[PATCH 3.4 19/24] KVM: Fix buffer overflow in kvm_set_irq()

[Greg Kroah-Hartman]

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Avi Kivity <avi@xxxxxxxxxx>

commit f2ebd422f71cda9c791f76f85d2ca102ae34a1ed upstream.

kvm_set_irq() has an internal buffer of three irq routing entries, allowing
connecting a GSI to three IRQ chips or on MSI.  However setup_routing_entry()
does not properly enforce this, allowing three irqchip routes followed by
an MSI route to overflow the buffer.

Fix by ensuring that an MSI entry is added to an empty list.

Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Cc: Li Zefan <lizefan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 virt/kvm/irq_comm.c |    1 +
 1 file changed, 1 insertion(+)

--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -318,6 +318,7 @@ static int setup_routing_entry(struct kv
 	 */
 	hlist_for_each_entry(ei, n, &rt->map[ue->gsi], link)
 		if (ei->type == KVM_IRQ_ROUTING_MSI ||
+		    ue->type == KVM_IRQ_ROUTING_MSI ||
 		    ue->u.irqchip.irqchip == ei->irqchip.irqchip)
 			return r;
 


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/