diff options
| author | Ben Greear <greearb@candelatech.com> | 2013-02-20 09:41:09 -0800 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2013-02-26 22:49:05 +0100 |
| commit | 499218595a2e8296b7492af32fcca141b7b8184a (patch) | |
| tree | ee7710d071dd1235c477afc761de3fbf436fc0df | |
| parent | 9b5bd5a4917eeb5eca00d1842a74186cfc8dd1c6 (diff) | |
| download | lwn-499218595a2e8296b7492af32fcca141b7b8184a.tar.gz lwn-499218595a2e8296b7492af32fcca141b7b8184a.zip | |
mac80211: Fix crash due to un-canceled work-items
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:
[<ffffffff81087ef8>] warn_slowpath_common+0x80/0x98
[<ffffffff81087fa4>] warn_slowpath_fmt+0x41/0x43
[<ffffffff812a2608>] debug_print_object+0x7c/0x8d
[<ffffffff812a2bca>] debug_check_no_obj_freed+0x95/0x1c3
[<ffffffff8114cc69>] slab_free_hook+0x70/0x79
[<ffffffff8114ea3e>] kfree+0x62/0xb7
[<ffffffff8149f465>] netdev_release+0x39/0x3e
[<ffffffff8136ad67>] device_release+0x52/0x8a
[<ffffffff812937db>] kobject_release+0x121/0x158
[<ffffffff81293612>] kobject_put+0x4c/0x50
[<ffffffff8148f0d7>] netdev_run_todo+0x25c/0x27e
Cc: stable@vger.kernel.org
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
| -rw-r--r-- | net/mac80211/mlme.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 6044c6d87e4c..b756d2924690 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -4319,6 +4319,17 @@ void ieee80211_mgd_stop(struct ieee80211_sub_if_data *sdata) { 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); |