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From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Kangjie Lu <kjlu@umn.edu>, Daniel Vetter <daniel.vetter@ffwll.ch>,
        Sasha Levin <sashal@kernel.org>,
        dri-devel@lists.freedesktop.org
Subject: [PATCH AUTOSEL 5.4 018/330] gma/gma500: fix a memory disclosure bug due to uninitialized bytes
Date:   Thu, 17 Sep 2020 21:55:58 -0400
Message-Id: <20200918020110.2063155-18-sashal@kernel.org>
In-Reply-To: <20200918020110.2063155-1-sashal@kernel.org>
References: <20200918020110.2063155-1-sashal@kernel.org>
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From: Kangjie Lu <kjlu@umn.edu>

[ 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@umn.edu>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191018042953.31099-1-kjlu@umn.edu
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 f56852a503e8d..8b784947ed3b9 100644
--- a/drivers/gpu/drm/gma500/cdv_intel_display.c
+++ b/drivers/gpu/drm/gma500/cdv_intel_display.c
@@ -405,6 +405,8 @@ 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