On 8/30/17 10:41 AM, ebied...@xmission.com wrote:
Prakash Sangappa <prakash.sanga...@oracle.com> writes:
With regards to security, the question basically is what is the consequence
of passing the wrong id. As I understand it, Interpreting the id to be pid
or tid, the effective uid and gid will be the same. It would be a problem
only if the incorrect interpretation of the id would refer a different process.
But that cannot happen as the the global tid(gettid() of a thread is
unique.
There is also the issue that the receiving process could look, not see
the pid in proc and assume the sending process is dead. That I suspect
is the larger danger.
Will this not be a bug in the application, if it is sending the wrong id?
As long as the thread is alive, that id cannot reference another process /
thread.
Unless the thread were to exit and the id gets recycled and got used for another
thread or process. This would be no different from a process exiting and its
pid getting recycled which is the case now.
Largely I agree.
If all you want are pid translations I suspect the are far easier ways
thant updating the SCM_CREDENTIALS code.
What would be an another easier & efficient way of doing pid translation?
Should a new API/mechanism be considered mainly for pid translation purpose
for use with pid namespaces, say based on 'pipe' something similar to
I_SENDFD?
Thanks,
-Prakash.
Eric
