[systemd-devel] [PATCH] mounting /dev/pts noexec causes trouble for grantpts(3)

[Mike Kelly]

On Tue, Oct 12, 2010 at 08:11:58PM +0200, Lennart Poettering wrote:
> On Tue, 12.10.10 13:57, Mike Kelly (pioto at pioto.org) wrote:
> 
> > grantpt(3) failed: Exec format error
> 
> Hmm, can you elaborate on this? Why does executability help here?

Well, this code is failing its tests:

  http://git.pioto.org/gitweb?p=paludis.git;a=blob;f=paludis/util/pty.hh;hb=HEAD
  http://git.pioto.org/gitweb?p=paludis.git;a=blob;f=paludis/util/pty.cc;hb=HEAD
  http://git.pioto.org/gitweb?p=paludis.git;a=blob;f=paludis/util/pty_TEST.cc;hb=HEAD

specifically the grantpt part in _init in pty.cc, and that sets an errno
of ENOEXEC.

However, I've noticed that this test doesn't fail on other systems that
have /dev/pts mounted noexec. And, after doing a mount -o remount,exec
/dev/pts it passed. And it also passed after remounting it back to
noexec. So, there's some other oddity happening here that I'll have to
dig into further.

I can say that this test only started failing recently on systems that
I've started to run systemd on, and not others, though.

I'll see if I can find any other possible causes, though (like, a glibc
bug or something).

-- 
Mike Kelly