ALSA: hda - fix use-after-free after module unload

register_vga_switcheroo() sets the PM ops from the hda structure which
is freed later in azx_free. Make sure that these ops are cleared.

Caught by KASAN, initially noticed due to a general protection fault.

Fixes: 246efa4a07 ("snd/hda: add runtime suspend/resume on optimus support (v4)")
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Peter Wu 2016-07-11 19:51:06 +02:00 committed by Takashi Iwai
parent a8ff48cb70
commit ab58d8cc87

View file

@ -1218,8 +1218,10 @@ static int azx_free(struct azx *chip)
if (use_vga_switcheroo(hda)) { if (use_vga_switcheroo(hda)) {
if (chip->disabled && hda->probe_continued) if (chip->disabled && hda->probe_continued)
snd_hda_unlock_devices(&chip->bus); snd_hda_unlock_devices(&chip->bus);
if (hda->vga_switcheroo_registered) if (hda->vga_switcheroo_registered) {
vga_switcheroo_unregister_client(chip->pci); vga_switcheroo_unregister_client(chip->pci);
vga_switcheroo_fini_domain_pm_ops(chip->card->dev);
}
} }
if (bus->chip_init) { if (bus->chip_init) {