6.12-stable review patch. If anyone has any objections, please let me know.
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From: Youngjun Lee yjjuny.lee@samsung.com
[ Upstream commit fb4e2a6e8f28a3c0ad382e363aeb9cd822007b8a ]
In snd_usb_get_audioformat_uac3(), the length value returned from snd_usb_ctl_msg() is used directly for memory allocation without validation. This length is controlled by the USB device.
The allocated buffer is cast to a uac3_cluster_header_descriptor and its fields are accessed without verifying that the buffer is large enough. If the device returns a smaller than expected length, this leads to an out-of-bounds read.
Add a length check to ensure the buffer is large enough for uac3_cluster_header_descriptor.
Signed-off-by: Youngjun Lee yjjuny.lee@samsung.com Fixes: 9a2fe9b801f5 ("ALSA: usb: initial USB Audio Device Class 3.0 support") Link: https://patch.msgid.link/20250623-uac3-oob-fix-v1-1-527303eaf40a@samsung.com Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- sound/usb/stream.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/sound/usb/stream.c b/sound/usb/stream.c index c1ea8844a46fc..aa91d63749f2c 100644 --- a/sound/usb/stream.c +++ b/sound/usb/stream.c @@ -987,6 +987,8 @@ snd_usb_get_audioformat_uac3(struct snd_usb_audio *chip, * and request Cluster Descriptor */ wLength = le16_to_cpu(hc_header.wLength); + if (wLength < sizeof(cluster)) + return NULL; cluster = kzalloc(wLength, GFP_KERNEL); if (!cluster) return ERR_PTR(-ENOMEM);