From patchwork Thu Dec 14 10:13:22 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin King X-Patchwork-Id: 10111747 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 11357602B3 for ; Thu, 14 Dec 2017 10:13:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EA77B29B06 for ; Thu, 14 Dec 2017 10:13:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DF09D29BE8; Thu, 14 Dec 2017 10:13:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9620629B06 for ; Thu, 14 Dec 2017 10:13:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751588AbdLNKN0 (ORCPT ); Thu, 14 Dec 2017 05:13:26 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:55248 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751071AbdLNKNZ (ORCPT ); Thu, 14 Dec 2017 05:13:25 -0500 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1ePQW3-0000sH-2w; Thu, 14 Dec 2017 10:13:23 +0000 From: Colin King To: Kalle Valo , Matthias Brugger , Lorenzo Bianconi , Felix Fietkau , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] mt76: fix memcpy to potential null pointer on failed allocation Date: Thu, 14 Dec 2017 10:13:22 +0000 Message-Id: <20171214101322.10178-1-colin.king@canonical.com> X-Mailer: git-send-email 2.14.1 MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Colin Ian King Currently if the allocation of skb fails and returns NULL then the call to skb_put will cause a null pointer dereference. Fix this by checking for a null skb and returning NULL. Note that calls to function mt76x2_mcu_msg_alloc don't directly check the null return but instead pass the NULL pointer to mt76x2_mcu_msg_send which checks for the NULL and returns ENOMEM in this case. Detected by CoverityScan, CID#1462624 ("Dereference null return value") Fixes: 7bc04215a66b ("mt76: add driver code for MT76x2e") Signed-off-by: Colin Ian King Acked-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/mt76x2_mcu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_mcu.c b/drivers/net/wireless/mediatek/mt76/mt76x2_mcu.c index d45737ee1412..15820b11f9db 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2_mcu.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2_mcu.c @@ -45,6 +45,8 @@ static struct sk_buff *mt76x2_mcu_msg_alloc(const void *data, int len) struct sk_buff *skb; skb = alloc_skb(len, GFP_KERNEL); + if (!skb) + return NULL; memcpy(skb_put(skb, len), data, len); return skb;