drm/i915/dsi: defend gpio table against out of bounds access

Do not blindly trust the VBT data used for indexing.

Cc: stable@vger.kernel.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/cc32d40c2b47f2d2151811855ac2c3dabab1d57d.1454582914.git.jani.nikula@intel.com
(cherry picked from commit 5d2d0a12d3)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This commit is contained in:
Jani Nikula 2016-02-04 12:50:49 +02:00
parent 949d0b51be
commit 4db3a2448e

View file

@ -209,6 +209,11 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
/* pull up/down */
action = *data++;
if (gpio >= ARRAY_SIZE(gtable)) {
DRM_DEBUG_KMS("unknown gpio %u\n", gpio);
goto out;
}
function = gtable[gpio].function_reg;
pad = gtable[gpio].pad_reg;
@ -226,6 +231,7 @@ static const u8 *mipi_exec_gpio(struct intel_dsi *intel_dsi, const u8 *data)
vlv_gpio_nc_write(dev_priv, pad, val);
mutex_unlock(&dev_priv->sb_lock);
out:
return data;
}