[067/151] mac80211: fix scan abort sanity checks

Greg KH
2009-12-17T04:05:25Z

From: Johannes Berg <johannes@sipsolutions.net>

commit 6d3560d4fc9c5b9fe1a07a63926ea70512c69c32 upstream.

Since sometimes mac80211 queues up a scan request
to only act on it later, it must be allowed to
(internally) cancel a not-yet-running scan, e.g.
when the interface is taken down. This condition
was missing since we always checked only the
local->scanning variable which isn't yet set in
that situation.

Reported-by: Luis R. Rodriguez <mcgrof@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
net/mac80211/scan.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -264,10 +264,14 @@ void ieee80211_scan_completed(struct iee

mutex_lock(&local->scan_mtx);

- if (WARN_ON(!local->scanning)) {
- mutex_unlock(&local->scan_mtx);
- return;
- }
+ /*
+ * It's ok to abort a not-yet-running scan (that
+ * we have one at all will be verified by checking
+ * local->scan_req next), but not to complete it
+ * successfully.
+ */
+ if (WARN_ON(!local->scanning && !aborted))
+ aborted = true;

if (WARN_ON(!local->scan_req)) {
mutex_unlock(&local->scan_mtx);