On Wed, 2011-02-16 at 10:54 +0100, Stanislaw Gruszka wrote: > Low level driver could pass rx frames to us after disassociate, what > can lead to run conn_mon_timer by ieee80211_sta_rx_notify(). Thats > is obviously wrong, but nothing happens until we unload modules and > resources are used after free. If kernel debugging is enabled following > warning could be observed: > > WARNING: at lib/debugobjects.c:259 debug_print_object+0x65/0x70() > Hardware name: HP xw8600 Workstation > ODEBUG: free active (active state 0) object type: timer_list > Modules linked in: iwlagn(-) iwlcore mac80211 cfg80211 ... > Pid: 13827, comm: rmmod Tainted: G W 2.6.38-rc4-wl+ #22 > Call Trace: > [<ffffffff810649cf>] ? warn_slowpath_common+0x7f/0xc0 > [<ffffffff81064ac6>] ? warn_slowpath_fmt+0x46/0x50 > [<ffffffff81226fc5>] ? debug_print_object+0x65/0x70 > [<ffffffff81227625>] ? debug_check_no_obj_freed+0x125/0x210 > [<ffffffff8109ebd7>] ? debug_check_no_locks_freed+0xf7/0x170 > [<ffffffff81156092>] ? kfree+0xc2/0x2f0 > [<ffffffff813ec5c5>] ? netdev_release+0x45/0x60 > [<ffffffff812f1067>] ? device_release+0x27/0xa0 > [<ffffffff81216ddd>] ? kobject_release+0x8d/0x1a0 > [<ffffffff81216d50>] ? kobject_release+0x0/0x1a0 > [<ffffffff812183b7>] ? kref_put+0x37/0x70 > [<ffffffff81216c57>] ? kobject_put+0x27/0x60 > [<ffffffff813d5d1b>] ? netdev_run_todo+0x1ab/0x270 > [<ffffffff813e771e>] ? rtnl_unlock+0xe/0x10 > [<ffffffffa0581188>] ? ieee80211_unregister_hw+0x58/0x120 [mac80211] > [<ffffffffa0377ed7>] ? iwl_pci_remove+0xdb/0x22a [iwlagn] > [<ffffffff8123cde2>] ? pci_device_remove+0x52/0x120 > [<ffffffff812f5205>] ? __device_release_driver+0x75/0xe0 > [<ffffffff812f5348>] ? driver_detach+0xd8/0xe0 > [<ffffffff812f4111>] ? bus_remove_driver+0x91/0x100 > [<ffffffff812f5b62>] ? driver_unregister+0x62/0xa0 > [<ffffffff8123d194>] ? pci_unregister_driver+0x44/0xa0 > [<ffffffffa0377df5>] ? iwl_exit+0x15/0x1c [iwlagn] > [<ffffffff810ab492>] ? sys_delete_module+0x1a2/0x270 > [<ffffffff81498889>] ? trace_hardirqs_on_thunk+0x3a/0x3f > [<ffffffff8100bf42>] ? system_call_fastpath+0x16/0x1b > > Signed-off-by: Stanislaw Gruszka <sgruszka@xxxxxxxxxx> > --- > net/mac80211/mlme.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c > index d89e878..7b3f9df 100644 > --- a/net/mac80211/mlme.c > +++ b/net/mac80211/mlme.c > @@ -1071,6 +1071,12 @@ void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata, > if (is_multicast_ether_addr(hdr->addr1)) > return; > > + /* > + * In case we receive pending frames after disassociation. > + */ > + if (!sdata->u.mgd.associated) > + return; > + > ieee80211_sta_reset_conn_monitor(sdata); > } > good catch, thanks. johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
