[libvirt] [PATCH v2] virt-aa-helper: generate rules for gl enabled graphics devices

[Erik Skultety]

On Tue, Jan 22, 2019 at 11:30:50AM +0100, Christian Ehrhardt wrote:
> This adds the virt-aa-helper support for gl enabled graphics devices to
> generate rules for the needed rendernode paths.
>
> Example in domain xml:
> <graphics type='spice'>
>   <gl enable='yes' rendernode='/dev/dri/bar'/>
> </graphics>
>
> results in:
>   "/dev/dri/bar" rw,
>
> Special cases are:
> - multiple devices with rendernodes -> all are added
> - non explicit rendernodes -> follow recently added virHostGetDRMRenderNode
> - rendernode without opengl (in egl-headless for example) -> still add
>   the node
>
> Updates in V2:
> - avoid leaking rendernode
> - logically group patch hunks
> - drop base /dev/dri access
> - simplify detection of the need for a default rendernode
> - add tests in tests/virt-aa-helper-test
> - rebased to recent master

^This is irrelevant to the git history, so should be dropped before pushing

>
> Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1757085
>
> Signed-off-by: Christian Ehrhardt <christian.ehrhardt at canonical.com>
> ---
>  src/security/virt-aa-helper.c | 12 ++++++++++++
>  tests/virt-aa-helper-test     |  6 ++++++
>  2 files changed, 18 insertions(+)
>
> diff --git a/src/security/virt-aa-helper.c b/src/security/virt-aa-helper.c
> index 64a425671d..a84dd5a8c9 100644
> --- a/src/security/virt-aa-helper.c
> +++ b/src/security/virt-aa-helper.c
> @@ -1062,6 +1062,18 @@ get_files(vahControl * ctl)
>      for (i = 0; i < ctl->def->ngraphics; i++) {
>          virDomainGraphicsDefPtr graphics = ctl->def->graphics[i];
>          size_t n;
> +        const char *rendernode = virDomainGraphicsGetRenderNode(graphics);
> +
> +        if (rendernode)
> +            vah_add_file(&buf, rendernode, "rw");
> +        else
> +            if (virDomainGraphicsNeedsAutoRenderNode(graphics)) {
> +                char * defaultRenderNode = virHostGetDRMRenderNode();
> +                if (defaultRenderNode) {
> +                    vah_add_file(&buf, defaultRenderNode, "rw");
> +                    VIR_FREE(defaultRenderNode);
> +            }
> +        }

Minor guideline nitpick about curly braces around complex bodies, with the
following squashed in:

diff --git a/src/security/virt-aa-helper.c b/src/security/virt-aa-helper.c
index a84dd5a8c9..78666db4f8 100644
--- a/src/security/virt-aa-helper.c
+++ b/src/security/virt-aa-helper.c
@@ -1064,14 +1064,15 @@ get_files(vahControl * ctl)
         size_t n;
         const char *rendernode = virDomainGraphicsGetRenderNode(graphics);

-        if (rendernode)
+        if (rendernode) {
             vah_add_file(&buf, rendernode, "rw");
-        else
+        } else {
             if (virDomainGraphicsNeedsAutoRenderNode(graphics)) {
-                char * defaultRenderNode = virHostGetDRMRenderNode();
+                char *defaultRenderNode = virHostGetDRMRenderNode();
+
                 if (defaultRenderNode) {
                     vah_add_file(&buf, defaultRenderNode, "rw");
                     VIR_FREE(defaultRenderNode);
+                }
             }
         }

Reviewed-by: Erik Skultety <eskultet at redhat.com>