From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.15 161/207] KVM: SEV: initialize regions_list of a mirror VM
Date:   Mon,  6 Dec 2021 15:56:55 +0100
Message-Id: <20211206145615.848113291@linuxfoundation.org>
In-Reply-To: <20211206145610.172203682@linuxfoundation.org>
References: <20211206145610.172203682@linuxfoundation.org>
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From: Paolo Bonzini <pbonzini@redhat.com>

[ 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@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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