Re: [gentoo-portage-dev] [PATCH] ebuild.sh: Completely ban external commands in global scope

[Michał Górny]

W dniu pią, 08.09.2017 o godzinie 14∶48 -0400, użytkownik Alec Warner
napisał:
> Why PATH=/dev/null vs export PATH=""

+      # note: we can't use empty because it implies current directory

>
> On Thu, Sep 7, 2017 at 3:36 AM, Michał Górny <mgorny@g.o> wrote:
>
> > Dnia 31 sierpnia 2017 22:45:42 CEST, "Michał Górny" <mgorny@g.o>
> > napisał(a):
> > > Set PATH to /dev/null when sourcing the ebuild for dependency
> > > resolution
> > > in order to prevent shell from finding external commands via PATH
> > > lookup. While this does not prevent executing programs via full path,
> > > it
> > > should catch the majority of accidental uses.
> > >
> > > Closes: https://github.com/gentoo/portage/pull/199
> > >
> > > // Note: this can't be merged right now since we still have ebuilds
> > > // calling external commands; see:
> > > // https://bugs.gentoo.org/show_bug.cgi?id=629222
> >
> > Update: gentoo is green now
> >
> > > ---
> > > bin/ebuild.sh             | 6 +++++-
> > > bin/isolated-functions.sh | 4 ++++
> > > 2 files changed, 9 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/bin/ebuild.sh b/bin/ebuild.sh
> > > index c23561651..94a44d534 100755
> > > --- a/bin/ebuild.sh
> > > +++ b/bin/ebuild.sh
> > > @@ -80,8 +80,12 @@ else
> > >       done
> > >       unset funcs x
> > >
> > > +      # prevent the shell from finding external executables
> > > +      # note: we can't use empty because it implies current directory
> > > +      _PORTAGE_ORIG_PATH=${PATH}
> > > +      export PATH=/dev/null
> > >       command_not_found_handle() {
> > > -              die "Command not found while sourcing ebuild: ${*}"
> > > +              die "External commands disallowed while sourcing ebuild:
> >
> > ${*}"
> > >       }
> > > fi
> > >
> > > diff --git a/bin/isolated-functions.sh b/bin/isolated-functions.sh
> > > index e320f7132..b28e44f18 100644
> > > --- a/bin/isolated-functions.sh
> > > +++ b/bin/isolated-functions.sh
> > > @@ -121,6 +121,10 @@ __helpers_die() {
> > > }
> > >
> > > die() {
> > > +      # restore PATH since die calls basename & sed
> > > +      # TODO: make it pure bash
> > > +      [[ -n ${_PORTAGE_ORIG_PATH} ]] && PATH=${_PORTAGE_ORIG_PATH}
> > > +
> > >       set +x # tracing only produces useless noise here
> > >       local IFS=$' \t\n'
> > >
> >
> >
> > --
> > Best regards,
> > Michał Górny (by phone)
> >
> >

-- 
Best regards,
Michał Górny