From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6E95C43441 for ; Thu, 29 Nov 2018 14:25:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AFE002133F for ; Thu, 29 Nov 2018 14:25:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ejawPvOB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AFE002133F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733084AbeK3BbP (ORCPT ); Thu, 29 Nov 2018 20:31:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:58696 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731628AbeK3BbO (ORCPT ); Thu, 29 Nov 2018 20:31:14 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2A6062133F; Thu, 29 Nov 2018 14:25:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543501542; bh=Fl8QC35nLKL01udSNtNrrlaSAYp2kj0ueKcq2izToEM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ejawPvOBxoOaZNNkLEY9iiFDLn3X+f+SatyMomBl903WzdoI/zRXzKw1LRKIjRZOP dEVp1lM1E0sqyn+NDWA8XHVPFP4i1NsWxMYQfjJ3PKkswBf4wcB5N2L1UPZMzG5K6Z hE7vNhqPgPldRQrzrAXwQFIl0ulQH71VFvKQyCLs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Kleine-Budde Subject: [PATCH 4.14 039/100] can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb Date: Thu, 29 Nov 2018 15:12:09 +0100 Message-Id: <20181129140102.139885270@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181129140058.768942700@linuxfoundation.org> References: <20181129140058.768942700@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Kleine-Budde commit 7da11ba5c5066dadc2e96835a6233d56d7b7764a upstream. Prior to echoing a successfully transmitted CAN frame (by calling can_get_echo_skb()), CAN drivers have to put the CAN frame (by calling can_put_echo_skb() in the transmit function). These put and get function take an index as parameter, which is used to identify the CAN frame. A driver calling can_get_echo_skb() with a index not pointing to a skb is a BUG, so add an appropriate error message. Cc: linux-stable Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/dev.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) --- a/drivers/net/can/dev.c +++ b/drivers/net/can/dev.c @@ -479,6 +479,8 @@ EXPORT_SYMBOL_GPL(can_put_echo_skb); struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr) { struct can_priv *priv = netdev_priv(dev); + struct sk_buff *skb = priv->echo_skb[idx]; + struct canfd_frame *cf; if (idx >= priv->echo_skb_max) { netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", @@ -486,21 +488,20 @@ struct sk_buff *__can_get_echo_skb(struc return NULL; } - if (priv->echo_skb[idx]) { - /* Using "struct canfd_frame::len" for the frame - * length is supported on both CAN and CANFD frames. - */ - struct sk_buff *skb = priv->echo_skb[idx]; - struct canfd_frame *cf = (struct canfd_frame *)skb->data; - u8 len = cf->len; - - *len_ptr = len; - priv->echo_skb[idx] = NULL; - - return skb; + if (!skb) { + netdev_err(dev, "%s: BUG! Trying to echo non existing skb: can_priv::echo_skb[%u]\n", + __func__, idx); + return NULL; } - return NULL; + /* Using "struct canfd_frame::len" for the frame + * length is supported on both CAN and CANFD frames. + */ + cf = (struct canfd_frame *)skb->data; + *len_ptr = cf->len; + priv->echo_skb[idx] = NULL; + + return skb; } /*