9p: Fix v9fs_issue_write() to update i_size and remote_i_size

In the Linux kernel, the following vulnerability has been resolved: 9p: Fix v9fs_issue_write() to update i_size and remote_i_size Fix v9fs_issue_write() to update i_size and remote_i_size to the new size of the server file if we made it larger, using the start fpos and the count returned by p9_client_write() to calculate the new minimum file size. This assumes that if the 9P server makes a short write (say it hits ENOSPC), a reduced count is returned.

Where it's fixed