Commit 11e0a7c8 authored Jul 05, 2023 by Hans de Goede Committed by Mauro Carvalho Chehab Aug 10, 2023

media: ipu-bridge: Do not use on stack memory for software_node.name field



Commit 567f97bd ("media: ipu3-cio2: support multiple sensors and VCMs
with same HID") introduced an on stack vcm_name and then uses this for
the name field of the software_node struct used for the vcm.

But the software_node struct is much longer lived then the current
stack-frame, so this is no good.

Instead extend the ipu_node_names struct with an extra field to store
the vcm software_node name and use that.

Note this also changes the length of the allocated buffer from
ACPI_ID_LEN + 4 to 16. the name is filled with "<ipu_vcm_types[x]>-%u"
where ipu_vcm_types[x] is not an ACPI_ID. The maximum length of
the strings in the ipu_vcm_types[] array is 11 + 5 bytes for "-255\0"
means 16 bytes are needed in the worst case scenario.

Fixes: 567f97bd ("media: ipu3-cio2: support multiple sensors and VCMs with same HID")
Cc: Bingbu Cao <bingbu.cao@intel.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

parent 284be569

drivers/media/pci/intel/ipu-bridge.c

+3 −4

Original line number	Diff line number	Diff line
		@@ -220,7 +220,6 @@ static void ipu_bridge_create_connection_swnodes(struct ipu_bridge *bridge,
		struct ipu_sensor *sensor)
		{
		struct software_node *nodes = sensor->swnodes;
		char vcm_name[ACPI_ID_LEN + 4];

		ipu_bridge_init_swnode_names(sensor);

		@@ -240,10 +239,10 @@ static void ipu_bridge_create_connection_swnodes(struct ipu_bridge *bridge,
		sensor->ipu_properties);
		if (sensor->ssdb.vcmtype) {
		/* append ssdb.link to distinguish VCM nodes with same HID */
		snprintf(vcm_name, sizeof(vcm_name), "%s-%u",
		ipu_vcm_types[sensor->ssdb.vcmtype - 1],
		snprintf(sensor->node_names.vcm, sizeof(sensor->node_names.vcm),
		"%s-%u", ipu_vcm_types[sensor->ssdb.vcmtype - 1],
		sensor->ssdb.link);
		nodes[SWNODE_VCM] = NODE_VCM(vcm_name);
		nodes[SWNODE_VCM] = NODE_VCM(sensor->node_names.vcm);
		}

		ipu_bridge_init_swnode_group(sensor);

drivers/media/pci/intel/ipu-bridge.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -103,6 +103,7 @@ struct ipu_node_names {
		char port[7];
		char endpoint[11];
		char remote_port[7];
		char vcm[16];
		};

		struct ipu_sensor_config {