mac80211_hwsim: call ieee80211_tx_prepare_skb under RCU protection

[ Upstream commit 9e2db50f1ef2238fc2f71c5de1c0418b7a5b0ea2 ]

This is needed since it might use (and pass out) pointers to
e.g. keys protected by RCU. Can't really happen here as the
frames aren't encrypted, but we need to still adhere to the
rules.

Fixes: cacfddf82baf ("mac80211_hwsim: initialize ieee80211_tx_info at hw_scan_work")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20220505230421.5f139f9de173.I77ae111a28f7c0e9fd1ebcee7f39dbec5c606770@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index c84ee5ba53812907d571d41407ca917e0577231c..3d8e17bb8a101203f8aeac8061ba38e37a9b7ce7 100644 (file)
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -2082,11 +2082,13 @@ static void hw_scan_work(struct work_struct *work)
                        if (req->ie_len)
                                skb_put_data(probe, req->ie, req->ie_len);
 
+                       rcu_read_lock();
                        if (!ieee80211_tx_prepare_skb(hwsim->hw,
                                                      hwsim->hw_scan_vif,
                                                      probe,
                                                      hwsim->tmp_chan->band,
                                                      NULL)) {
+                               rcu_read_unlock();
                                kfree_skb(probe);
                                continue;
                        }
@@ -2094,6 +2096,7 @@ static void hw_scan_work(struct work_struct *work)
                        local_bh_disable();
                        mac80211_hwsim_tx_frame(hwsim->hw, probe,
                                                hwsim->tmp_chan);
+                       rcu_read_unlock();
                        local_bh_enable();
                }
        }