| Message ID | 20181012180429.259916-1-jmattson@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] kvm: x86: Bounds-check argument to x86_exception_has_error_code | expand |
On Fri, Oct 12, 2018 at 11:04:28AM -0700, Jim Mattson wrote: > x86_exception_has_error_code should deterministically return false if > its operand is greater than or equal to 32. > > Fixes: 0447378a4a793 ("kvm: vmx: Nested VM-entry prereqs for event inj.") > Cc: Marc Orr <marcorr@google.com> > Signed-off-by: Jim Mattson <jmattson@google.com> > --- > arch/x86/kvm/x86.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h > index 67b9568613f3..b7890b248e64 100644 > --- a/arch/x86/kvm/x86.h > +++ b/arch/x86/kvm/x86.h > @@ -116,7 +116,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector) > BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) | > BIT(PF_VECTOR) | BIT(AC_VECTOR); > > - return (1U << vector) & exception_has_error_code; > + return vector < 32 && (1U << vector) & exception_has_error_code; This feels like it should be a WARN_ON, i.e. KVM should be ensuring the vector itself is valid prior to querying whether or not it should have an error code. > } > > static inline bool mmu_is_nested(struct kvm_vcpu *vcpu) > -- > 2.19.1.331.ge82ca0e54c-goog >
On Fri, Oct 12, 2018 at 1:07 PM, Sean Christopherson <sean.j.christopherson@intel.com> wrote: > This feels like it should be a WARN_ON, i.e. KVM should be ensuring > the vector itself is valid prior to querying whether or not it should > have an error code. I'll add a WARN_ON in v2.
On 10/12/2018 11:04 AM, Jim Mattson wrote: > x86_exception_has_error_code should deterministically return false if > its operand is greater than or equal to 32. > > Fixes: 0447378a4a793 ("kvm: vmx: Nested VM-entry prereqs for event inj.") > Cc: Marc Orr <marcorr@google.com> > Signed-off-by: Jim Mattson <jmattson@google.com> > --- > arch/x86/kvm/x86.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h > index 67b9568613f3..b7890b248e64 100644 > --- a/arch/x86/kvm/x86.h > +++ b/arch/x86/kvm/x86.h > @@ -116,7 +116,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector) > BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) | > BIT(PF_VECTOR) | BIT(AC_VECTOR); > > - return (1U << vector) & exception_has_error_code; > + return vector < 32 && (1U << vector) & exception_has_error_code; > } > > static inline bool mmu_is_nested(struct kvm_vcpu *vcpu) Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
On Fri, Oct 12, 2018 at 3:59 PM Krish Sadhukhan <krish.sadhukhan@oracle.com> wrote: > > > > On 10/12/2018 11:04 AM, Jim Mattson wrote: > > x86_exception_has_error_code should deterministically return false if > > its operand is greater than or equal to 32. > > > > Fixes: 0447378a4a793 ("kvm: vmx: Nested VM-entry prereqs for event inj.") > > Cc: Marc Orr <marcorr@google.com> > > Signed-off-by: Jim Mattson <jmattson@google.com> > > --- > > arch/x86/kvm/x86.h | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h > > index 67b9568613f3..b7890b248e64 100644 > > --- a/arch/x86/kvm/x86.h > > +++ b/arch/x86/kvm/x86.h > > @@ -116,7 +116,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector) > > BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) | > > BIT(PF_VECTOR) | BIT(AC_VECTOR); > > > > - return (1U << vector) & exception_has_error_code; > > + return vector < 32 && (1U << vector) & exception_has_error_code; > > } > > > > static inline bool mmu_is_nested(struct kvm_vcpu *vcpu) > > Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Reviewed-by: Marc Orr <marcorr@google.com>
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 67b9568613f3..b7890b248e64 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -116,7 +116,7 @@ static inline bool x86_exception_has_error_code(unsigned int vector) BIT(NP_VECTOR) | BIT(SS_VECTOR) | BIT(GP_VECTOR) | BIT(PF_VECTOR) | BIT(AC_VECTOR); - return (1U << vector) & exception_has_error_code; + return vector < 32 && (1U << vector) & exception_has_error_code; } static inline bool mmu_is_nested(struct kvm_vcpu *vcpu)
x86_exception_has_error_code should deterministically return false if its operand is greater than or equal to 32. Fixes: 0447378a4a793 ("kvm: vmx: Nested VM-entry prereqs for event inj.") Cc: Marc Orr <marcorr@google.com> Signed-off-by: Jim Mattson <jmattson@google.com> --- arch/x86/kvm/x86.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)