Re: file descripter leak in current with Qmail?

On Monday 07 June 2004 22:38, Robert Watson wrote:
> On Mon, 7 Jun 2004, Arjan van Leeuwen wrote:
> > On Monday 07 June 2004 21:42, you wrote:
> > > On Mon, 7 Jun 2004, Arjan van Leeuwen wrote:
> > > > > > In terms of debugging it: your first task it to identify if
> > > > > > there's one process that's holding all the fd's, or if it is
> > > > > > distributed over many proceses.  After that, you want to track
> > > > > > down what kind of fd is being left open, which may help you track
> > > > > > down why it's left open...
> > > > >
> > > > > Just as I'm reading this, I'm seeing the same thing on my -CURRENT
> > > > > server, which has a _very_ low load (atm, it's only routing the
> > > > > internet traffic for 3 users and serving SMTP for 2 of them). I'm
> > > > > also running qmail. The kernel is from June 6. How do I go about
> > > > > investigating this further?
> > > >
> > > > Replying to myself -
> > > > fstat shows all open files evenly distributed among the running
> > > > processes.
> > >
> > > It could be that this is related to the esd file descriptor leak
> > > problem also being reported.  You might also try the attached patch.
> >
> > I get a panic (address not allocated) when using the patch. I can't
> > write down any useful details about it right now, because although the
> > server has only 3 users, they're very disconcerned when I disrupt their
> > internet traffic :).
>
> Doh.  Sorry about that.  Revised patch attached.  I'm able to test the
> leak with the attached C file, and on my test box (now that it doesn't
> panic), the leak appears fixed for non-blocking accepts.

No problem, this patch works like a charm. Thanks!

Arjan

>
> Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
> robert_at_fledge.watson.org      Senior Research Scientist, McAfee Research
>
> Index: uipc_syscalls.c
> ===================================================================
> RCS file: /data/ncvs/src/sys/kern/uipc_syscalls.c,v
> retrieving revision 1.187
> diff -u -r1.187 uipc_syscalls.c
> --- uipc_syscalls.c	7 Jun 2004 09:59:50 -0000	1.187
> +++ uipc_syscalls.c	7 Jun 2004 20:21:30 -0000
> _at__at_ -253,7 +253,7 _at__at_
>  {
>  	struct filedesc *fdp;
>  	struct file *nfp = NULL;
> -	struct sockaddr *sa;
> +	struct sockaddr *sa = NULL;
>  	socklen_t namelen;
>  	int error;
>  	struct socket *head, *so;
> _at__at_ -285,7 +285,7 _at__at_
>  	if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->so_comp)) {
>  		ACCEPT_UNLOCK();
>  		error = EWOULDBLOCK;
> -		goto done;
> +		goto noconnection;
>  	}
>  	while (TAILQ_EMPTY(&head->so_comp) && head->so_error == 0) {
>  		if (head->so_state & SS_CANTRCVMORE) {
> _at__at_ -296,14 +296,14 _at__at_
>  		    "accept", 0);
>  		if (error) {
>  			ACCEPT_UNLOCK();
> -			goto done;
> +			goto noconnection;
>  		}
>  	}
>  	if (head->so_error) {
>  		error = head->so_error;
>  		head->so_error = 0;
>  		ACCEPT_UNLOCK();
> -		goto done;
> +		goto noconnection;
>  	}
>  	so = TAILQ_FIRST(&head->so_comp);
>  	KASSERT(!(so->so_qstate & SQ_INCOMP), ("accept1: so SQ_INCOMP"));
>
>
>
> !DSPAM:40c4d2d111291897510869!