This patch checks that the user calling ioctl() to create, delete, or
modify bridges has the CAP_NET_ADMIN capability. This prevents
unpriviledged users from modifying the bridge configuration through
brcompatd. The checks are actually the same performed in
net/bridge/br_ioctl.c by the Linux kernel.
---
Unprivileged users can create or destroy bridges when brcompatd is
running. I believe this is a serious security risk. I tested it only on
Fedora 12 with a Xenified 2.6.32 kernel, but the change is small enough
that there shouldn't be any problem with any version of Linux.
datapath/brcompat.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/datapath/brcompat.c b/datapath/brcompat.c
index 3e84011..2113eae 100644
--- a/datapath/brcompat.c
+++ b/datapath/brcompat.c
@@ -84,6 +84,9 @@ static int brc_add_del_bridge(char __user *uname, int
add)
struct sk_buff *request;
char name[IFNAMSIZ];
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
if (copy_from_user(name, uname, IFNAMSIZ))
return -EFAULT;
@@ -196,6 +199,9 @@ static int brc_add_del_port(struct net_device *dev,
int port_ifindex, int add)
struct net_device *port;
int err;
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
port = __dev_get_by_index(&init_net, port_ifindex);
if (!port)
return -EINVAL;
--
1.6.6.1
--
Vivien Bernet-Rollande
So Privé Cloud Computing
http://www.soprive.net/
_______________________________________________
discuss mailing list
[email protected]
http://openvswitch.org/mailman/listinfo/discuss_openvswitch.org