[PATCH 4.4 72/73] qxl: check for kmap failures

Greg Kroah-Hartman
2016-09-28T09:10:45Z

From: Dan Carpenter <dan.carpenter@oracle.com>

commit f4cceb2affcd1285d4ce498089e8a79f4cd2fa66 upstream.

If kmap fails, it leads to memory corruption.

Fixes: f64122c1f6ad ('drm: add new QXL driver. (v1.4)')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160711084633.GA31411@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/qxl/qxl_draw.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/gpu/drm/qxl/qxl_draw.c
+++ b/drivers/gpu/drm/qxl/qxl_draw.c
@@ -136,6 +136,8 @@ static int qxl_palette_create_1bit(struc
* correctly globaly, since that would require
* tracking all of our palettes. */
ret = qxl_bo_kmap(palette_bo, (void **)&pal);
+ if (ret)
+ return ret;
pal->num_ents = 2;
pal->unique = unique++;
if (visual == FB_VISUAL_TRUECOLOR || visual == FB_VISUAL_DIRECTCOLOR) {