mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-29 07:35:10 +00:00
Code Issues Releases Wiki Activity

KVM: SVM: Truncate GPR value for DR and CR accesses in !64-bit mode

Browse source 
commit 0884335a2e upstream.

Drop bits 63:32 on loads/stores to/from DRs and CRs when the vCPU is not
in 64-bit mode.  The APM states bits 63:32 are dropped for both DRs and
CRs:

  In 64-bit mode, the operand size is fixed at 64 bits without the need
  for a REX prefix. In non-64-bit mode, the operand size is fixed at 32
  bits and the upper 32 bits of the destination are forced to 0.

Fixes: 7ff76d58a9 ("KVM: SVM: enhance MOV CR intercept handler")
Fixes: cae3797a46 ("KVM: SVM: enhance mov DR intercept handler")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210422022128.3464144-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[sudip: manual backport to old file]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sean Christopherson 2021-04-21 19:21:22 -07:00 committed by Greg Kroah-Hartman
parent 0450af01ae
commit 2295e87a5e
1 changed files with 4 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
arch/x86/kvm/svm.c
View file

@ -4057,7 +4057,7 @@ static int cr_interception(struct vcpu_svm *svm)
err = 0;
if (cr >= 16) { /* mov to cr */
cr -= 16;
val = kvm_register_read(&svm->vcpu, reg);
val = kvm_register_readl(&svm->vcpu, reg);
switch (cr) {
case 0:
if (!check_selective_cr0_intercepted(svm, val))
@ -4102,7 +4102,7 @@ static int cr_interception(struct vcpu_svm *svm)
kvm_queue_exception(&svm->vcpu, UD_VECTOR);
return 1;
}
kvm_register_write(&svm->vcpu, reg, val);
kvm_register_writel(&svm->vcpu, reg, val);
}
return kvm_complete_insn_gp(&svm->vcpu, err);
}
@ -4132,13 +4132,13 @@ static int dr_interception(struct vcpu_svm *svm)
if (dr >= 16) { /* mov to DRn */
if (!kvm_require_dr(&svm->vcpu, dr - 16))
return 1;
val = kvm_register_read(&svm->vcpu, reg);
val = kvm_register_readl(&svm->vcpu, reg);
kvm_set_dr(&svm->vcpu, dr - 16, val);
} else {
if (!kvm_require_dr(&svm->vcpu, dr))
return 1;
kvm_get_dr(&svm->vcpu, dr, &val);
kvm_register_write(&svm->vcpu, reg, val);
kvm_register_writel(&svm->vcpu, reg, val);
}
return kvm_skip_emulated_instruction(&svm->vcpu);