Commit 830988b6 authored by Haoxiang Li's avatar Haoxiang Li Committed by Takashi Iwai
Browse files

ALSA: ac97: fix a double free in snd_ac97_controller_register() 



If ac97_add_adapter() fails, put_device() is the correct way to drop
the device reference. kfree() is not required.
Add kfree() if idr_alloc() fails and in ac97_adapter_release() to do
the cleanup.

Found by code review.

Fixes: 74426fbf ("ALSA: ac97: add an ac97 bus")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarHaoxiang Li <lihaoxiang@isrc.iscas.ac.cn>
Link: https://patch.msgid.link/20251219162845.657525-1-lihaoxiang@isrc.iscas.ac.cn


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 17753d17

sound/ac97/bus.c

+5 −5
Original line number Diff line number Diff line
@@ -298,6 +298,7 @@ static void ac97_adapter_release(struct device *dev) 
	idr_remove(&ac97_adapter_idr, ac97_ctrl->nr);

	dev_dbg(&ac97_ctrl->adap, "adapter unregistered by %s\n",

		dev_name(ac97_ctrl->parent));

	kfree(ac97_ctrl);

}



static const struct device_type ac97_adapter_type = {
@@ -319,7 +320,9 @@ static int ac97_add_adapter(struct ac97_controller *ac97_ctrl) 
		ret = device_register(&ac97_ctrl->adap);

		if (ret)

			put_device(&ac97_ctrl->adap);

	}

	} else

		kfree(ac97_ctrl);



	if (!ret) {

		list_add(&ac97_ctrl->controllers, &ac97_controllers);

		dev_dbg(&ac97_ctrl->adap, "adapter registered by %s\n",
@@ -361,14 +364,11 @@ struct ac97_controller *snd_ac97_controller_register( 
	ret = ac97_add_adapter(ac97_ctrl);



	if (ret)

		goto err;

		return ERR_PTR(ret);

	ac97_bus_reset(ac97_ctrl);

	ac97_bus_scan(ac97_ctrl);



	return ac97_ctrl;

err:

	kfree(ac97_ctrl);

	return ERR_PTR(ret);

}

EXPORT_SYMBOL_GPL(snd_ac97_controller_register);