[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#556522: hurd - using the login shell is insecure



Heya,

Justus Winter, le Sun 16 Jan 2011 05:49:55 +0100, a écrit :
> > Justus Winter, le Wed 12 Jan 2011 00:39:35 +0100, a écrit :
> > > diff -r a95557dc73eb daemons/getty.c
> > > --- a/daemons/getty.c	Tue Jan 11 00:00:32 2011 +0000
> > > +++ b/daemons/getty.c	Tue Jan 11 23:38:12 2011 +0000
> > > @@ -129,10 +129,10 @@
> > >  
> > >    if (tt && strcmp (tt->ty_type, "dialup") == 0)
> > >      /* Dialup lines time out (which is login's default).  */
> > > -    execl (_PATH_LOGIN, "login", "-e", arg, NULL);
> > > +    execl (_PATH_LOGIN, "login", "--no-passwd", "-aMOTD", "-e",
> > > arg, "login", NULL); else
> > >      /* Hardwired lines don't.  */
> > > -    execl (_PATH_LOGIN, "login", "-e", arg, "-aNOAUTH_TIMEOUT",
> > > NULL);
> > > +    execl (_PATH_LOGIN, "login", "--no-passwd", "-aMOTD", "-e",
> > > arg, "-aNOAUTH_TIMEOUT", "login", NULL); 
> > >    syslog (LOG_ERR, "%s: %m", _PATH_LOGIN);
> > 
> > Mmm, why these?
> 
> You've got a point here. After reading the login programs source I
> realized that 'login' is the default unprivileged user to use and that
> spawning this session requires no password (btw, is there documentation
> for hurds userspace tools that I am just unable to find?).

See hurd.info:

14 Authentication
*****************

FIXME: finish

14.3 login, loginpr
===================

> I'd argue to keep the -aMOTD though to prevent the motd from being
> shown before the user logs in

Actually that's due to another bug.

Samuel



Reply to: