[PATCH 5.12 153/178] mac80211: fix reset debugfs locking

Greg Kroah-Hartman
2021-06-21T16:50:21Z

From: Johannes Berg <johannes.berg@intel.com>

commit adaed1b9daf5a045be71e923e04b5069d2bee664 upstream.

cfg80211 now calls suspend/resume with the wiphy lock
held, and while there's a problem with that needing
to be fixed, we should do the same in debugfs.

Cc: stable@vger.kernel.org
Fixes: a05829a7222e ("cfg80211: avoid holding the RTNL when calling the driver")
Link: https://lore.kernel.org/r/20210608113226.14020430e449.I78e19db0a55a8295a376e15ac4cf77dbb4c6fb51@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/mac80211/debugfs.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -4,7 +4,7 @@
*
* Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
* Copyright 2013-2014 Intel Mobile Communications GmbH
- * Copyright (C) 2018 - 2019 Intel Corporation
+ * Copyright (C) 2018 - 2019, 2021 Intel Corporation
*/

#include <linux/debugfs.h>
@@ -389,8 +389,10 @@ static ssize_t reset_write(struct file *
struct ieee80211_local *local = file->private_data;

rtnl_lock();
+ wiphy_lock(local->hw.wiphy);
__ieee80211_suspend(&local->hw, NULL);
__ieee80211_resume(&local->hw);
+ wiphy_unlock(local->hw.wiphy);
rtnl_unlock();

return count;