[PATCH 5.15 161/207] KVM: SEV: initialize regions_list of a mirror VM

From: Greg Kroah-Hartman
Date: Mon Dec 06 2021 - 11:00:05 EST


From: Paolo Bonzini <pbonzini@xxxxxxxxxx>

[ Upstream commit 2b347a387811cb4aa7bcdb96e9203c5019a6fb41 ]

This was broken before the introduction of KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM,
but technically harmless because the region list was unused for a mirror
VM. However, it is untidy and it now causes a NULL pointer access when
attempting to move the encryption context of a mirror VM.

Fixes: 54526d1fd593 ("KVM: x86: Support KVM VMs sharing SEV context")
Message-Id: <20211123005036.2954379-7-pbonzini@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/kvm/svm/sev.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index ff19ce0780fea..ca0effb79eab9 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1805,6 +1805,7 @@ int svm_vm_copy_asid_from(struct kvm *kvm, unsigned int source_fd)
mirror_sev->fd = source_sev.fd;
mirror_sev->es_active = source_sev.es_active;
mirror_sev->handle = source_sev.handle;
+ INIT_LIST_HEAD(&mirror_sev->regions_list);
/*
* Do not copy ap_jump_table. Since the mirror does not share the same
* KVM contexts as the original, and they may have different
--
2.33.0