CVE-2026-72368

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

cachefiles: Fix double unlock in nomemdalloc error path

When start_creating() fails and returns -ENOMEM, it has already released the parent directory lock in _startdirop():

static struct dentry *__start_dirop(...)
{
    ...
    inode_lock_nested(dir, I_MUTEX_PARENT);
    dentry = lookup_one_qstr_excl(name, parent, lookup_flags);
    if (IS_ERR(dentry))
        inode_unlock(dir);  <-- Lock released on error
    return dentry;
}

However, the nomemdalloc error path in cachefilesgetdirectory() unconditionally calls inodeunlock(dinode(dir)) again, causing a double unlock that corrupts the rwsem state.

This is a leftover from commit 7ab96df840e60 which replaced manual locking with startcreating() but failed to update the nomemdalloc path (while correctly updating mkdirerror and lookup_error paths).