LinuxLists.cc - [PATCH 0/2] Regex fixes for mips and x86 cross-compile

2021-07-08 08:59:13

Subject: [PATCH 0/2] Regex fixes for mips and x86 cross-compile

Trying to run the x86 relocs tool on a BSD based HOSTCC (cross
compilation environment) leads to errors like

VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux
CC arch/x86/boot/compressed/misc.o - due to: arch/x86/boot/compressed/../voffset.h
OBJCOPY arch/x86/boot/compressed/vmlinux.bin - due to: vmlinux
RELOCS arch/x86/boot/compressed/vmlinux.relocs - due to: vmlinux
empty (sub)expressionarch/x86/boot/compressed/Makefile:118: recipe for target 'arch/x86/boot/compressed/vmlinux.relocs' failed
make[3]: *** [arch/x86/boot/compressed/vmlinux.relocs] Error 1

and when cross compiling a MIPS kernel on a BSD based HOSTCC
we get errors like

SYNC include/config/auto.conf.cmd - due to: .config
egrep: empty (sub)expression
UPD include/config/kernel.release
HOSTCC scripts/dtc/dtc.o - due to target missing

It turns out that relocs.c on x86 uses patterns like

"something(|_end)"

while MIPS uses egrep with

(|MINOR_|PATCHLEVEL_)

In both cases it is not valid syntax or gives undefined results
according to POSIX 9.5.3 ERE Grammar

https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html

It seems to be silently accepted by the Linux regcmp() or egrep
implementation while a BSD host complains.

Such patterns can be replaced by a transformation like

"(|p1|p2)" -> "(p1|p2)?"

Test Linux:

root@letux:~# echo foo | egrep '^(|foo)$'
foo
root@letux:~# echo fool | egrep '^(foo)?$'
root@letux:~# echo fun | egrep '^(|foo)$'
root@letux:~# echo f | egrep '^(|foo)$'
root@letux:~# echo | egrep '^(|foo)$'

root@letux:~# echo foo | egrep '^(foo)?$'
foo
root@letux:~# echo fool | egrep '^(foo)?$'
root@letux:~# echo fun | egrep '^(foo)?$'
root@letux:~# echo f | egrep '^(foo)?$'
root@letux:~# echo | egrep '^(foo)?$'

root@letux:~#

Test BSD:

iMac:master hns$ echo foo | egrep '^(|foo)$'
egrep: empty (sub)expression
iMac:master hns$ echo fool | egrep '^(foo)?$'
egrep: empty (sub)expression
iMac:master hns$ echo fun | egrep '^(|foo)$'
egrep: empty (sub)expression
iMac:master hns$ echo f | egrep '^(|foo)$'
egrep: empty (sub)expression
iMac:master hns$ echo | egrep '^(|foo)$'
egrep: empty (sub)expression
iMac:master hns$ echo foo | egrep '^(foo)?$'
foo
iMac:master hns$ echo fool | egrep '^(foo)?$'
iMac:master hns$ echo fun | egrep '^(foo)?$'
iMac:master hns$ echo f | egrep '^(foo)?$'
iMac:master hns$ echo | egrep '^(foo)?$'

iMac:master hns$

H. Nikolaus Schaller (2):
x86/tools/relocs: Fix non-POSIX regexp
arch: mips: Fix non-POSIX regexp

arch/mips/Makefile | 2 +-
arch/x86/tools/relocs.c | 8 ++++----
2 files changed, 5 insertions(+), 5 deletions(-)

--
2.31.1

2021-07-19 20:13:41

by H. Nikolaus Schaller

[permalink] [raw]

Subject: Re: [PATCH 0/2] Regex fixes for mips and x86 cross-compile

Any chance that it gets merged?

