[Buildroot] [PATCH v7 03/18] core: re-enter make if $(CURDIR) or $(O) are not absolute canonical path

[Yann E. MORIN <yann.morin.1998@free.fr>]

Matthew, All,

On 2016-03-20 20:45 -0500, Matthew Weber spake thusly:
> On Sun, Mar 20, 2016 at 8:44 PM, Matthew Weber <matt@thewebers.ws> wrote:
> > On Wed, Mar 9, 2016 at 4:58 PM, Samuel Martin <s.martin49@gmail.com> wrote:
> >> When $(CURDIR) or $(O) contain symlinks (or mount-bind) in their path,
> >> they can be resolved differently, depending on each package build-system
> >> (whether it uses the given paths or get the absolute canonical ones).
> >>
> >> Thus, to make easier tracking down host machine paths leaking into the
> >> host, target or staging trees, the CURDIR and O variables are set to
> >> their absolute canonical paths.
> >>
> >> Note that this change takes care of the makefile wrapper installed in
> >> $(O) to avoid unneeded make recursion.
> >>
> >> Signed-off-by: Samuel Martin <s.martin49@gmail.com>
> >>
> >> ---
> >> changes v6->v7:
> >> - none
> >>
> >> changes v5->v6:
> >> - new patch
> >> ---
> >>  Makefile | 22 ++++++++++++++++++----
> >>  1 file changed, 18 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/Makefile b/Makefile
> >> index 98c8dc7..52a92f6 100644
> >> --- a/Makefile
> >> +++ b/Makefile
> >> @@ -26,16 +26,30 @@
> >>
> >>  # Trick for always running with a fixed umask
> >>  UMASK = 0022
> >> -ifneq ($(shell umask),$(UMASK))
> >> +
> >> +# Check if we need to re-enter make for one or several of the following reasons:
> >> +# 1- Wrong (too restrictive) umask:
> >> +#    This prevents Buildroot and packages from creating files and directories.
> >> +# 2- CWD (i.e. $(CURDIR)) not being the absolute canonical path:
> >> +#    This makes harder tracking and fixing host machine path leaks.
> >> +# 3- Output location (i.e. $(O)) not being the absolute canonical path:
> >> +#    This makes harder tracking and fixing host machine path leaks.
> >> +#
> >> +# Note:
> >> +# - remove the trailing '/.' from $(O) as it can be added by the makefile
> >> +#   wrapper installed in the $(O).
> >> +ifneq ($(shell umask):$(CURDIR):$(patsubst %/.,%,$(O)),$(UMASK):$(realpath $(CURDIR)):$(realpath $(O)))
> >>  .PHONY: _all $(MAKECMDGOALS)
> >>
> >>  $(MAKECMDGOALS): _all
> >>         @:
> >>
> >>  _all:
> >> -       @umask $(UMASK) && $(MAKE) --no-print-directory $(MAKECMDGOALS)
> >> +       umask $(UMASK) && \
> >> +               $(MAKE) -C $(realpath $(CURDIR)) --no-print-directory \
> >> +                       $(MAKECMDGOALS) O=$(realpath $(O))
> >
> > I've applied your v7 patches with these changes to the tip of
> > buildroot and currently run into the following error.  I'm still
> > poking around trying to understand why.
> >
> > $ make V=1 qemu_x86_defconfig
> > umask 0022 && \
> >         make -C /opt/buildroot --no-print-directory \
> >                 qemu_x86_defconfig O=

Why are you opassing an empty O= option here?

Can you reproduce without it?

Regards,
Yann E. MORIN.

> > mkdir: missing operand
> > Try 'mkdir --help' for more information.
> > Makefile:156: *** output directory "" does not exist.  Stop.
> > Makefile:48: recipe for target '_all' failed
> > make: *** [_all] Error 2
> >
> > <snip>
> >
> > --
> > Thanks,
> > Matt
> 
> Sorry, didn't CC.  2nd attempt, see above.
> 
> -- 
> Thanks,
> Matt
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> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

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