mac80211: call drv_stop only if driver is started

If drv_start() fails during hw_restart, all the running
interfaces are being closed/stopped, which results in
drv_stop() being called, although the driver was never
started successfully.

This might cause drivers to perform operations on uninitialized
memory (as they assume it was initialized on drv_start)

Consider the local->started flag, and call the driver's stop()
op only if drv_start() succeeded before.

Move drv_start() and drv_stop() to driver-ops.c, as they are no
longer simple wrappers.

Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Eliad Peller 2015-10-25 10:59:36 +02:00 committed by Johannes Berg
parent c189a685b8
commit 968a76cef3
3 changed files with 48 additions and 31 deletions

View file

@ -1,4 +1,6 @@
/*
* Copyright 2015 Intel Deutschland GmbH
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
@ -8,6 +10,48 @@
#include "trace.h"
#include "driver-ops.h"
int drv_start(struct ieee80211_local *local)
{
int ret;
might_sleep();
if (WARN_ON(local->started))
return -EALREADY;
trace_drv_start(local);
local->started = true;
/* allow rx frames */
smp_mb();
ret = local->ops->start(&local->hw);
trace_drv_return_int(local, ret);
if (ret)
local->started = false;
return ret;
}
void drv_stop(struct ieee80211_local *local)
{
might_sleep();
if (WARN_ON(!local->started))
return;
trace_drv_stop(local);
local->ops->stop(&local->hw);
trace_drv_return_void(local);
/* sync away all work on the tasklet before clearing started */
tasklet_disable(&local->tasklet);
tasklet_enable(&local->tasklet);
barrier();
local->started = false;
}
int drv_add_interface(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata)
{

View file

@ -66,36 +66,8 @@ static inline int drv_get_et_sset_count(struct ieee80211_sub_if_data *sdata,
return rv;
}
static inline int drv_start(struct ieee80211_local *local)
{
int ret;
might_sleep();
trace_drv_start(local);
local->started = true;
smp_mb();
ret = local->ops->start(&local->hw);
trace_drv_return_int(local, ret);
return ret;
}
static inline void drv_stop(struct ieee80211_local *local)
{
might_sleep();
trace_drv_stop(local);
local->ops->stop(&local->hw);
trace_drv_return_void(local);
/* sync away all work on the tasklet before clearing started */
tasklet_disable(&local->tasklet);
tasklet_enable(&local->tasklet);
barrier();
local->started = false;
}
int drv_start(struct ieee80211_local *local);
void drv_stop(struct ieee80211_local *local);
#ifdef CONFIG_PM
static inline int drv_suspend(struct ieee80211_local *local,

View file

@ -1665,7 +1665,6 @@ static void ieee80211_handle_reconfig_failure(struct ieee80211_local *local)
local->resuming = false;
local->suspended = false;
local->started = false;
local->in_reconfig = false;
/* scheduled scan clearly can't be running any more, but tell
@ -1764,6 +1763,8 @@ int ieee80211_reconfig(struct ieee80211_local *local)
if (suspended && local->in_reconfig && !reconfig_due_to_wowlan)
cancel_work_sync(&local->restart_work);
local->started = false;
/*
* Upon resume hardware can sometimes be goofy due to
* various platform / driver / bus issues, so restarting