[PATCH 4.4 14/85] gma/gma500: fix a memory disclosure bug due to uninitialized bytes

[Greg Kroah-Hartman]

From: Kangjie Lu <kjlu@xxxxxxx>

[ Upstream commit 57a25a5f754ce27da2cfa6f413cfd366f878db76 ]

`best_clock` is an object that may be sent out. Object `clock`
contains uninitialized bytes that are copied to `best_clock`,
which leads to memory disclosure and information leak.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20191018042953.31099-1-kjlu@xxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/gma500/cdv_intel_display.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/gma500/cdv_intel_display.c b/drivers/gpu/drm/gma500/cdv_intel_display.c
index 7d47b3d5cc0d0..54d554d720004 100644
--- a/drivers/gpu/drm/gma500/cdv_intel_display.c
+++ b/drivers/gpu/drm/gma500/cdv_intel_display.c
@@ -415,6 +415,8 @@ static bool cdv_intel_find_dp_pll(const struct gma_limit_t *limit,
 	struct gma_crtc *gma_crtc = to_gma_crtc(crtc);
 	struct gma_clock_t clock;
 
+	memset(&clock, 0, sizeof(clock));
+
 	switch (refclk) {
 	case 27000:
 		if (target < 200000) {
-- 
2.25.1