[PATCH 4.20 42/50] drm/vmwgfx: Fix an uninitialized fence handle value

From: Greg Kroah-Hartman
Date: Wed Feb 13 2019 - 13:46:33 EST


4.20-stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Hellstrom <thellstrom@xxxxxxxxxx>

commit 51fdbeb4ca1a8415c98f87cb877956ae83e71627 upstream.

if vmw_execbuf_fence_commands() fails, The handle value will be
uninitialized and a bogus fence handle might be copied to user-space.

Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: 2724b2d54cda: ("drm/vmwgfx: Use new validation interface for the modesetting code v2")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
Reviewed-by: Brian Paul <brianp@xxxxxxxxxx> #v1
Reviewed-by: Sinclair Yeh <syeh@xxxxxxxxxx> #v1
Reviewed-by: Deepak Rawat <drawat@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -2592,8 +2592,8 @@ void vmw_kms_helper_validation_finish(st
user_fence_rep)
{
struct vmw_fence_obj *fence = NULL;
- uint32_t handle;
- int ret;
+ uint32_t handle = 0;
+ int ret = 0;

if (file_priv || user_fence_rep || vmw_validation_has_bos(ctx) ||
out_fence)