From ec8d771cc9f7573a50aecf61ca77241617e810fc Mon Sep 17 00:00:00 2001
From: Emil Velikov <emil.velikov@collabora.com>
Date: Fri, 1 Nov 2019 13:03:10 +0000
Subject: drm/vmwgfx: check master authentication in surface_ref ioctls
Git-commit: 4872e6aa217fbb475ffa0ad7bda0d9acff543f2c
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
With later commit we'll rework DRM authentication handling. Namely
DRM_AUTH will not be a requirement for DRM_RENDER_ALLOW ioctls.
Since vmwgfx does isolation for primary clients in different master
realms, the DRM_AUTH can be dropped.
The only place where authentication matters, is surface_reference ioctls
whenever a legacy (non-prime) handle is used. For those ioctls we call
vmw_surface_handle_reference(), where we explicitly check if the client
is both a) master and b) unauthenticated - bailing out as result.
Otherwise the usual isolation path kicks in and we're all good.
v2: Reword commit message, since the isolation work has landed.
Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
index 590bde993946..3ce630aa4fde 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -961,6 +961,13 @@ vmw_surface_handle_reference(struct vmw_private *dev_priv,
user_srf = container_of(base, struct vmw_user_surface,
prime.base);
+ /* Error out if we are unauthenticated primary */
+ if (drm_is_primary_client(file_priv) &&
+ !file_priv->authenticated) {
+ ret = -EACCES;
+ goto out_bad_resource;
+ }
+
/*
* Make sure the surface creator has the same
* authenticating master, or is already registered with us.
--
2.28.0