> Am 08.07.2021 um 10:57 schrieb H. Nikolaus Schaller <[email protected]>:
>
> Trying to run the x86 relocs tool on a BSD based HOSTCC (cross
> compilation environment) leads to errors like
>
> VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux
> CC arch/x86/boot/compressed/misc.o - due to: arch/x86/boot/compressed/../voffset.h
> OBJCOPY arch/x86/boot/compressed/vmlinux.bin - due to: vmlinux
> RELOCS arch/x86/boot/compressed/vmlinux.relocs - due to: vmlinux
> empty (sub)expressionarch/x86/boot/compressed/Makefile:118: recipe for target 'arch/x86/boot/compressed/vmlinux.relocs' failed
> make[3]: *** [arch/x86/boot/compressed/vmlinux.relocs] Error 1
>
> and when cross compiling a MIPS kernel on a BSD based HOSTCC
> we get errors like
>
> SYNC include/config/auto.conf.cmd - due to: .config
> egrep: empty (sub)expression
> UPD include/config/kernel.release
> HOSTCC scripts/dtc/dtc.o - due to target missing
>
> It turns out that relocs.c on x86 uses patterns like
>
> "something(|_end)"
>
> while MIPS uses egrep with
>
> (|MINOR_|PATCHLEVEL_)
>
> In both cases it is not valid syntax or gives undefined results
> according to POSIX 9.5.3 ERE Grammar
>
> https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html
>
> It seems to be silently accepted by the Linux regcmp() or egrep
> implementation while a BSD host complains.
>
> Such patterns can be replaced by a transformation like
>
> "(|p1|p2)" -> "(p1|p2)?"
>
> Test Linux:
>
> root@letux:~# echo foo | egrep '^(|foo)$'
> foo
> root@letux:~# echo fool | egrep '^(foo)?$'
> root@letux:~# echo fun | egrep '^(|foo)$'
> root@letux:~# echo f | egrep '^(|foo)$'
> root@letux:~# echo | egrep '^(|foo)$'
>
> root@letux:~# echo foo | egrep '^(foo)?$'
> foo
> root@letux:~# echo fool | egrep '^(foo)?$'
> root@letux:~# echo fun | egrep '^(foo)?$'
> root@letux:~# echo f | egrep '^(foo)?$'
> root@letux:~# echo | egrep '^(foo)?$'
>
> root@letux:~#
>
> Test BSD:
>
> iMac:master hns$ echo foo | egrep '^(|foo)$'
> egrep: empty (sub)expression
> iMac:master hns$ echo fool | egrep '^(foo)?$'
> egrep: empty (sub)expression
> iMac:master hns$ echo fun | egrep '^(|foo)$'
> egrep: empty (sub)expression
> iMac:master hns$ echo f | egrep '^(|foo)$'
> egrep: empty (sub)expression
> iMac:master hns$ echo | egrep '^(|foo)$'
> egrep: empty (sub)expression
> iMac:master hns$ echo foo | egrep '^(foo)?$'
> foo
> iMac:master hns$ echo fool | egrep '^(foo)?$'
> iMac:master hns$ echo fun | egrep '^(foo)?$'
> iMac:master hns$ echo f | egrep '^(foo)?$'
> iMac:master hns$ echo | egrep '^(foo)?$'
>
> iMac:master hns$
>
>
> H. Nikolaus Schaller (2):
> x86/tools/relocs: Fix non-POSIX regexp
> arch: mips: Fix non-POSIX regexp
>
> arch/mips/Makefile | 2 +-
> arch/x86/tools/relocs.c | 8 ++++----
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> --
> 2.31.1
>

2021-07-19 21:03:59

by Nick Desaulniers

[permalink] [raw]

Subject: Re: [PATCH 0/2] Regex fixes for mips and x86 cross-compile

+ Masahiro, linux-kbuild (EOM)

