[PATCH] mac80211 : fix a race with update_tkip_key

gregor kowski
2009-06-07T21:49:01Z

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The mac80211 tkip code won't call update_tkip_key, if some rx packets
get received without KEY_FLAG_UPLOADED_TO_HARDWARE. This can happen on
first packet because the hardware key stuff is called asynchronously with
todo workqueue.

This patch workaround that by always calling update_tkip_key if
the packet wasn't decrypted by the hardware.

Signed-off-by: Gregor Kowski <gregor.kowski@gmail.com>
Index: linux-2.6/net/mac80211/tkip.c
===================================================================
--- linux-2.6.orig/net/mac80211/tkip.c 2009-06-07 19:32:26.000000000 +0000
+++ linux-2.6/net/mac80211/tkip.c 2009-06-07 21:31:31.000000000 +0000
@@ -298,19 +298,19 @@
printk("\n");
}
#endif
- if (key->local->ops->update_tkip_key &&
- key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
- u8 bcast[ETH_ALEN] =
- {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
- u8 *sta_addr = key->sta->sta.addr;
+ }
+ if (key->local->ops->update_tkip_key &&
+ key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
+ u8 bcast[ETH_ALEN] =
+ {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+ u8 *sta_addr = key->sta->sta.addr;

- if (is_multicast_ether_addr(ra))
- sta_addr = bcast;
+ if (is_multicast_ether_addr(ra))
+ sta_addr = bcast;

- key->local->ops->update_tkip_key(
- local_to_hw(key->local), &key->conf,
- sta_addr, iv32, key->u.tkip.rx[queue].p1k);
- }
+ key->local->ops->update_tkip_key(
+ local_to_hw(key->local), &key->conf,
+ sta_addr, iv32, key->u.tkip.rx[queue].p1k);
}

tkip_mixing_phase2(tk, &key->u.tkip.rx[queue], iv16, rc4key);