From: Johannes Berg <[email protected]> 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 <[email protected]> --- 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
