From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1F53244AB6A; Tue, 21 Jul 2026 22:32:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784673141; cv=none; b=sINq/TaQf7vtp1xIKEVK05RcujJJWiCfSx3IFY6AP2JHQUTuBLlTcsqHxsJXo4D7LiOdxKErnrgHRC4V6ibWlvMO5mMQl6bj5THKwkek8QhsYZ0hAlw0mtTxemF7oa4CkCUASX4RabDjvYq/4UaRAZ25pifyyrvHPNr5ThUGTIA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784673141; c=relaxed/simple; bh=D07WKO34i4YRY8UrC/gekbHcmB9DAlCGDuZfmqCAACU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gLMy2FZmwr3nNvet2AyH4U1I54kTukHgKbX9M9X6/x3U8QSZa/582TIwluEtM5zwylLa8pyHh96W9cIZXj3uPHazysSZLss6qoyDIQFrstzxR70sB95JjmBCsI8VHp7pMFY6/oCeH0EBNo5n8t+lcbD+1AVtxI07U6T18ookbe4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=LhOUxV2Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="LhOUxV2Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F1B61F000E9; Tue, 21 Jul 2026 22:32:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784673140; bh=LFWJnQMXbW670JD0ZlZMdm4eJpruYgbqgrkbfoPB1B8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=LhOUxV2ZTAWwqQGGfhHfzzzFX4Z2fw9zT/iAvb0P6Remi5PXv5MKGRGVyPpKo9HYb SMs8fDT46gpqD76Iho4AuncU0tyMKRmPuQ6L0EGXbFjI6nSmKaLZgDnD2CqrZfrXFl 2M3fBR9d9P33hAmIsw3fbOInmhDnKLE+/E5y1juU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Maoyi Xie , Takashi Iwai Subject: [PATCH 5.10 051/699] ALSA: caiaq: fix out-of-bounds read in the Traktor Kontrol S4 input parser Date: Tue, 21 Jul 2026 17:16:50 +0200 Message-ID: <20260721152356.862117747@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152355.667394603@linuxfoundation.org> References: <20260721152355.667394603@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maoyi Xie commit f7f3f9fd81e7adbaa12c2e62ee07f0e094a543fd upstream. snd_usb_caiaq_tks4_dispatch() decodes the Traktor Kontrol S4 input stream in fixed 16-byte (TKS4_MSGBLOCK_SIZE) message blocks. On every iteration it advances buf and subtracts the block size while looping on "while (len)". len is urb->actual_length. That value is supplied by the device and is not guaranteed to be a multiple of 16. When a final short block leaves len between 1 and 15, the loop runs once more, reads up to buf[15], and then does "len -= TKS4_MSGBLOCK_SIZE". As len is unsigned this underflows to a huge value. The loop then keeps iterating and walking buf far past the end of the 512-byte ep4_in_buf, reading out of bounds until a bogus block id happens to be hit. Iterate only while a full message block is available. This stops the unsigned underflow and silently drops any trailing partial block, which carries no complete control value anyway. The sibling endpoint-4 parsers are not affected. The Traktor Kontrol X1 and Maschine arms in snd_usb_caiaq_ep4_reply_dispatch() floor urb->actual_length before dispatching. Fixes: 15c5ab607045 ("ALSA: snd-usb-caiaq: Add support for Traktor Kontrol S4") Cc: stable@vger.kernel.org Signed-off-by: Maoyi Xie Link: https://patch.msgid.link/178176259547.3343534.2724779296835237429@maoyixie.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/caiaq/input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/usb/caiaq/input.c +++ b/sound/usb/caiaq/input.c @@ -330,7 +330,7 @@ static void snd_usb_caiaq_tks4_dispatch( { struct device *dev = caiaqdev_to_dev(cdev); - while (len) { + while (len >= TKS4_MSGBLOCK_SIZE) { unsigned int i, block_id = (buf[0] << 8) | buf[1]; switch (block_id) {