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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 0EF33C43441 for ; Wed, 28 Nov 2018 09:06:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1AA92086B for ; Wed, 28 Nov 2018 09:06:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="YAYM3mHK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C1AA92086B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=163.com 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 S1727952AbeK1UHX (ORCPT ); Wed, 28 Nov 2018 15:07:23 -0500 Received: from m12-16.163.com ([220.181.12.16]:52473 "EHLO m12-16.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727413AbeK1UHX (ORCPT ); Wed, 28 Nov 2018 15:07:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=NB6s/+V5cIqzeFNbhZ h4CQ5aEFBxxXAHiaDRAdx3YKI=; b=YAYM3mHKD4PLabk3UJHKIfxRuudTfJiL1U zbjZwUlhYp3Jv58d15xxHDEW+BXS5bNcKqSTfvHPBK1WDc172woL4liTJ5NZOEBw mtzWKEeBbbBUo3Egekz9QbEZn8L6d0zb+eAtOteWjMkyWsq65vuAmNaE/G1h6yYB EmOyUYQdU= Received: from bp.localdomain (unknown [106.120.213.96]) by smtp12 (Coremail) with SMTP id EMCowAD3yaiGWv5beShcAQ--.20921S3; Wed, 28 Nov 2018 17:06:21 +0800 (CST) From: Pan Bian To: Tom Lendacky , "David S. Miller" Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Pan Bian Subject: [PATCH V2] amd-xgbe: set skb to NULL after freeing it Date: Wed, 28 Nov 2018 17:06:15 +0800 Message-Id: <1543395975-25339-1-git-send-email-bianpan2016@163.com> X-Mailer: git-send-email 2.7.4 X-CM-TRANSID: EMCowAD3yaiGWv5beShcAQ--.20921S3 X-Coremail-Antispam: 1Uf129KBjvJXoW7Cw1DKw13CF1xGrWDXrW7twb_yoW8JF47pa yUWryxJw1ktr42qa18Ja1IvF15ta1ktFW5Kr95u3WrZ3Z0yry2vrykK34jkFWjkFWkGa1a qr47urs3W3ZxJ3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07j17K3UUUUU= X-Originating-IP: [106.120.213.96] X-CM-SenderInfo: held01tdqsiiqw6rljoofrz/xtbBUQ0NclaD0V8ykwAAsZ Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The buffer skb is freed via dev_kfree_skb in a loop. After freeing skb, the value of packet_count is updated via packet_count++. If packet_count happens to equal the upper bound budget, the loop will be broken and skb may be assigned to rdata->state.skb. Resulting that rdata->state.skb may point to a freed memory chunk. To fix this, the patch sets skb to NULL after dev_kfree_skb(skb). Signed-off-by: Pan Bian --- V2: correct the commit log --- drivers/net/ethernet/amd/xgbe/xgbe-drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c index 0cc911f..ac6b82d 100644 --- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c +++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c @@ -2754,6 +2754,7 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget) netif_err(pdata, rx_err, netdev, "error in received packet\n"); dev_kfree_skb(skb); + skb = NULL; goto next_packet; } @@ -2806,6 +2807,7 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget) netif_err(pdata, rx_err, netdev, "packet length exceeds configured MTU\n"); dev_kfree_skb(skb); + skb = NULL; goto next_packet; } -- 2.7.4