From: Johannes Berg <johannes.berg@xxxxxxxxx>
If the regulatory database is loaded, and then updated, it may
be necessary to reload it. Add an nl80211 command to do this,
and RCU-ify the pointer to the regdb "firmware" to allow it to
be replaced at runtime.
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
---
include/uapi/linux/nl80211.h | 4 +++
net/wireless/nl80211.c | 11 ++++++
net/wireless/reg.c | 84 ++++++++++++++++++++++++++++++++++++--------
net/wireless/reg.h | 6 ++++
4 files changed, 90 insertions(+), 15 deletions(-)
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 51626b4175c0..926eb92cb4a8 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -983,6 +983,8 @@
* configured PMK for the authenticator address identified by
* &NL80211_ATTR_MAC.
*
+ * @NL80211_CMD_RELOAD_REGDB: Request that the regdb firmware file is reloaded.
+ *
* @NL80211_CMD_MAX: highest used command number
* @__NL80211_CMD_AFTER_LAST: internal use
*/
@@ -1185,6 +1187,8 @@ enum nl80211_commands {
NL80211_CMD_SET_PMK,
NL80211_CMD_DEL_PMK,
+ NL80211_CMD_RELOAD_REGDB,
+
/* add new commands above here */
/* used to define NL80211_CMD_MAX below */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 8ce85420ecb0..ee902ea13833 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5669,6 +5669,11 @@ static int nl80211_req_set_reg(struct sk_buff *skb, struct genl_info *info)
}
}
+static int nl80211_reload_regdb(struct sk_buff *skb, struct genl_info *info)
+{
+ return reg_reload_regdb();
+}
+
static int nl80211_get_mesh_config(struct sk_buff *skb,
struct genl_info *info)
{
@@ -12668,6 +12673,12 @@ static const struct genl_ops nl80211_ops[] = {
.policy = nl80211_policy,
.flags = GENL_ADMIN_PERM,
},
+ {
+ .cmd = NL80211_CMD_RELOAD_REGDB,
+ .doit = nl80211_reload_regdb,
+ .policy = nl80211_policy,
+ .flags = GENL_ADMIN_PERM,
+ },
{
.cmd = NL80211_CMD_GET_MESH_CONFIG,
.doit = nl80211_get_mesh_config,
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 7a1d6cda64f3..8d366738c08a 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -602,7 +602,7 @@ static inline int call_crda(const char *alpha2)
#endif /* CONFIG_CFG80211_CRDA_SUPPORT */
/* code to directly load a firmware database through request_firmware */
-static const struct firmware *regdb;
+static const struct firmware __rcu *regdb;
static unsigned int fwregdb_attempts = 10;
struct fwdb_country {
@@ -756,47 +756,76 @@ static int query_regdb(const char *alpha2)
{
const struct fwdb_header *hdr;
const struct fwdb_country *country;
+ const struct firmware *db;
+ int err;
- if (IS_ERR(regdb))
- return PTR_ERR(regdb);
+ rcu_read_lock();
+ db = rcu_dereference(regdb);
- hdr = (void *)regdb->data;
+ if (IS_ERR(db)) {
+ err = PTR_ERR(db);
+ goto out;
+ }
+
+ hdr = (void *)db->data;
country = &hdr->country[0];
while (country->coll_ptr) {
- if (alpha2_equal(alpha2, country->alpha2))
- return regdb_query_country(regdb, country);
+ if (alpha2_equal(alpha2, country->alpha2)) {
+ err = regdb_query_country(db, country);
+ goto out;
+ }
country++;
}
- return -ENODATA;
+ err = -ENODATA;
+ out:
+ rcu_read_unlock();
+ return err;
}
static void regdb_fw_cb(const struct firmware *fw, void *context)
{
+ const struct firmware *db;
+
+ rtnl_lock();
+
+ db = rcu_dereference_protected(regdb, lockdep_rtnl_is_held());
+
+ if (WARN_ON(db)) {
+ release_firmware(fw);
+ goto out;
+ }
+
if (!fw) {
pr_info("failed to load regulatory.db\n");
if (fwregdb_attempts-- == 0)
- regdb = ERR_PTR(-ENODATA);
+ rcu_assign_pointer(regdb, ERR_PTR(-ENODATA));
goto restore;
}
if (!valid_regdb(fw)) {
pr_info("loaded regulatory.db is malformed\n");
release_firmware(fw);
- regdb = ERR_PTR(-EINVAL);
+ rcu_assign_pointer(regdb, ERR_PTR(-EINVAL));
goto restore;
}
- regdb = fw;
- if (query_regdb(context))
+ rcu_assign_pointer(regdb, fw);
+
+ if (context && query_regdb(context))
goto restore;
- goto free;
+ goto out;
+
restore:
- rtnl_lock();
restore_regulatory_settings(true);
+ out:
rtnl_unlock();
- free:
kfree(context);
+
+ if (!IS_ERR_OR_NULL(db)) {
+ synchronize_rcu();
+ release_firmware(db);
+ }
}
static int query_regdb_file(const char *alpha2)
@@ -813,6 +842,31 @@ static int query_regdb_file(const char *alpha2)
(void *)alpha2, regdb_fw_cb);
}
+int reg_reload_regdb(void)
+{
+ const struct firmware *db, *old;
+ int err;
+
+ err = request_firmware(&db, "regulatory.db", ®_pdev->dev);
+ if (err)
+ return err;
+
+ if (!valid_regdb(db))
+ return -ENODATA;
+
+ rtnl_lock();
+ old = rcu_dereference_protected(regdb, lockdep_rtnl_is_held());
+ rcu_assign_pointer(regdb, db);
+ rtnl_unlock();
+
+ if (!IS_ERR_OR_NULL(old)) {
+ synchronize_rcu();
+ release_firmware(old);
+ }
+
+ return 0;
+}
+
static bool reg_query_database(struct regulatory_request *request)
{
/* query internal regulatory database (if it exists) */
@@ -3564,5 +3618,5 @@ void regulatory_exit(void)
}
if (!IS_ERR_OR_NULL(regdb))
- release_firmware(regdb);
+ release_firmware(rcu_access_pointer(regdb));
}
diff --git a/net/wireless/reg.h b/net/wireless/reg.h
index ca7fedf2e7a1..9529c522611a 100644
--- a/net/wireless/reg.h
+++ b/net/wireless/reg.h
@@ -179,4 +179,10 @@ void regulatory_propagate_dfs_state(struct wiphy *wiphy,
* @wiphy2 - wiphy it's dfs_region to be checked against that of wiphy1
*/
bool reg_dfs_domain_same(struct wiphy *wiphy1, struct wiphy *wiphy2);
+
+/**
+ * reg_reload_regdb - reload the regulatory.db firmware file
+ */
+int reg_reload_regdb(void);
+
#endif /* __NET_WIRELESS_REG_H */
--
2.14.1
