From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A6DBC433E0 for ; Mon, 8 Jun 2020 23:42:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 538AD20659 for ; Mon, 8 Jun 2020 23:42:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591659744; bh=MNQ8mx7/YoL+DE/atTfoj3dmjqjoE2lBS0qY/fSvAME=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Nqd+NaSk/DBpUEwqwTWPuKmaJz1948xC8vc9aQBT6/zCjj3TWQnTbq/Ibix9Kievm N0M71fMKO8Kil90lVBiDc5CStoP6WYcM8QXsFa3XBdV9tAP1pdY8z5DCqZZT1jDG4r GGPSJEcyq0CBTohIa6rYecBewPDNdYfzna+Geuos= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732234AbgFHXmO (ORCPT ); Mon, 8 Jun 2020 19:42:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:55782 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732128AbgFHX12 (ORCPT ); Mon, 8 Jun 2020 19:27:28 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0D84620801; Mon, 8 Jun 2020 23:27:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591658847; bh=MNQ8mx7/YoL+DE/atTfoj3dmjqjoE2lBS0qY/fSvAME=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PWl0N3ObRZmp6MvqB0ecHsJ2cm8poHQ+zJfu/NL/YtqKL0mJsJdccwfhwuNIWBfjg TGKwWMtqbU+tb1G/QFM1fd4rxhy+/1Bw/KE76VT//DpzZScAndBprRkBFpF9cIqK/N uxbhgn2qcWt0O/1im1yNa66sdKZ3vp0wCI923ywI= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Kalle Valo , Sasha Levin , linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 35/50] rtlwifi: Fix a double free in _rtl_usb_tx_urb_setup() Date: Mon, 8 Jun 2020 19:26:25 -0400 Message-Id: <20200608232640.3370262-35-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608232640.3370262-1-sashal@kernel.org> References: <20200608232640.3370262-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Dan Carpenter [ Upstream commit beb12813bc75d4a23de43b85ad1c7cb28d27631e ] Seven years ago we tried to fix a leak but actually introduced a double free instead. It was an understandable mistake because the code was a bit confusing and the free was done in the wrong place. The "skb" pointer is freed in both _rtl_usb_tx_urb_setup() and _rtl_usb_transmit(). The free belongs _rtl_usb_transmit() instead of _rtl_usb_tx_urb_setup() and I've cleaned the code up a bit to hopefully make it more clear. Fixes: 36ef0b473fbf ("rtlwifi: usb: add missing freeing of skbuff") Signed-off-by: Dan Carpenter Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20200513093951.GD347693@mwanda Signed-off-by: Sasha Levin --- drivers/net/wireless/realtek/rtlwifi/usb.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/realtek/rtlwifi/usb.c b/drivers/net/wireless/realtek/rtlwifi/usb.c index 1f02461de261..93b22a5b6878 100644 --- a/drivers/net/wireless/realtek/rtlwifi/usb.c +++ b/drivers/net/wireless/realtek/rtlwifi/usb.c @@ -927,10 +927,8 @@ static struct urb *_rtl_usb_tx_urb_setup(struct ieee80211_hw *hw, WARN_ON(NULL == skb); _urb = usb_alloc_urb(0, GFP_ATOMIC); - if (!_urb) { - kfree_skb(skb); + if (!_urb) return NULL; - } _rtl_install_trx_info(rtlusb, skb, ep_num); usb_fill_bulk_urb(_urb, rtlusb->udev, usb_sndbulkpipe(rtlusb->udev, ep_num), skb->data, skb->len, _rtl_tx_complete, skb); @@ -945,7 +943,6 @@ static void _rtl_usb_transmit(struct ieee80211_hw *hw, struct sk_buff *skb, struct rtl_usb *rtlusb = rtl_usbdev(rtl_usbpriv(hw)); u32 ep_num; struct urb *_urb = NULL; - struct sk_buff *_skb = NULL; WARN_ON(NULL == rtlusb->usb_tx_aggregate_hdl); if (unlikely(IS_USB_STOP(rtlusb))) { @@ -955,8 +952,7 @@ static void _rtl_usb_transmit(struct ieee80211_hw *hw, struct sk_buff *skb, return; } ep_num = rtlusb->ep_map.ep_mapping[qnum]; - _skb = skb; - _urb = _rtl_usb_tx_urb_setup(hw, _skb, ep_num); + _urb = _rtl_usb_tx_urb_setup(hw, skb, ep_num); if (unlikely(!_urb)) { RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG, "Can't allocate urb. Drop skb!\n"); -- 2.25.1