On Mon Mar 16 13:34:46 2026 +0000, Ricardo Ribalda wrote:
> Some camera modules have XU controls that can configure the behaviour of
> the privacy LED.
>
> Block mapping of those controls, unless the module is configured with
> a new parameter: allow_privacy_override.
>
> Signed-off-by: Ricardo Ribalda <[email protected]>
> [[email protected]: Remove deprecation warning from param]
> Reviewed-by: Hans de Goede <[email protected]>
> Signed-off-by: Hans de Goede <[email protected]>
> Signed-off-by: Hans Verkuil <[email protected]>
Patch committed.
Thanks,
Hans Verkuil
drivers/media/usb/uvc/uvc_ctrl.c | 38 ++++++++++++++++++++++++++++++++++++++
drivers/media/usb/uvc/uvc_driver.c | 4 ++++
drivers/media/usb/uvc/uvc_v4l2.c | 7 +++++++
drivers/media/usb/uvc/uvcvideo.h | 2 ++
include/linux/usb/uvc.h | 4 ++++
5 files changed, 55 insertions(+)
---
diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index b6e020b41671..3ca108b83f1d 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -3001,6 +3001,35 @@ static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
return ret;
}
+bool uvc_ctrl_is_privacy_control(u8 entity[16], u8 selector)
+{
+ /*
+ * This list is not exhaustive, it is a best effort to block access to
+ * non documented controls that can affect user's privacy.
+ */
+ struct privacy_control {
+ u8 entity[16];
+ u8 selector;
+ } privacy_control[] = {
+ {
+ .entity = UVC_GUID_LOGITECH_USER_HW_CONTROL_V1,
+ .selector = 1,
+ },
+ {
+ .entity = UVC_GUID_LOGITECH_PERIPHERAL,
+ .selector = 9,
+ },
+ };
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(privacy_control); i++)
+ if (!memcmp(entity, privacy_control[i].entity, 16) &&
+ selector == privacy_control[i].selector)
+ return true;
+
+ return false;
+}
+
int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
struct uvc_xu_control_query *xqry)
{
@@ -3045,6 +3074,15 @@ int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
return -ENOENT;
}
+ if (uvc_ctrl_is_privacy_control(entity->guid, xqry->selector) &&
+ !uvc_allow_privacy_override_param) {
+ dev_warn_once(&chain->dev->intf->dev,
+ "Privacy related controls can only be accessed if
module parameter allow_privacy_override is true\n");
+ uvc_dbg(chain->dev, CONTROL, "Blocking access to privacy
related Control %pUl/%u\n",
+ entity->guid, xqry->selector);
+ return -EACCES;
+ }
+
if (mutex_lock_interruptible(&chain->ctrl_mutex))
return -ERESTARTSYS;
diff --git a/drivers/media/usb/uvc/uvc_driver.c
b/drivers/media/usb/uvc/uvc_driver.c
index 31b4ac3b48c1..e289cc71ba98 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -36,6 +36,7 @@ unsigned int uvc_no_drop_param = 1;
static unsigned int uvc_quirks_param = -1;
unsigned int uvc_dbg_param;
unsigned int uvc_timeout_param = UVC_CTRL_STREAMING_TIMEOUT;
+bool uvc_allow_privacy_override_param;
static struct usb_driver uvc_driver;
@@ -2504,6 +2505,9 @@ module_param_named(trace, uvc_dbg_param, uint, 0644);
MODULE_PARM_DESC(trace, "Trace level bitmask");
module_param_named(timeout, uvc_timeout_param, uint, 0644);
MODULE_PARM_DESC(timeout, "Streaming control requests timeout");
+module_param_named(allow_privacy_override, uvc_allow_privacy_override_param,
bool, 0644);
+MODULE_PARM_DESC(allow_privacy_override,
+ "Allow access to privacy related controls");
/* ------------------------------------------------------------------------
* Driver initialization and cleanup
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index fa852b789193..644c2f1cd8e6 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -133,6 +133,13 @@ static int uvc_ioctl_xu_ctrl_map(struct uvc_video_chain
*chain,
return -EINVAL;
}
+ if (uvc_ctrl_is_privacy_control(xmap->entity, xmap->selector) &&
+ !uvc_allow_privacy_override_param) {
+ dev_warn_once(&chain->dev->intf->dev,
+ "Privacy related controls can only be mapped if
module parameter allow_privacy_override is true\n");
+ return -EACCES;
+ }
+
map = kzalloc_obj(*map);
if (map == NULL)
return -ENOMEM;
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 0a0c01b2420f..4ba35727e954 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -666,6 +666,7 @@ extern unsigned int uvc_no_drop_param;
extern unsigned int uvc_dbg_param;
extern unsigned int uvc_timeout_param;
extern unsigned int uvc_hw_timestamps_param;
+extern bool uvc_allow_privacy_override_param;
#define uvc_dbg(_dev, flag, fmt, ...) \
do { \
@@ -791,6 +792,7 @@ int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
struct uvc_xu_control_query *xqry);
void uvc_ctrl_cleanup_fh(struct uvc_fh *handle);
+bool uvc_ctrl_is_privacy_control(u8 entity[16], u8 selector);
/* Utility functions */
struct usb_host_endpoint *uvc_find_endpoint(struct usb_host_interface *alts,
diff --git a/include/linux/usb/uvc.h b/include/linux/usb/uvc.h
index 84f35c6f4d6e..99b070ab860f 100644
--- a/include/linux/usb/uvc.h
+++ b/include/linux/usb/uvc.h
@@ -49,6 +49,10 @@
#define UVC_GUID_LOGITECH_PERIPHERAL \
{0x21, 0x2d, 0xe5, 0xff, 0x30, 0x80, 0x2c, 0x4e, \
0x82, 0xd9, 0xf5, 0x87, 0xd0, 0x05, 0x40, 0xbd }
+#define UVC_GUID_LOGITECH_USER_HW_CONTROL_V1 \
+ {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
+ 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1f }
+
/*
https://learn.microsoft.com/en-us/windows-hardware/drivers/stream/uvc-extensions-1-5#222-extension-unit-controls
*/
#define UVC_MSXU_CONTROL_FOCUS 0x01
_______________________________________________
linuxtv-commits mailing list -- [email protected]
To unsubscribe send an email to [email protected]
