KVM: arm/arm64: vgic-its: Preserve the revious read from the pending table

commit 64afe6e9eb4841f35317da4393de21a047a883b3 upstream.

The current pending table parsing code assumes that we keep the
previous read of the pending bits, but keep that variable in
the current block, making sure it is discarded on each loop.

We end-up using whatever is on the stack. Who knows, it might
just be the right thing...

Fixes: 33d3bc9556a7d ("KVM: arm64: vgic-its: Read initial LPI pending table")
Cc: stable@vger.kernel.org # 4.8
Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index ebcaf4641d2b7c1f69378c83f61a1afee0b468cf..31f5625079157254ecb5a073ced2cda1408402e5 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -322,6 +322,7 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu)
        int ret = 0;
        u32 *intids;
        int nr_irqs, i;
+       u8 pendmask;
 
        nr_irqs = vgic_copy_lpi_list(vcpu->kvm, &intids);
        if (nr_irqs < 0)
@@ -329,7 +330,6 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu)
 
        for (i = 0; i < nr_irqs; i++) {
                int byte_offset, bit_nr;
-               u8 pendmask;
 
                byte_offset = intids[i] / BITS_PER_BYTE;
                bit_nr = intids[i] % BITS_PER_BYTE;