drm/bridge: it66121: Initialize {device,vendor}_ids

BugLink: https://bugs.launchpad.net/bugs/1951822
[ Upstream commit 3a5f3d61de657bc1c2b53b77d065c5526f982e10 ]

These two arrays are populated with data read from the I2C device
through regmap_read(), and the data is then compared with hardcoded
vendor/product ID values of supported chips.

However, the return value of regmap_read() was never checked. This is
fine, as long as the two arrays are zero-initialized, so that we don't
compare the vendor/product IDs against whatever garbage is left on the
stack.

Address this issue by zero-initializing these two arrays.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Fixes: 988156dc2fc9 ("drm: bridge: add it66121 driver")
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210827163956.27517-1-paul@crapouillou.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c
index 2f2a09adb4bc83c237e5b74703978e27c3e206ba..b130d01147c6c3cbafbf5690bbf691028880e618 100644 (file)
--- a/drivers/gpu/drm/bridge/ite-it66121.c
+++ b/drivers/gpu/drm/bridge/ite-it66121.c
@@ -889,7 +889,7 @@ unlock:
 static int it66121_probe(struct i2c_client *client,
                         const struct i2c_device_id *id)
 {
-       u32 vendor_ids[2], device_ids[2], revision_id;
+       u32 revision_id, vendor_ids[2] = { 0 }, device_ids[2] = { 0 };
        struct device_node *ep;
        int ret;
        struct it66121_ctx *ctx;