From: Ricardo Ribalda Date: Mon, 16 Mar 2026 13:34:46 +0000 (+0000) Subject: media: uvcvideo: Introduce allow_privacy_override module parameter X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=02f93b4f940c66b99258cce954dcaeda7b3295a8;p=thirdparty%2Fkernel%2Flinux.git media: uvcvideo: Introduce allow_privacy_override module parameter 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 [johannes.goede@oss.qualcomm.com: Remove deprecation warning from param] Reviewed-by: Hans de Goede Signed-off-by: Hans de Goede Signed-off-by: Hans Verkuil --- 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