Re: Warning emited by 2.6.24-rc6-git5

[Ivo van Doorn <ivdoorn@gmail.com>]

On Wednesday 02 January 2008, Chris Clayton wrote:
> On Monday 31 December 2007, Ivo Van Doorn wrote:
> > On Dec 31, 2007 8:27 AM, Kalle Valo <kalle.valo@nokia.com> wrote:
> > > Ivo van Doorn <ivdoorn@gmail.com> writes:
> > > > +             /*
> > > > +              * Move entire frame 2 bytes to the front.
> > > > +              */
> > > > +             skb_push(skb, 2);
> > > > +             memmove(skb->data, skb->data + 2, skb->len - 2);
> > >
> > > No skb_trim()? Shoudn't there be skb_trim(skb, 2) after memmove()?
> >
> > Good point, I completely forgot about that. :S
> > Thanks. :)
> >
> > Ivo
> 
> Ah, does the patch I have applied and am running need enhancement, please?

---

diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index ff399f8..3c10a68 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -386,6 +386,7 @@ void rt2x00lib_rxdone(struct data_entry *entry, struct sk_buff *skb,
 	struct ieee80211_rx_status *rx_status = &rt2x00dev->rx_status;
 	struct ieee80211_hw_mode *mode;
 	struct ieee80211_rate *rate;
+	unsigned int header_size;
 	unsigned int i;
 	int val = 0;
 
@@ -412,6 +413,27 @@ void rt2x00lib_rxdone(struct data_entry *entry, struct sk_buff *skb,
 		}
 	}
 
+	/*
+	 * Properly align the ieee80211 frame and make sure the
+	 * data behind the ieee80211 header is on a 4 byte boundrary.
+	 */
+	header_size = ieee80211_get_hdrlen_from_skb(skb);
+	if (!header_size) {
+		/*
+		 * Frame is too short to contain a valid header,
+		 * drop the entire frame since it is useless.
+		 */
+		kfree_skb(skb);
+		return;
+	} else if (header_size % 4 == 0) {
+		/*
+		 * Move entire frame 2 bytes to the front.
+		 */
+		skb_push(skb, 2);
+		memmove(skb->data, skb->data + 2, skb->len - 2);
+		skb_trim(skb, skb->len - 2);
+	}
+
 	rt2x00_update_link_rssi(&rt2x00dev->link, desc->rssi);
 	rt2x00dev->link.rx_success++;
 	rx_status->rate = val;