From: Mirela Rabulea Date: Fri, 22 May 2026 14:31:20 +0000 (+0300) Subject: media: v4l2-fwnode: Fix subdev owner overwritten in v4l2_async_register_subdev_sensor() X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=06cb687a5132fcffe624c0070576ab852ac6b568;p=thirdparty%2Flinux.git media: v4l2-fwnode: Fix subdev owner overwritten in v4l2_async_register_subdev_sensor() The v4l2 helper v4l2_async_register_subdev_sensor() calls v4l2_async_register_subdev(), which is a macro that expands to __v4l2_async_register_subdev(sd,THIS_MODULE). Since the macro is expanded inside v4l2-fwnode.c, THIS_MODULE resolves to the v4l2-fwnode module rather than the sensor driver module that originally set sd->owner. When v4l2-fwnode is built-in, THIS_MODULE evaluates to NULL, which then overwrites the sensor driver's owner with NULL. This causes the problem that the sensor module's reference count is never incremented during async registration, so the module can be removed while the subdevice is still in use by a notifier (e.g., a CSI-2 receiver bridge driver). Fix this by renaming v4l2_async_register_subdev_sensor() to __v4l2_async_register_subdev_sensor() with an added explicit module argument and introducing a wrapper macro: #define v4l2_async_register_subdev_sensor(sd) \ __v4l2_async_register_subdev_sensor(sd, THIS_MODULE) This ensures the sensor driver module is properly referenced even when the sensor driver does not init the owner field before calling v4l2_async_register_subdev_sensor() and prevents premature module removal. Fixes: aef69d54755d ("media: v4l: fwnode: Add a convenience function for registering sensors") Cc: stable@vger.kernel.org Suggested-by: Frank Li Link: https://lore.kernel.org/linux-media/20240315073125.275501-2-sakari.ailus@linux.intel.com/ Signed-off-by: Mirela Rabulea Reviewed-by: Laurent Pinchart Reviewed-by: Frank Li Signed-off-by: Sakari Ailus --- diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c index 77f3298821b5..62a3a452f788 100644 --- a/drivers/media/v4l2-core/v4l2-fwnode.c +++ b/drivers/media/v4l2-core/v4l2-fwnode.c @@ -1256,7 +1256,7 @@ v4l2_async_nf_parse_fwnode_sensor(struct device *dev, return 0; } -int v4l2_async_register_subdev_sensor(struct v4l2_subdev *sd) +int __v4l2_async_register_subdev_sensor(struct v4l2_subdev *sd, struct module *module) { struct v4l2_async_notifier *notifier; int ret; @@ -1282,7 +1282,7 @@ int v4l2_async_register_subdev_sensor(struct v4l2_subdev *sd) if (ret < 0) goto out_cleanup; - ret = v4l2_async_register_subdev(sd); + ret = __v4l2_async_register_subdev(sd, module); if (ret < 0) goto out_unregister; @@ -1300,7 +1300,7 @@ out_cleanup: return ret; } -EXPORT_SYMBOL_GPL(v4l2_async_register_subdev_sensor); +EXPORT_SYMBOL_GPL(__v4l2_async_register_subdev_sensor); MODULE_DESCRIPTION("V4L2 fwnode binding parsing library"); MODULE_LICENSE("GPL"); diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h index f26c323e9c96..54a2d9620ed5 100644 --- a/include/media/v4l2-async.h +++ b/include/media/v4l2-async.h @@ -333,8 +333,10 @@ int __v4l2_async_register_subdev(struct v4l2_subdev *sd, struct module *module); * An error is returned if the module is no longer loaded on any attempts * to register it. */ +#define v4l2_async_register_subdev_sensor(sd) \ + __v4l2_async_register_subdev_sensor(sd, THIS_MODULE) int __must_check -v4l2_async_register_subdev_sensor(struct v4l2_subdev *sd); +__v4l2_async_register_subdev_sensor(struct v4l2_subdev *sd, struct module *module); /** * v4l2_async_unregister_subdev - unregisters a sub-device to the asynchronous