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

Greg Kroah-Hartman
2019-02-13T18:46:34Z

From: Thomas Hellstrom <thellstrom@vmware.com>

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

---
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)