[PATCH 5.15 32/76] ALSA: usb-audio: Apply mutex around snd_usb_endpoint_set_params()

From: Sasha Levin
Date: Wed Mar 13 2024 - 13:29:01 EST


From: Takashi Iwai <tiwai@xxxxxxx>

[ Upstream commit a74f8d0aa902ca494676b79226e0b5a1747b81d4 ]

The protection with chip->mutex was lost after splitting
snd_usb_endpoint_set_params() and snd_usb_endpoint_prepare().
Apply the same mutex again to the former function.

Fixes: 2be79d586454 ("ALSA: usb-audio: Split endpoint setups for hw_params and prepare (take#2)")
Link: https://lore.kernel.org/r/20221009104212.18877-3-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Stable-dep-of: 7822baa844a8 ("ALSA: usb-audio: add quirk for RODE NT-USB+")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/usb/endpoint.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index 2d3f814d067b5..486ef6b022552 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -1339,10 +1339,11 @@ int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
const struct audioformat *fmt = ep->cur_audiofmt;
int err;

+ mutex_lock(&chip->mutex);
/* release old buffers, if any */
err = release_urbs(ep, false);
if (err < 0)
- return err;
+ goto unlock;

ep->datainterval = fmt->datainterval;
ep->maxpacksize = fmt->maxpacksize;
@@ -1380,13 +1381,16 @@ int snd_usb_endpoint_set_params(struct snd_usb_audio *chip,
usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);

if (err < 0)
- return err;
+ goto unlock;

/* some unit conversions in runtime */
ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;

- return update_clock_ref_rate(chip, ep);
+ err = update_clock_ref_rate(chip, ep);
+ unlock:
+ mutex_unlock(&chip->mutex);
+ return err;
}

static int init_sample_rate(struct snd_usb_audio *chip,
--
2.43.0