On Mon, Jul 19, 2021 at 12:07 PM H. Nikolaus Schaller <[email protected]> wrote:
>
> Any chance that it gets merged?
>
> > Am 08.07.2021 um 10:57 schrieb H. Nikolaus Schaller <[email protected]>:
> >
> > Trying to run the x86 relocs tool on a BSD based HOSTCC (cross
> > compilation environment) leads to errors like
> >
> > VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux
> > CC arch/x86/boot/compressed/misc.o - due to: arch/x86/boot/compressed/../voffset.h
> > OBJCOPY arch/x86/boot/compressed/vmlinux.bin - due to: vmlinux
> > RELOCS arch/x86/boot/compressed/vmlinux.relocs - due to: vmlinux
> > empty (sub)expressionarch/x86/boot/compressed/Makefile:118: recipe for target 'arch/x86/boot/compressed/vmlinux.relocs' failed
> > make[3]: *** [arch/x86/boot/compressed/vmlinux.relocs] Error 1
> >
> > and when cross compiling a MIPS kernel on a BSD based HOSTCC
> > we get errors like
> >
> > SYNC include/config/auto.conf.cmd - due to: .config
> > egrep: empty (sub)expression
> > UPD include/config/kernel.release
> > HOSTCC scripts/dtc/dtc.o - due to target missing
> >
> > It turns out that relocs.c on x86 uses patterns like
> >
> > "something(|_end)"
> >
> > while MIPS uses egrep with
> >
> > (|MINOR_|PATCHLEVEL_)
> >
> > In both cases it is not valid syntax or gives undefined results
> > according to POSIX 9.5.3 ERE Grammar
> >
> > https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html
> >
> > It seems to be silently accepted by the Linux regcmp() or egrep
> > implementation while a BSD host complains.
> >
> > Such patterns can be replaced by a transformation like
> >
> > "(|p1|p2)" -> "(p1|p2)?"
> >
> > Test Linux:
> >
> > root@letux:~# echo foo | egrep '^(|foo)$'
> > foo
> > root@letux:~# echo fool | egrep '^(foo)?$'
> > root@letux:~# echo fun | egrep '^(|foo)$'
> > root@letux:~# echo f | egrep '^(|foo)$'
> > root@letux:~# echo | egrep '^(|foo)$'
> >
> > root@letux:~# echo foo | egrep '^(foo)?$'
> > foo
> > root@letux:~# echo fool | egrep '^(foo)?$'
> > root@letux:~# echo fun | egrep '^(foo)?$'
> > root@letux:~# echo f | egrep '^(foo)?$'
> > root@letux:~# echo | egrep '^(foo)?$'
> >
> > root@letux:~#
> >
> > Test BSD:
> >
> > iMac:master hns$ echo foo | egrep '^(|foo)$'
> > egrep: empty (sub)expression
> > iMac:master hns$ echo fool | egrep '^(foo)?$'
> > egrep: empty (sub)expression
> > iMac:master hns$ echo fun | egrep '^(|foo)$'
> > egrep: empty (sub)expression
> > iMac:master hns$ echo f | egrep '^(|foo)$'
> > egrep: empty (sub)expression
> > iMac:master hns$ echo | egrep '^(|foo)$'
> > egrep: empty (sub)expression
> > iMac:master hns$ echo foo | egrep '^(foo)?$'
> > foo
> > iMac:master hns$ echo fool | egrep '^(foo)?$'
> > iMac:master hns$ echo fun | egrep '^(foo)?$'
> > iMac:master hns$ echo f | egrep '^(foo)?$'
> > iMac:master hns$ echo | egrep '^(foo)?$'
> >
> > iMac:master hns$
> >
> >
> > H. Nikolaus Schaller (2):
> > x86/tools/relocs: Fix non-POSIX regexp
> > arch: mips: Fix non-POSIX regexp
> >
> > arch/mips/Makefile | 2 +-
> > arch/x86/tools/relocs.c | 8 ++++----
> > 2 files changed, 5 insertions(+), 5 deletions(-)
> >
> > --
> > 2.31.1
> >
>

--
Thanks,
~Nick Desaulniers

2021-08-03 16:03:12

by H. Nikolaus Schaller

[permalink] [raw]

Subject: Re: [PATCH 0/2] Regex fixes for mips and x86 cross-compile

Hi all,
any chance to get that reviewed and merged into v5.15-rc1 and backported to stable?
Thank you,
Nikolaus Schaller

