From patchwork Wed Feb 6 02:04:17 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirsher, Jeffrey T" X-Patchwork-Id: 1037294 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=intel.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43vPs02Y6Rz9s3l for ; Wed, 6 Feb 2019 13:04:36 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729095AbfBFCEd (ORCPT ); Tue, 5 Feb 2019 21:04:33 -0500 Received: from mga18.intel.com ([134.134.136.126]:7292 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726767AbfBFCEc (ORCPT ); Tue, 5 Feb 2019 21:04:32 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Feb 2019 18:04:30 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,337,1544515200"; d="scan'208";a="114018916" Received: from jtkirshe-desk1.jf.intel.com ([134.134.177.96]) by orsmga006.jf.intel.com with ESMTP; 05 Feb 2019 18:04:30 -0800 From: Jeff Kirsher To: davem@davemloft.net Cc: Jeff Kirsher , netdev@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, Sasha Neftin , Kangjie Lu , Aaron Brown Subject: [net-next 07/14] e1000e: fix a missing check for return value Date: Tue, 5 Feb 2019 18:04:17 -0800 Message-Id: <20190206020424.12225-8-jeffrey.t.kirsher@intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190206020424.12225-1-jeffrey.t.kirsher@intel.com> References: <20190206020424.12225-1-jeffrey.t.kirsher@intel.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The change is based on the issue found by Kangjie Lu where we not checking the return value of a register read/write which could result in a NULL pointer dereference if the read/write fails. Since we are only trying to disable the far-end loopback, if the read and write of register fails, we do not want to bail out of the function. We just want to log that it failed to disable and continue on. CC: Sasha Neftin CC: Kangjie Lu Signed-off-by: Jeff Kirsher Tested-by: Aaron Brown --- .../net/ethernet/intel/e1000e/80003es2lan.c | 33 +++++++++++++------ 1 file changed, 23 insertions(+), 10 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/80003es2lan.c b/drivers/net/ethernet/intel/e1000e/80003es2lan.c index 257bd59bc9c6..f86d55657959 100644 --- a/drivers/net/ethernet/intel/e1000e/80003es2lan.c +++ b/drivers/net/ethernet/intel/e1000e/80003es2lan.c @@ -696,11 +696,16 @@ static s32 e1000_reset_hw_80003es2lan(struct e1000_hw *hw) ret_val = e1000_read_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, &kum_reg_data); - if (ret_val) - return ret_val; - kum_reg_data |= E1000_KMRNCTRLSTA_IBIST_DISABLE; - e1000_write_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, - kum_reg_data); + if (!ret_val) { + kum_reg_data |= E1000_KMRNCTRLSTA_IBIST_DISABLE; + ret_val = e1000_write_kmrn_reg_80003es2lan(hw, + E1000_KMRNCTRLSTA_INBAND_PARAM, + kum_reg_data); + if (ret_val) + e_dbg("Error disabling far-end loopback\n"); + } else { + e_dbg("Error disabling far-end loopback\n"); + } ret_val = e1000e_get_auto_rd_done(hw); if (ret_val) @@ -754,11 +759,19 @@ static s32 e1000_init_hw_80003es2lan(struct e1000_hw *hw) return ret_val; /* Disable IBIST slave mode (far-end loopback) */ - e1000_read_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, - &kum_reg_data); - kum_reg_data |= E1000_KMRNCTRLSTA_IBIST_DISABLE; - e1000_write_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, - kum_reg_data); + ret_val = + e1000_read_kmrn_reg_80003es2lan(hw, E1000_KMRNCTRLSTA_INBAND_PARAM, + &kum_reg_data); + if (!ret_val) { + kum_reg_data |= E1000_KMRNCTRLSTA_IBIST_DISABLE; + ret_val = e1000_write_kmrn_reg_80003es2lan(hw, + E1000_KMRNCTRLSTA_INBAND_PARAM, + kum_reg_data); + if (ret_val) + e_dbg("Error disabling far-end loopback\n"); + } else { + e_dbg("Error disabling far-end loopback\n"); + } /* Set the transmit descriptor write-back policy */ reg_data = er32(TXDCTL(0));