blob: d308a5ca699cf7346175096c0cc65a9c6b9bc4c4 [file] [log] [blame]
From: Peter Wu <peter@lekensteyn.nl>
Date: Mon, 11 Jul 2016 19:51:06 +0200
Subject: ALSA: hda - fix use-after-free after module unload
commit ab58d8cc870ef3f0771c197700441936898d1f1d upstream.
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: 246efa4a072f ("snd/hda: add runtime suspend/resume on optimus support (v4)")
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
sound/pci/hda/hda_intel.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -950,8 +950,10 @@ static int azx_free(struct azx *chip)
if (use_vga_switcheroo(chip)) {
if (chip->disabled && chip->bus)
snd_hda_unlock_devices(chip->bus);
- if (chip->vga_switcheroo_registered)
+ if (chip->vga_switcheroo_registered) {
vga_switcheroo_unregister_client(chip->pci);
+ vga_switcheroo_fini_domain_pm_ops(chip->card->dev);
+ }
}
if (chip->initialized) {