wl12xx: remove redundant debugfs_remove_recursive() call

Upon rmmod, the <debugfs>/ieee80211/phyX dir is being removed.
later, we try to remove <debugfs>/ieee80211/phyX/wl12xx, which
might result in NULL dereference.

Remove the excessive debugfs_remove_recursive() call.
(consequently, there is no more need to save wl->rootdir)

Reported-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>

1 files changed, 16 insertions, 20 deletions

diff --git a/drivers/net/wireless/wl12xx/debugfs.c b/drivers/net/wireless/wl12xx/debugfs.c
index ec6077760157..36e7ec1e0c3b 100644
--- a/drivers/net/wireless/wl12xx/debugfs.c
+++ b/drivers/net/wireless/wl12xx/debugfs.c
@@ -293,12 +293,13 @@ static const struct file_operations gpio_power_ops = {
         .llseek = default_llseek,
 };
 
-static int wl1271_debugfs_add_files(struct wl1271 *wl)
+static int wl1271_debugfs_add_files(struct wl1271 *wl,
+                                     struct dentry *rootdir)
 {
         int ret = 0;
         struct dentry *entry, *stats;
 
-        stats = debugfs_create_dir("fw-statistics", wl->rootdir);
+        stats = debugfs_create_dir("fw-statistics", rootdir);
         if (!stats || IS_ERR(stats)) {
                 entry = stats;
                 goto err;
@@ -395,13 +396,13 @@ static int wl1271_debugfs_add_files(struct wl1271 *wl)
         DEBUGFS_FWSTATS_ADD(rxpipe, missed_beacon_host_int_trig_rx_data);
         DEBUGFS_FWSTATS_ADD(rxpipe, tx_xfr_host_int_trig_rx_data);
 
-        DEBUGFS_ADD(tx_queue_len, wl->rootdir);
-        DEBUGFS_ADD(retry_count, wl->rootdir);
-        DEBUGFS_ADD(excessive_retries, wl->rootdir);
+        DEBUGFS_ADD(tx_queue_len, rootdir);
+        DEBUGFS_ADD(retry_count, rootdir);
+        DEBUGFS_ADD(excessive_retries, rootdir);
 
-        DEBUGFS_ADD(gpio_power, wl->rootdir);
+        DEBUGFS_ADD(gpio_power, rootdir);
 
-        entry = debugfs_create_x32("debug_level", 0600, wl->rootdir,
+        entry = debugfs_create_x32("debug_level", 0600, rootdir,
                                    &wl12xx_debug_level);
         if (!entry || IS_ERR(entry))
                 goto err;
@@ -419,7 +420,7 @@ err:
 
 void wl1271_debugfs_reset(struct wl1271 *wl)
 {
-        if (!wl->rootdir)
+        if (!wl->stats.fw_stats)
                 return;
 
         memset(wl->stats.fw_stats, 0, sizeof(*wl->stats.fw_stats));
@@ -430,13 +431,13 @@ void wl1271_debugfs_reset(struct wl1271 *wl)
 int wl1271_debugfs_init(struct wl1271 *wl)
 {
         int ret;
+        struct dentry *rootdir;
 
-        wl->rootdir = debugfs_create_dir(KBUILD_MODNAME,
-                                         wl->hw->wiphy->debugfsdir);
+        rootdir = debugfs_create_dir(KBUILD_MODNAME,
+                                     wl->hw->wiphy->debugfsdir);
 
-        if (IS_ERR(wl->rootdir)) {
-                ret = PTR_ERR(wl->rootdir);
-                wl->rootdir = NULL;
+        if (IS_ERR(rootdir)) {
+                ret = PTR_ERR(rootdir);
                 goto err;
         }
 
@@ -450,7 +451,7 @@ int wl1271_debugfs_init(struct wl1271 *wl)
 
         wl->stats.fw_stats_update = jiffies;
 
-        ret = wl1271_debugfs_add_files(wl);
+        ret = wl1271_debugfs_add_files(wl, rootdir);
 
         if (ret < 0)
                 goto err_file;
@@ -462,8 +463,7 @@ err_file:
         wl->stats.fw_stats = NULL;
 
 err_fw:
-        debugfs_remove_recursive(wl->rootdir);
-        wl->rootdir = NULL;
+        debugfs_remove_recursive(rootdir);
 
 err:
         return ret;
@@ -473,8 +473,4 @@ void wl1271_debugfs_exit(struct wl1271 *wl)
 {
         kfree(wl->stats.fw_stats);
         wl->stats.fw_stats = NULL;
-
-        debugfs_remove_recursive(wl->rootdir);
-        wl->rootdir = NULL;
-
 }