diff options
| author | Johannes Berg <johannes@sipsolutions.net> | 2007-09-26 15:19:47 +0200 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2007-10-10 16:53:16 -0700 |
| commit | 53918994b7c8c3bf0af5f641e1f299856799d883 (patch) | |
| tree | 63338872613d3c08473acfb46c8a57490f85350b /net/mac80211/rx.c | |
| parent | 50741ae05a4742cae99361f57d84b5f8d33822a4 (diff) | |
| download | linux-53918994b7c8c3bf0af5f641e1f299856799d883.tar.bz2 | |
[PATCH] mac80211: fix iff_promiscs, iff_allmultis race
When we update the counters iff_promiscs and iff_allmultis
in struct ieee80211_local we have no common lock held to
protect them. The problem is that the update to each counter
may not be atomic, so we could end up with iff_promiscs == -1
in unfortunate conditions. To fix it, use atomic_t values.
It doesn't matter whether the two counters are updated
together atomically or not, if there are two invocations
of set_multicast_list we will end up with multiple
configure_filter() invocations of which the latter will always
be correct.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net/mac80211/rx.c')
| -rw-r--r-- | net/mac80211/rx.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 34adc5288fbc..03635fb3e9b6 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1531,7 +1531,8 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, skb = rx.skb; if (sta && !(sta->flags & (WLAN_STA_WDS | WLAN_STA_ASSOC_AP)) && - !local->iff_promiscs && !is_multicast_ether_addr(hdr->addr1)) { + !atomic_read(&local->iff_promiscs) && + !is_multicast_ether_addr(hdr->addr1)) { rx.flags |= IEEE80211_TXRXD_RXRA_MATCH; ieee80211_invoke_rx_handlers(local, local->rx_handlers, &rx, rx.sta); |