s.GuestGdtr.pGdt != ~0U && pVM->selm.s.fGDTRangeRegistered) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GuestGdtr.pGdt); AssertRC(rc); pVM->selm.s.GuestGdtr.pGdt = ~0U; pVM->selm.s.GuestGdtr.cbGdt = 0; } pVM->selm.s.fGDTRangeRegistered = false; #endif #ifdef SELM_TRACK_GUEST_LDT_CHANGES if (pVM->selm.s.GCPtrGuestLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestLdt); AssertRC(rc); pVM->selm.s.GCPtrGuestLdt = ~0U; } #endif #ifdef SELM_TRACK_GUEST_TSS_CHANGES if (pVM->selm.s.GCPtrGuestTss != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestTss); AssertRC(rc); pVM->selm.s.GCPtrGuestTss = ~0U; pVM->selm.s.GCSelTss = ~0; } #endif /* * Unregister shadow GDT/LDT/TSS write access handlers. */ #ifdef SELM_TRACK_SHADOW_GDT_CHANGES if (pVM->selm.s.paGdtGC != 0) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.paGdtGC); AssertRC(rc); pVM->selm.s.paGdtGC = 0; } #endif #ifdef SELM_TRACK_SHADOW_TSS_CHANGES if (pVM->selm.s.GCPtrTss != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrTss); AssertRC(rc); pVM->selm.s.GCPtrTss = ~0U; } #endif #ifdef SELM_TRACK_SHADOW_LDT_CHANGES if (pVM->selm.s.GCPtrLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrLdt); AssertRC(rc); pVM->selm.s.GCPtrLdt = ~0U; } #endif VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_TSS); VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_GDT); VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_LDT); pVM->selm.s.fDisableMonitoring = true; } /** * Execute state save operation. * * @returns VBox status code. * @param pVM VM Handle. * @param pSSM SSM operation handle. */ static DECLCALLBACK(int) selmR3Save(PVM pVM, PSSMHANDLE pSSM) { LogFlow(("selmR3Save:\n")); /* * Save the basic bits - fortunately all the other things can be resynced on load. */ PSELM pSelm = &pVM->selm.s; SSMR3PutBool(pSSM, pSelm->fDisableMonitoring); SSMR3PutBool(pSSM, pSelm->fSyncTSSRing0Stack); SSMR3PutSel(pSSM, pSelm->SelCS); SSMR3PutSel(pSSM, pSelm->SelDS); SSMR3PutSel(pSSM, pSelm->SelCS64); SSMR3PutSel(pSSM, pSelm->SelCS64); //reserved for DS64. SSMR3PutSel(pSSM, pSelm->SelTSS); return SSMR3PutSel(pSSM, pSelm->SelTSSTrap08); } /** * Execute state load operation. * * @returns VBox status code. * @param pVM VM Handle. * @param pSSM SSM operation handle. * @param u32Version Data layout version. */ static DECLCALLBACK(int) selmR3Load(PVM pVM, PSSMHANDLE pSSM, uint32_t u32Version) { LogFlow(("selmR3Load:\n")); /* * Validate version. */ if (u32Version != SELM_SAVED_STATE_VERSION) { Log(("selmR3Load: Invalid version u32Version=%d!\n", u32Version)); return VERR_SSM_UNSUPPORTED_DATA_UNIT_VERSION; } /* * Do a reset. */ SELMR3Reset(pVM); /* Get the monitoring flag. */ SSMR3GetBool(pSSM, &pVM->selm.s.fDisableMonitoring); /* Get the TSS state flag. */ SSMR3GetBool(pSSM, &pVM->selm.s.fSyncTSSRing0Stack); /* * Get the selectors. */ RTSEL SelCS; SSMR3GetSel(pSSM, &SelCS); RTSEL SelDS; SSMR3GetSel(pSSM, &SelDS); RTSEL SelCS64; SSMR3GetSel(pSSM, &SelCS64); RTSEL SelDS64; SSMR3GetSel(pSSM, &SelDS64); RTSEL SelTSS; SSMR3GetSel(pSSM, &SelTSS); RTSEL SelTSSTrap08; SSMR3GetSel(pSSM, &SelTSSTrap08); if (u32Version == 1) { RTSEL SelTSSTrap0a; int rc = SSMR3GetSel(pSSM, &SelTSSTrap0a); if (VBOX_FAILURE(rc)) return rc; } /* Check that no selectors have be relocated. */ PSELM pSelm = &pVM->selm.s; if ( SelCS != pSelm->SelCS || SelDS != pSelm->SelDS || SelCS64 != pSelm->SelCS64 || SelDS64 != pSelm->SelCS64 || SelTSS != pSelm->SelTSS || SelTSSTrap08 != pSelm->SelTSSTrap08) { AssertMsgFailed(("Some selector have been relocated - this cannot happen!\n")); return VERR_SSM_DATA_UNIT_FORMAT_CHANGED; } /* * Flag everything for resync. */ VM_FF_SET(pVM, VM_FF_SELM_SYNC_GDT); VM_FF_SET(pVM, VM_FF_SELM_SYNC_LDT); VM_FF_SET(pVM, VM_FF_SELM_SYNC_TSS); return VINF_SUCCESS; } /** * Sets up the virtualization of a guest GDT. * * @returns VBox status code. * @param pVM The VM to operate on. * @param paGDTEs Pointer to GDT array. * @param cGDTEs Number of entries in the GDT array. */ SELMR3DECL(int) SELMR3GdtSetup(PVM pVM, PCVBOXDESC paGDTEs, unsigned cGDTEs) { AssertMsg(cGDTEs <= (unsigned)(pVM->selm.s.SelTSSTrap08 >> 3), ("Oops! the loaded GDT is as large as our.. we assume no clashes!!!\n")); /* * Enumerate the array. */ PCVBOXDESC pGDTESrc = paGDTEs; PVBOXDESC pGDTEDst = pVM->selm.s.paGdtHC; for (unsigned iGDT = 0; iGDT < cGDTEs; iGDT++, pGDTEDst++, pGDTESrc++) { /* ASSUME no clashes for now - lazy bird!!! */ if (pGDTESrc->Gen.u1Present) { pGDTEDst->Gen = pGDTESrc->Gen; /* mark non ring-3 selectors as not present. */ if (pGDTEDst->Gen.u2Dpl != 3) pGDTEDst->Gen.u1Present = 0; } else { /* zero it. */ pGDTEDst->au32[0] = 0; pGDTEDst->au32[1] = 0; } } return VINF_SUCCESS; } /** * Updates the Guest GDT & LDT virtualization based on current CPU state. * * @returns VBox status code. * @param pVM The VM to operate on. */ SELMR3DECL(int) SELMR3UpdateFromCPUM(PVM pVM) { int rc = VINF_SUCCESS; if (pVM->selm.s.fDisableMonitoring) { VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_GDT); VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_LDT); VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_TSS); return VINF_SUCCESS; } STAM_PROFILE_START(&pVM->selm.s.StatUpdateFromCPUM, a); /* * GDT sync */ if (VM_FF_ISSET(pVM, VM_FF_SELM_SYNC_GDT)) { /* * Always assume the best */ VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_GDT); /* If the GDT was changed, then make sure the LDT is checked too */ /** @todo only do this if the actual ldtr selector was changed; this is a bit excessive */ VM_FF_SET(pVM, VM_FF_SELM_SYNC_LDT); /* Same goes for the TSS selector */ VM_FF_SET(pVM, VM_FF_SELM_SYNC_TSS); /* * Get the GDTR and check if there is anything to do (there usually is). */ VBOXGDTR GDTR; CPUMGetGuestGDTR(pVM, &GDTR); if (GDTR.cbGdt < sizeof(VBOXDESC)) { Log(("No GDT entries...