Re: [hurd, commited] hurd: Use __trivfs_server_name instead of trivfs_server_name

[Samuel Thibault]

Florian Weimer, le sam. 01 janv. 2022 20:02:12 +0100, a ecrit:
> * Samuel Thibault:
> 
> > Florian Weimer, le sam. 01 janv. 2022 19:48:21 +0100, a ecrit:
> >> * Samuel Thibault via Libc-alpha:
> >> >> > +  if (&__trivfs_server_name && __trivfs_server_name
> >> >> > +      && __trivfs_server_name[0] == 'r'
> >> >> > +      && __trivfs_server_name[1] == 'a'
> >> >> > +      && __trivfs_server_name[2] == 'n'
> >> >> > +      && __trivfs_server_name[3] == 'd'
> >> >> > +      && __trivfs_server_name[4] == 'o'
> >> >> > +      && __trivfs_server_name[5] == 'm'
> >> >> > +      && __trivfs_server_name[6] == '\0')
> >> >> >      /* We are random, don't try to read ourselves!  */
> >> >> >      return length;
> >> >> 
> >> >> How does this work?  It's a new synbol name, so there's no definition,
> >> >> so the weak reference is always null.
> >> >
> >> > It is peeking it from the program.
> >> >
> >> > Basically the problem is that the random translator uses glibc, whose
> >> > malloc implementation started using /dev/random in glibc 2.34, thus
> >> > reading itself.
> >> 
> >> I still don't understand.  Why isn't the condition always false?
> >
> > The definition is in the random translator, which exports it in its
> > dynamic symbol table.
> 
> Oh, so there is a companion patch that is not reflected in the glibc
> sources?

Yes, it's there:

http://git.savannah.gnu.org/cgit/hurd/hurd.git/commit/?id=8c5eb657ff196a31a3230652823221f3fe805d73

Samuel