[PATCH 3.10 080/173] mwifiex: fix wrong eth_hdr usage for bridged packets in AP mode

Greg Kroah-Hartman
2013-12-02T19:11:03Z

From: Ujjal Roy <royujjal@gmail.com>

commit 8d93f1f309d38b65fce0b9f0de91ba6c96990c07 upstream.

The eth_hdr is never defined in this driver but it gets compiled
without any warning/error because kernel has defined eth_hdr.

Fix it by defining our own p_ethhdr and use it instead of eth_hdr.

Signed-off-by: Ujjal Roy <royujjal@gmail.com>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/wireless/mwifiex/uap_txrx.c | 29 ++++++++++++++++++++++++++---
1 file changed, 26 insertions(+), 3 deletions(-)

--- a/drivers/net/wireless/mwifiex/uap_txrx.c
+++ b/drivers/net/wireless/mwifiex/uap_txrx.c
@@ -34,6 +34,7 @@ static void mwifiex_uap_queue_bridged_pk
struct mwifiex_txinfo *tx_info;
int hdr_chop;
struct timeval tv;
+ struct ethhdr *p_ethhdr;
u8 rfc1042_eth_hdr[ETH_ALEN] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };

uap_rx_pd = (struct uap_rxpd *)(skb->data);
@@ -48,14 +49,36 @@ static void mwifiex_uap_queue_bridged_pk
}

if (!memcmp(&rx_pkt_hdr->rfc1042_hdr,
- rfc1042_eth_hdr, sizeof(rfc1042_eth_hdr)))
+ rfc1042_eth_hdr, sizeof(rfc1042_eth_hdr))) {
+ /* Replace the 803 header and rfc1042 header (llc/snap) with
+ * an Ethernet II header, keep the src/dst and snap_type
+ * (ethertype).
+ *
+ * The firmware only passes up SNAP frames converting all RX
+ * data from 802.11 to 802.2/LLC/SNAP frames.
+ *
+ * To create the Ethernet II, just move the src, dst address
+ * right before the snap_type.
+ */
+ p_ethhdr = (struct ethhdr *)
+ ((u8 *)(&rx_pkt_hdr->eth803_hdr)
+ + sizeof(rx_pkt_hdr->eth803_hdr)
+ + sizeof(rx_pkt_hdr->rfc1042_hdr)
+ - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
+ - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
+ - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));
+ memcpy(p_ethhdr->h_source, rx_pkt_hdr->eth803_hdr.h_source,
+ sizeof(p_ethhdr->h_source));
+ memcpy(p_ethhdr->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
+ sizeof(p_ethhdr->h_dest));
/* Chop off the rxpd + the excess memory from
* 802.2/llc/snap header that was removed.
*/
- hdr_chop = (u8 *)eth_hdr - (u8 *)uap_rx_pd;
- else
+ hdr_chop = (u8 *)p_ethhdr - (u8 *)uap_rx_pd;
+ } else {
/* Chop off the rxpd */
hdr_chop = (u8 *)&rx_pkt_hdr->eth803_hdr - (u8 *)uap_rx_pd;
+ }

/* Chop off the leading header bytes so the it points
* to the start of either the reconstructed EthII frame