1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
From a19afebb883f2a02ecf4b8d5a114ce6957a59238 Mon Sep 17 00:00:00 2001
From: Thomas Hellstrom <thellstrom@vmware.com>
Date: Wed, 26 Aug 2015 05:49:21 -0700
Subject: [PATCH 2/2] drm/vmwgfx: Allow dropped masters render-node like access
on legacy nodes v2
Applications like gnome-shell may try to render after dropping master
privileges. Since the driver should now be safe against this scenario,
allow those applications to use their legacy node like a render node.
v2: Add missing return statement.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
---
drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 7 ++++++-
drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 6 ++++++
2 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index a4766acd0ea2..d022b509f1ac 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -993,10 +993,15 @@ static struct vmw_master *vmw_master_check(struct drm_device *dev,
}
/*
- * Check if we were previously master, but now dropped.
+ * Check if we were previously master, but now dropped. In that
+ * case, allow at least render node functionality.
*/
if (vmw_fp->locked_master) {
mutex_unlock(&dev->master_mutex);
+
+ if (flags & DRM_RENDER_ALLOW)
+ return NULL;
+
DRM_ERROR("Dropped master trying to access ioctl that "
"requires authentication.\n");
return ERR_PTR(-EACCES);
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
index 4d0c98edeb6a..7fc3e8abd0c4 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -906,6 +906,12 @@ vmw_surface_handle_reference(struct vmw_private *dev_priv,
"surface reference.\n");
return -EACCES;
}
+ if (ACCESS_ONCE(vmw_fpriv(file_priv)->locked_master)) {
+ DRM_ERROR("Locked master refused legacy "
+ "surface reference.\n");
+ return -EACCES;
+ }
+
handle = u_handle;
}
--
2.4.3
|
