5.4-stable review patch. If anyone has any objections, please let me know.
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From: Takashi Iwai tiwai@suse.de
[ 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@suse.de Link: https://patch.msgid.link/20241113111042.15058-6-tiwai@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- 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 08c6e6a52eb98..ad6f89845a5c2 100644 --- a/sound/usb/6fire/chip.c +++ b/sound/usb/6fire/chip.c @@ -62,8 +62,10 @@ 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); @@ -73,8 +75,6 @@ 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); } }
@@ -137,6 +137,7 @@ 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) @@ -163,7 +164,7 @@ static int usb6fire_chip_probe(struct usb_interface *intf, return 0;
destroy_chip: - usb6fire_chip_destroy(chip); + snd_card_free(card); return ret; }
@@ -182,7 +183,6 @@ static void usb6fire_chip_disconnect(struct usb_interface *intf)
chip->shutdown = true; usb6fire_chip_abort(chip); - usb6fire_chip_destroy(chip); } } }