Thanks for your comments. One thing I should have pointed out before is that libvirt doesn't have support for the bridge helper yet. I hard coded the qemu options in the domain XML to test this. I'm not sure if that would prevent this patch from getting in or not. On 03/12/2012 02:36 PM, Jamie Strandboge wrote:
On Mon, 2012-03-12 at 09:13 -0400, Corey Bryant wrote:
This patch provides AppArmor policy updates for the QEMU bridge helper. The QEMU bridge helper is a SUID executable exec'd by QEMU that drops capabilities to CAP_NET_ADMIN and adds a tap device to a network bridge. For more details on the helper, please refer to:
http://lists.gnu.org/archive/html/qemu-devel/2012-01/msg03562.html
Signed-off-by: Corey Bryant<coreyb@linux.vnet.ibm.com>
I've not used the helper personally, but the policy makes sense overall though. I do have a few questions:
+ capability setuid, + capability setgid,
I'm assuming these are needed because qemu-bridge-helper drops privileges?
Yes, exactly.
+ capability setpcap,
Can you explain why this capability is needed by qemu-bridge-helper?
This is required to modify the bounding capability set. Here are the calls the helper uses to modify capabilities: capng_clear(CAPNG_SELECT_BOTH); capng_update(CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED, CAP_NET_ADMIN); capng_change_id(getuid(), getgid(), CAPNG_CLEAR_BOUNDING);
+ network inet stream,
I understood why net_admin was needed, but this one is less clear. Why does qemu-bridge-helper need this?
Good question. I'm going to test without this and see if it's necessary. I'm wondering if it's a subset of net_admin, and I may have added this before I added net_admin.
+ /etc/qemu/** r,
I'm not familiar with this directory. What does qemu-bridge-helper need from this directory?
ACL config files can be configured to allow/disallow bridge access to specific users. These files are read from /etc/qemu/.
+ @{PROC}/*/status r,
Is it possible to use this instead: owner @{PROC}/*/status r,
I would imagine this is ok to update with owner. I'll test it out and submit a v2 if there aren't any issues.
Thanks!
Thank you! -- Regards, Corey