Esempio n. 1
0
/**
 * \#PF Virtual Handler callback for Guest write access to the VBox shadow IDT.
 *
 * @returns VBox status code (appropriate for trap handling and GC return).
 * @param   pVM         VM Handle.
 * @param   uErrorCode   CPU Error code.
 * @param   pRegFrame   Trap register frame.
 * @param   pvFault     The fault address (cr2).
 * @param   pvRange     The base address of the handled virtual range.
 * @param   offRange    The offset of the access into this range.
 *                      (If it's a EIP range this is the EIP, if not it's pvFault.)
 */
VMMRCDECL(int) trpmRCShadowIDTWriteHandler(PVM pVM, RTGCUINT uErrorCode, PCPUMCTXCORE pRegFrame, RTGCPTR pvFault, RTGCPTR pvRange, uintptr_t offRange)
{
    PVMCPU pVCpu = VMMGetCpu0(pVM);
    LogRel(("FATAL ERROR: trpmRCShadowIDTWriteHandler: eip=%08X pvFault=%RGv pvRange=%08X\r\n", pRegFrame->eip, pvFault, pvRange));

    /* If we ever get here, then the guest has executed an sidt instruction that we failed to patch. In theory this could be very bad, but
     * there are nasty applications out there that install device drivers that mess with the guest's IDT. In those cases, it's quite ok
     * to simply ignore the writes and pretend success.
     */
    RTGCPTR PC;
    int rc = SELMValidateAndConvertCSAddr(pVM, pRegFrame->eflags, pRegFrame->ss, pRegFrame->cs, &pRegFrame->csHid,
                                          (RTGCPTR)pRegFrame->eip, &PC);
    if (rc == VINF_SUCCESS)
    {
        DISCPUSTATE Cpu;
        uint32_t    cbOp;
        rc = EMInterpretDisasOneEx(pVM, pVCpu, (RTGCUINTPTR)PC, pRegFrame, &Cpu, &cbOp);
        if (rc == VINF_SUCCESS)
        {
            /* Just ignore the write. */
            pRegFrame->eip += Cpu.opsize;
            return VINF_SUCCESS;
        }
    }

    return VERR_TRPM_SHADOW_IDT_WRITE;
}
Esempio n. 2
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/**
 * \#GP (General Protection Fault) handler.
 *
 * @returns VBox status code.
 *          VINF_SUCCESS means we completely handled this trap,
 *          other codes are passed execution to host context.
 *
 * @param   pVM         Pointer to the VM.
 * @param   pTrpmCpu    Pointer to TRPMCPU data (within VM).
 * @param   pRegFrame   Pointer to the register frame for the trap.
 */
static int trpmGCTrap0dHandler(PVM pVM, PTRPMCPU pTrpmCpu, PCPUMCTXCORE pRegFrame)
{
    LogFlow(("trpmGCTrap0dHandler: cs:eip=%RTsel:%08RX32 uErr=%RGv\n", pRegFrame->cs.Sel, pRegFrame->eip, pTrpmCpu->uActiveErrorCode));
    PVMCPU  pVCpu = TRPMCPU_2_VMCPU(pTrpmCpu);

    /*
     * Convert and validate CS.
     */
    STAM_PROFILE_START(&pVM->trpm.s.StatTrap0dDisasm, a);
    RTGCPTR PC;
    uint32_t cBits;
    int rc = SELMValidateAndConvertCSAddrGCTrap(pVCpu, pRegFrame->eflags, pRegFrame->ss.Sel, pRegFrame->cs.Sel,
                                                pRegFrame->rip, &PC, &cBits);
    if (RT_FAILURE(rc))
    {
        Log(("trpmGCTrap0dHandler: Failed to convert %RTsel:%RX32 (cpl=%d) - rc=%Rrc !!\n",
             pRegFrame->cs.Sel, pRegFrame->eip, pRegFrame->ss.Sel & X86_SEL_RPL, rc));
        STAM_PROFILE_STOP(&pVM->trpm.s.StatTrap0dDisasm, a);
        return trpmGCExitTrap(pVM, pVCpu, VINF_EM_RAW_EMULATE_INSTR, pRegFrame);
    }

    /*
     * Disassemble the instruction.
     */
    DISCPUSTATE Cpu;
    uint32_t    cbOp;
    rc = EMInterpretDisasOneEx(pVM, pVCpu, PC, pRegFrame, &Cpu, &cbOp);
    if (RT_FAILURE(rc))
    {
        AssertMsgFailed(("DISCoreOneEx failed to PC=%RGv rc=%Rrc\n", PC, rc));
        STAM_PROFILE_STOP(&pVM->trpm.s.StatTrap0dDisasm, a);
        return trpmGCExitTrap(pVM, pVCpu, VINF_EM_RAW_EMULATE_INSTR, pRegFrame);
    }
    STAM_PROFILE_STOP(&pVM->trpm.s.StatTrap0dDisasm, a);

