[PATCH] drm/gma500: fix memory disclosures due to uninitialized bytes

From: Kangjie Lu
Date: Fri Oct 18 2019 - 01:00:26 EST


"clock" may be copied to "best_clock". Initializing best_clock
is not sufficient. The fix initializes clock as well to avoid
memory disclosures and informaiton leaks.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
---
drivers/gpu/drm/gma500/oaktrail_crtc.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/gma500/oaktrail_crtc.c b/drivers/gpu/drm/gma500/oaktrail_crtc.c
index 167c10767dd4..900e5499249d 100644
--- a/drivers/gpu/drm/gma500/oaktrail_crtc.c
+++ b/drivers/gpu/drm/gma500/oaktrail_crtc.c
@@ -129,6 +129,7 @@ static bool mrst_sdvo_find_best_pll(const struct gma_limit_t *limit,
s32 freq_error, min_error = 100000;

memset(best_clock, 0, sizeof(*best_clock));
+ memset(&clock, 0, sizeof(clock));

for (clock.m = limit->m.min; clock.m <= limit->m.max; clock.m++) {
for (clock.n = limit->n.min; clock.n <= limit->n.max;
@@ -185,6 +186,7 @@ static bool mrst_lvds_find_best_pll(const struct gma_limit_t *limit,
int err = target;

memset(best_clock, 0, sizeof(*best_clock));
+ memset(&clock, 0, sizeof(clock));

for (clock.m = limit->m.min; clock.m <= limit->m.max; clock.m++) {
for (clock.p1 = limit->p1.min; clock.p1 <= limit->p1.max;
--
2.17.1