From patchwork Mon Mar 29 07:55:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 411489 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 36A40C433EB for ; Mon, 29 Mar 2021 08:18:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D5A161960 for ; Mon, 29 Mar 2021 08:18:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231876AbhC2IS2 (ORCPT ); Mon, 29 Mar 2021 04:18:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:58912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233351AbhC2IRc (ORCPT ); Mon, 29 Mar 2021 04:17:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 382C1619AB; Mon, 29 Mar 2021 08:17:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617005840; bh=shqrO44CNEbaZ037D9y/bUKPrsaXZ/uQPtoYKuIQUlE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FOKSkHbukGiK1FcNBxQ4tgve5F83BwPX3QyP38btQmUplijPDqjmFaP/5LVhaAOEg YSHt1PjYBaZrOvxeF7KKuJkIoG1SEkP9/7xV5gGDKbQ4V/C4CjbZExw/ewtHAzbE0v Tmv5y/QcLonmAPwSvbD5+FYksvRsW8IgygRNKRdQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Felix Fietkau , Kalle Valo , Sasha Levin Subject: [PATCH 5.10 003/221] mt76: fix tx skb error handling in mt76_dma_tx_queue_skb Date: Mon, 29 Mar 2021 09:55:34 +0200 Message-Id: <20210329075629.288629093@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210329075629.172032742@linuxfoundation.org> References: <20210329075629.172032742@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Felix Fietkau [ Upstream commit ae064fc0e32a4d28389086d9f4b260a0c157cfee ] When running out of room in the tx queue after calling drv->tx_prepare_skb, the buffer list will already have been modified on MT7615 and newer drivers. This can leak a DMA mapping and will show up as swiotlb allocation failures on x86. Fix this by moving the queue length check further up. This is less accurate, since it can overestimate the needed room in the queue on MT7615 and newer, but the difference is small enough to not matter in practice. Signed-off-by: Felix Fietkau Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20210216135119.23809-1-nbd@nbd.name Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt76/dma.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c index 262c40dc14a6..665a03ebf9ef 100644 --- a/drivers/net/wireless/mediatek/mt76/dma.c +++ b/drivers/net/wireless/mediatek/mt76/dma.c @@ -355,7 +355,6 @@ mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid, }; struct ieee80211_hw *hw; int len, n = 0, ret = -ENOMEM; - struct mt76_queue_entry e; struct mt76_txwi_cache *t; struct sk_buff *iter; dma_addr_t addr; @@ -397,6 +396,11 @@ mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid, } tx_info.nbuf = n; + if (q->queued + (tx_info.nbuf + 1) / 2 >= q->ndesc - 1) { + ret = -ENOMEM; + goto unmap; + } + dma_sync_single_for_cpu(dev->dev, t->dma_addr, dev->drv->txwi_size, DMA_TO_DEVICE); ret = dev->drv->tx_prepare_skb(dev, txwi, qid, wcid, sta, &tx_info); @@ -405,11 +409,6 @@ mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid, if (ret < 0) goto unmap; - if (q->queued + (tx_info.nbuf + 1) / 2 >= q->ndesc - 1) { - ret = -ENOMEM; - goto unmap; - } - return mt76_dma_add_buf(dev, q, tx_info.buf, tx_info.nbuf, tx_info.info, tx_info.skb, t); @@ -425,9 +424,7 @@ mt76_dma_tx_queue_skb(struct mt76_dev *dev, enum mt76_txq_id qid, dev->test.tx_done--; #endif - e.skb = tx_info.skb; - e.txwi = t; - dev->drv->tx_complete_skb(dev, &e); + dev_kfree_skb(tx_info.skb); mt76_put_txwi(dev, t); return ret; }