diff options
| -rw-r--r-- | package/mac80211/patches/100-cfg80211_fix_scan_check_again.patch | 98 | 
1 files changed, 98 insertions, 0 deletions
diff --git a/package/mac80211/patches/100-cfg80211_fix_scan_check_again.patch b/package/mac80211/patches/100-cfg80211_fix_scan_check_again.patch new file mode 100644 index 000000000..77b795c12 --- /dev/null +++ b/package/mac80211/patches/100-cfg80211_fix_scan_check_again.patch @@ -0,0 +1,98 @@ +Subject: cfg80211: check lost scans later, fix bug + +When we lose a scan, cfg80211 tries to clean up after +the driver. However, it currently does this too early, +it does this in GOING_DOWN already instead of DOWN, so +it may happen with mac80211. Besides fixing this, also +make it more robust by leaking the scan request so if +the driver later actually finishes the scan, it won't +crash. Also check in ___cfg80211_scan_done whether a +scan request is still pending and exit if not. + +Signed-off-by: Johannes Berg <johannes@sipsolutions.net> +--- + net/wireless/core.c |    4 +++- + net/wireless/core.h |    2 +- + net/wireless/scan.c |   19 ++++++++++++++++--- + 3 files changed, 20 insertions(+), 5 deletions(-) + +--- a/net/wireless/core.c ++++ b/net/wireless/core.c +@@ -664,7 +664,7 @@ static void wdev_cleanup_work(struct wor +  + 	if (WARN_ON(rdev->scan_req && rdev->scan_req->dev == wdev->netdev)) { + 		rdev->scan_req->aborted = true; +-		___cfg80211_scan_done(rdev); ++		___cfg80211_scan_done(rdev, true); + 	} +  + 	cfg80211_unlock_rdev(rdev); +@@ -755,6 +755,8 @@ static int cfg80211_netdev_notifier_call + 		default: + 			break; + 		} ++		break; ++	case NETDEV_DOWN: + 		dev_hold(dev); + 		schedule_work(&wdev->cleanup_work); + 		break; +--- a/net/wireless/core.h ++++ b/net/wireless/core.h +@@ -374,7 +374,7 @@ void cfg80211_sme_scan_done(struct net_d + void cfg80211_sme_rx_auth(struct net_device *dev, const u8 *buf, size_t len); + void cfg80211_sme_disassoc(struct net_device *dev, int idx); + void __cfg80211_scan_done(struct work_struct *wk); +-void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev); ++void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak); + void cfg80211_upload_connect_keys(struct wireless_dev *wdev); +  + struct ieee80211_channel * +--- a/net/wireless/scan.c ++++ b/net/wireless/scan.c +@@ -18,7 +18,7 @@ +  + #define IEEE80211_SCAN_RESULT_EXPIRE	(15 * HZ) +  +-void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev) ++void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak) + { + 	struct cfg80211_scan_request *request; + 	struct net_device *dev; +@@ -28,6 +28,9 @@ void ___cfg80211_scan_done(struct cfg802 +  + 	request = rdev->scan_req; +  ++	if (!request) ++		return; ++ + 	dev = request->dev; +  + 	/* +@@ -53,7 +56,17 @@ void ___cfg80211_scan_done(struct cfg802 + 	dev_put(dev); +  + 	rdev->scan_req = NULL; +-	kfree(request); ++ ++	/* ++	 * OK. If this is invoked with "leak" then we can't ++	 * free this ... but we've cleaned it up anyway. The ++	 * driver failed to call the scan_done callback, so ++	 * all bets are off, it might still be trying to use ++	 * the scan request or not ... if it accesses the dev ++	 * in there (it shouldn't anyway) then it may crash. ++	 */ ++	if (!leak) ++		kfree(request); + } +  + void __cfg80211_scan_done(struct work_struct *wk) +@@ -64,7 +77,7 @@ void __cfg80211_scan_done(struct work_st + 			    scan_done_wk); +  + 	cfg80211_lock_rdev(rdev); +-	___cfg80211_scan_done(rdev); ++	___cfg80211_scan_done(rdev, false); + 	cfg80211_unlock_rdev(rdev); + } +   | 