    /*
     * Optimize RDTSC traps.
     * Some guests (like Solaris) are using RDTSC all over the place and
     * will end up trapping a *lot* because of that.
     *
     * Note: it's no longer safe to access the instruction opcode directly due to possible stale code TLB entries
     */
    if (Cpu.pCurInstr->uOpcode == OP_RDTSC)
        return trpmGCTrap0dHandlerRdTsc(pVM, pVCpu, pRegFrame);

    /*
     * Deal with I/O port access.
     */
    if (    pVCpu->trpm.s.uActiveErrorCode == 0
        &&  (Cpu.pCurInstr->fOpType & DISOPTYPE_PORTIO))
    {
        VBOXSTRICTRC rcStrict = IOMRCIOPortHandler(pVM, pRegFrame, &Cpu);
        if (IOM_SUCCESS(rcStrict))
            pRegFrame->rip += cbOp;
        rc = VBOXSTRICTRC_TODO(rcStrict);
        return trpmGCExitTrap(pVM, pVCpu, rc, pRegFrame);
    }

    /*
     * Deal with Ring-0 (privileged instructions)
     */
    if (    (pRegFrame->ss.Sel & X86_SEL_RPL) <= 1
        &&  !pRegFrame->eflags.Bits.u1VM)
        return trpmGCTrap0dHandlerRing0(pVM, pVCpu, pRegFrame, &Cpu, PC);

    /*
     * Deal with Ring-3 GPs.
     */
    if (!pRegFrame->eflags.Bits.u1VM)
        return trpmGCTrap0dHandlerRing3(pVM, pVCpu, pRegFrame, &Cpu, PC);

    /*
     * Deal with v86 code.
     *
     * We always set IOPL to zero which makes e.g. pushf fault in V86
     * mode. The guest might use IOPL=3 and therefore not expect a #GP.
     * Simply fall back to the recompiler to emulate this instruction if
     * that's the case. To get the correct we must use CPUMRawGetEFlags.
     */
    X86EFLAGS eflags;
    eflags.u32 = CPUMRawGetEFlags(pVCpu); /* Get the correct value. */
    Log3(("TRPM #GP V86: cs:eip=%04x:%08x IOPL=%d efl=%08x\n", pRegFrame->cs.Sel, pRegFrame->eip, eflags.Bits.u2IOPL, eflags.u));
    if (eflags.Bits.u2IOPL != 3)
    {
        Assert(eflags.Bits.u2IOPL == 0);

        rc = TRPMForwardTrap(pVCpu, pRegFrame, 0xD, 0, TRPM_TRAP_HAS_ERRORCODE, TRPM_TRAP, 0xd);
        Assert(rc == VINF_EM_RAW_GUEST_TRAP);
        return trpmGCExitTrap(pVM, pVCpu, rc, pRegFrame);
    }
    return trpmGCExitTrap(pVM, pVCpu, VINF_EM_RAW_EMULATE_INSTR, pRegFrame);
}
Esempio n. 3
0
/**
 * Trap handler for illegal opcode fault (\#UD).
 *
 * @returns VBox status code.
 *          VINF_SUCCESS means we completely handled this trap,
 *          other codes are passed execution to host context.
 *
 * @param   pTrpmCpu    Pointer to TRPMCPU data (within VM).
 * @param   pRegFrame   Pointer to the register frame for the trap.
 * @internal
 */
DECLASM(int) TRPMGCTrap06Handler(PTRPMCPU pTrpmCpu, PCPUMCTXCORE pRegFrame)
{
    LogFlow(("TRPMGC06: %04x:%08x efl=%x\n", pRegFrame->cs.Sel, pRegFrame->eip, pRegFrame->eflags.u32));
    PVM     pVM   = TRPMCPU_2_VM(pTrpmCpu);
    PVMCPU  pVCpu = TRPMCPU_2_VMCPU(pTrpmCpu);
    int     rc;
    PGMRZDynMapStartAutoSet(pVCpu);

    if (CPUMGetGuestCPL(pVCpu) == 0)
    {
        /*
         * Decode the instruction.
         */
        RTGCPTR PC;
        rc = SELMValidateAndConvertCSAddr(pVCpu, pRegFrame->eflags, pRegFrame->ss.Sel, pRegFrame->cs.Sel, &pRegFrame->cs,
                                          pRegFrame->rip, &PC);
        if (RT_FAILURE(rc))
        {
            Log(("TRPMGCTrap06Handler: Failed to convert %RTsel:%RX32 (cpl=%d) - rc=%Rrc !!\n", pRegFrame->cs.Sel, pRegFrame->eip, pRegFrame->ss.Sel & X86_SEL_RPL, rc));
            rc = trpmGCExitTrap(pVM, pVCpu, VINF_EM_RAW_GUEST_TRAP, pRegFrame);
            Log6(("TRPMGC06: %Rrc (%04x:%08x) (SELM)\n", rc, pRegFrame->cs.Sel, pRegFrame->eip));
            return rc;
        }