\n")); STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return VINF_SUCCESS; } /* * Read the Guest GDT. * ASSUMES that the entire GDT is in memory. */ RTUINT cbEffLimit = GDTR.cbGdt; PVBOXDESC pGDTE = &pVM->selm.s.paGdtHC[1]; rc = PGMPhysReadGCPtr(pVM, pGDTE, GDTR.pGdt + sizeof(VBOXDESC), cbEffLimit + 1 - sizeof(VBOXDESC)); if (VBOX_FAILURE(rc)) { /* * Read it page by page. * * Keep track of the last valid page and delay memsets and * adjust cbEffLimit to reflect the effective size. The latter * is something we do in the belief that the guest will probably * never actually commit the last page, thus allowing us to keep * our selectors in the high end of the GDT. */ RTUINT cbLeft = cbEffLimit + 1 - sizeof(VBOXDESC); RTGCPTR GCPtrSrc = (RTGCPTR)GDTR.pGdt + sizeof(VBOXDESC); uint8_t *pu8Dst = (uint8_t *)&pVM->selm.s.paGdtHC[1]; uint8_t *pu8DstInvalid = pu8Dst; while (cbLeft) { RTUINT cb = PAGE_SIZE - (GCPtrSrc & PAGE_OFFSET_MASK); cb = RT_MIN(cb, cbLeft); rc = PGMPhysReadGCPtr(pVM, pu8Dst, GCPtrSrc, cb); if (VBOX_SUCCESS(rc)) { if (pu8DstInvalid != pu8Dst) memset(pu8DstInvalid, 0, pu8Dst - pu8DstInvalid); GCPtrSrc += cb; pu8Dst += cb; pu8DstInvalid = pu8Dst; } else if ( rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT) { GCPtrSrc += cb; pu8Dst += cb; } else { AssertReleaseMsgFailed(("Couldn't read GDT at %RX32, rc=%Vrc!\n", GDTR.pGdt, rc)); STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return VERR_NOT_IMPLEMENTED; } cbLeft -= cb; } /* any invalid pages at the end? */ if (pu8DstInvalid != pu8Dst) { cbEffLimit = pu8DstInvalid - (uint8_t *)pVM->selm.s.paGdtHC - 1; /* If any GDTEs was invalidated, zero them. */ if (cbEffLimit < pVM->selm.s.cbEffGuestGdtLimit) memset(pu8DstInvalid + cbEffLimit + 1, 0, pVM->selm.s.cbEffGuestGdtLimit - cbEffLimit); } /* keep track of the effective limit. */ if (cbEffLimit != pVM->selm.s.cbEffGuestGdtLimit) { Log(("SELMR3UpdateFromCPUM: cbEffGuestGdtLimit=%#x -> %#x (actual %#x)\n", pVM->selm.s.cbEffGuestGdtLimit, cbEffLimit, GDTR.cbGdt)); pVM->selm.s.cbEffGuestGdtLimit = cbEffLimit; } } /* * Check if the Guest GDT intrudes on our GDT entries. */ // RTSEL aHyperGDT[MAX_NEEDED_HYPERVISOR_GDTS]; if (cbEffLimit >= pVM->selm.s.SelTSSTrap08) { #if 0 PVBOXDESC pGDTEStart = pVM->selm.s.paGdtHC; PVBOXDESC pGDTE = (PVBOXDESC)((char *)pGDTEStart + GDTR.cbGdt + 1 - sizeof(VBOXDESC)); int iGDT = 0; /* Disabling this for now; previously saw triple faults with OS/2, before fixing the above if statement */ Log(("Internal SELM GDT conflict: use non-present entries\n")); while (pGDTE > pGDTEStart && iGDT < MAX_NEEDED_HYPERVISOR_GDTS) { /* We can reuse non-present entries */ if (!pGDTE->Gen.u1Present) { aHyperGDT[iGDT] = ((uintptr_t)pGDTE - (uintptr_t)pVM->selm.s.paGdtHC) / sizeof(VBOXDESC); aHyperGDT[iGDT] = aHyperGDT[iGDT] << X86_SEL_SHIFT; Log(("SELM: Found unused GDT %04X\n", aHyperGDT[iGDT])); iGDT++; } pGDTE--; } if (iGDT != MAX_NEEDED_HYPERVISOR_GDTS) #endif { AssertReleaseMsgFailed(("Internal SELM GDT conflict.\n")); STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return VERR_NOT_IMPLEMENTED; } } /* * Work thru the copied GDT entries adjusting them for correct virtualization. */ PVBOXDESC pGDTEEnd = (PVBOXDESC)((char *)pGDTE + cbEffLimit + 1 - sizeof(VBOXDESC)); while (pGDTE < pGDTEEnd) { if (pGDTE->Gen.u1Present) { /* * Code and data selectors are generally 1:1, with the * 'little' adjustment we do for DPL 0 selectors. */ if (pGDTE->Gen.u1DescType) { /* * Hack for A-bit against Trap E on read-only GDT. */ /** @todo Fix this by loading ds and cs before turning off WP. */ pGDTE->Gen.u4Type |= X86_SEL_TYPE_ACCESSED; /* * All DPL 0 code and data segments are squeezed into DPL 1. * * We're skipping conforming segments here because those * cannot give us any trouble. */ if ( pGDTE->Gen.u2Dpl == 0 && (pGDTE->Gen.u4Type & (X86_SEL_TYPE_CODE | X86_SEL_TYPE_CONF)) != (X86_SEL_TYPE_CODE | X86_SEL_TYPE_CONF) ) pGDTE->Gen.u2Dpl = 1; } else { /* * System type selectors are marked not present. * Recompiler or special handling is required for these. */ /** @todo what about interrupt gates and rawr0? */ pGDTE->Gen.u1Present = 0; } } /* Next GDT entry. */ pGDTE++; } #if 0 /** @todo r=bird: The relocation code won't be working right. Start with the IF below. */ /* * Check if the Guest GDT intrudes on our GDT entries. */ if (cbEffLimit >= pVM->selm.s.SelTSSTrap08) { /* Reinitialize our hypervisor GDTs */ pVM->selm.s.SelCS = aHyperGDT[0]; pVM->selm.s.SelDS = aHyperGDT[1]; pVM->selm.s.SelCS64 = aHyperGDT[2]; pVM->selm.s.SelTSS = aHyperGDT[3]; pVM->selm.s.SelTSSTrap08 = aHyperGDT[4]; SELMR3Relocate(pVM); /** @todo r=bird: Must call VMR3Relocate! */ } #endif /* * Adjust the cached GDT limit. * Any GDT entries which have been removed must be cleared. */ if (pVM->selm.s.GuestGdtr.cbGdt != GDTR.cbGdt) { if (pVM->selm.s.GuestGdtr.cbGdt > GDTR.cbGdt) memset(pGDTE, 0, pVM->selm.s.GuestGdtr.cbGdt - GDTR.cbGdt); #ifndef SELM_TRACK_GUEST_GDT_CHANGES pVM->selm.s.GuestGdtr.cbGdt = GDTR.cbGdt; #endif } #ifdef SELM_TRACK_GUEST_GDT_CHANGES /* * Check if Guest's GDTR is changed. */ if ( GDTR.pGdt != pVM->selm.s.GuestGdtr.pGdt || GDTR.cbGdt != pVM->selm.s.GuestGdtr.cbGdt) { Log(("SELMR3UpdateFromCPUM: Guest's GDT is changed to pGdt=%08X cbGdt=%08X\n", GDTR.pGdt, GDTR.cbGdt)); /* * [Re]Register write virtual handler for guest's GDT. */ if (pVM->selm.s.GuestGdtr.pGdt != ~0U && pVM->selm.s.fGDTRangeRegistered) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GuestGdtr.pGdt); AssertRC(rc); } rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GDTR.pGdt, GDTR.pGdt + GDTR.cbGdt /* already inclusive */, 0, selmGuestGDTWriteHandler, "selmgcGuestGDTWriteHandler", 0, "Guest GDT write access handler"); if (VBOX_FAILURE(rc)) return rc; /* Update saved Guest GDTR. */ pVM->selm.s.GuestGdtr = GDTR; pVM->selm.s.fGDTRangeRegistered = true; } #endif } /* * TSS sync */ if (VM_FF_ISSET(pVM, VM_FF_SELM_SYNC_TSS)) { SELMR3SyncTSS(pVM); } /* * LDT sync */ if (VM_FF_ISSET(pVM, VM_FF_SELM_SYNC_LDT)) { /* * Always assume the best */ VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_LDT); /* * LDT handling is done similarly to the GDT handling with a shadow * array. However, since