From 7cc101ce0e8e1929f6573c3bee3ec2e287304513 Mon Sep 17 00:00:00 2001 From: Laine Stump Date: Mon, 14 Mar 2011 11:15:19 -0400 Subject: [PATCH] audit: eliminate potential null pointer deref when auditing macvtap devices The newly added call to qemuAuditNetDevice in qemuPhysIfaceConnect was assuming that res_ifname (the name of the macvtap device) was always valid, but this isn't the case. If openMacvtapTap fails, it always returns NULL, which would result in a segv. Since the audit log only needs a record of devices that are actually sent to qemu, and a failure to open the macvtap device means that no device will be sent to qemu, we can solve this problem by only doing the audit if openMacvtapTap is successful (in which case res_ifname is guaranteed valid). --- src/qemu/qemu_command.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 8ca656afee..72f55d001c 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -128,8 +128,8 @@ qemuPhysIfaceConnect(virDomainDefPtr def, net->data.direct.mode, vnet_hdr, def->uuid, &net->data.direct.virtPortProfile, &res_ifname, vmop); - qemuAuditNetDevice(def, net, res_ifname, rc >= 0); if (rc >= 0) { + qemuAuditNetDevice(def, net, res_ifname, true); VIR_FREE(net->ifname); net->ifname = res_ifname; }