btrfs: fix uninitialized pointer free in add_inode_ref()

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix uninitialized pointer free in add_inode_ref()

The add_inode_ref() function does not initialize the "name" struct when

it is declared. If any of the following calls to "read_one_inode()

returns NULL,

dir = read_one_inode(root, parent_objectid);

if (!dir) {

ret = -ENOENT;

goto out;

}

inode = read_one_inode(root, inode_objectid);

if (!inode) {

ret = -EIO;

goto out;

}

then "name.name" would be freed on "out" before being initialized.

out:

...

kfree(name.name);

This issue was reported by Coverity with CID 1526744.