mac80211: fix paged defragmentation

Paged RX skb patch broke the defragmentation. We need to read hdr again
after linearization.

It fixes following bug
http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=2194

Signed-off-by: Zhu, Yi <yi.zhu@intel.com>
Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index e4f325f68fd3..8fa99554f4e2 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1252,6 +1252,12 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
         if (skb_linearize(rx->skb))
                 return RX_DROP_UNUSABLE;
 
+        /*
+         *  skb_linearize() might change the skb->data and
+         *  previously cached variables (in this case, hdr) need to
+         *  be refreshed with the new data.
+         */
+        hdr = (struct ieee80211_hdr *)rx->skb->data;
         seq = (sc & IEEE80211_SCTL_SEQ) >> 4;
 
         if (frag == 0) {