Commit 25597f64 authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini

Revert "KVM: x86: work around leak of uninitialized stack contents"

handle_vmptrst()/handle_vmread() stopped injecting #PF unconditionally
and switched to nested_vmx_handle_memory_failure() which just kills the
guest with KVM_EXIT_INTERNAL_ERROR in case of MMIO access, zeroing
'exception' in kvm_write_guest_virt_system() is not needed anymore.

This reverts commit 541ab2ae.
Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200605115906.532682-2-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 7a35e515
...@@ -5647,13 +5647,6 @@ int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val, ...@@ -5647,13 +5647,6 @@ int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val,
/* kvm_write_guest_virt_system can pull in tons of pages. */ /* kvm_write_guest_virt_system can pull in tons of pages. */
vcpu->arch.l1tf_flush_l1d = true; vcpu->arch.l1tf_flush_l1d = true;
/*
* FIXME: this should call handle_emulation_failure if X86EMUL_IO_NEEDED
* is returned, but our callers are not ready for that and they blindly
* call kvm_inject_page_fault. Ensure that they at least do not leak
* uninitialized kernel stack memory into cr2 and error code.
*/
memset(exception, 0, sizeof(*exception));
return kvm_write_guest_virt_helper(addr, val, bytes, vcpu, return kvm_write_guest_virt_helper(addr, val, bytes, vcpu,
PFERR_WRITE_MASK, exception); PFERR_WRITE_MASK, exception);
} }
......
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