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From f97340639134f6fbafb00f87898b4abddf9b4d4d Mon Sep 17 00:00:00 2001
Message-Id: <f97340639134f6fbafb00f87898b4abddf9b4d4d@dist-git>
From: "Daniel P. Berrange" <berrange@redhat.com>
Date: Tue, 18 Feb 2014 15:45:32 -0700
Subject: [PATCH] Fix path used for USB device attach with LXC

https://bugzilla.redhat.com/show_bug.cgi?id=1045643
prereq of CVE-2013-6456

The LXC code missed the 'usb' component out of the path
/dev/bus/usb/$BUSNUM/$DEVNUM, so it failed to actually
setup cgroups for the device. This was in fact lucky
because the call to virLXCSetupHostUsbDeviceCgroup
was also mistakenly passing '&priv->cgroup' instead of
just 'priv->cgroup'. So once the path is fixed, libvirtd
would then crash trying to access the bogus virCgroupPtr
pointer. This would have been a security issue, were it
not for the bogus path preventing the pointer reference
being reached.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit c3648972222d4eb056e6e667c193ba56a7aa3557)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/lxc/lxc_driver.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
index 48456ad..63c545c 100644
--- a/src/lxc/lxc_driver.c
+++ b/src/lxc/lxc_driver.c
@@ -3338,7 +3338,7 @@ lxcDomainAttachDeviceHostdevSubsysUSBLive(virLXCDriverPtr driver,
                     (unsigned long long)priv->initpid) < 0)
         goto cleanup;
 
-    if (virAsprintf(&dstdir, "%s/dev/bus/%03d",
+    if (virAsprintf(&dstdir, "%s/dev/bus/usb/%03d",
                     vroot,
                     def->source.subsys.u.usb.bus) < 0)
         goto cleanup;
@@ -3403,7 +3403,7 @@ lxcDomainAttachDeviceHostdevSubsysUSBLive(virLXCDriverPtr driver,
 
     if (virUSBDeviceFileIterate(usb,
                                 virLXCSetupHostUsbDeviceCgroup,
-                                &priv->cgroup) < 0)
+                                priv->cgroup) < 0)
         goto cleanup;
 
     ret = 0;
-- 
1.9.0