[PATCH AUTOSEL 5.11 02/61] mt76: mt7915: only modify tx buffer list after allocating tx token id

From: Sasha Levin
Date: Tue Mar 16 2021 - 20:56:31 EST


From: Felix Fietkau <nbd@xxxxxxxx>

[ Upstream commit 94f0e6256c2ab6803c935634aa1f653174c94879 ]

Modifying the tx buffer list too early can leak DMA mappings

Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210216135119.23809-2-nbd@xxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 1b4d65310b88..c9dd6867e125 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mac.c
@@ -957,11 +957,6 @@ 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)
@@ -999,6 +994,11 @@ 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;
}

--
2.30.1