From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: 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 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> (sfid-20171214_111344_989768_53968583) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: 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 --- 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; -- 2.14.1