media: v4l2-fwnode: suppress a warning at OF parsing logic

smatch produce this warning:
	drivers/media/v4l2-core/v4l2-fwnode.c:76 v4l2_fwnode_endpoint_parse_csi_bus() error: buffer overflow 'array' 5 <= u16max

That's because, in thesis, the routine might have called with
some value at bus->num_data_lanes. That's not the current
case.

Yet, better to shut up this warning, and make the code more
reliable if some future changes might cause a bug.

While here, simplify the code a little bit by reading only
once from lanes-properties array.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Mauro Carvalho Chehab 2017-06-26 14:07:54 -04:00
parent 1ad371deb9
commit 4ee236219f
2 changed files with 18 additions and 20 deletions

View File

@ -48,10 +48,9 @@ static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
rval = fwnode_property_read_u32_array(fwnode, "data-lanes", NULL, 0);
if (rval > 0) {
u32 array[ARRAY_SIZE(bus->data_lanes)];
u32 array[MAX_DATA_LANES + 1];
bus->num_data_lanes =
min_t(int, ARRAY_SIZE(bus->data_lanes), rval);
bus->num_data_lanes = min_t(int, MAX_DATA_LANES, rval);
fwnode_property_read_u32_array(fwnode, "data-lanes", array,
bus->num_data_lanes);
@ -64,24 +63,21 @@ static int v4l2_fwnode_endpoint_parse_csi2_bus(struct fwnode_handle *fwnode,
bus->data_lanes[i] = array[i];
}
}
rval = fwnode_property_read_u32_array(fwnode, "lane-polarities", NULL,
0);
if (rval > 0) {
u32 array[ARRAY_SIZE(bus->lane_polarities)];
rval = fwnode_property_read_u32_array(fwnode,
"lane-polarities", array,
1 + bus->num_data_lanes);
if (rval > 0) {
if (rval != 1 + bus->num_data_lanes /* clock + data */) {
pr_warn("invalid number of lane-polarities entries (need %u, got %u)\n",
1 + bus->num_data_lanes, rval);
return -EINVAL;
}
if (rval < 1 + bus->num_data_lanes /* clock + data */) {
pr_warn("too few lane-polarities entries (need %u, got %u)\n",
1 + bus->num_data_lanes, rval);
return -EINVAL;
for (i = 0; i < 1 + bus->num_data_lanes; i++)
bus->lane_polarities[i] = array[i];
}
fwnode_property_read_u32_array(fwnode, "lane-polarities", array,
1 + bus->num_data_lanes);
for (i = 0; i < 1 + bus->num_data_lanes; i++)
bus->lane_polarities[i] = array[i];
}
if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) {

View File

@ -26,6 +26,8 @@
struct fwnode_handle;
#define MAX_DATA_LANES 4
/**
* struct v4l2_fwnode_bus_mipi_csi2 - MIPI CSI-2 bus data structure
* @flags: media bus (V4L2_MBUS_*) flags
@ -37,10 +39,10 @@ struct fwnode_handle;
*/
struct v4l2_fwnode_bus_mipi_csi2 {
unsigned int flags;
unsigned char data_lanes[4];
unsigned char data_lanes[MAX_DATA_LANES];
unsigned char clock_lane;
unsigned short num_data_lanes;
bool lane_polarities[5];
bool lane_polarities[MAX_DATA_LANES + 1];
};
/**