diff options
| author | Brian Niebuhr <bniebuhr@efjohnson.com> | 2009-08-10 16:46:59 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-09-23 06:46:34 -0700 |
| commit | 9ca33a0f1abdefea3811666d9e87af11fd0af6c6 (patch) | |
| tree | bba1cc2692b38f9a3d76d16910d9575d1d5b0960 /drivers/net/usb | |
| parent | 5429c7316577fcd859f6b53e10884bb8e1e3bcef (diff) | |
USB: Fix CDC EEM host driver 'sentinel' CRC validation
This is an alternate solution to the EEM 'sentinel' CRC valiation issue.
CDC EEM allows using a 'sentinel' ethernet frame CRC of 0xdeadbeef in
place of a real CRC. The 'sentinel' value is transmitted in big-endian
order whereas the normal CRC is little-endian. This patch handles both
cases appropriately.
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/net/usb')
| -rw-r--r-- | drivers/net/usb/cdc_eem.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/net/usb/cdc_eem.c b/drivers/net/usb/cdc_eem.c index 45cebfb302cf..23300656c266 100644 --- a/drivers/net/usb/cdc_eem.c +++ b/drivers/net/usb/cdc_eem.c @@ -300,20 +300,23 @@ static int eem_rx_fixup(struct usbnet *dev, struct sk_buff *skb) return 0; } - crc = get_unaligned_le32(skb2->data - + len - ETH_FCS_LEN); - skb_trim(skb2, len - ETH_FCS_LEN); - /* * The bmCRC helps to denote when the CRC field in * the Ethernet frame contains a calculated CRC: * bmCRC = 1 : CRC is calculated * bmCRC = 0 : CRC = 0xDEADBEEF */ - if (header & BIT(14)) - crc2 = ~crc32_le(~0, skb2->data, skb2->len); - else + if (header & BIT(14)) { + crc = get_unaligned_le32(skb2->data + + len - ETH_FCS_LEN); + crc2 = ~crc32_le(~0, skb2->data, skb2->len + - ETH_FCS_LEN); + } else { + crc = get_unaligned_be32(skb2->data + + len - ETH_FCS_LEN); crc2 = 0xdeadbeef; + } + skb_trim(skb2, len - ETH_FCS_LEN); if (is_last) return crc == crc2; |