6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Takashi Iwai <tiwai@xxxxxxx>
[ Upstream commit a0810c3d6dd2d29a9b92604d682eacd2902ce947 ]
The current 6fire code tries to release the resources right after the
call of usb6fire_chip_abort(). But at this moment, the card object
might be still in use (as we're calling snd_card_free_when_closed()).
For avoid potential UAFs, move the release of resources to the card's
private_free instead of the manual call of usb6fire_chip_destroy() at
the USB disconnect callback.
Fixes: c6d43ba816d1 ("ALSA: usb/6fire - Driver for TerraTec DMX 6Fire USB")
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Link: https://patch.msgid.link/20241113111042.15058-6-tiwai@xxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/usb/6fire/chip.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/sound/usb/6fire/chip.c b/sound/usb/6fire/chip.c
index 33e962178c936..d562a30b087f0 100644
--- a/sound/usb/6fire/chip.c
+++ b/sound/usb/6fire/chip.c
@@ -61,8 +61,10 @@ static void usb6fire_chip_abort(struct sfire_chip *chip)
}
}
-static void usb6fire_chip_destroy(struct sfire_chip *chip)
+static void usb6fire_card_free(struct snd_card *card)
{
+ struct sfire_chip *chip = card->private_data;
+
if (chip) {
if (chip->pcm)
usb6fire_pcm_destroy(chip);
@@ -72,8 +74,6 @@ static void usb6fire_chip_destroy(struct sfire_chip *chip)
usb6fire_comm_destroy(chip);
if (chip->control)
usb6fire_control_destroy(chip);
- if (chip->card)
- snd_card_free(chip->card);
}
}
@@ -136,6 +136,7 @@ static int usb6fire_chip_probe(struct usb_interface *intf,
chip->regidx = regidx;
chip->intf_count = 1;
chip->card = card;
+ card->private_free = usb6fire_card_free;
ret = usb6fire_comm_init(chip);
if (ret < 0)
@@ -162,7 +163,7 @@ static int usb6fire_chip_probe(struct usb_interface *intf,
return 0;
destroy_chip:
- usb6fire_chip_destroy(chip);
+ snd_card_free(card);
return ret;
}
@@ -181,7 +182,6 @@ static void usb6fire_chip_disconnect(struct usb_interface *intf)
chip->shutdown = true;
usb6fire_chip_abort(chip);
- usb6fire_chip_destroy(chip);
}
}
}
--
2.43.0
