[PATCH 5.15 004/530] ALSA: usb-audio: Fix potential memory leaks

From: Greg Kroah-Hartman
Date: Mon Oct 24 2022 - 09:42:18 EST


From: Takashi Iwai <tiwai@xxxxxxx>

commit 6382da0828995af87aa8b8bef28cc61aceb4aff3 upstream.

When the driver hits -ENOMEM at allocating a URB or a buffer, it
aborts and goes to the error path that releases the all previously
allocated resources. However, when -ENOMEM hits at the middle of the
sync EP URB allocation loop, the partially allocated URBs might be
left without released, because ep->nurbs is still zero at that point.

Fix it by setting ep->nurbs at first, so that the error handler loops
over the full URB list.

Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220930100151.19461-1-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/usb/endpoint.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -1223,6 +1223,7 @@ static int sync_ep_set_params(struct snd
if (!ep->syncbuf)
return -ENOMEM;

+ ep->nurbs = SYNC_URBS;
for (i = 0; i < SYNC_URBS; i++) {
struct snd_urb_ctx *u = &ep->urb[i];
u->index = i;
@@ -1242,8 +1243,6 @@ static int sync_ep_set_params(struct snd
u->urb->complete = snd_complete_urb;
}

- ep->nurbs = SYNC_URBS;
-
return 0;

out_of_memory: