KVM: arm64: vgic-its: Fix memory leak on the error path of vgic_add_lpi()

If we're going to fail out the vgic_add_lpi(), let's make sure the
allocated vgic_irq memory is also freed. Though it seems that both
cases are unlikely to fail.

Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200414030349.625-3-yuzenghui@huawei.com

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index d53d34a..c012a52 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -96,14 +96,21 @@ out_unlock:
         * We "cache" the configuration table entries in our struct vgic_irq's.
         * However we only have those structs for mapped IRQs, so we read in
         * the respective config data from memory here upon mapping the LPI.
+        *
+        * Should any of these fail, behave as if we couldn't create the LPI
+        * by dropping the refcount and returning the error.
         */
        ret = update_lpi_config(kvm, irq, NULL, false);
-       if (ret)
+       if (ret) {
+               vgic_put_irq(kvm, irq);
                return ERR_PTR(ret);
+       }
 
        ret = vgic_v3_lpi_sync_pending_status(kvm, irq);
-       if (ret)
+       if (ret) {
+               vgic_put_irq(kvm, irq);
                return ERR_PTR(ret);
+       }
 
        return irq;
 }