cfg80211: Fix race in bss timeout
It is quite possible to run into a race in bss timeout where
the drivers see the bss entry just before notifying cfg80211
of a roaming event but it got timed out by the time rdev->event_work
got scehduled from cfg80211_wq. This would result in the following
WARN-ON() along with the failure to notify the user space of
the roaming. The other situation which is happening with ath6kl
that runs into issue is when the driver reports roam to same AP
event where the AP bss entry already got expired. To fix this,
move cfg80211_get_bss() from __cfg80211_roamed() to cfg80211_roamed().
[158645.538384] WARNING: at net/wireless/sme.c:586
__cfg80211_roamed+0xc2/0x1b1()
[158645.538810] Call Trace:
[158645.538838] [<c1033527>] warn_slowpath_common+0x65/0x7a
[158645.538917] [<c14cfacf>] ? __cfg80211_roamed+0xc2/0x1b1
[158645.538946] [<c103354b>] warn_slowpath_null+0xf/0x13
[158645.539055] [<c14cfacf>] __cfg80211_roamed+0xc2/0x1b1
[158645.539086] [<c14beb5b>] cfg80211_process_rdev_events+0x153/0x1cc
[158645.539166] [<c14bd57b>] cfg80211_event_work+0x26/0x36
[158645.539195] [<c10482ae>] process_one_work+0x219/0x38b
[158645.539273] [<c14bd555>] ? wiphy_new+0x419/0x419
[158645.539301] [<c10486cb>] worker_thread+0xf6/0x1bf
[158645.539379] [<c10485d5>] ? rescuer_thread+0x1b5/0x1b5
[158645.539407] [<c104b3e2>] kthread+0x62/0x67
[158645.539484] [<c104b380>] ? __init_kthread_worker+0x42/0x42
[158645.539514] [<c151309a>] kernel_thread_helper+0x6/0xd
Reported-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/core.h b/net/wireless/core.h
index fb08c28..43ad9c8 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -249,12 +249,11 @@
u16 status;
} cr;
struct {
- struct ieee80211_channel *channel;
- u8 bssid[ETH_ALEN];
const u8 *req_ie;
const u8 *resp_ie;
size_t req_ie_len;
size_t resp_ie_len;
+ struct cfg80211_bss *bss;
} rm;
struct {
const u8 *ie;
@@ -403,8 +402,7 @@
struct net_device *dev, u16 reason,
bool wextev);
void __cfg80211_roamed(struct wireless_dev *wdev,
- struct ieee80211_channel *channel,
- const u8 *bssid,
+ struct cfg80211_bss *bss,
const u8 *req_ie, size_t req_ie_len,
const u8 *resp_ie, size_t resp_ie_len);
int cfg80211_mgd_wext_connect(struct cfg80211_registered_device *rdev,