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 6B1C8566C53; Wed, 9 Sep 2026 14:14:07 +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=1788963248; cv=none; b=NRDHysAfblMswkOPacGaZPbZmMxzRYltl3VSvO0L56Mq1SKTkPVdHbta7vE00C0UHSq4GHL2TMh0UX3r1s7Ff2/LUGLQqD6BfWy/6cVKjqkL5f3BHnlW6KcD58790sbpzlpJOs/ay+uAkZkePUsfFfDCltoddMTpZsa+BPd4p7E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788963248; c=relaxed/simple; bh=SDHG6zTd6ZvgVF3h04q08aa1HigfmzUDEz/caB0bkJw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NPrMCkSG7XTXatz13OPQIgF5jOzw42gl3C8Dvq6T/ZSOlZeKxs8ge9XvA3gZ8lzrnLG8bi1+xrKSqZ3Xqy4OfRlUIgajucLQeys/SvnZpAbK75yPYp6Hz+ZKs6PGAVGfwAs5R0PfJO/2RY3dOUELLLmcpDZnVUvdNQdrEuI/3sU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RqpkS5y9; 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="RqpkS5y9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B29D71F00A3A; Wed, 9 Sep 2026 14:14:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788963247; bh=DirP6V2fHkBYtZAeJjyEhfD4kQt9p0SLOHJ6mPVPnL8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RqpkS5y93QABBoCMcz8PTrqchQxJw0MsDrBAhKHXsy7Zdv00KS0VPJdh2a47gz2a7 QUWCw7yHU17nRJRRXWXsT1jsj6rnr+HZxeridQomLuswh1fJHH6HQC2lctRlpfF5Yl aGjN+BLi0jry8V61RSJey1Y1/sxxM4AaJNcxKotY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, HyeongJun An , Takashi Iwai Subject: [PATCH 6.18 014/583] ALSA: usb-audio: fix OOB write in snd_usbmidi_us122l_output() Date: Wed, 9 Sep 2026 15:34:59 +0200 Message-ID: <20260909134238.296931302@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: HyeongJun An commit e4637ce34607f1733a34a57294966d26b263e626 upstream. The snd_usbmidi_us122l_output() picks a count of 2 on anything slower than high speed and never relates it to ep->max_transfer. The URB buffer holds exactly max_transfer bytes, so a device declaring a one byte bulk endpoint takes two bytes from snd_rawmidi_transmit(), and the memset that pads the rest computes 1 - 2 in int and wraps to SIZE_MAX. Only 0x800e and 0x800f are pinned to nine bytes. The US-122MKII at 0x0644:0x8021 falls to the default and takes usb_maxpacket(), which the USB core only clamps downward. The akai and novation output ops in this file were given the same guard recently. Do the same here. Fixes: 030a07e44129 ("ALSA: Add USB US122L driver") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-5 Signed-off-by: HyeongJun An Link: https://patch.msgid.link/20260901090409.1478573-1-sammiee5311@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/midi.c | 2 ++ 1 file changed, 2 insertions(+) --- a/sound/usb/midi.c +++ b/sound/usb/midi.c @@ -967,6 +967,8 @@ static void snd_usbmidi_us122l_output(st default: count = 2; } + if (ep->max_transfer < count) + return; count = snd_rawmidi_transmit(ep->ports[0].substream, urb->transfer_buffer, count);