diff options
| author | David Herrmann <dh.herrmann@gmail.com> | 2014-07-22 19:12:26 +0400 |
|---|---|---|
| committer | David Herrmann <dh.herrmann@gmail.com> | 2014-08-05 18:07:55 +0400 |
| commit | 3cb01a980461506f9ec4e4e1dc2dab6314236fb7 (patch) | |
| tree | e35eb24679bda6f69a1f216ba33522b603262dc7 /drivers/gpu/drm/drm_fops.c | |
| parent | 48ba813701eb14b3008edefef4a0789b328e278c (diff) | |
| download | linux-3cb01a980461506f9ec4e4e1dc2dab6314236fb7.tar.xz | |
drm: don't de-authenticate clients on master-close
If an active DRM-Master closes its device, we deauthenticate all clients
on that master. However, if an inactive DRM-Master closes its device, we
do nothing. This is quite inconsistent and breaks several scenarios:
1) If this was used as security mechanism, it fails horribly if a master
closes a device while VT switched away. Furthermore, none of the few
drivers using ->master_*() callbacks seems to require it, anyway.
2) If you spawn weston (or any other non-UMS compositor) in background
while another compositor is active, both will get assigned to the
same "drm_master" object. If the foreground compositor now exits, all
clients of both the foreground AND background compositor will be
de-authenticated leading to unexpected behavior.
Stop this non-sense and keep clients authenticated. We don't do this when
dropping DRM-Master (i.e., switching VTs) so don't do it on active-close
either!
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Diffstat (limited to 'drivers/gpu/drm/drm_fops.c')
| -rw-r--r-- | drivers/gpu/drm/drm_fops.c | 13 |
1 files changed, 2 insertions, 11 deletions
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 53435e07fa8d..3299175da6ac 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -199,8 +199,7 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor) priv->minor = minor; /* for compatibility root is always authenticated */ - priv->always_authenticated = capable(CAP_SYS_ADMIN); - priv->authenticated = priv->always_authenticated; + priv->authenticated = capable(CAP_SYS_ADMIN); priv->lock_count = 0; INIT_LIST_HEAD(&priv->lhead); @@ -462,20 +461,12 @@ int drm_release(struct inode *inode, struct file *filp) if (drm_is_master(file_priv)) { struct drm_master *master = file_priv->master; - struct drm_file *temp; - - mutex_lock(&dev->struct_mutex); - list_for_each_entry(temp, &dev->filelist, lhead) { - if ((temp->master == file_priv->master) && - (temp != file_priv)) - temp->authenticated = temp->always_authenticated; - } /** * Since the master is disappearing, so is the * possibility to lock. */ - + mutex_lock(&dev->struct_mutex); if (master->lock.hw_lock) { if (dev->sigdata.lock == master->lock.hw_lock) dev->sigdata.lock = NULL; |