diff options
| author | Denis Valeev <lemniscattaden@gmail.com> | 2022-01-22 23:13:57 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-01-26 20:14:59 +0300 |
| commit | 47c28d436f409f5b009dc82bd82d4971088aa391 (patch) | |
| tree | 198aafde66380607f17602b1b549876f752ad7f3 /arch | |
| parent | 1ffce0924a8c86cf0590c039cd5f5c9375d32e9b (diff) | |
| download | linux-47c28d436f409f5b009dc82bd82d4971088aa391.tar.xz | |
KVM: x86: nSVM: skip eax alignment check for non-SVM instructions
The bug occurs on #GP triggered by VMware backdoor when eax value is
unaligned. eax alignment check should not be applied to non-SVM
instructions because it leads to incorrect omission of the instructions
emulation.
Apply the alignment check only to SVM instructions to fix.
Fixes: d1cba6c92237 ("KVM: x86: nSVM: test eax for 4K alignment for GP errata workaround")
Signed-off-by: Denis Valeev <lemniscattaden@gmail.com>
Message-Id: <Yexlhaoe1Fscm59u@q>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 6d31d357a83b..ec05f8bfc21b 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2091,10 +2091,6 @@ static int gp_interception(struct kvm_vcpu *vcpu) if (error_code) goto reinject; - /* All SVM instructions expect page aligned RAX */ - if (svm->vmcb->save.rax & ~PAGE_MASK) - goto reinject; - /* Decode the instruction for usage later */ if (x86_decode_emulated_instruction(vcpu, 0, NULL, 0) != EMULATION_OK) goto reinject; @@ -2112,8 +2108,13 @@ static int gp_interception(struct kvm_vcpu *vcpu) if (!is_guest_mode(vcpu)) return kvm_emulate_instruction(vcpu, EMULTYPE_VMWARE_GP | EMULTYPE_NO_DECODE); - } else + } else { + /* All SVM instructions expect page aligned RAX */ + if (svm->vmcb->save.rax & ~PAGE_MASK) + goto reinject; + return emulate_svm_instr(vcpu, opcode); + } reinject: kvm_queue_exception_e(vcpu, GP_VECTOR, error_code); |