diff options
| author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2020-11-19 09:51:51 +0800 |
|---|---|---|
| committer | Kalle Valo <kvalo@codeaurora.org> | 2020-11-24 17:06:35 +0200 |
| commit | c7ba0ea0df370975a484c30e711e8a483c1b96a4 (patch) | |
| tree | fed7911472c64fdf6c943b2f96c2bd9b211066e8 | |
| parent | 6df3c293d284655c72c1a72356ce4d32217a9c54 (diff) | |
rtlwifi: rtl8192ce: avoid accessing the data mapped to streaming DMA
In rtl92ce_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on
line 530:
dma_addr_t mapping = dma_map_single(..., skb->data, ...);
On line 533, 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 534:
__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/20201119015151.12110-1-baijiaju1990@gmail.com
| -rw-r--r-- | drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c index c0635309a92d..4165175cf5c0 100644 --- a/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c +++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192ce/trx.c @@ -527,12 +527,12 @@ void rtl92ce_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"); |