diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2012-12-06 15:47:38 +0100 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2013-01-03 13:01:29 +0100 |
| commit | 458f4f9e960b9a3b674c4b87d996eef186b1fe83 (patch) | |
| tree | febf655badc2a045b3aaaf63271226729c76e325 /net/wireless/nl80211.c | |
| parent | 379b82f4c9dc6e67bf61aa61b096c06a2f320f60 (diff) | |
regulatory: use RCU to protect global and wiphy regdomains
To simplify the locking and not require cfg80211_mutex
(which nl80211 uses to access the global regdomain) and
also to make it possible for drivers to access their
wiphy->regd safely, use RCU to protect these pointers.
Acked-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/wireless/nl80211.c')
| -rw-r--r-- | net/wireless/nl80211.c | 35 |
1 files changed, 18 insertions, 17 deletions
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index b387deaf1132..b3cf7cc0d4a1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3787,12 +3787,8 @@ static int nl80211_req_set_reg(struct sk_buff *skb, struct genl_info *info) * window between nl80211_init() and regulatory_init(), if that is * even possible. */ - mutex_lock(&cfg80211_mutex); - if (unlikely(!cfg80211_regdomain)) { - mutex_unlock(&cfg80211_mutex); + if (unlikely(!rcu_access_pointer(cfg80211_regdomain))) return -EINPROGRESS; - } - mutex_unlock(&cfg80211_mutex); if (!info->attrs[NL80211_ATTR_REG_ALPHA2]) return -EINVAL; @@ -4152,6 +4148,7 @@ static int nl80211_update_mesh_config(struct sk_buff *skb, static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info) { + const struct ieee80211_regdomain *regdom; struct sk_buff *msg; void *hdr = NULL; struct nlattr *nl_reg_rules; @@ -4174,35 +4171,36 @@ static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info) if (!hdr) goto put_failure; - if (nla_put_string(msg, NL80211_ATTR_REG_ALPHA2, - cfg80211_regdomain->alpha2) || - (cfg80211_regdomain->dfs_region && - nla_put_u8(msg, NL80211_ATTR_DFS_REGION, - cfg80211_regdomain->dfs_region))) - goto nla_put_failure; - if (reg_last_request_cell_base() && nla_put_u32(msg, NL80211_ATTR_USER_REG_HINT_TYPE, NL80211_USER_REG_HINT_CELL_BASE)) goto nla_put_failure; + rcu_read_lock(); + regdom = rcu_dereference(cfg80211_regdomain); + + if (nla_put_string(msg, NL80211_ATTR_REG_ALPHA2, regdom->alpha2) || + (regdom->dfs_region && + nla_put_u8(msg, NL80211_ATTR_DFS_REGION, regdom->dfs_region))) + goto nla_put_failure_rcu; + nl_reg_rules = nla_nest_start(msg, NL80211_ATTR_REG_RULES); if (!nl_reg_rules) - goto nla_put_failure; + goto nla_put_failure_rcu; - for (i = 0; i < cfg80211_regdomain->n_reg_rules; i++) { + for (i = 0; i < regdom->n_reg_rules; i++) { struct nlattr *nl_reg_rule; const struct ieee80211_reg_rule *reg_rule; const struct ieee80211_freq_range *freq_range; const struct ieee80211_power_rule *power_rule; - reg_rule = &cfg80211_regdomain->reg_rules[i]; + reg_rule = ®dom->reg_rules[i]; freq_range = ®_rule->freq_range; power_rule = ®_rule->power_rule; nl_reg_rule = nla_nest_start(msg, i); if (!nl_reg_rule) - goto nla_put_failure; + goto nla_put_failure_rcu; if (nla_put_u32(msg, NL80211_ATTR_REG_RULE_FLAGS, reg_rule->flags) || @@ -4216,10 +4214,11 @@ static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info) power_rule->max_antenna_gain) || nla_put_u32(msg, NL80211_ATTR_POWER_RULE_MAX_EIRP, power_rule->max_eirp)) - goto nla_put_failure; + goto nla_put_failure_rcu; nla_nest_end(msg, nl_reg_rule); } + rcu_read_unlock(); nla_nest_end(msg, nl_reg_rules); @@ -4227,6 +4226,8 @@ static int nl80211_get_reg(struct sk_buff *skb, struct genl_info *info) err = genlmsg_reply(msg, info); goto out; +nla_put_failure_rcu: + rcu_read_unlock(); nla_put_failure: genlmsg_cancel(msg, hdr); put_failure: |