From patchwork Tue May 12 17:13:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin Ian King X-Patchwork-Id: 1288643 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=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49M4Cb4vqBz9sSg for ; Wed, 13 May 2020 03:14:03 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728258AbgELROA (ORCPT ); Tue, 12 May 2020 13:14:00 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43842 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725938AbgELRN7 (ORCPT ); Tue, 12 May 2020 13:13:59 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jYYTb-00026T-Sc; Tue, 12 May 2020 17:13:55 +0000 From: Colin King To: Solarflare linux maintainers , Edward Cree , Martin Habets , "David S . Miller" , netdev@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH][next] sfc: fix dereference of table before it is null checked Date: Tue, 12 May 2020 18:13:55 +0100 Message-Id: <20200512171355.221810-1-colin.king@canonical.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Colin Ian King Currently pointer table is being dereferenced on a null check of table->must_restore_filters before it is being null checked, leading to a potential null pointer dereference issue. Fix this by null checking table before dereferencing it when checking for a null table->must_restore_filters. Addresses-Coverity: ("Dereference before null check") Fixes: e4fe938cff04 ("sfc: move 'must restore' flags out of ef10-specific nic_data") Signed-off-by: Colin Ian King Acked-by: Edward Cree --- drivers/net/ethernet/sfc/mcdi_filters.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/net/ethernet/sfc/mcdi_filters.c b/drivers/net/ethernet/sfc/mcdi_filters.c index 88de95a8c08c..455a62814fb9 100644 --- a/drivers/net/ethernet/sfc/mcdi_filters.c +++ b/drivers/net/ethernet/sfc/mcdi_filters.c @@ -1369,10 +1369,7 @@ void efx_mcdi_filter_table_restore(struct efx_nic *efx) WARN_ON(!rwsem_is_locked(&efx->filter_sem)); - if (!table->must_restore_filters) - return; - - if (!table) + if (!table || !table->must_restore_filters) return; down_write(&table->lock);