[PATCH] net: mac80211: rx.c: Avoid RCU list traversal under mutex

From: madhuparnabhowmik10
Date: Sun Feb 23 2020 - 09:33:44 EST


From: Madhuparna Bhowmik <madhuparnabhowmik10@xxxxxxxxx>

local->sta_mtx is held in __ieee80211_check_fast_rx_iface().
No need to use list_for_each_entry_rcu() as it also requires
a cond argument to avoid false lockdep warnings when not used in
RCU read-side section (with CONFIG_PROVE_RCU_LIST).
Therefore use list_for_each_entry();

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@xxxxxxxxx>
---
net/mac80211/rx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 0e05ff037672..0ba98ad9bc85 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -4114,7 +4114,7 @@ void __ieee80211_check_fast_rx_iface(struct ieee80211_sub_if_data *sdata)

lockdep_assert_held(&local->sta_mtx);

- list_for_each_entry_rcu(sta, &local->sta_list, list) {
+ list_for_each_entry(sta, &local->sta_list, list) {
if (sdata != sta->sdata &&
(!sta->sdata->bss || sta->sdata->bss != sdata->bss))
continue;
--
2.17.1