Btrfs: hunting slab corruption

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 04428137d75..ab5419eea93 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -361,13 +361,16 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
                                    struct nameidata *nd)
 {
         struct inode * inode;
+        struct btrfs_root *root = btrfs_sb(dir->i_sb);
         ino_t ino;
         int ret;
 
         if (dentry->d_name.len > BTRFS_NAME_LEN)
                 return ERR_PTR(-ENAMETOOLONG);
 
+        mutex_lock(&root->fs_info->fs_mutex);
         ret = btrfs_inode_by_name(dir, dentry, &ino);
+        mutex_unlock(&root->fs_info->fs_mutex);
         if (ret < 0)
                 return ERR_PTR(ret);
         inode = NULL;
@@ -395,6 +398,7 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         unsigned char d_type = DT_UNKNOWN;
         int over = 0;
 
+        mutex_lock(&root->fs_info->fs_mutex);
         key.objectid = inode->i_ino;
         key.flags = 0;
         btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
@@ -446,6 +450,7 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
         ret = 0;
 err:
         btrfs_release_path(root, &path);
+        mutex_unlock(&root->fs_info->fs_mutex);
         return ret;
 }
 
@@ -667,8 +672,8 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                 inode->i_op = &btrfs_file_inode_operations;
         }
         dir->i_sb->s_dirt = 1;
-        btrfs_end_transaction(trans, root);
 out_unlock:
+        btrfs_end_transaction(trans, root);
         mutex_unlock(&root->fs_info->fs_mutex);
         if (drop_inode) {
                 inode_dec_link_count(inode);