linux-kernel - Re: [PATCH] tty: vt: conmakehash: cope with abs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAEHkU3V9L4NKUkwr8Gyo2ZWEVJsjYTqPRduYrHoHyVtdEfFEVQ@mail.gmail.com>
Date: Sat, 17 Aug 2024 15:52:13 +0200
From: Max Krummenacher <max.oss.09@...il.com>
To: Luca Weiss <luca.weiss@...rphone.com>
Cc: Max Krummenacher <max.krummenacher@...adex.com>, stable@...r.kernel.org, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Jiri Slaby <jirislaby@...nel.org>, 
	Uwe Kleine-König <u.kleine-koenig@...gutronix.de>, 
	linux-kernel@...r.kernel.org, linux-serial@...r.kernel.org
Subject: Re: [PATCH] tty: vt: conmakehash: cope with abs_srctree no longer in env

Hi Luca

On Sat, Aug 17, 2024 at 11:48 AM Luca Weiss <luca.weiss@...rphone.com> wrote:
>
> On Thu Jul 25, 2024 at 3:20 PM CEST, max.oss.09 wrote:
> > From: Max Krummenacher <max.krummenacher@...adex.com>
> >
> > conmakehash uses getenv("abs_srctree") from the environment to strip
> > the absolute path from the generated sources.
> > However since commit e2bad142bb3d ("kbuild: unexport abs_srctree and
> > abs_objtree") this environment variable no longer gets set.
> > Instead use basename() to indicate the used file in a comment of the
> > generated source file.
> >
> > Fixes: 3bd85c6c97b2 ("tty: vt: conmakehash: Don't mention the full path of the input in output")
> > Signed-off-by: Max Krummenacher <max.krummenacher@...adex.com>
> >
> > ---
> >
> >  drivers/tty/vt/conmakehash.c | 20 +++++++-------------
> >  1 file changed, 7 insertions(+), 13 deletions(-)
> >
> > diff --git a/drivers/tty/vt/conmakehash.c b/drivers/tty/vt/conmakehash.c
> > index dc2177fec715..82d9db68b2ce 100644
> > --- a/drivers/tty/vt/conmakehash.c
> > +++ b/drivers/tty/vt/conmakehash.c
> > @@ -11,6 +11,8 @@
> >   * Copyright (C) 1995-1997 H. Peter Anvin
> >   */
> >
> > +#include <libgen.h>
> > +#include <linux/limits.h>
>
> Hi Max,
>
> Not sure this is the best place to ask but this <linux/limits.h> include
> appears to rely on this file already being installed in /usr/include and
> is not taken from the Linux source tree that's being built.
>
> This mostly manifests in building Linux kernel e.g. in Alpine Linux
> package build if 'linux-headers' package is not being explicitly
> installed, failing with
>
>   drivers/tty/vt/conmakehash.c:15:10: fatal error: linux/limits.h: No such file or directory
>      15 | #include <linux/limits.h>
>         |          ^~~~~~~~~~~~~~~~
>   compilation terminated.
>
> Apparently this is (understandably) also a problem when building on
> macOS:
> https://lore.kernel.org/all/20240807-macos-build-support-v1-11-4cd1ded85694@samsung.com/
>
> I did try that linked patch a bit ago, but unfortunately didn't fix it
> for the Alpine Linux build environment.

This is a bug I introduced.

Masahiro Yamada already fixed it with [1].

Sorry about that.

Regards
Max

[1] https://lore.kernel.org/all/20240809160853.1269466-1-masahiroy@kernel.org/

>
> Any ideas?
>
> Regards
> Luca
>
>
> >  #include <stdio.h>
> >  #include <stdlib.h>
> >  #include <sysexits.h>
> > @@ -76,8 +78,8 @@ static void addpair(int fp, int un)
> >  int main(int argc, char *argv[])
> >  {
> >    FILE *ctbl;
> > -  const char *tblname, *rel_tblname;
> > -  const char *abs_srctree;
> > +  const char *tblname;
> > +  char base_tblname[PATH_MAX];
> >    char buffer[65536];
> >    int fontlen;
> >    int i, nuni, nent;
> > @@ -102,16 +104,6 @@ int main(int argc, char *argv[])
> >       }
> >      }
> >
> > -  abs_srctree = getenv("abs_srctree");
> > -  if (abs_srctree && !strncmp(abs_srctree, tblname, strlen(abs_srctree)))
> > -    {
> > -      rel_tblname = tblname + strlen(abs_srctree);
> > -      while (*rel_tblname == '/')
> > -     ++rel_tblname;
> > -    }
> > -  else
> > -    rel_tblname = tblname;
> > -
> >    /* For now we assume the default font is always 256 characters. */
> >    fontlen = 256;
> >
> > @@ -253,6 +245,8 @@ int main(int argc, char *argv[])
> >    for ( i = 0 ; i < fontlen ; i++ )
> >      nuni += unicount[i];
> >
> > +  strncpy(base_tblname, tblname, PATH_MAX);
> > +  base_tblname[PATH_MAX - 1] = 0;
> >    printf("\
> >  /*\n\
> >   * Do not edit this file; it was automatically generated by\n\
> > @@ -264,7 +258,7 @@ int main(int argc, char *argv[])
> >  #include <linux/types.h>\n\
> >  \n\
> >  u8 dfont_unicount[%d] = \n\
> > -{\n\t", rel_tblname, fontlen);
> > +{\n\t", basename(base_tblname), fontlen);
> >
> >    for ( i = 0 ; i < fontlen ; i++ )
> >      {
>