On Fri, Jul 3, 2015 at 8:09 AM, Marcin Niesluchowski
[off-list ref] wrote:
* Message credibility: Lets imagine simple service which collects logs via
unix sockets. There is no reliable way of identifying logging process.
getsockopt() with SO_PEERCRED option would give pid form cred structure, but
according to manual it may not be of actual logging process:
"The returned credentials are those that were in effect at the time of the
call to connect(2) or socketpair(2)."
- select(7)
There's SCM_CREDENTIALS, which is dangerous, but it's dangerous in
exactly the same way that your patches are dangerous. You're
collecting PID/TID when write(2) is called, and it's very easy to get
another process to call write(2) on your behalf, because write(2)
isn't supposed to collect credentials.
--Andy