2021-02-16 13:55:53

by Felix Fietkau

[permalink] [raw]
Subject: [PATCH 5.12 2/2] mt76: mt7915: only modify tx buffer list after allocating tx token id

Modifying the tx buffer list too early can leak DMA mappings

Signed-off-by: Felix Fietkau <[email protected]>
---
drivers/net/wireless/mediatek/mt76/mt7915/mac.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
index eb889f8d6fea..e5a258958ac9 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
@@ -967,11 +967,6 @@ int mt7915_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
}
txp->nbuf = nbuf;

- /* pass partial skb header to fw */
- tx_info->buf[1].len = MT_CT_PARSE_LEN;
- tx_info->buf[1].skip_unmap = true;
- tx_info->nbuf = MT_CT_DMA_BUF_NUM;
-
txp->flags = cpu_to_le16(MT_CT_INFO_APPLY_TXD | MT_CT_INFO_FROM_HOST);

if (!key)
@@ -1009,6 +1004,11 @@ int mt7915_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
txp->rept_wds_wcid = cpu_to_le16(0x3ff);
tx_info->skb = DMA_DUMMY_DATA;

+ /* pass partial skb header to fw */
+ tx_info->buf[1].len = MT_CT_PARSE_LEN;
+ tx_info->buf[1].skip_unmap = true;
+ tx_info->nbuf = MT_CT_DMA_BUF_NUM;
+
return 0;
}

--
2.28.0