From patchwork Wed Jul 15 07:09:44 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 495465 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id DF03F1402AC for ; Wed, 15 Jul 2015 17:11:05 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752661AbbGOHLB (ORCPT ); Wed, 15 Jul 2015 03:11:01 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:59830 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752161AbbGOHJ7 (ORCPT ); Wed, 15 Jul 2015 03:09:59 -0400 Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=hardanger.blackshift.org) by metis.ext.pengutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1ZFExX-0004f9-40; Wed, 15 Jul 2015 07:10:19 +0200 From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, linux-can@vger.kernel.org, kernel@pengutronix.de, Marc Kleine-Budde , Wolfgang Grandegger Subject: [PATCH 07/12] can: cc770: don't touch skb after netif_rx() Date: Wed, 15 Jul 2015 09:09:44 +0200 Message-Id: <1436944189-26618-8-git-send-email-mkl@pengutronix.de> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1436944189-26618-1-git-send-email-mkl@pengutronix.de> References: <1436944189-26618-1-git-send-email-mkl@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org There is no guarantee that the skb is in the same state after calling net_receive_skb() or netif_rx(). It might be freed or reused. Not really harmful as its a read access, except you turn on the proper debugging options which catch a use after free. Cc: Wolfgang Grandegger Signed-off-by: Marc Kleine-Budde --- drivers/net/can/cc770/cc770.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/can/cc770/cc770.c b/drivers/net/can/cc770/cc770.c index c11d44984036..70a8cbb29e75 100644 --- a/drivers/net/can/cc770/cc770.c +++ b/drivers/net/can/cc770/cc770.c @@ -504,10 +504,10 @@ static void cc770_rx(struct net_device *dev, unsigned int mo, u8 ctrl1) for (i = 0; i < cf->can_dlc; i++) cf->data[i] = cc770_read_reg(priv, msgobj[mo].data[i]); } - netif_rx(skb); stats->rx_packets++; stats->rx_bytes += cf->can_dlc; + netif_rx(skb); } static int cc770_err(struct net_device *dev, u8 status) @@ -584,10 +584,10 @@ static int cc770_err(struct net_device *dev, u8 status) } } - netif_rx(skb); stats->rx_packets++; stats->rx_bytes += cf->can_dlc; + netif_rx(skb); return 0; }