the LDT is expected to be swappable (at least * some ancient OSes makes it swappable) it must be floating and * synced on a per-page basis. * * Eventually we will change this to be fully on demand. Meaning that * we will only sync pages containing LDT selectors actually used and * let the #PF handler lazily sync pages as they are used. * (This applies to GDT too, when we start making OS/2 fast.) */ /* * First, determin the current LDT selector. */ RTSEL SelLdt = CPUMGetGuestLDTR(pVM); if ((SelLdt & X86_SEL_MASK) == 0) { /* ldtr = 0 - update hyper LDTR and deregister any active handler. */ CPUMSetHyperLDTR(pVM, 0); #ifdef SELM_TRACK_GUEST_LDT_CHANGES if (pVM->selm.s.GCPtrGuestLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestLdt); AssertRC(rc); pVM->selm.s.GCPtrGuestLdt = ~0U; } #endif STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return VINF_SUCCESS; } /* * Get the LDT selector. */ PVBOXDESC pDesc = &pVM->selm.s.paGdtHC[SelLdt >> X86_SEL_SHIFT]; RTGCPTR GCPtrLdt = pDesc->Gen.u16BaseLow | (pDesc->Gen.u8BaseHigh1 << 16) | (pDesc->Gen.u8BaseHigh2 << 24); unsigned cbLdt = pDesc->Gen.u16LimitLow | (pDesc->Gen.u4LimitHigh << 16); if (pDesc->Gen.u1Granularity) cbLdt = (cbLdt << PAGE_SHIFT) | PAGE_OFFSET_MASK; /* * Validate it. */ if ( !cbLdt || SelLdt >= pVM->selm.s.GuestGdtr.cbGdt || pDesc->Gen.u1DescType || pDesc->Gen.u4Type != X86_SEL_TYPE_SYS_LDT) { AssertMsg(!cbLdt, ("Invalid LDT %04x!\n", SelLdt)); /* cbLdt > 0: * This is quite impossible, so we do as most people do when faced with * the impossible, we simply ignore it. */ CPUMSetHyperLDTR(pVM, 0); #ifdef SELM_TRACK_GUEST_LDT_CHANGES if (pVM->selm.s.GCPtrGuestLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestLdt); AssertRC(rc); pVM->selm.s.GCPtrGuestLdt = ~0U; } #endif STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return VINF_SUCCESS; } /** @todo check what intel does about odd limits. */ AssertMsg(RT_ALIGN(cbLdt + 1, sizeof(VBOXDESC)) == cbLdt + 1 && cbLdt <= 0xffff, ("cbLdt=%d\n", cbLdt)); /* * Use the cached guest ldt address if the descriptor has already been modified (see below) * (this is necessary due to redundant LDT updates; see todo above at GDT sync) */ if (MMHyperIsInsideArea(pVM, GCPtrLdt) == true) GCPtrLdt = pVM->selm.s.GCPtrGuestLdt; /* use the old one */ #ifdef SELM_TRACK_GUEST_LDT_CHANGES /** @todo Handle only present LDT segments. */ // if (pDesc->Gen.u1Present) { /* * Check if Guest's LDT address/limit is changed. */ if ( GCPtrLdt != pVM->selm.s.GCPtrGuestLdt || cbLdt != pVM->selm.s.cbLdtLimit) { Log(("SELMR3UpdateFromCPUM: Guest LDT changed to from %VGv:%04x to %VGv:%04x. (GDTR=%VGv:%04x)\n", pVM->selm.s.GCPtrGuestLdt, pVM->selm.s.cbLdtLimit, GCPtrLdt, cbLdt, pVM->selm.s.GuestGdtr.pGdt, pVM->selm.s.GuestGdtr.cbGdt)); /* * [Re]Register write virtual handler for guest's GDT. * In the event of LDT overlapping something, don't install it just assume it's being updated. */ if (pVM->selm.s.GCPtrGuestLdt != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestLdt); AssertRC(rc); } #ifdef DEBUG if (pDesc->Gen.u1Present) Log(("LDT selector marked not present!!\n")); #endif rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GCPtrLdt, GCPtrLdt + cbLdt /* already inclusive */, 0, selmGuestLDTWriteHandler, "selmgcGuestLDTWriteHandler", 0, "Guest LDT write access handler"); if (rc == VERR_PGM_HANDLER_VIRTUAL_CONFLICT) { /** @todo investigate the various cases where conflicts happen and try avoid them by enh. the instruction emulation. */ pVM->selm.s.GCPtrGuestLdt = ~0; Log(("WARNING: Guest LDT (%VGv:%04x) conflicted with existing access range!! Assumes LDT is begin updated. (GDTR=%VGv:%04x)\n", GCPtrLdt, cbLdt, pVM->selm.s.GuestGdtr.pGdt, pVM->selm.s.GuestGdtr.cbGdt)); } else if (VBOX_SUCCESS(rc)) pVM->selm.s.GCPtrGuestLdt = GCPtrLdt; else { CPUMSetHyperLDTR(pVM, 0); STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return rc; } pVM->selm.s.cbLdtLimit = cbLdt; } } #else pVM->selm.s.cbLdtLimit = cbLdt; #endif /* * Calc Shadow LDT base. */ unsigned off; pVM->selm.s.offLdtHyper = off = (GCPtrLdt & PAGE_OFFSET_MASK); RTGCPTR GCPtrShadowLDT = (RTGCPTR)((RTGCUINTPTR)pVM->selm.s.GCPtrLdt + off); PVBOXDESC pShadowLDT = (PVBOXDESC)((uintptr_t)pVM->selm.s.HCPtrLdt + off); /* * Enable the LDT selector in the shadow GDT. */ pDesc->Gen.u1Present = 1; pDesc->Gen.u16BaseLow = RT_LOWORD(GCPtrShadowLDT); pDesc->Gen.u8BaseHigh1 = RT_BYTE3(GCPtrShadowLDT); pDesc->Gen.u8BaseHigh2 = RT_BYTE4(GCPtrShadowLDT); pDesc->Gen.u1Available = 0; pDesc->Gen.u1Reserved = 0; if (cbLdt > 0xffff) { cbLdt = 0xffff; pDesc->Gen.u4LimitHigh = 0; pDesc->Gen.u16LimitLow = pDesc->Gen.u1Granularity ? 0xf : 0xffff; } /* * Set Hyper LDTR and notify TRPM. */ CPUMSetHyperLDTR(pVM, SelLdt); /* * Loop synchronising the LDT page by page. */ /** @todo investigate how intel handle various operations on half present cross page entries. */ off = GCPtrLdt & (sizeof(VBOXDESC) - 1); AssertMsg(!off, ("LDT is not aligned on entry size! GCPtrLdt=%08x\n", GCPtrLdt)); GCPtrLdt += sizeof(VBOXDESC); pShadowLDT++; unsigned cbLeft = cbLdt + 1 - sizeof(VBOXDESC); PVBOXDESC pLDTE = pShadowLDT; while (cbLeft) { /* * Read a chunk. */ unsigned cbChunk = PAGE_SIZE - ((RTGCUINTPTR)GCPtrLdt & PAGE_OFFSET_MASK); if (cbChunk > cbLeft) cbChunk = cbLeft; rc = PGMPhysReadGCPtr(pVM, pShadowLDT, GCPtrLdt, cbChunk); if (VBOX_SUCCESS(rc)) { /* * Mark page */ rc = PGMMapSetPage(pVM, GCPtrShadowLDT & PAGE_BASE_GC_MASK, PAGE_SIZE, X86_PTE_P | X86_PTE_A | X86_PTE_D); AssertRC(rc); /* * Loop thru the available LDT entries. * Figure out where to start and end and the potential cross pageness of * things adds a little complexity. pLDTE is updated there and not in the * 'next' part of the loop. The pLDTEEnd is inclusive. */ PVBOXDESC pLDTEEnd = (PVBOXDESC)((uintptr_t)pShadowLDT + cbChunk) - 1; if (pLDTE + 1 < pShadowLDT) pLDTE = (PVBOXDESC)((uintptr_t)pShadowLDT + off); while (pLDTE <= pLDTEEnd) { if (pLDTE->Gen.u1Present) { /* * Code and data selectors are generally 1:1, with the * 'little' adjustment we do for DPL 0 selectors. */ if (pLDTE->Gen.u1DescType) { /* * Hack for A-bit against Trap E on read-only GDT. */ /** @todo Fix this by loading ds and cs before turning off WP. */ if (!