From 9f201a87831af9458df1eda65941c955f2da87ed Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Fri, 27 Mar 2009 07:50:53 +0300 Subject: p54spi: compensate firmware alignment bug in p54spi_rx Firmware may insert up to 4 padding bytes after the lmac header, but it does not amend the size of SPI data transfer. Such packets has correct data size in header, thus referencing past the end of allocated skb. Put extra 4 bytes to the end of the received skb to compensate for this case. Signed-off-by: Max Filippov Acked-by: Christian Lamparter Signed-off-by: John W. Linville --- drivers/net/wireless/p54/p54spi.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/p54/p54spi.c b/drivers/net/wireless/p54/p54spi.c index f8af09610180..52023127cf37 100644 --- a/drivers/net/wireless/p54/p54spi.c +++ b/drivers/net/wireless/p54/p54spi.c @@ -395,7 +395,12 @@ static int p54spi_rx(struct p54s_priv *priv) return 0; } - skb = dev_alloc_skb(len); + + /* Firmware may insert up to 4 padding bytes after the lmac header, + * but it does not amend the size of SPI data transfer. + * Such packets has correct data size in header, thus referencing + * past the end of allocated skb. Reserve extra 4 bytes for this case */ + skb = dev_alloc_skb(len + 4); if (!skb) { dev_err(&priv->spi->dev, "could not alloc skb"); return 0; @@ -403,6 +408,9 @@ static int p54spi_rx(struct p54s_priv *priv) p54spi_spi_read(priv, SPI_ADRS_DMA_DATA, skb_put(skb, len), len); p54spi_sleep(priv); + /* Put additional bytes to compensate for the possible + * alignment-caused truncation */ + skb_put(skb, 4); if (p54_rx(priv->hw, skb) == 0) dev_kfree_skb(skb); -- cgit v1.2.3