From patchwork Fri Sep 15 19:20:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 13387571 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D0A5719BB2 for ; Fri, 15 Sep 2023 19:19:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9ABCCC433C8; Fri, 15 Sep 2023 19:19:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694805559; bh=O6zKBde/jQeUo4lppmCpOky1iZxcXTpe2NdXo5CtT+k=; h=Date:From:To:Cc:Subject:From; b=udBm1XbCL5/0ifCYnkf2qJ3cbdstwMq/rAxd67WQQcp3+EJWMFabpDIPT3InuAgxl dc4t+yxDE9wFhQVq2rU1ehkXtstoW65Udmk3iflTeYs+8ickHVOnVJNwXZAS6nmKh5 Gf4VvoP75j65FeMbiMji31mczSwpzVw+xUkiQdxs9gbfFj9Eqn5FOZ190lCOcwA7p5 1YoDh5XBc0tmkPPQ5t7GUgJVnkr/+x2lbXVtQJSrtQhZRB9Nos9HsIRtqRJSPRT8zk lkEduTNvCu53RsDrDUzghpv2wL0VrPPJ4k/XHROZuimlWqt9TJ5GWUKQlLDG03xFNX hzac0nz0k+iwg== Date: Fri, 15 Sep 2023 13:20:14 -0600 From: "Gustavo A. R. Silva" To: Duncan Sands , Greg Kroah-Hartman , "Gustavo A. R. Silva" Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org Subject: [PATCH][next] usb: atm: Use size_add() in call to struct_size() Message-ID: Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline If, for any reason, the open-coded arithmetic causes a wraparound, the protection that `struct_size()` adds against potential integer overflows is defeated. Fix this by hardening call to `struct_size()` with `size_add()`. Fixes: b626871a7cda ("usb: atm: Use struct_size() helper") Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook --- drivers/usb/atm/usbatm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/atm/usbatm.c b/drivers/usb/atm/usbatm.c index 1cdb8758ae01..2da6615fbb6f 100644 --- a/drivers/usb/atm/usbatm.c +++ b/drivers/usb/atm/usbatm.c @@ -1018,7 +1018,8 @@ int usbatm_usb_probe(struct usb_interface *intf, const struct usb_device_id *id, size_t size; /* instance init */ - size = struct_size(instance, urbs, num_rcv_urbs + num_snd_urbs); + size = struct_size(instance, urbs, + size_add(num_rcv_urbs, num_snd_urbs)); instance = kzalloc(size, GFP_KERNEL); if (!instance) return -ENOMEM;