From 4a484cffc5e1836114e9556f7c704412d491200c Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 9 Jan 2013 10:22:07 +0100 Subject: [PATCH] regulatory: fix uevent The uevent callback doesn't protect its access to last_request, which now causes a warning since the conversion to get_last_request(). Fix this by allowing to use RCU protection for last_request. Reported-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/wireless/reg.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 0b35de001937..2193f62bb8ae 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -140,8 +140,8 @@ static void rcu_free_regdom(const struct ieee80211_regdomain *r) static struct regulatory_request *get_last_request(void) { - return rcu_dereference_protected(last_request, - lockdep_is_held(®_mutex)); + return rcu_dereference_check(last_request, + lockdep_is_held(®_mutex)); } /* Used to queue up regulatory hints */ @@ -2250,14 +2250,21 @@ int set_regdom(const struct ieee80211_regdomain *rd) #ifdef CONFIG_HOTPLUG int reg_device_uevent(struct device *dev, struct kobj_uevent_env *env) { - struct regulatory_request *lr = get_last_request(); + struct regulatory_request *lr; + u8 alpha2[2]; + bool add = false; + rcu_read_lock(); + lr = get_last_request(); if (lr && !lr->processed) { - if (add_uevent_var(env, "COUNTRY=%c%c", - lr->alpha2[0], lr->alpha2[1])) - return -ENOMEM; + memcpy(alpha2, lr->alpha2, 2); + add = true; } + rcu_read_unlock(); + if (add) + return add_uevent_var(env, "COUNTRY=%c%c", + alpha2[0], alpha2[1]); return 0; } #else -- 2.34.1