cfg80211: fix BSS double-unlinking

commit 3207390a8b upstream.

When multiple interfaces are actively trying
to associate with the same BSS, they may both
find that the BSS isn't there and then try to
unlink it. This can cause errors since the
unlinking code can't currently deal with items
that have already been unlinked.

Normally this doesn't happen as most people
don't try to use multiple station interfaces
that associate at the same time too.

Fix this by using the list entry as a flag to
see if the item is still on a list.

Reported-by: Ben Greear <greearb@candelatech.com>
Tested-by: Hun-Kyi Wynn <hkwynn@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Johannes Berg
2010-10-06 21:18:04 +02:00
committed by Greg Kroah-Hartman
parent f8245147e3
commit 4b99d7de1c

View File

@@ -650,14 +650,14 @@ void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
bss = container_of(pub, struct cfg80211_internal_bss, pub);
spin_lock_bh(&dev->bss_lock);
if (!list_empty(&bss->list)) {
list_del_init(&bss->list);
dev->bss_generation++;
rb_erase(&bss->rbn, &dev->bss_tree);
list_del(&bss->list);
dev->bss_generation++;
rb_erase(&bss->rbn, &dev->bss_tree);
kref_put(&bss->ref, bss_release);
}
spin_unlock_bh(&dev->bss_lock);
kref_put(&bss->ref, bss_release);
}
EXPORT_SYMBOL(cfg80211_unlink_bss);