KVM: arm/arm64: Fix KVM_VGIC_V3_ADDR_TYPE_REDIST read

commit 94ac0835391efc1a30feda6fc908913ec012951e upstream.

When reading the base address of the a REDIST region
through KVM_VGIC_V3_ADDR_TYPE_REDIST we expect the
redistributor region list to be populated with a single
element.

However list_first_entry() expects the list to be non empty.
Instead we should use list_first_entry_or_null which effectively
returns NULL if the list is empty.

Fixes: dbd9733ab6 ("KVM: arm/arm64: Replace the single rdist region by a list")
Cc: <Stable@vger.kernel.org> # v4.18+
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reported-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210412150034.29185-1-eric.auger@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Eric Auger 2021-04-12 17:00:34 +02:00 committed by Greg Kroah-Hartman
parent 0c2a4178d7
commit 7d266c8a2a
1 changed files with 2 additions and 2 deletions

View File

@ -87,8 +87,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
r = vgic_v3_set_redist_base(kvm, 0, *addr, 0);
goto out;
}
rdreg = list_first_entry(&vgic->rd_regions,
struct vgic_redist_region, list);
rdreg = list_first_entry_or_null(&vgic->rd_regions,
struct vgic_redist_region, list);
if (!rdreg)
addr_ptr = &undef_value;
else