(pLDTE->Gen.u4Type & X86_SEL_TYPE_ACCESSED)) pLDTE->Gen.u4Type |= X86_SEL_TYPE_ACCESSED; /* * All DPL 0 code and data segments are squeezed into DPL 1. * * We're skipping conforming segments here because those * cannot give us any trouble. */ if ( pLDTE->Gen.u2Dpl == 0 && (pLDTE->Gen.u4Type & (X86_SEL_TYPE_CODE | X86_SEL_TYPE_CONF)) != (X86_SEL_TYPE_CODE | X86_SEL_TYPE_CONF) ) pLDTE->Gen.u2Dpl = 1; } else { /* * System type selectors are marked not present. * Recompiler or special handling is required for these. */ /** @todo what about interrupt gates and rawr0? */ pLDTE->Gen.u1Present = 0; } } /* Next LDT entry. */ pLDTE++; } } else { AssertMsg(rc == VERR_PAGE_NOT_PRESENT || rc == VERR_PAGE_TABLE_NOT_PRESENT, ("rc=%d\n", rc)); rc = PGMMapSetPage(pVM, GCPtrShadowLDT & PAGE_BASE_GC_MASK, PAGE_SIZE, 0); AssertRC(rc); } /* * Advance to the next page. */ cbLeft -= cbChunk; GCPtrShadowLDT += cbChunk; pShadowLDT = (PVBOXDESC)((char *)pShadowLDT + cbChunk); GCPtrLdt += cbChunk; } } STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return VINF_SUCCESS; } /** * \#PF Handler callback for virtual access handler ranges. * * Important to realize that a physical page in a range can have aliases, and * for ALL and WRITE handlers these will also trigger. * * @returns VINF_SUCCESS if the handler have carried out the operation. * @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation. * @param pVM VM Handle. * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!) * @param pvPtr The HC mapping of that address. * @param pvBuf What the guest is reading/writing. * @param cbBuf How much it's reading/writing. * @param enmAccessType The access type. * @param pvUser User argument. */ static DECLCALLBACK(int) selmGuestGDTWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser) { Assert(enmAccessType == PGMACCESSTYPE_WRITE); Log(("selmGuestGDTWriteHandler: write to %VGv size %d\n", GCPtr, cbBuf)); VM_FF_SET(pVM, VM_FF_SELM_SYNC_GDT); return VINF_PGM_HANDLER_DO_DEFAULT; } /** * \#PF Handler callback for virtual access handler ranges. * * Important to realize that a physical page in a range can have aliases, and * for ALL and WRITE handlers these will also trigger. * * @returns VINF_SUCCESS if the handler have carried out the operation. * @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation. * @param pVM VM Handle. * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!) * @param pvPtr The HC mapping of that address. * @param pvBuf What the guest is reading/writing. * @param cbBuf How much it's reading/writing. * @param enmAccessType The access type. * @param pvUser User argument. */ static DECLCALLBACK(int) selmGuestLDTWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser) { Assert(enmAccessType == PGMACCESSTYPE_WRITE); Log(("selmGuestLDTWriteHandler: write to %VGv size %d\n", GCPtr, cbBuf)); VM_FF_SET(pVM, VM_FF_SELM_SYNC_LDT); return VINF_PGM_HANDLER_DO_DEFAULT; } /** * \#PF Handler callback for virtual access handler ranges. * * Important to realize that a physical page in a range can have aliases, and * for ALL and WRITE handlers these will also trigger. * * @returns VINF_SUCCESS if the handler have carried out the operation. * @returns VINF_PGM_HANDLER_DO_DEFAULT if the caller should carry out the access operation. * @param pVM VM Handle. * @param GCPtr The virtual address the guest is writing to. (not correct if it's an alias!) * @param pvPtr The HC mapping of that address. * @param pvBuf What the guest is reading/writing. * @param cbBuf How much it's reading/writing. * @param enmAccessType The access type. * @param pvUser User argument. */ static DECLCALLBACK(int) selmGuestTSSWriteHandler(PVM pVM, RTGCPTR GCPtr, void *pvPtr, void *pvBuf, size_t cbBuf, PGMACCESSTYPE enmAccessType, void *pvUser) { Assert(enmAccessType == PGMACCESSTYPE_WRITE); Log(("selmGuestTSSWriteHandler: write to %VGv size %d\n", GCPtr, cbBuf)); VM_FF_SET(pVM, VM_FF_SELM_SYNC_TSS); return VINF_PGM_HANDLER_DO_DEFAULT; } /** * Check if the TSS ring 0 stack selector and pointer were updated (for now) * * @returns VBox status code. * @param pVM The VM to operate on. */ SELMR3DECL(int) SELMR3SyncTSS(PVM pVM) { int rc; if (pVM->selm.s.fDisableMonitoring) { VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_TSS); return VINF_SUCCESS; } /** @todo r=bird: SELMR3SyncTSS should be VMMAll code. * All the base, size, flags and stuff must be kept up to date in the CPUM tr register. */ STAM_PROFILE_START(&pVM->selm.s.StatTSSSync, a); Assert(!VM_FF_ISSET(pVM, VM_FF_SELM_SYNC_GDT)); Assert(VM_FF_ISSET(pVM, VM_FF_SELM_SYNC_TSS)); /* * TSS sync */ RTSEL SelTss = CPUMGetGuestTR(pVM); if (SelTss & X86_SEL_MASK) { /** @todo r=bird: strictly speaking, this is wrong as we shouldn't bother with changes to * the TSS selector once its loaded. There are a bunch of this kind of problems (see Sander's * comment in the unzip defect) * The first part here should only be done when we're loading TR. The latter part which is * updating of the ss0:esp0 pair can be done by the access handler now since we can trap all * accesses, also REM ones. */ /* * Guest TR is not NULL. */ PVBOXDESC pDesc = &pVM->selm.s.paGdtHC[SelTss >> X86_SEL_SHIFT]; RTGCPTR GCPtrTss = pDesc->Gen.u16BaseLow | (pDesc->Gen.u8BaseHigh1 << 16) | (pDesc->Gen.u8BaseHigh2 << 24); unsigned cbTss = pDesc->Gen.u16LimitLow | (pDesc->Gen.u4LimitHigh << 16); if (pDesc->Gen.u1Granularity) cbTss = (cbTss << PAGE_SHIFT) | PAGE_OFFSET_MASK; cbTss++; pVM->selm.s.cbGuestTss = cbTss; pVM->selm.s.fGuestTss32Bit = pDesc->Gen.u4Type == X86_SEL_TYPE_SYS_386_TSS_AVAIL || pDesc->Gen.u4Type == X86_SEL_TYPE_SYS_386_TSS_BUSY; /* Don't bother with anything but the core structure. (Actually all we care for is the r0 ss.) */ if (cbTss > sizeof(VBOXTSS)) cbTss = sizeof(VBOXTSS); AssertMsg((GCPtrTss >> PAGE_SHIFT) == ((GCPtrTss + cbTss - 1) >> PAGE_SHIFT), ("GCPtrTss=%VGv cbTss=%#x - We assume everything is inside one page!