Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756056Ab3CLWn2 (ORCPT ); Tue, 12 Mar 2013 18:43:28 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60342 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755788Ab3CLWdY (ORCPT ); Tue, 12 Mar 2013 18:33:24 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ben Greear , Johannes Berg Subject: [ 068/100] mac80211: Fix crash due to un-canceled work-items Date: Tue, 12 Mar 2013 15:31:53 -0700 Message-Id: <20130312223130.243283379@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130312223122.884099393@linuxfoundation.org> References: <20130312223122.884099393@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2690 Lines: 73 3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ben Greear commit 499218595a2e8296b7492af32fcca141b7b8184a upstream. Some mlme work structs are not cancelled on disassociation nor interface deletion, which leads to them running after the memory has been freed There is not a clean way to cancel these in the disassociation logic because they must be canceled outside of the ifmgd->mtx lock, so just cancel them in mgd_stop logic that tears down the station. This fixes the crashes we see in 3.7.9+. The crash stack trace itself isn't so helpful, but this warning gives more useful info: WARNING: at /home/greearb/git/linux-3.7.dev.y/lib/debugobjects.c:261 debug_print_object+0x7c/0x8d() ODEBUG: free active (active state 0) object type: work_struct hint: ieee80211_sta_monitor_work+0x0/0x14 [mac80211] Modules linked in: [...] Pid: 14743, comm: iw Tainted: G C O 3.7.9+ #11 Call Trace: [] warn_slowpath_common+0x80/0x98 [] warn_slowpath_fmt+0x41/0x43 [] debug_print_object+0x7c/0x8d [] debug_check_no_obj_freed+0x95/0x1c3 [] slab_free_hook+0x70/0x79 [] kfree+0x62/0xb7 [] netdev_release+0x39/0x3e [] device_release+0x52/0x8a [] kobject_release+0x121/0x158 [] kobject_put+0x4c/0x50 [] netdev_run_todo+0x25c/0x27e Signed-off-by: Ben Greear Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/mac80211/mlme.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -4072,6 +4072,17 @@ void ieee80211_mgd_stop(struct ieee80211 { struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; + /* + * Make sure some work items will not run after this, + * they will not do anything but might not have been + * cancelled when disconnecting. + */ + cancel_work_sync(&ifmgd->monitor_work); + cancel_work_sync(&ifmgd->beacon_connection_loss_work); + cancel_work_sync(&ifmgd->request_smps_work); + cancel_work_sync(&ifmgd->csa_connection_drop_work); + cancel_work_sync(&ifmgd->chswitch_work); + mutex_lock(&ifmgd->mtx); if (ifmgd->assoc_data) ieee80211_destroy_assoc_data(sdata, false); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/