cfg80211: add assert_cfg80211_lock() to ensure proper protection

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 27 insertions, 2 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 39d40d1e06d..e347093ccc7 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -7,7 +7,6 @@
 #include <linux/if.h>
 #include <linux/module.h>
 #include <linux/err.h>
-#include <linux/mutex.h>
 #include <linux/list.h>
 #include <linux/nl80211.h>
 #include <linux/debugfs.h>
@@ -50,6 +49,8 @@ cfg80211_drv_by_wiphy_idx(int wiphy_idx)
         if (!wiphy_idx_valid(wiphy_idx))
                 return NULL;
 
+        assert_cfg80211_lock();
+
         list_for_each_entry(drv, &cfg80211_drv_list, list) {
                 if (drv->wiphy_idx == wiphy_idx) {
                         result = drv;
@@ -69,6 +70,8 @@ __cfg80211_drv_from_info(struct genl_info *info)
         struct net_device *dev;
         int err = -EINVAL;
 
+        assert_cfg80211_lock();
+
         if (info->attrs[NL80211_ATTR_WIPHY]) {
                 bywiphyidx = cfg80211_drv_by_wiphy_idx(
                                 nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
diff --git a/net/wireless/core.h b/net/wireless/core.h
index f3ab00cbf76..982cc6be348 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -10,6 +10,7 @@
 #include <linux/netdevice.h>
 #include <linux/kref.h>
 #include <linux/rbtree.h>
+#include <linux/mutex.h>
 #include <net/genetlink.h>
 #include <net/wireless.h>
 #include <net/cfg80211.h>
@@ -73,6 +74,11 @@ bool wiphy_idx_valid(int wiphy_idx)
 extern struct mutex cfg80211_mutex;
 extern struct list_head cfg80211_drv_list;
 
+static inline void assert_cfg80211_lock(void)
+{
+        BUG_ON(!mutex_is_locked(&cfg80211_mutex));
+}
+
 struct cfg80211_internal_bss {
         struct list_head list;
         struct rb_node rbn;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 130fc2561ba..e0d3879b885 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -7,7 +7,6 @@
 #include <linux/if.h>
 #include <linux/module.h>
 #include <linux/err.h>
-#include <linux/mutex.h>
 #include <linux/list.h>
 #include <linux/if_ether.h>
 #include <linux/ieee80211.h>
@@ -138,6 +137,8 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
         int i;
         u16 ifmodes = dev->wiphy.interface_modes;
 
+        assert_cfg80211_lock();
+
         hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_WIPHY);
         if (!hdr)
                 return -1;
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 47d505616a4..e49ac9b2ada 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -276,6 +276,8 @@ static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y)
 
 static bool regdom_changed(const char *alpha2)
 {
+        assert_cfg80211_lock();
+
         if (!cfg80211_regdomain)
                 return true;
         if (alpha2_equal(cfg80211_regdomain->alpha2, alpha2))
@@ -830,6 +832,8 @@ static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
         struct ieee80211_supported_band *sband;
         struct ieee80211_channel *chan;
 
+        assert_cfg80211_lock();
+
         sband = wiphy->bands[band];
         BUG_ON(chan_idx >= sband->n_channels);
         chan = &sband->channels[chan_idx];
@@ -1042,6 +1046,9 @@ static int reg_copy_regd(const struct ieee80211_regdomain **dst_regd,
 static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
                           const char *alpha2)
 {
+
+        assert_cfg80211_lock();
+
         /* All initial requests are respected */
         if (!last_request)
                 return 0;
@@ -1122,6 +1129,8 @@ int __regulatory_hint(struct wiphy *wiphy, enum reg_set_by set_by,
         bool intersect = false;
         int r = 0;
 
+        assert_cfg80211_lock();
+
         r = ignore_request(wiphy, set_by, alpha2);
 
         if (r == REG_INTERSECT) {
@@ -1217,6 +1226,8 @@ EXPORT_SYMBOL(regulatory_hint);
 static bool reg_same_country_ie_hint(struct wiphy *wiphy,
                         u32 country_ie_checksum)
 {
+        assert_cfg80211_lock();
+
         if (!last_request->wiphy)
                 return false;
         if (likely(last_request->wiphy != wiphy))
@@ -1583,6 +1594,8 @@ int set_regdom(const struct ieee80211_regdomain *rd)
 {
         int r;
 
+        assert_cfg80211_lock();
+
         /* Note that this doesn't update the wiphys, this is done below */
         r = __set_regdom(rd);
         if (r) {
@@ -1605,6 +1618,8 @@ int set_regdom(const struct ieee80211_regdomain *rd)
 /* Caller must hold cfg80211_mutex */
 void reg_device_remove(struct wiphy *wiphy)
 {
+        assert_cfg80211_lock();
+
         kfree(wiphy->regd);
         if (!last_request || !last_request->wiphy)
                 return;