\n", GCPtrTss, cbTss)); // All system GDTs are marked not present above. That explains why this check fails. //if (pDesc->Gen.u1Present) /** @todo Handle only present TSS segments. */ { /* * Check if Guest's TSS is changed. */ if ( GCPtrTss != pVM->selm.s.GCPtrGuestTss || cbTss != pVM->selm.s.cbMonitoredGuestTss) { Log(("SELMR3UpdateFromCPUM: Guest's TSS is changed to pTss=%08X cbTss=%08X cbGuestTss\n", GCPtrTss, cbTss, pVM->selm.s.cbGuestTss)); /* * Validate it. */ if ( SelTss & X86_SEL_LDT || !cbTss || SelTss >= pVM->selm.s.GuestGdtr.cbGdt || pDesc->Gen.u1DescType || ( pDesc->Gen.u4Type != X86_SEL_TYPE_SYS_286_TSS_AVAIL && pDesc->Gen.u4Type != X86_SEL_TYPE_SYS_286_TSS_BUSY && pDesc->Gen.u4Type != X86_SEL_TYPE_SYS_386_TSS_AVAIL && pDesc->Gen.u4Type != X86_SEL_TYPE_SYS_386_TSS_BUSY) ) { AssertMsgFailed(("Invalid Guest TSS %04x!\n", SelTss)); } else { /* * [Re]Register write virtual handler for guest's TSS. */ if (pVM->selm.s.GCPtrGuestTss != ~0U) { rc = PGMHandlerVirtualDeregister(pVM, pVM->selm.s.GCPtrGuestTss); AssertRC(rc); } rc = PGMR3HandlerVirtualRegister(pVM, PGMVIRTHANDLERTYPE_WRITE, GCPtrTss, GCPtrTss + cbTss - 1, 0, selmGuestTSSWriteHandler, "selmgcGuestTSSWriteHandler", 0, "Guest TSS write access handler"); if (VBOX_FAILURE(rc)) { STAM_PROFILE_STOP(&pVM->selm.s.StatUpdateFromCPUM, a); return rc; } /* Update saved Guest TSS info. */ pVM->selm.s.GCPtrGuestTss = GCPtrTss; pVM->selm.s.cbMonitoredGuestTss = cbTss; pVM->selm.s.GCSelTss = SelTss; } } /* Update the ring 0 stack selector and base address */ /* feeling very lazy; reading too much */ VBOXTSS tss; rc = PGMPhysReadGCPtr(pVM, &tss, GCPtrTss, sizeof(VBOXTSS)); if (VBOX_SUCCESS(rc)) { #ifdef DEBUG uint32_t ssr0, espr0; SELMGetRing1Stack(pVM, &ssr0, &espr0); ssr0 &= ~1; if (ssr0 != tss.ss0 || espr0 != tss.esp0) Log(("SELMR3SyncTSS: Updating TSS ring 0 stack to %04X:%08X\n", tss.ss0, tss.esp0)); Log(("offIoBitmap=%#x\n", tss.offIoBitmap)); #endif /* Update our TSS structure for the guest's ring 1 stack */ SELMSetRing1Stack(pVM, tss.ss0 | 1, tss.esp0); } else { /** @note the ring 0 stack selector and base address are updated on demand in this case. */ /** @todo handle these dependencies better! */ TRPMR3SetGuestTrapHandler(pVM, 0x2E, TRPM_INVALID_HANDLER); TRPMR3SetGuestTrapHandler(pVM, 0x80, TRPM_INVALID_HANDLER); pVM->selm.s.fSyncTSSRing0Stack = true; } VM_FF_CLEAR(pVM, VM_FF_SELM_SYNC_TSS); } } STAM_PROFILE_STOP(&pVM->selm.s.StatTSSSync, a); return VINF_SUCCESS; } /** * Compares the Guest GDT and LDT with the shadow tables. * This is a VBOX_STRICT only function. * * @returns VBox status code. * @param pVM The VM Handle. */ SELMR3DECL(int) SELMR3DebugCheck(PVM pVM) { #ifdef VBOX_STRICT /* * Get GDTR and check for conflict. */ VBOXGDTR GDTR; CPUMGetGuestGDTR(pVM, &GDTR); if (GDTR.cbGdt == 0) return VINF_SUCCESS; #if 0 if (GDTR.cbGdt >= (unsigned)(pVM->selm.s.SelTSSTrap08 >> X86_SEL_SHIFT)) { AssertReleaseMsgFailed(("Internal SELM GDT conflict.\n")); return VERR_NOT_IMPLEMENTED; } #endif if (GDTR.cbGdt != pVM->selm.s.GuestGdtr.cbGdt) Log(("SELMR3DebugCheck: limits have changed! new=%d old=%d\n", GDTR.cbGdt, pVM->selm.s.GuestGdtr.cbGdt)); /* * Loop thru the GDT checking each entry. */ RTGCPTR GCPtrGDTEGuest = GDTR.pGdt; PVBOXDESC pGDTE = pVM->selm.s.paGdtHC; PVBOXDESC pGDTEEnd = (PVBOXDESC)((uintptr_t)pGDTE + GDTR.cbGdt); while (pGDTE < pGDTEEnd) { VBOXDESC GDTEGuest; int rc = PGMPhysReadGCPtr(pVM, &GDTEGuest, GCPtrGDTEGuest, sizeof(GDTEGuest)); if (VBOX_SUCCESS(rc)) { if (pGDTE->Gen.u1DescType || pGDTE->Gen.u4Type != X86_SEL_TYPE_SYS_LDT) { if ( pGDTE->Gen.u16LimitLow != GDTEGuest.Gen.u16LimitLow || pGDTE->Gen.u4LimitHigh != GDTEGuest.Gen.u4LimitHigh || pGDTE->Gen.u16BaseLow != GDTEGuest.Gen.u16BaseLow || pGDTE->Gen.u8BaseHigh1 != GDTEGuest.Gen.u8BaseHigh1 || pGDTE->Gen.u8BaseHigh2 != GDTEGuest.Gen.u8BaseHigh2 || pGDTE->Gen.u1DefBig != GDTEGuest.Gen.u1DefBig || pGDTE->Gen.u1DescType != GDTEGuest.Gen.u1DescType) { unsigned iGDT = pGDTE - pVM->selm.s.paGdtHC; SELMR3DumpDescriptor(*pGDTE, iGDT << 3, "SELMR3DebugCheck: GDT mismatch, shadow"); SELMR3DumpDescriptor(GDTEGuest, iGDT << 3, "SELMR3DebugCheck: GDT mismatch, guest"); } } } /* Advance to the next descriptor. */ GCPtrGDTEGuest += sizeof(VBOXDESC); pGDTE++; } /* * LDT? */ RTSEL SelLdt = CPUMGetGuestLDTR(pVM); if ((SelLdt & X86_SEL_MASK) == 0) return VINF_SUCCESS; if (SelLdt > GDTR.cbGdt) { Log(("SELMR3DebugCheck: ldt is out of bound SelLdt=%#x\n", SelLdt)); return VERR_INTERNAL_ERROR; } VBOXDESC LDTDesc; int rc = PGMPhysReadGCPtr(pVM, &LDTDesc, GDTR.pGdt + (SelLdt & X86_SEL_MASK), sizeof(LDTDesc)); if (VBOX_FAILURE(rc)) { Log(("SELMR3DebugCheck: Failed to read LDT descriptor. rc=%d\n", rc)); return rc; } RTGCPTR GCPtrLDTEGuest = LDTDesc.Gen.u16BaseLow | (LDTDesc.Gen.u8BaseHigh1 << 16) | (LDTDesc.Gen.u8BaseHigh2 << 24); unsigned cbLdt = LDTDesc.Gen.u16LimitLow | (LDTDesc.Gen.u4LimitHigh << 16); if (LDTDesc.Gen.u1Granularity) cbLdt = (cbLdt << PAGE_SHIFT) | PAGE_OFFSET_MASK; /* * Validate it. */ if (!cbLdt) return VINF_SUCCESS; /** @todo check what intel does about odd limits. */ AssertMsg(RT_ALIGN(cbLdt + 1, sizeof(VBOXDESC)) == cbLdt + 1 && cbLdt <= 0xffff, ("cbLdt=%d\n", cbLdt)); if ( LDTDesc.Gen.u1DescType || LDTDesc.Gen.u4Type != X86_SEL_TYPE_SYS_LDT || SelLdt >= pVM->selm.s.GuestGdtr.cbGdt) { Log(("SELmR3DebugCheck: Invalid LDT %04x!