        DISCPUSTATE Cpu;
        uint32_t    cbOp;
        rc = EMInterpretDisasOneEx(pVM, pVCpu, (RTGCUINTPTR)PC, pRegFrame, &Cpu, &cbOp);
        if (RT_FAILURE(rc))
        {
            rc = trpmGCExitTrap(pVM, pVCpu, VINF_EM_RAW_EMULATE_INSTR, pRegFrame);
            Log6(("TRPMGC06: %Rrc (%04x:%08x) (EM)\n", rc, pRegFrame->cs.Sel, pRegFrame->eip));
            return rc;
        }

        /*
         * UD2 in a patch?
         * Note! PATMGCHandleIllegalInstrTrap doesn't always return.
         */
        if (    Cpu.pCurInstr->uOpcode == OP_ILLUD2
            &&  PATMIsPatchGCAddr(pVM, pRegFrame->eip))
        {
            LogFlow(("TRPMGCTrap06Handler: -> PATMRCHandleIllegalInstrTrap\n"));
            rc = PATMRCHandleIllegalInstrTrap(pVM, pRegFrame);
            /** @todo  These tests are completely unnecessary, should just follow the
             *         flow and return at the end of the function. */
            if (    rc == VINF_SUCCESS
                ||  rc == VINF_EM_RAW_EMULATE_INSTR
                ||  rc == VINF_PATM_DUPLICATE_FUNCTION
                ||  rc == VINF_PATM_PENDING_IRQ_AFTER_IRET
                ||  rc == VINF_EM_RESCHEDULE)
            {
                rc = trpmGCExitTrap(pVM, pVCpu, rc, pRegFrame);
                Log6(("TRPMGC06: %Rrc (%04x:%08x) (PATM)\n", rc, pRegFrame->cs.Sel, pRegFrame->eip));
                return rc;
            }
        }
        /*
         * Speed up dtrace and don't entrust invalid lock sequences to the recompiler.
         */
        else if (Cpu.fPrefix & DISPREFIX_LOCK)
        {
            Log(("TRPMGCTrap06Handler: pc=%08x op=%d\n", pRegFrame->eip, Cpu.pCurInstr->uOpcode));
#ifdef DTRACE_EXPERIMENT /** @todo fix/remove/permanent-enable this when DIS/PATM handles invalid lock sequences. */
            Assert(!PATMIsPatchGCAddr(pVM, pRegFrame->eip));
            rc = TRPMForwardTrap(pVCpu, pRegFrame, 0x6, 0, TRPM_TRAP_NO_ERRORCODE, TRPM_TRAP, 0x6);
            Assert(rc == VINF_EM_RAW_GUEST_TRAP);
#else
            rc = VINF_EM_RAW_EMULATE_INSTR;
#endif
        }
        /*
         * Handle MONITOR - it causes an #UD exception instead of #GP when not executed in ring 0.
         */
        else if (Cpu.pCurInstr->uOpcode == OP_MONITOR)
        {
            LogFlow(("TRPMGCTrap06Handler: -> EMInterpretInstructionCPU\n"));
            rc = EMInterpretInstructionDisasState(pVCpu, &Cpu, pRegFrame, PC, EMCODETYPE_SUPERVISOR);
        }
        /* Never generate a raw trap here; it might be an instruction, that requires emulation. */
        else
        {
            LogFlow(("TRPMGCTrap06Handler: -> VINF_EM_RAW_EMULATE_INSTR\n"));
            rc = VINF_EM_RAW_EMULATE_INSTR;
        }
    }
    else
    {
        LogFlow(("TRPMGCTrap06Handler: -> TRPMForwardTrap\n"));
        rc = TRPMForwardTrap(pVCpu, pRegFrame, 0x6, 0, TRPM_TRAP_NO_ERRORCODE, TRPM_TRAP, 0x6);
        Assert(rc == VINF_EM_RAW_GUEST_TRAP);
    }

    rc = trpmGCExitTrap(pVM, pVCpu, rc, pRegFrame);
    Log6(("TRPMGC06: %Rrc (%04x:%08x)\n", rc, pRegFrame->cs.Sel, pRegFrame->eip));
    return rc;
}