From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Yongjun Subject: [PATCH net-next] net: phy: mdio-bcm-unimac: fix potential NULL dereference in unimac_mdio_probe() Date: Thu, 11 Jan 2018 11:21:51 +0000 Message-ID: <1515669711-126459-1-git-send-email-weiyongjun1@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Cc: Wei Yongjun , , To: Andrew Lunn , Florian Fainelli Return-path: Received: from szxga04-in.huawei.com ([45.249.212.190]:4168 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933649AbeAKLPt (ORCPT ); Thu, 11 Jan 2018 06:15:49 -0500 Sender: netdev-owner@vger.kernel.org List-ID: platform_get_resource() may fail and return NULL, so we should better check it's return value to avoid a NULL pointer dereference a bit later in the code. This is detected by Coccinelle semantic patch. @@ expression pdev, res, n, t, e, e1, e2; @@ res = platform_get_resource(pdev, t, n); + if (!res) + return -EINVAL; ... when != res == NULL e = devm_ioremap(e1, res->start, e2); Signed-off-by: Wei Yongjun --- drivers/net/phy/mdio-bcm-unimac.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/phy/mdio-bcm-unimac.c b/drivers/net/phy/mdio-bcm-unimac.c index 08e0647..8d37066 100644 --- a/drivers/net/phy/mdio-bcm-unimac.c +++ b/drivers/net/phy/mdio-bcm-unimac.c @@ -205,6 +205,8 @@ static int unimac_mdio_probe(struct platform_device *pdev) return -ENOMEM; r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) + return -EINVAL; /* Just ioremap, as this MDIO block is usually integrated into an * Ethernet MAC controller register range