\n", SelLdt)); return VERR_INTERNAL_ERROR; } /* * Loop thru the LDT checking each entry. */ unsigned off = (GCPtrLDTEGuest & PAGE_OFFSET_MASK); PVBOXDESC pLDTE = (PVBOXDESC)((uintptr_t)pVM->selm.s.HCPtrLdt + off); PVBOXDESC pLDTEEnd = (PVBOXDESC)((uintptr_t)pGDTE + cbLdt); while (pLDTE < pLDTEEnd) { VBOXDESC LDTEGuest; int rc = PGMPhysReadGCPtr(pVM, &LDTEGuest, GCPtrLDTEGuest, sizeof(LDTEGuest)); if (VBOX_SUCCESS(rc)) { if ( pLDTE->Gen.u16LimitLow != LDTEGuest.Gen.u16LimitLow || pLDTE->Gen.u4LimitHigh != LDTEGuest.Gen.u4LimitHigh || pLDTE->Gen.u16BaseLow != LDTEGuest.Gen.u16BaseLow || pLDTE->Gen.u8BaseHigh1 != LDTEGuest.Gen.u8BaseHigh1 || pLDTE->Gen.u8BaseHigh2 != LDTEGuest.Gen.u8BaseHigh2 || pLDTE->Gen.u1DefBig != LDTEGuest.Gen.u1DefBig || pLDTE->Gen.u1DescType != LDTEGuest.Gen.u1DescType) { unsigned iLDT = pLDTE - (PVBOXDESC)((uintptr_t)pVM->selm.s.HCPtrLdt + off); SELMR3DumpDescriptor(*pLDTE, iLDT << 3, "SELMR3DebugCheck: LDT mismatch, shadow"); SELMR3DumpDescriptor(LDTEGuest, iLDT << 3, "SELMR3DebugCheck: LDT mismatch, guest"); } } /* Advance to the next descriptor. */ GCPtrLDTEGuest += sizeof(VBOXDESC); pLDTE++; } #else NOREF(pVM); #endif return VINF_SUCCESS; } /** * Validates the RawR0 TSS values against the one in the Guest TSS. * * @returns true if it matches. * @returns false and assertions on mismatch.. * @param pVM VM Handle. */ SELMR3DECL(bool) SELMR3CheckTSS(PVM pVM) { #ifdef VBOX_STRICT RTSEL SelTss = CPUMGetGuestTR(pVM); if (SelTss & X86_SEL_MASK) { AssertMsg((SelTss & X86_SEL_MASK) == (pVM->selm.s.GCSelTss & X86_SEL_MASK), ("New TSS selector = %04X, old TSS selector = %04X\n", SelTss, pVM->selm.s.GCSelTss)); /* * Guest TR is not NULL. */ PVBOXDESC pDesc = &pVM->selm.s.paGdtHC[SelTss >> X86_SEL_SHIFT]; RTGCPTR GCPtrTss = pDesc->Gen.u16BaseLow | (pDesc->Gen.u8BaseHigh1 << 16) | (pDesc->Gen.u8BaseHigh2 << 24); unsigned cbTss = pDesc->Gen.u16LimitLow | (pDesc->Gen.u4LimitHigh << 16); if (pDesc->Gen.u1Granularity) cbTss = (cbTss << PAGE_SHIFT) | PAGE_OFFSET_MASK; cbTss++; /* Don't bother with anything but the core structure. (Actually all we care for is the r0 ss.) */ if (cbTss > sizeof(VBOXTSS)) cbTss = sizeof(VBOXTSS); AssertMsg((GCPtrTss >> PAGE_SHIFT) == ((GCPtrTss + cbTss - 1) >> PAGE_SHIFT), ("GCPtrTss=%VGv cbTss=%#x - We assume everything is inside one page!\n", GCPtrTss, cbTss)); // All system GDTs are marked not present above. That explains why this check fails. //if (pDesc->Gen.u1Present) /** @todo Handle only present TSS segments. */ { /* * Check if Guest's TSS was changed. */ if ( GCPtrTss != pVM->selm.s.GCPtrGuestTss || cbTss != pVM->selm.s.cbMonitoredGuestTss) { AssertMsgFailed(("Guest's TSS (Sel 0x%X) is changed from %RGv:%04x to %RGv:%04x\n", SelTss, pVM->selm.s.GCPtrGuestTss, pVM->selm.s.cbMonitoredGuestTss, GCPtrTss, cbTss)); } } } if (!pVM->selm.s.fSyncTSSRing0Stack) { RTGCPTR pGuestTSS = pVM->selm.s.GCPtrGuestTss; uint32_t ESPR0; int rc = PGMPhysReadGCPtr(pVM, &ESPR0, pGuestTSS + RT_OFFSETOF(VBOXTSS, esp0), sizeof(ESPR0)); if (VBOX_SUCCESS(rc)) { RTSEL SelSS0; rc = PGMPhysReadGCPtr(pVM, &SelSS0, pGuestTSS + RT_OFFSETOF(VBOXTSS, ss0), sizeof(SelSS0)); if (VBOX_SUCCESS(rc)) { if ( ESPR0 == pVM->selm.s.Tss.esp1 && SelSS0 == (pVM->selm.s.Tss.ss1 & ~1)) return true; RTGCPHYS GCPhys; uint64_t fFlags; rc = PGMGstGetPage(pVM, pGuestTSS, &fFlags, &GCPhys); AssertRC(rc); AssertMsgFailed(("TSS out of sync!! (%04X:%08X vs %04X:%08X (guest)) Tss=%VGv Phys=%VGp\n", (pVM->selm.s.Tss.ss1 & ~1), pVM->selm.s.Tss.esp1, SelSS0, ESPR0, pGuestTSS, GCPhys)); } else AssertRC(rc); } else /* Happens during early Windows XP boot when it is switching page tables. */ Assert(rc == VINF_SUCCESS || ((rc == VERR_PAGE_TABLE_NOT_PRESENT || rc == VERR_PAGE_NOT_PRESENT) && !(CPUMGetGuestEFlags(pVM) & X86_EFL_IF))); } return false; #else NOREF(pVM); return true; #endif } /** * Returns flat address and limit of LDT by LDT selector from guest GDTR. * * Fully validate selector. * * @returns VBox status. * @param pVM VM Handle. * @param SelLdt LDT selector. * @param ppvLdt Where to store the flat address of LDT. * @param pcbLimit Where to store LDT limit. */ SELMDECL(int) SELMGetLDTFromSel(PVM pVM, RTSEL SelLdt, PRTGCPTR ppvLdt, unsigned *pcbLimit) { /* Get guest GDTR. */ VBOXGDTR GDTR; CPUMGetGuestGDTR(pVM, &GDTR); /* Check selector TI and GDT limit. */ if ( SelLdt & X86_SEL_LDT || (SelLdt > GDTR.cbGdt)) return VERR_INVALID_SELECTOR; /* Read descriptor from GC. */ VBOXDESC Desc; int rc = PGMPhysReadGCPtr(pVM, (void *)&Desc, (RTGCPTR)(GDTR.pGdt + (SelLdt & X86_SEL_MASK)), sizeof(Desc)); if (VBOX_FAILURE(rc)) { /* fatal */ AssertMsgFailed(("Can't read LDT descriptor for selector=%04X\n", SelLdt)); return VERR_SELECTOR_NOT_PRESENT; } /* Check if LDT descriptor is not present. */ if (Desc.Gen.u1Present == 0) return VERR_SELECTOR_NOT_PRESENT; /* Check LDT descriptor type. */ if ( Desc.Gen.u1DescType == 1 || Desc.Gen.u4Type != X86_SEL_TYPE_SYS_LDT) return VERR_INVALID_SELECTOR; /* LDT descriptor is ok. */ if (ppvLdt) { *ppvLdt = (RTGCPTR)( (Desc.Gen.u8BaseHigh2 << 24) | (Desc.Gen.u8BaseHigh1 << 16) | Desc.Gen.u16BaseLow); *pcbLimit = Desc.Gen.u4LimitHigh << 16 | Desc.Gen.u16LimitLow; } return VINF_SUCCESS; } /** * Gets information about a selector. * Intended for the debugger mostly and will prefer the guest * descriptor tables over the shadow ones. * * @returns VINF_SUCCESS on success. * @returns VERR_INVALID_SELECTOR if the selector isn't fully inside the descriptor table. * @returns VERR_SELECTOR_NOT_PRESENT if the selector wasn't present. * @returns VERR_PAGE_TABLE_NOT_PRESENT or VERR_PAGE_NOT_PRESENT if the pagetable or page * backing the selector table wasn't present. * @returns Other VBox status code on other errors. * * @param pVM VM handle. * @param Sel The selector to get info about. * @param pSelInfo Where to store the information. */ SELMR3DECL(int) SELMR3GetSelectorInfo(PVM pVM, RTSEL Sel, PSELMSELINFO pSelInfo) { Assert(pSelInfo); /* * Read the descriptor entry */ VBOXDESC Desc; if ( !(Sel & X86_SEL_LDT) && ( pVM->selm.s.SelCS == (Sel & X86_SEL_MASK) || pVM->selm.s.SelDS == (Sel & X86_SEL_MASK) || pVM->selm.s.SelCS64 == (Sel & X86_SEL_MASK) || pVM->selm.s.SelTSS == (Sel & X86_SEL_MASK) || pVM->selm.s.SelTSSTrap08 == (Sel & X86_SEL_MASK)) ) { /* * Hypervisor descriptor. */ pSelInfo->fHyper = true; Desc = pVM->selm.s.paGdtHC[Sel >> X86_SEL_SHIFT]; } else if (CPUMIsGuestInProtectedMode(pVM)) { /* * Read it from the guest descriptor table. */ pSelInfo->fHyper = false; VBOXGDTR Gdtr; RTGCPTR GCPtrDesc; CPUMGetGuestGDTR(pVM, &Gdtr); if (!