From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757677AbcHYGw3 (ORCPT ); Thu, 25 Aug 2016 02:52:29 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:56670 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752958AbcHYGw2 (ORCPT ); Thu, 25 Aug 2016 02:52:28 -0400 From: Colin King To: Yisen Zhuang , Salil Mehta , "David S . Miller" , Lisheng , netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] net: hns: dereference ppe_cb->ppe_common_cb if it is non-null Date: Thu, 25 Aug 2016 07:51:10 +0100 Message-Id: <20160825065110.10104-1-colin.king@canonical.com> X-Mailer: git-send-email 2.9.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Colin Ian King ppe_cb->ppe_common_cb is being dereferenced before a null check is being made on it. If ppe_cb->ppe_common_cb is null then we end up with a null pointer dereference when assigning dsaf_dev. Fix this by moving the initialisation of dsaf_dev once we know ppe_cb->ppe_common_cb is OK to dereference. Signed-off-by: Colin Ian King --- drivers/net/ethernet/hisilicon/hns/hns_dsaf_ppe.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_ppe.c b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_ppe.c index ff8b6a4..6ea8722 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_dsaf_ppe.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_dsaf_ppe.c @@ -328,9 +328,10 @@ static void hns_ppe_init_hw(struct hns_ppe_cb *ppe_cb) static void hns_ppe_uninit_hw(struct hns_ppe_cb *ppe_cb) { u32 port; - struct dsaf_device *dsaf_dev = ppe_cb->ppe_common_cb->dsaf_dev; if (ppe_cb->ppe_common_cb) { + struct dsaf_device *dsaf_dev = ppe_cb->ppe_common_cb->dsaf_dev; + port = ppe_cb->index; dsaf_dev->misc_op->ppe_srst(dsaf_dev, port, 0); } -- 2.9.3