From 549f8ffc7b2f7561bea7f90930b6c5104318e87b Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 26 Jan 2022 15:50:11 +0100 Subject: ALSA: hda: Fix UAF of leds class devs at unbinding The LED class devices that are created by HD-audio codec drivers are registered via devm_led_classdev_register() and associated with the HD-audio codec device. Unfortunately, it turned out that the devres release doesn't work for this case; namely, since the codec resource release happens before the devm call chain, it triggers a NULL dereference or a UAF for a stale set_brightness_delay callback. For fixing the bug, this patch changes the LED class device register and unregister in a manual manner without devres, keeping the instances in hda_gen_spec. Reported-by: Alexander Sergeyev Cc: Link: https://lore.kernel.org/r/20220111195229.a77wrpjclqwrx4bx@localhost.localdomain Link: https://lore.kernel.org/r/20220126145011.16728-1-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/pci/hda/hda_generic.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'sound/pci/hda/hda_generic.h') diff --git a/sound/pci/hda/hda_generic.h b/sound/pci/hda/hda_generic.h index 8e1bc8ea74fc..34eba40cc6e6 100644 --- a/sound/pci/hda/hda_generic.h +++ b/sound/pci/hda/hda_generic.h @@ -294,6 +294,9 @@ struct hda_gen_spec { struct hda_jack_callback *cb); void (*mic_autoswitch_hook)(struct hda_codec *codec, struct hda_jack_callback *cb); + + /* leds */ + struct led_classdev *led_cdevs[NUM_AUDIO_LEDS]; }; /* values for add_stereo_mix_input flag */ -- cgit