From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jimmy Assarsson Subject: [PATCH 2/3] can: kvaser_usb: Fix comparison bug in kvaser_usb_read_bulk_callback() Date: Tue, 21 Nov 2017 08:22:27 +0100 Message-ID: <20171121072228.7570-3-jimmyassarsson@gmail.com> References: <20171121072228.7570-1-jimmyassarsson@gmail.com> Return-path: Received: from mail-lf0-f67.google.com ([209.85.215.67]:46704 "EHLO mail-lf0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753156AbdKUHWr (ORCPT ); Tue, 21 Nov 2017 02:22:47 -0500 Received: by mail-lf0-f67.google.com with SMTP id g35so12882088lfi.13 for ; Mon, 20 Nov 2017 23:22:47 -0800 (PST) In-Reply-To: <20171121072228.7570-1-jimmyassarsson@gmail.com> Sender: linux-can-owner@vger.kernel.org List-ID: To: linux-can@vger.kernel.org Cc: Jimmy Assarsson The conditon in the while-loop becomes true when actual_length is less than 2 (MSG_HEADER_LEN). In best case we end up with a former, already dispatched msg, that got msg->len greater than actual_length. This will result in a "Format error" error printout. Problem seen when unplugging a Kvaser USB device connected to a vbox guest. warning: comparison between signed and unsigned integer expressions [-Wsign-compare] Signed-off-by: Jimmy Assarsson --- drivers/net/can/usb/kvaser_usb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c index 075644591498..d87e330a20b3 100644 --- a/drivers/net/can/usb/kvaser_usb.c +++ b/drivers/net/can/usb/kvaser_usb.c @@ -1334,7 +1334,7 @@ static void kvaser_usb_read_bulk_callback(struct urb *urb) goto resubmit_urb; } - while (pos <= urb->actual_length - MSG_HEADER_LEN) { + while (pos <= (int)(urb->actual_length - MSG_HEADER_LEN)) { msg = urb->transfer_buffer + pos; /* The Kvaser firmware can only read and write messages that -- 2.15.0