From 61552367b2ce5e9bea6b6af670ec80aea386f34e Mon Sep 17 00:00:00 2001 From: Mark McLoughlin Date: Mon, 1 Dec 2008 13:57:48 +0000 Subject: KVM: add KVM_USERSPACE_IRQ_SOURCE_ID assertions Make sure kvm_request_irq_source_id() never returns KVM_USERSPACE_IRQ_SOURCE_ID. Likewise, check that kvm_free_irq_source_id() never accepts KVM_USERSPACE_IRQ_SOURCE_ID. Signed-off-by: Mark McLoughlin Signed-off-by: Avi Kivity --- virt/kvm/irq_comm.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'virt') diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c index db75045f22f..aa5d1e5c497 100644 --- a/virt/kvm/irq_comm.c +++ b/virt/kvm/irq_comm.c @@ -72,11 +72,15 @@ int kvm_request_irq_source_id(struct kvm *kvm) unsigned long *bitmap = &kvm->arch.irq_sources_bitmap; int irq_source_id = find_first_zero_bit(bitmap, sizeof(kvm->arch.irq_sources_bitmap)); + if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) { printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n"); - irq_source_id = -EFAULT; - } else - set_bit(irq_source_id, bitmap); + return -EFAULT; + } + + ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID); + set_bit(irq_source_id, bitmap); + return irq_source_id; } @@ -84,7 +88,9 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id) { int i; - if (irq_source_id <= 0 || + ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID); + + if (irq_source_id < 0 || irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) { printk(KERN_ERR "kvm: IRQ source ID out of range!\n"); return; -- cgit v1.2.3