Messages in this thread | | | Date | Thu, 27 Mar 2014 11:56:48 -0700 | From | Jeremy Allison <> | Subject | Re: Thoughts on credential switching |
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On Thu, Mar 27, 2014 at 11:46:39AM -0700, Andy Lutomirski wrote: > On Thu, Mar 27, 2014 at 11:26 AM, Jeremy Allison <jra@samba.org> wrote: > > > > Amen to that :-). > > > > However, after talking with Jeff and Jim at CollabSummit, > > I was 'encouraged' to make my opinions known on the list. > > > > To me, calling the creds handle a file descriptor just > > feels wrong. IT *isn't* an fd, you can't read/write/poll > > on it, and it's only done as a convenience to get the > > close-on-exec semantics and the fact that the creds are > > already hung off the fd's in kernel space. > > Windows calls these things "handles." Linux has "file descriptors," > and there's plenty of precedent for things that aren't files.
Sure, but there's a set of expectations around fd's that these things don't satisfy - IO-ops.
> > That way we can also make it clear this thing only has > > meaning to a thread group, and SHOULD NOT (and indeed > > preferably CAN NOT) be passed between processes. > > > > If you want those semantics, then stick a struct pid * in there for > the tgid of the cretor and make sure that current's tgid matches when > you try to use it. > > I think they'd be more useful without that check, though.
I'm more worried about leakage and unintended consequences here.
> BTW, what do you want to have happen on fork? I think they should keep working.
Yeah, that's true. I want them to keep working across fork, but not across exec or any other method of fd-passing.
Jeremy.
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