linux-kernel - [PATCH DNI 24/26] media: pisp_be: Implement link validation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250717-multicontext-mainline-2025-v1-24-81ac18979c03@ideasonboard.com>
Date: Thu, 17 Jul 2025 12:45:50 +0200
From: Jacopo Mondi <jacopo.mondi@...asonboard.com>
To: Sakari Ailus <sakari.ailus@...ux.intel.com>, 
 Laurent Pinchart <laurent.pinchart@...asonboard.com>, 
 Tomi Valkeinen <tomi.valkeinen@...asonboard.com>, 
 Kieran Bingham <kieran.bingham@...asonboard.com>, 
 Nicolas Dufresne <nicolas.dufresne@...labora.com>, 
 Mauro Carvalho Chehab <mchehab@...nel.org>, 
 Tomasz Figa <tfiga@...omium.org>, 
 Marek Szyprowski <m.szyprowski@...sung.com>, 
 Raspberry Pi Kernel Maintenance <kernel-list@...pberrypi.com>, 
 Florian Fainelli <florian.fainelli@...adcom.com>, 
 Broadcom internal kernel review list <bcm-kernel-feedback-list@...adcom.com>, 
 Hans Verkuil <hverkuil@...nel.org>
Cc: linux-kernel@...r.kernel.org, linux-media@...r.kernel.org, 
 linux-rpi-kernel@...ts.infradead.org, linux-arm-kernel@...ts.infradead.org, 
 Jacopo Mondi <jacopo.mondi@...asonboard.com>
Subject: [PATCH DNI 24/26] media: pisp_be: Implement link validation

Implement link validation to validate that the sizes of the format on
the video device matches the size programmed on the ISP subdevice
connected pad.

Signed-off-by: Jacopo Mondi <jacopo.mondi@...asonboard.com>
---
 .../media/platform/raspberrypi/pisp_be/pisp_be.c   | 67 ++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c b/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c
index 22e440f387b5e5560b2cc80a8b3bf6064dc12d7c..2a8c09a9c70952c9f99e542271e994d62392c617 100644
--- a/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c
+++ b/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c
@@ -1362,6 +1362,67 @@ static const struct v4l2_ioctl_ops pispbe_node_ioctl_ops = {
 	.vidioc_streamoff = vb2_ioctl_streamoff,
 };
 
+static int pispbe_link_validate(struct media_link *link)
+{
+	const struct v4l2_mbus_framefmt *sd_fmt;
+	struct v4l2_pix_format_mplane *pix_mp;
+	struct v4l2_subdev_state *state;
+	struct media_entity *vdev_ent;
+	struct media_entity *sd_ent;
+	struct pispbe_node *node;
+	struct v4l2_subdev *sd;
+
+	if (is_media_entity_v4l2_video_device(link->source->entity)) {
+		vdev_ent = link->source->entity;
+		sd_ent = link->sink->entity;
+	} else {
+		sd_ent = link->source->entity;
+		vdev_ent = link->sink->entity;
+	}
+
+	node = container_of(media_entity_to_video_device(vdev_ent),
+			    struct pispbe_node, vfd);
+	switch (node->id) {
+	case TDN_INPUT_NODE:
+		fallthrough;
+	case STITCH_INPUT_NODE:
+		fallthrough;
+	case TDN_OUTPUT_NODE:
+		fallthrough;
+	case STITCH_OUTPUT_NODE:
+		fallthrough;
+	case CONFIG_NODE:
+		/* Skip validation for these nodes. */
+		return 0;
+	}
+	pix_mp = &node->format.fmt.pix_mp;
+
+	sd = media_entity_to_v4l2_subdev(sd_ent);
+	state = v4l2_subdev_get_unlocked_active_state(sd);
+	sd_fmt = v4l2_subdev_state_get_format(state, node->id);
+
+	/* Only check for sizes. */
+	if (pix_mp->width != sd_fmt->width) {
+		dev_dbg(node->pispbe->dev,
+			"%s: width does not match (vdev %u, sd %u)\n",
+			__func__, pix_mp->width, sd_fmt->width);
+		return -EPIPE;
+	}
+
+	if (pix_mp->height != sd_fmt->height) {
+		dev_dbg(node->pispbe->dev,
+			"%s: height does not match (vdev %u, sd %u)\n",
+			__func__, pix_mp->height, sd_fmt->height);
+		return -EPIPE;
+	}
+
+	return 0;
+}
+
+static const struct media_entity_operations pispbe_node_entity_ops = {
+	.link_validate = pispbe_link_validate,
+};
+
 static const struct video_device pispbe_videodev = {
 	.name = PISPBE_NAME,
 	.vfl_dir = VFL_DIR_M2M, /* gets overwritten */
@@ -1445,6 +1506,7 @@ static int pispbe_init_node(struct pispbe_dev *pispbe, unsigned int id)
 	vdev->device_caps = V4L2_CAP_STREAMING | node_desc[id].caps;
 
 	node->pad.flags = output ? MEDIA_PAD_FL_SOURCE : MEDIA_PAD_FL_SINK;
+	entity->ops = &pispbe_node_entity_ops;
 	ret = media_entity_pads_init(entity, 1, &node->pad);
 	if (ret) {
 		dev_err(pispbe->dev,
@@ -1561,6 +1623,10 @@ static const struct v4l2_subdev_internal_ops pispbe_subdev_internal_ops = {
 	.init_state = pispbe_init_state,
 };
 
+static const struct media_entity_operations pispbe_subdev_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+
 static int pispbe_init_subdev(struct pispbe_dev *pispbe)
 {
 	struct v4l2_subdev *sd = &pispbe->sd;
@@ -1569,6 +1635,7 @@ static int pispbe_init_subdev(struct pispbe_dev *pispbe)
 	v4l2_subdev_init(sd, &pispbe_sd_ops);
 	sd->internal_ops = &pispbe_subdev_internal_ops;
 	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
+	sd->entity.ops = &pispbe_subdev_entity_ops;
 	sd->owner = THIS_MODULE;
 	sd->dev = pispbe->dev;
 	strscpy(sd->name, PISPBE_NAME, sizeof(sd->name));

-- 
2.49.0