KVM: x86: verify MTRR/PAT validity

Do not allow invalid memory types in MTRR/PAT (generating a #GP
otherwise).

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Marcelo Tosatti 2009-06-22 15:27:56 -03:00 committed by Avi Kivity
parent 0ff77873b1
commit d6289b9365
1 changed files with 38 additions and 1 deletions

View File

@ -704,11 +704,48 @@ static bool msr_mtrr_valid(unsigned msr)
return false;
}
static bool valid_pat_type(unsigned t)
{
return t < 8 && (1 << t) & 0xf3; /* 0, 1, 4, 5, 6, 7 */
}
static bool valid_mtrr_type(unsigned t)
{
return t < 8 && (1 << t) & 0x73; /* 0, 1, 4, 5, 6 */
}
static bool mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data)
{
int i;
if (!msr_mtrr_valid(msr))
return false;
if (msr == MSR_IA32_CR_PAT) {
for (i = 0; i < 8; i++)
if (!valid_pat_type((data >> (i * 8)) & 0xff))
return false;
return true;
} else if (msr == MSR_MTRRdefType) {
if (data & ~0xcff)
return false;
return valid_mtrr_type(data & 0xff);
} else if (msr >= MSR_MTRRfix64K_00000 && msr <= MSR_MTRRfix4K_F8000) {
for (i = 0; i < 8 ; i++)
if (!valid_mtrr_type((data >> (i * 8)) & 0xff))
return false;
return true;
}
/* variable MTRRs */
return valid_mtrr_type(data & 0xff);
}
static int set_msr_mtrr(struct kvm_vcpu *vcpu, u32 msr, u64 data)
{
u64 *p = (u64 *)&vcpu->arch.mtrr_state.fixed_ranges;
if (!msr_mtrr_valid(msr))
if (!mtrr_valid(vcpu, msr, data))
return 1;
if (msr == MSR_MTRRdefType) {