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 791BA31ED93; Sun, 7 Jun 2026 10:53:28 +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=1780829609; cv=none; b=lpAfLEEk0iJ2q7zDd/FZt44XWTeAWqzYHPquPCaFh52C8TRmk81XVJfvMpr9EBEYGHLnTNwBsMtUknSfqd36jHLwLse0uOk0ZLcaO0vlW/+NgTGmguxtioQ0L6ZPpb3Isce7BDC9/9j1JxZHU4Cf6kv7m/ms/8N+HUKBrJ7Ik68= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780829609; c=relaxed/simple; bh=31XNSCMGoqoj8j/S7EnFrG0AiCD8GGvvyogQ3DUuyt8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=syg5HwIPtVBKj4YDfWZpxS/PwuMjofKsbpuYhix27PxISv0ESUC9j1MPYcIKGiwqEmD/OGFr8lAkWMTZ4XjOj5qrzQgYE1W3YGLB5WHV7yaCIwZ+yZh+/TVOTz9JabvbJyAgNPWMs1+0tS4iUIgISC/s8xN4VSa8AxNtMibGa5w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=X38U5bNq; 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="X38U5bNq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 71ABF1F00893; Sun, 7 Jun 2026 10:53:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780829608; bh=oGOQo9o4nIBbjdaalmox/EF5FdOGPkplF0RvLy1jjf4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=X38U5bNqy0gg7r0BeAxvGa3T6k5yTQo6CGj7NHAQ/tg9mHEI1bfZ6Jf3KWij666N2 cupE9nuZNZHBUiE6dZBv1X8MYsW3xfF/Q3JqQUedsndMTKvuxtt9i1KzDhXC8a0yRL XtVtK7YI8dWgR1/uiBZy6Un4acQ4HzgNg6bwqoqU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrew Lunn , Johan Hovold Subject: [PATCH 6.18 239/315] USB: serial: mxuport: fix memory corruption with small endpoint Date: Sun, 7 Jun 2026 12:00:26 +0200 Message-ID: <20260607095736.347435396@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095727.528828913@linuxfoundation.org> References: <20260607095727.528828913@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: Johan Hovold commit 4085f0dbb1ce2251c9a5938d693de6593f0ab2bd upstream. Make sure that the bulk-out endpoint max packet size is at least eight bytes to avoid user-controlled slab corruption should a malicious device report a smaller size. Fixes: ee467a1f2066 ("USB: serial: add Moxa UPORT 12XX/14XX/16XX driver") Cc: stable@vger.kernel.org # 3.14 Cc: Andrew Lunn Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/mxuport.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/usb/serial/mxuport.c +++ b/drivers/usb/serial/mxuport.c @@ -962,6 +962,14 @@ static int mxuport_calc_num_ports(struct */ BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < 16); + /* + * The bulk-out buffers must be large enough for the four-byte header + * (and following data), but assume anything smaller than eight bytes + * is broken. + */ + if (usb_endpoint_maxp(epds->bulk_out[0]) < 8) + return -EINVAL; + for (i = 1; i < num_ports; ++i) epds->bulk_out[i] = epds->bulk_out[0];