(Sel & X86_SEL_LDT)) { /* GDT */ if ((unsigned)(Sel & X86_SEL_MASK) + sizeof(VBOXDESC) - 1 > (unsigned)Gdtr.cbGdt) return VERR_INVALID_SELECTOR; GCPtrDesc = Gdtr.pGdt + (Sel & X86_SEL_MASK); } else { /* * LDT - must locate the LDT first... */ RTSEL SelLdt = CPUMGetGuestLDTR(pVM); if ( (unsigned)(SelLdt & X86_SEL_MASK) < sizeof(VBOXDESC) /* the first selector is invalid, right? */ || (unsigned)(SelLdt & X86_SEL_MASK) + sizeof(VBOXDESC) - 1 > (unsigned)Gdtr.cbGdt) return VERR_INVALID_SELECTOR; GCPtrDesc = Gdtr.pGdt + (SelLdt & X86_SEL_MASK); int rc = PGMPhysReadGCPtr(pVM, &Desc, GCPtrDesc, sizeof(Desc)); if (VBOX_FAILURE(rc)) return rc; /* validate the LDT descriptor. */ if (Desc.Gen.u1Present == 0) return VERR_SELECTOR_NOT_PRESENT; if ( Desc.Gen.u1DescType == 1 || Desc.Gen.u4Type != X86_SEL_TYPE_SYS_LDT) return VERR_INVALID_SELECTOR; unsigned cbLimit = Desc.Gen.u4LimitHigh << 16 | Desc.Gen.u16LimitLow; if (Desc.Gen.u1Granularity) cbLimit = (cbLimit << PAGE_SHIFT) | PAGE_OFFSET_MASK; if ((unsigned)(Sel & X86_SEL_MASK) + sizeof(VBOXDESC) - 1 > cbLimit) return VERR_INVALID_SELECTOR; /* calc the descriptor location. */ GCPtrDesc = (Desc.Gen.u8BaseHigh2 << 24) | (Desc.Gen.u8BaseHigh1 << 16) | Desc.Gen.u16BaseLow; GCPtrDesc += (Sel & X86_SEL_MASK); } /* read the descriptor. */ int rc = PGMPhysReadGCPtr(pVM, &Desc, GCPtrDesc, sizeof(Desc)); if (VBOX_FAILURE(rc)) return rc; } else { /* * We're in real mode. */ pSelInfo->Sel = Sel; pSelInfo->GCPtrBase = Sel << 4; pSelInfo->cbLimit = 0xffff; pSelInfo->fHyper = false; pSelInfo->fRealMode = true; memset(&pSelInfo->Raw, 0, sizeof(pSelInfo->Raw)); return VINF_SUCCESS; } /* * Extract the base and limit */ pSelInfo->Sel = Sel; pSelInfo->Raw = Desc; pSelInfo->cbLimit = Desc.Gen.u4LimitHigh << 16 | Desc.Gen.u16LimitLow; if (Desc.Gen.u1Granularity) pSelInfo->cbLimit = (pSelInfo->cbLimit << PAGE_SHIFT) | PAGE_OFFSET_MASK; pSelInfo->GCPtrBase = (Desc.Gen.u8BaseHigh2 << 24) | (Desc.Gen.u8BaseHigh1 << 16) | Desc.Gen.u16BaseLow; pSelInfo->fRealMode = false; return VINF_SUCCESS; } /** * Gets information about a selector from the shadow tables. * * This is intended to be faster than the SELMR3GetSelectorInfo() method, but requires * that the caller ensures that the shadow tables are up to date. * * @returns VINF_SUCCESS on success. * @returns VERR_INVALID_SELECTOR if the selector isn't fully inside the descriptor table. * @returns VERR_SELECTOR_NOT_PRESENT if the selector wasn't present. * @returns VERR_PAGE_TABLE_NOT_PRESENT or VERR_PAGE_NOT_PRESENT if the pagetable or page * backing the selector table wasn't present. * @returns Other VBox status code on other errors. * * @param pVM VM handle. * @param Sel The selector to get info about. * @param pSelInfo Where to store the information. */ SELMR3DECL(int) SELMR3GetShadowSelectorInfo(PVM pVM, RTSEL Sel, PSELMSELINFO pSelInfo) { Assert(pSelInfo); /* * Read the descriptor entry */ VBOXDESC Desc; if (!(Sel & X86_SEL_LDT)) { /* * Global descriptor. */ Desc = pVM->selm.s.paGdtHC[Sel >> X86_SEL_SHIFT]; pSelInfo->fHyper = pVM->selm.s.SelCS == (Sel & X86_SEL_MASK) || pVM->selm.s.SelDS == (Sel & X86_SEL_MASK) || pVM->selm.s.SelCS64 == (Sel & X86_SEL_MASK) || pVM->selm.s.SelTSS == (Sel & X86_SEL_MASK) || pVM->selm.s.SelTSSTrap08 == (Sel & X86_SEL_MASK); /** @todo check that the GDT offset is valid. */ } else { /* * Local Descriptor. */ PVBOXDESC paLDT = (PVBOXDESC)((char *)pVM->selm.s.HCPtrLdt + pVM->selm.s.offLdtHyper); Desc = paLDT[Sel >> X86_SEL_SHIFT]; /** @todo check if the LDT page is actually available. */ /** @todo check that the LDT offset is valid. */ pSelInfo->fHyper = false; } /* * Extract the base and limit */ pSelInfo->Sel = Sel; pSelInfo->Raw = Desc; pSelInfo->cbLimit = Desc.Gen.u4LimitHigh << 16 | Desc.Gen.u16LimitLow; if (Desc.Gen.u1Granularity) pSelInfo->cbLimit = (pSelInfo->cbLimit << PAGE_SHIFT) | PAGE_OFFSET_MASK; pSelInfo->GCPtrBase = (Desc.Gen.u8BaseHigh2 << 24) | (Desc.Gen.u8BaseHigh1 << 16) | Desc.Gen.u16BaseLow; pSelInfo->fRealMode = false; return VINF_SUCCESS; } /** * Formats a descriptor. * * @param Desc Descriptor to format. * @param Sel Selector number. * @param pszOutput Output buffer. * @param cchOutput Size of output buffer. */ static void selmR3FormatDescriptor(VBOXDESC Desc, RTSEL Sel, char *pszOutput, size_t cchOutput) { /* * Make variable description string. */ static struct { unsigned cch; const char *psz; } const aTypes[32] = { #define STRENTRY(str) { sizeof(str) - 1, str } /* system */ STRENTRY("Reserved0 "), /* 0x00 */ STRENTRY("TSS16Avail "), /* 0x01 */ STRENTRY("LDT "), /* 0x02 */ STRENTRY("TSS16Busy "), /* 0x03 */ STRENTRY("Call16 "), /* 0x04 */ STRENTRY("Task "), /* 0x05 */ STRENTRY("Int16 "), /* 0x06 */ STRENTRY("Trap16 "), /* 0x07 */ STRENTRY("Reserved8 "), /* 0x08 */ STRENTRY("TSS32Avail "), /* 0x09 */ STRENTRY("ReservedA "), /* 0x0a */ STRENTRY("TSS32Busy "), /* 0x0b */ STRENTRY("Call32 "), /* 0x0c */ STRENTRY("ReservedD "), /* 0x0d */ STRENTRY("Int32 "), /* 0x0e */ STRENTRY("Trap32 "), /* 0x0f */ /* non system */ STRENTRY("DataRO "), /* 0x10 */ STRENTRY("DataRO Accessed "), /* 0x11 */ STRENTRY("DataRW "), /* 0x12 */ STRENTRY("DataRW Accessed "), /* 0x13 */ STRENTRY("DataDownRO "), /* 0x14 */ STRENTRY("DataDownRO Accessed "), /* 0x15 */ STRENTRY("DataDownRW "), /* 0x16 */ STRENTRY("DataDownRW Accessed "), /* 0x17 */ STRENTRY("CodeEO "), /* 0x18 */ STRENTRY("CodeEO Accessed "), /* 0x19 */ STRENTRY("CodeER "), /* 0x1a */ STRENTRY("CodeER Accessed "), /* 0x1b */ STRENTRY("CodeConfEO "), /* 0x1c */ STRENTRY("CodeConfEO Accessed "), /* 0x1d */ STRENTRY("CodeConfER "), /* 0x1e */ STRENTRY("CodeConfER Accessed ") /* 0x1f */ #undef SYSENTRY }; #define ADD_STR(psz, pszAdd) do { strcpy(psz, pszAdd); psz += strlen(pszAdd); } while (0) char szMsg[128]; char *psz = &szMsg[0]; unsigned i = Desc.Gen.u1DescType << 4 | Desc.Gen.u4Type; memcpy(psz, aTypes[i].psz, aTypes[i].cch); psz += aTypes[i].cch; if (Desc.Gen.u1Present) ADD_STR(psz, "Present "); else