mmc: dw_mmc-k3: Fix out-of-bounds access through DT alias

commit 325501d9360eb42c7c51e6daa0d733844c1e790b upstream.

The hs_timing_cfg[] array is indexed using a value derived from the
"mshcN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Fixes: 361c7fe9b02eee7e ("mmc: dw_mmc-k3: add sd support for hi3660")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mmc/host/dw_mmc-k3.c b/drivers/mmc/host/dw_mmc-k3.c
index 64cda84..665afd8 100644 (file)
--- a/drivers/mmc/host/dw_mmc-k3.c
+++ b/drivers/mmc/host/dw_mmc-k3.c
@@ -135,6 +135,9 @@ static int dw_mci_hi6220_parse_dt(struct dw_mci *host)
        if (priv->ctrl_id < 0)
                priv->ctrl_id = 0;
 
+       if (priv->ctrl_id >= TIMING_MODE)
+               return -EINVAL;
+
        host->priv = priv;
        return 0;
 }