[Intel-gfx] [PATCH] drm/i915/bios: fix off by one in parse_generic_dtd()

[Jani Nikula]

On Thu, 12 Dec 2019, Matt Roper <matthew.d.roper at intel.com> wrote:
> On Thu, Dec 12, 2019 at 12:11:30PM +0300, Dan Carpenter wrote:
>> The "num_dtd" variable is the number of elements in the
>> generic_dtd->dtd[] array so the > needs to be >= to prevent reading one
>> element beyond the end of the array.
>> 
>> Fixes: 33ef6d4fd8df ("drm/i915/vbt: Handle generic DTD block")
>> Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
>
> Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

Pushed to drm-intel-next-queued, thanks for the patch and review.

BR,
Jani.

>
>> ---
>>  drivers/gpu/drm/i915/display/intel_bios.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
>> index 1aeecdd02293..d1e27ee86e53 100644
>> --- a/drivers/gpu/drm/i915/display/intel_bios.c
>> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
>> @@ -338,7 +338,7 @@ parse_generic_dtd(struct drm_i915_private *dev_priv,
>>  
>>  	num_dtd = (get_blocksize(generic_dtd) -
>>  		   sizeof(struct bdb_generic_dtd)) / generic_dtd->gdtd_size;
>> -	if (dev_priv->vbt.panel_type > num_dtd) {
>> +	if (dev_priv->vbt.panel_type >= num_dtd) {
>>  		DRM_ERROR("Panel type %d not found in table of %d DTD's\n",
>>  			  dev_priv->vbt.panel_type, num_dtd);
>>  		return;
>> -- 
>> 2.11.0
>> 

-- 
Jani Nikula, Intel Open Source Graphics Center