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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Ben Greear <greearb@candelatech.com>,
        Felix Fietkau <nbd@nbd.name>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.12 518/677] mt76: mt7915: fix tx skb dma unmap
Date:   Wed, 12 May 2021 16:49:24 +0200
Message-Id: <20210512144854.595338865@linuxfoundation.org>
In-Reply-To: <20210512144837.204217980@linuxfoundation.org>
References: <20210512144837.204217980@linuxfoundation.org>
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From: Felix Fietkau <nbd@nbd.name>

[ Upstream commit 7dcf3c04f0aca746517a77433b33d40868ca4749 ]

The first pointer in the txp needs to be unmapped as well, otherwise it will
leak DMA mapping entries

Reported-by: Ben Greear <greearb@candelatech.com>
Fixes: 27d5c528a7ca ("mt76: fix double DMA unmap of the first buffer on 7615/7915")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/wireless/mediatek/mt76/mt7915/mac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
index e5a258958ac9..b79d614aaad9 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
@@ -1091,7 +1091,7 @@ void mt7915_txp_skb_unmap(struct mt76_dev *dev,
 	int i;
 
 	txp = mt7915_txwi_to_txp(dev, t);
-	for (i = 1; i < txp->nbuf; i++)
+	for (i = 0; i < txp->nbuf; i++)
 		dma_unmap_single(dev->dev, le32_to_cpu(txp->buf[i]),
 				 le16_to_cpu(txp->len[i]), DMA_TO_DEVICE);
 }
-- 
2.30.2