oprofilefs: add missing ->i_mutex locking in object creation

Right now it's safe only during initial mount *and* functions are asking
to be abused for dynamic adding of objects.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 13 insertions, 3 deletions

diff --git a/drivers/oprofile/oprofilefs.c b/drivers/oprofile/oprofilefs.c
index 849357c1045c..445ffda715ad 100644
--- a/drivers/oprofile/oprofilefs.c
+++ b/drivers/oprofile/oprofilefs.c
@@ -139,17 +139,22 @@ static int __oprofilefs_create_file(struct super_block *sb,
         struct dentry *dentry;
         struct inode *inode;
 
+        mutex_lock(&root->d_inode->i_mutex);
         dentry = d_alloc_name(root, name);
-        if (!dentry)
+        if (!dentry) {
+                mutex_unlock(&root->d_inode->i_mutex);
                 return -ENOMEM;
+        }
         inode = oprofilefs_get_inode(sb, S_IFREG | perm);
         if (!inode) {
                 dput(dentry);
+                mutex_unlock(&root->d_inode->i_mutex);
                 return -ENOMEM;
         }
         inode->i_fop = fops;
+        inode->i_private = priv;
         d_add(dentry, inode);
-        dentry->d_inode->i_private = priv;
+        mutex_unlock(&root->d_inode->i_mutex);
         return 0;
 }
 
@@ -212,17 +217,22 @@ struct dentry *oprofilefs_mkdir(struct super_block *sb,
         struct dentry *dentry;
         struct inode *inode;
 
+        mutex_lock(&root->d_inode->i_mutex);
         dentry = d_alloc_name(root, name);
-        if (!dentry)
+        if (!dentry) {
+                mutex_unlock(&root->d_inode->i_mutex);
                 return NULL;
+        }
         inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
         if (!inode) {
                 dput(dentry);
+                mutex_unlock(&root->d_inode->i_mutex);
                 return NULL;
         }
         inode->i_op = &simple_dir_inode_operations;
         inode->i_fop = &simple_dir_operations;
         d_add(dentry, inode);
+        mutex_unlock(&root->d_inode->i_mutex);
         return dentry;
 }