[PATCH 6.18 017/333] ALSA: usb-audio: Check max frame size for implicit feedback mode, too

Greg Kroah-Hartman
2026-03-17T17:05:11Z

From: Takashi Iwai <tiwai@suse.de>

[ Upstream commit 7cb2a5422f5bbdf1cf32eae0eda41000485b9346 ]

When the packet sizes are taken from the capture stream in the
implicit feedback mode, the sizes might be larger than the upper
boundary defined by the descriptor. As already done for other
transfer modes, we have to cap the sizes accordingly at sending,
otherwise this would lead to an error in USB core at submission of
URBs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=221076
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20260225085233.316306-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
sound/usb/endpoint.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index eff3329d86b7e..77c4330d52953 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -221,6 +221,7 @@ int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,

packet = ctx->packet_size[idx];
if (packet) {
+ packet = min(packet, ep->maxframesize);
if (avail && packet >= avail)
return -EAGAIN;
return packet;
--
2.51.0