diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2011-09-22 14:59:04 -0700 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2011-09-26 14:55:50 -0400 |
| commit | 6c80c39d9a6986a566c30d797aae37bfb697eea3 (patch) | |
| tree | 8ce4d0e71e4daacf3724ab15a8265f1a53926325 | |
| parent | 1b9ca0272ffae212e726380f66777b30a56ed7a5 (diff) | |
| download | linux-6c80c39d9a6986a566c30d797aae37bfb697eea3.tar.bz2 | |
iwlagn: fix dangling scan request
If iwl_scan_initiate() fails for any reason,
priv->scan_request and priv->scan_vif are left
dangling. This can lead to a crash later when
iwl_bg_scan_completed() tries to run a pending
scan request.
In practice, this seems to be very rare due to
the STATUS_SCANNING check earlier. That check,
however, is wrong -- it should allow a scan to
be queued when a reset/roc scan is going on.
When a normal scan is already going on, a new
one can't be issued by mac80211, so that code
can be removed completely. I introduced this
bug when adding off-channel support in commit
266af4c745952e9bebf687dd68af58df553cb59d.
Cc: stable@kernel.org [3.0]
Reported-by: Peng Yan <peng.yan@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-scan.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c index dd6937e97055..77e528f5db88 100644 --- a/drivers/net/wireless/iwlwifi/iwl-scan.c +++ b/drivers/net/wireless/iwlwifi/iwl-scan.c @@ -405,31 +405,33 @@ int iwl_mac_hw_scan(struct ieee80211_hw *hw, mutex_lock(&priv->mutex); - if (test_bit(STATUS_SCANNING, &priv->status) && - priv->scan_type != IWL_SCAN_NORMAL) { - IWL_DEBUG_SCAN(priv, "Scan already in progress.\n"); - ret = -EAGAIN; - goto out_unlock; - } - - /* mac80211 will only ask for one band at a time */ - priv->scan_request = req; - priv->scan_vif = vif; - /* * If an internal scan is in progress, just set * up the scan_request as per above. */ if (priv->scan_type != IWL_SCAN_NORMAL) { - IWL_DEBUG_SCAN(priv, "SCAN request during internal scan\n"); + IWL_DEBUG_SCAN(priv, + "SCAN request during internal scan - defer\n"); + priv->scan_request = req; + priv->scan_vif = vif; ret = 0; - } else + } else { + priv->scan_request = req; + priv->scan_vif = vif; + /* + * mac80211 will only ask for one band at a time + * so using channels[0] here is ok + */ ret = iwl_scan_initiate(priv, vif, IWL_SCAN_NORMAL, req->channels[0]->band); + if (ret) { + priv->scan_request = NULL; + priv->scan_vif = NULL; + } + } IWL_DEBUG_MAC80211(priv, "leave\n"); -out_unlock: mutex_unlock(&priv->mutex); return ret; |