From nobody Wed Dec 31 15:04:41 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE2AEC4332F for ; Wed, 1 Nov 2023 12:36:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343659AbjKAMgM (ORCPT ); Wed, 1 Nov 2023 08:36:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235188AbjKAMgL (ORCPT ); Wed, 1 Nov 2023 08:36:11 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0747D11B; Wed, 1 Nov 2023 05:36:06 -0700 (PDT) Received: from dggpemm500011.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4SL5y36YB1zrTPC; Wed, 1 Nov 2023 20:32:59 +0800 (CST) Received: from huawei.com (10.175.104.170) by dggpemm500011.china.huawei.com (7.185.36.110) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Wed, 1 Nov 2023 20:36:01 +0800 From: Ren Mingshuai To: CC: , , , , , , Subject: [PATCH] net: usbnet: Fix potential NULL pointer dereference Date: Wed, 1 Nov 2023 20:35:59 +0800 Message-ID: <20231101123559.210756-1-renmingshuai@huawei.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.104.170] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500011.china.huawei.com (7.185.36.110) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 23ba07991dad said SKB can be NULL without describing the triggering scenario. Always Check it before dereference to void potential NULL pointer dereference. Fix smatch warning: drivers/net/usb/usbnet.c:1380 usbnet_start_xmit() error: we previously assu= med 'skb' could be null (see line 1359) Signed-off-by: Ren Mingshuai --- drivers/net/usb/usbnet.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 64a9a80b2309..386cb1a4ff03 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1374,6 +1374,11 @@ netdev_tx_t usbnet_start_xmit (struct sk_buff *skb, } } =20 + if (!skb) { + netif_dbg(dev, tx_err, dev->net, "tx skb is NULL\n"); + goto drop; + } + if (!(urb =3D usb_alloc_urb (0, GFP_ATOMIC))) { netif_dbg(dev, tx_err, dev->net, "no urb\n"); goto drop; --=20 2.33.0