Re: pkg/50995: sigsegv in recv()

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

On Sun, Apr 03, 2016 at 03:25:00AM +0000, David Holland wrote:
>  An out-of-range FD_SET will scribble outside of the fd_set, and since
>  the one here is on the stack, whatever's next on the stack gets a
>  present.

bug analyzed :-) Thanks!

>  The path of least resistance is #define FD_SETSIZE 512 (before
>  including anything) but rewriting to use poll is probably a better
>  choice. Especially for selecting on a single fd like this.

I am testing

CONFIGURE_ARGS+=        CPPFLAGS=-DFD_SETSIZE=512

I saw that solaris 7 uses 1024 by default. I think we might just have
been unlucky, as maxchildren = 250, so 512 should be enough. In the
patches I'm testing, I complain if it is not enough, so we won't get
the mysterious core dumps...

>  (while changing FD_SETSIZE is a traditional interface, it's probably
>  not very portable)
>  
>  Does the package have a viable upstream?

No, but e2guardian is looking promising. I already looked at using
kqueue instead, and saw:

  https://github.com/e2guardian/e2guardian/issues/88