linux-kernel - [PATCH 0/3] kconfig: Make 'm' safe before modules symbol is defined

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Date:   Thu,  5 Oct 2017 14:01:12 +0200
From:   Ulf Magnusson <ulfalizer@...il.com>
To:     yann.morin.1998@...e.fr, linux-kbuild@...r.kernel.org
Cc:     sam@...nborg.org, zippel@...ux-m68k.org, nicolas.pitre@...aro.org,
        mmarek@...e.com, dirk@...ders.net, yamada.masahiro@...ionext.com,
        lacombar@...il.com, JBeulich@...e.com,
        linux-kernel@...r.kernel.org, Ulf Magnusson <ulfalizer@...il.com>
Subject: [PATCH 0/3] kconfig: Make 'm' safe before modules symbol is defined

Hello,

This patchset fixes a segfault that occurs if 'm' appears in certain
expressions before the modules symbol is defined. The problem is that m is
rewritten to m && <modules symbol> already during parsing. Doing it in
menu_finalize(), which runs after parsing, fixes the problem.

To aid the review and people trying to understand menu_finalize() in the future
(including me), it also renames menu_check_dep() to rewrite_m() and adds
comments to clarify the existing expression rewriting and dependency
propagation logic.

The changes have been tested for regressions using zconfdump(), Kconfiglib, and
Valgrind.

Cheers,
Ulf

Ulf Magnusson (3):
  kconfig: Rename menu_check_dep() to rewrite_m()
  kconfig: Clarify expression rewriting
  kconfig: Clean up modules handling and fix crash

 scripts/kconfig/menu.c | 74 ++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 66 insertions(+), 8 deletions(-)

-- 
2.7.4