From: Bruno Randolf Date: Wed, 19 May 2010 01:18:16 +0000 (+0900) Subject: ath5k: consistently use rx_bufsize for RX DMA X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b5eae9ff5ba6d76de19286dd6429acd7cde3f79d;p=linux-beck.git ath5k: consistently use rx_bufsize for RX DMA We should use the same buffer size we set up for DMA also in the hardware descriptor. Previously we used common->rx_bufsize for setting up the DMA mapping, but used skb_tailroom(skb) for the size we tell to the hardware in the descriptor itself. The problem is that skb_tailroom(skb) can give us a larger value than the size we set up for DMA before. This allows the hardware to write into memory locations not set up for DMA. In practice this should rarely happen because all packets should be smaller than the maximum 802.11 packet size. On the tested platform rx_bufsize is 2528, and we allocated an skb of 2559 bytes length (including padding for cache alignment) but sbk_tailroom() was 2592. Just consistently use rx_bufsize for all RX DMA memory sizes. Also use the return value of the descriptor setup function. Cc: stable@kernel.org Signed-off-by: Bruno Randolf Reviewed-by: Luis R. Rodriguez Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c index 5f04cf38a5bc..cc6d41dec332 100644 --- a/drivers/net/wireless/ath/ath5k/base.c +++ b/drivers/net/wireless/ath/ath5k/base.c @@ -1214,6 +1214,7 @@ ath5k_rxbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf) struct ath5k_hw *ah = sc->ah; struct sk_buff *skb = bf->skb; struct ath5k_desc *ds; + int ret; if (!skb) { skb = ath5k_rx_skb_alloc(sc, &bf->skbaddr); @@ -1240,9 +1241,9 @@ ath5k_rxbuf_setup(struct ath5k_softc *sc, struct ath5k_buf *bf) ds = bf->desc; ds->ds_link = bf->daddr; /* link to self */ ds->ds_data = bf->skbaddr; - ah->ah_setup_rx_desc(ah, ds, - skb_tailroom(skb), /* buffer size */ - 0); + ret = ah->ah_setup_rx_desc(ah, ds, ah->common.rx_bufsize, 0); + if (ret) + return ret; if (sc->rxlink != NULL) *sc->rxlink = bf->daddr;