[libvirt] [PATCH] qemu: Check for down limit of SLIRP prefix too

[Michal Privoznik]

https://bugzilla.redhat.com/show_bug.cgi?id=1515533

We're already checking if IPv4 prefix isn't too long. But we are
not checking if it isn't too short. QEMU supports prefixes longer
than 4 (including). I haven't find anything similar related to
IPv6 in qemu sources.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_domain.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index df433c2f0..4fc4db68b 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -3744,6 +3744,12 @@ qemuDomainDeviceDefValidateNetwork(const virDomainNetDef *net)
                                    _("prefix too long"));
                     return -1;
                 }
+
+                if (ip->prefix < 4) {
+                    virReportError(VIR_ERR_XML_ERROR, "%s",
+                                   _("prefix too short"));
+                    return -1;
+                }
             }
 
             if (VIR_SOCKET_ADDR_IS_FAMILY(&ip->address, AF_INET6)) {
-- 
2.13.6