rt2x00: Fix panic on frame padding for rt2800 usb devices
Backtrace:
rt2800usb_write_tx_data
rt2x00queue_write_tx_frame
rt2x00mac_tx
invoke_tx_handlers
__ieee80211_tx
ieee80211_tx
virt_to_head_page
ieee80211_xmit
ieee80211_tx_skb
ieee80211_scan_work
schedule
ieee80211_scan_work
process_one_work
...
It tried to expand the skb past it's end using skb_put. So I replaced it
with a call to skb_padto, which takes the issue into account.
Signed-off-by: Ismael Luceno <ismael.luceno@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2800usb.c b/drivers/net/wireless/rt2x00/rt2800usb.c
index 3e0205d..b97a4a5 100644
--- a/drivers/net/wireless/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/rt2x00/rt2800usb.c
@@ -369,7 +369,10 @@
static void rt2800usb_write_tx_data(struct queue_entry *entry,
struct txentry_desc *txdesc)
{
- u8 padding_len;
+ unsigned int len;
+ int err;
+
+ rt2800_write_tx_data(entry, txdesc);
/*
* pad(1~3 bytes) is added after each 802.11 payload.
@@ -378,9 +381,14 @@
* | TXINFO | TXWI | 802.11 header | L2 pad | payload | pad | USB end pad |
* |<------------- tx_pkt_len ------------->|
*/
- rt2800_write_tx_data(entry, txdesc);
- padding_len = roundup(entry->skb->len + 4, 4) - entry->skb->len;
- memset(skb_put(entry->skb, padding_len), 0, padding_len);
+ len = roundup(entry->skb->len, 4) + 4;
+ err = skb_padto(entry->skb, len);
+ if (unlikely(err)) {
+ WARNING(entry->queue->rt2x00dev, "TX SKB padding error, out of memory\n");
+ return;
+ }
+
+ entry->skb->len = len;
}
/*
