diff options
author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2020-11-19 09:51:27 +0800 |
---|---|---|
committer | Kalle Valo <kvalo@codeaurora.org> | 2020-11-24 17:06:34 +0200 |
commit | 6df3c293d284655c72c1a72356ce4d32217a9c54 (patch) | |
tree | a1385980901f9a21769761486ef4afe369d3ae80 | |
parent | 00331758137245fd3478404ee81de40dfcb3b7de (diff) |
rtlwifi: rtl8188ee: avoid accessing the data mapped to streaming DMA
In rtl88ee_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on
line 677:
dma_addr_t mapping = dma_map_single(..., skb->data, ...);
On line 680, skb->data is assigned to hdr after cast:
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
Then hdr->frame_control is accessed on line 681:
__le16 fc = hdr->frame_control;
This DMA access may cause data inconsistency between CPU and hardwre.
To fix this bug, hdr->frame_control is accessed before the DMA mapping.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201119015127.12033-1-baijiaju1990@gmail.com
-rw-r--r-- | drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c index b9775eec4c54..c948dafa0c80 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8188ee/trx.c @@ -674,12 +674,12 @@ void rtl88ee_tx_fill_cmddesc(struct ieee80211_hw *hw, u8 fw_queue = QSLT_BEACON; __le32 *pdesc = (__le32 *)pdesc8; - dma_addr_t mapping = dma_map_single(&rtlpci->pdev->dev, skb->data, - skb->len, DMA_TO_DEVICE); - struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data); __le16 fc = hdr->frame_control; + dma_addr_t mapping = dma_map_single(&rtlpci->pdev->dev, skb->data, + skb->len, DMA_TO_DEVICE); + if (dma_mapping_error(&rtlpci->pdev->dev, mapping)) { rtl_dbg(rtlpriv, COMP_SEND, DBG_TRACE, "DMA mapping error\n"); |