From 968a76cef3d1bb9a3b4d135cd788056e742859f3 Mon Sep 17 00:00:00 2001 From: Eliad Peller Date: Sun, 25 Oct 2015 10:59:36 +0200 Subject: 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 Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/mac80211/driver-ops.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'net/mac80211/driver-ops.c') diff --git a/net/mac80211/driver-ops.c b/net/mac80211/driver-ops.c index a1d54318f16c..9f97343f13fd 100644 --- a/net/mac80211/driver-ops.c +++ b/net/mac80211/driver-ops.c @@ -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) { -- cgit