Commit ab58d8cc authored Jul 11, 2016 by Peter Wu Committed by Takashi Iwai Jul 11, 2016

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: 246efa4a ("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>

parent a8ff48cb

sound/pci/hda/hda_intel.c

+3 −1

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

		if (bus->chip_init) {