Re: race between vfs_rename and do_linkat (mv and link)

[Xavier Roche]

On Tue, Feb 15, 2022 at 5:06 PM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:
> Does POSIX actually make any promises in that area?

My understanding is that we inherit from the mandatory atomicity of
all rename calls
(https://pubs.opengroup.org/onlinepubs/000095399/functions/rename.html)
> That specification requires that the action of the function be atomic.

We also inherit from the link call that is required to be atomic
(https://pubs.opengroup.org/onlinepubs/009695399/functions/link.html)
> The link() function shall atomically create a new link for the existing file and the link count of the file shall be incremented by one