ADD_STR(psz, "Not-Present "); if (Desc.Gen.u1Granularity) ADD_STR(psz, "Page "); if (Desc.Gen.u1DefBig) ADD_STR(psz, "32-bit "); else ADD_STR(psz, "16-bit "); #undef ADD_STR *psz = '\0'; /* * Limit and Base and format the output. */ uint32_t u32Limit = Desc.Gen.u4LimitHigh << 16 | Desc.Gen.u16LimitLow; if (Desc.Gen.u1Granularity) u32Limit = u32Limit << PAGE_SHIFT | PAGE_OFFSET_MASK; uint32_t u32Base = Desc.Gen.u8BaseHigh2 << 24 | Desc.Gen.u8BaseHigh1 << 16 | Desc.Gen.u16BaseLow; RTStrPrintf(pszOutput, cchOutput, "%04x - %08x %08x - base=%08x limit=%08x dpl=%d %s", Sel, Desc.au32[0], Desc.au32[1], u32Base, u32Limit, Desc.Gen.u2Dpl, szMsg); } /** * Dumps a descriptor. * * @param Desc Descriptor to dump. * @param Sel Selector number. * @param pszMsg Message to prepend the log entry with. */ SELMR3DECL(void) SELMR3DumpDescriptor(VBOXDESC Desc, RTSEL Sel, const char *pszMsg) { char szOutput[128]; selmR3FormatDescriptor(Desc, Sel, &szOutput[0], sizeof(szOutput)); Log(("%s: %s\n", pszMsg, szOutput)); NOREF(szOutput[0]); } /** * Display the shadow gdt. * * @param pVM VM Handle. * @param pHlp The info helpers. * @param pszArgs Arguments, ignored. */ static DECLCALLBACK(void) selmR3InfoGdt(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs) { pHlp->pfnPrintf(pHlp, "Shadow GDT (GCAddr=%VGv):\n", MMHyperHC2GC(pVM, pVM->selm.s.paGdtHC)); for (unsigned iGDT = 0; iGDT < SELM_GDT_ELEMENTS; iGDT++) { if (pVM->selm.s.paGdtHC[iGDT].Gen.u1Present) { char szOutput[128]; selmR3FormatDescriptor(pVM->selm.s.paGdtHC[iGDT], iGDT << X86_SEL_SHIFT, &szOutput[0], sizeof(szOutput)); const char *psz = ""; if (iGDT == ((unsigned)pVM->selm.s.SelCS >> X86_SEL_SHIFT)) psz = " HyperCS"; else if (iGDT == ((unsigned)pVM->selm.s.SelDS >> X86_SEL_SHIFT)) psz = " HyperDS"; else if (iGDT == ((unsigned)pVM->selm.s.SelCS64 >> X86_SEL_SHIFT)) psz = " HyperCS64"; else if (iGDT == ((unsigned)pVM->selm.s.SelTSS >> X86_SEL_SHIFT)) psz = " HyperTSS"; else if (iGDT == ((unsigned)pVM->selm.s.SelTSSTrap08 >> X86_SEL_SHIFT)) psz = " HyperTSSTrap08"; pHlp->pfnPrintf(pHlp, "%s%s\n", szOutput, psz); } } } /** * Display the guest gdt. * * @param pVM VM Handle. * @param pHlp The info helpers. * @param pszArgs Arguments, ignored. */ static DECLCALLBACK(void) selmR3InfoGdtGuest(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs) { VBOXGDTR GDTR; CPUMGetGuestGDTR(pVM, &GDTR); RTGCPTR pGDTGC = (RTGCPTR)GDTR.pGdt; unsigned cGDTs = ((unsigned)GDTR.cbGdt + 1) / sizeof(VBOXDESC); pHlp->pfnPrintf(pHlp, "Guest GDT (GCAddr=%VGv limit=%x):\n", pGDTGC, GDTR.cbGdt); for (unsigned iGDT = 0; iGDT < cGDTs; iGDT++, pGDTGC += sizeof(VBOXDESC)) { VBOXDESC GDTE; int rc = PGMPhysReadGCPtr(pVM, &GDTE, pGDTGC, sizeof(GDTE)); if (VBOX_SUCCESS(rc)) { if (GDTE.Gen.u1Present) { char szOutput[128]; selmR3FormatDescriptor(GDTE, iGDT << X86_SEL_SHIFT, &szOutput[0], sizeof(szOutput)); pHlp->pfnPrintf(pHlp, "%s\n", szOutput); } } else if (rc == VERR_PAGE_NOT_PRESENT) { if ((pGDTGC & PAGE_OFFSET_MASK) + sizeof(VBOXDESC) - 1 < sizeof(VBOXDESC)) pHlp->pfnPrintf(pHlp, "%04 - page not present (GCAddr=%VGv)\n", iGDT << X86_SEL_SHIFT, pGDTGC); } else pHlp->pfnPrintf(pHlp, "%04 - read error rc=%Vrc GCAddr=%VGv\n", iGDT << X86_SEL_SHIFT, rc, pGDTGC); } } /** * Display the shadow ldt. * * @param pVM VM Handle. * @param pHlp The info helpers. * @param pszArgs Arguments, ignored. */ static DECLCALLBACK(void) selmR3InfoLdt(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs) { unsigned cLDTs = ((unsigned)pVM->selm.s.cbLdtLimit + 1) >> X86_SEL_SHIFT; PVBOXDESC paLDT = (PVBOXDESC)((char *)pVM->selm.s.HCPtrLdt + pVM->selm.s.offLdtHyper); pHlp->pfnPrintf(pHlp, "Shadow LDT (GCAddr=%VGv limit=%d):\n", pVM->selm.s.GCPtrLdt + pVM->selm.s.offLdtHyper, pVM->selm.s.cbLdtLimit); for (unsigned iLDT = 0; iLDT < cLDTs; iLDT++) { if (paLDT[iLDT].Gen.u1Present) { char szOutput[128]; selmR3FormatDescriptor(paLDT[iLDT], (iLDT << X86_SEL_SHIFT) | X86_SEL_LDT, &szOutput[0], sizeof(szOutput)); pHlp->pfnPrintf(pHlp, "%s\n", szOutput); } } } /** * Display the guest ldt. * * @param pVM VM Handle. * @param pHlp The info helpers. * @param pszArgs Arguments, ignored. */ static DECLCALLBACK(void) selmR3InfoLdtGuest(PVM pVM, PCDBGFINFOHLP pHlp, const char *pszArgs) { RTSEL SelLdt = CPUMGetGuestLDTR(pVM); if (!(SelLdt & X86_SEL_MASK)) { pHlp->pfnPrintf(pHlp, "Guest LDT (Sel=%x): Null-Selector\n", SelLdt); return; } RTGCPTR pLdtGC; unsigned cbLdt; int rc = SELMGetLDTFromSel(pVM, SelLdt, &pLdtGC, &cbLdt); if (VBOX_FAILURE(rc)) { pHlp->pfnPrintf(pHlp, "Guest LDT (Sel=%x): rc=%Vrc\n", SelLdt, rc); return; } pHlp->pfnPrintf(pHlp, "Guest LDT (Sel=%x GCAddr=%VGv limit=%x):\n", SelLdt, pLdtGC, cbLdt); unsigned cLdts = (cbLdt + 1) >> X86_SEL_SHIFT; for (unsigned iLdt = 0; iLdt < cLdts; iLdt++, pLdtGC += sizeof(VBOXDESC)) { VBOXDESC LdtE; int rc = PGMPhysReadGCPtr(pVM, &LdtE, pLdtGC, sizeof(LdtE)); if (VBOX_SUCCESS(rc)) { if (LdtE.Gen.u1Present) { char szOutput[128]; selmR3FormatDescriptor(LdtE, (iLdt << X86_SEL_SHIFT) | X86_SEL_LDT, &szOutput[0], sizeof(szOutput)); pHlp->pfnPrintf(pHlp, "%s\n", szOutput); } } else if (rc == VERR_PAGE_NOT_PRESENT) { if ((pLdtGC & PAGE_OFFSET_MASK) + sizeof(VBOXDESC) - 1 < sizeof(VBOXDESC)) pHlp->pfnPrintf(pHlp, "%04 - page not present (GCAddr=%VGv)\n", (iLdt << X86_SEL_SHIFT) | X86_SEL_LDT, pLdtGC); } else pHlp->pfnPrintf(pHlp, "%04 - read error rc=%Vrc GCAddr=%VGv\n", (iLdt << X86_SEL_SHIFT) | X86_SEL_LDT, rc, pLdtGC); } } /** * Dumps the hypervisor GDT * * @param pVM VM handle. */ SELMR3DECL(void) SELMR3DumpHyperGDT(PVM pVM) { DBGFR3Info(pVM, "gdt", NULL, NULL); } /** * Dumps the hypervisor LDT * * @param pVM VM handle. */ SELMR3DECL(void) SELMR3DumpHyperLDT(PVM pVM) { DBGFR3Info(pVM, "ldt", NULL, NULL); } /** * Dumps the guest GDT * * @param pVM VM handle. */ SELMR3DECL(void) SELMR3DumpGuestGDT(PVM pVM) { DBGFR3Info(pVM, "gdtguest", NULL, NULL); } /** * Dumps the guest LDT * * @param pVM VM handle. */ SELMR3DECL(void) SELMR3DumpGuestLDT(PVM pVM) { DBGFR3Info(pVM, "ldtguest", NULL, NULL); }