> Am 19.07.2021 um 22:37 schrieb Nick Desaulniers <[email protected]>:
>
> + Masahiro, linux-kbuild (EOM)
>
> On Mon, Jul 19, 2021 at 12:07 PM H. Nikolaus Schaller <[email protected]> wrote:
>>
>> Any chance that it gets merged?
>>
>>> Am 08.07.2021 um 10:57 schrieb H. Nikolaus Schaller <[email protected]>:
>>>
>>> Trying to run the x86 relocs tool on a BSD based HOSTCC (cross
>>> compilation environment) leads to errors like
>>>
>>> VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux
>>> CC arch/x86/boot/compressed/misc.o - due to: arch/x86/boot/compressed/../voffset.h
>>> OBJCOPY arch/x86/boot/compressed/vmlinux.bin - due to: vmlinux
>>> RELOCS arch/x86/boot/compressed/vmlinux.relocs - due to: vmlinux
>>> empty (sub)expressionarch/x86/boot/compressed/Makefile:118: recipe for target 'arch/x86/boot/compressed/vmlinux.relocs' failed
>>> make[3]: *** [arch/x86/boot/compressed/vmlinux.relocs] Error 1
>>>
>>> and when cross compiling a MIPS kernel on a BSD based HOSTCC
>>> we get errors like
>>>
>>> SYNC include/config/auto.conf.cmd - due to: .config
>>> egrep: empty (sub)expression
>>> UPD include/config/kernel.release
>>> HOSTCC scripts/dtc/dtc.o - due to target missing
>>>
>>> It turns out that relocs.c on x86 uses patterns like
>>>
>>> "something(|_end)"
>>>
>>> while MIPS uses egrep with
>>>
>>> (|MINOR_|PATCHLEVEL_)
>>>
>>> In both cases it is not valid syntax or gives undefined results
>>> according to POSIX 9.5.3 ERE Grammar
>>>
>>> https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html
>>>
>>> It seems to be silently accepted by the Linux regcmp() or egrep
>>> implementation while a BSD host complains.
>>>
>>> Such patterns can be replaced by a transformation like
>>>
>>> "(|p1|p2)" -> "(p1|p2)?"
>>>
>>> Test Linux:
>>>
>>> root@letux:~# echo foo | egrep '^(|foo)$'
>>> foo
>>> root@letux:~# echo fool | egrep '^(foo)?$'
>>> root@letux:~# echo fun | egrep '^(|foo)$'
>>> root@letux:~# echo f | egrep '^(|foo)$'
>>> root@letux:~# echo | egrep '^(|foo)$'
>>>
>>> root@letux:~# echo foo | egrep '^(foo)?$'
>>> foo
>>> root@letux:~# echo fool | egrep '^(foo)?$'
>>> root@letux:~# echo fun | egrep '^(foo)?$'
>>> root@letux:~# echo f | egrep '^(foo)?$'
>>> root@letux:~# echo | egrep '^(foo)?$'
>>>
>>> root@letux:~#
>>>
>>> Test BSD:
>>>
>>> iMac:master hns$ echo foo | egrep '^(|foo)$'
>>> egrep: empty (sub)expression
>>> iMac:master hns$ echo fool | egrep '^(foo)?$'
>>> egrep: empty (sub)expression
>>> iMac:master hns$ echo fun | egrep '^(|foo)$'
>>> egrep: empty (sub)expression
>>> iMac:master hns$ echo f | egrep '^(|foo)$'
>>> egrep: empty (sub)expression
>>> iMac:master hns$ echo | egrep '^(|foo)$'
>>> egrep: empty (sub)expression
>>> iMac:master hns$ echo foo | egrep '^(foo)?$'
>>> foo
>>> iMac:master hns$ echo fool | egrep '^(foo)?$'
>>> iMac:master hns$ echo fun | egrep '^(foo)?$'
>>> iMac:master hns$ echo f | egrep '^(foo)?$'
>>> iMac:master hns$ echo | egrep '^(foo)?$'
>>>
>>> iMac:master hns$
>>>
>>>
>>> H. Nikolaus Schaller (2):
>>> x86/tools/relocs: Fix non-POSIX regexp
>>> arch: mips: Fix non-POSIX regexp
>>>
>>> arch/mips/Makefile | 2 +-
>>> arch/x86/tools/relocs.c | 8 ++++----
>>> 2 files changed, 5 insertions(+), 5 deletions(-)
>>>
>>> --
>>> 2.31.1
>>>
>>
>
>
> --
> Thanks,
> ~Nick Desaulniers

2021-08-05 17:06:08

by Masahiro Yamada

[permalink] [raw]

Subject: Re: [PATCH 0/2] Regex fixes for mips and x86 cross-compile

On Wed, Aug 4, 2021 at 12:59 AM H. Nikolaus Schaller <[email protected]> wrote:
>
> Hi all,
> any chance to get that reviewed and merged into v5.15-rc1 and backported to stable?
> Thank you,
> Nikolaus Schaller

I have a macbook (macOS catalina), and was able to
reproduce this issue.

I applied both to kbuild tree.
Thanks.

>
> > Am 19.07.2021 um 22:37 schrieb Nick Desaulniers <[email protected]>:
> >
> > + Masahiro, linux-kbuild (EOM)
> >
> > On Mon, Jul 19, 2021 at 12:07 PM H. Nikolaus Schaller <[email protected]> wrote:
> >>
> >> Any chance that it gets merged?
> >>
> >>> Am 08.07.2021 um 10:57 schrieb H. Nikolaus Schaller <[email protected]>:
> >>>
> >>> Trying to run the x86 relocs tool on a BSD based HOSTCC (cross
> >>> compilation environment) leads to errors like
> >>>
> >>> VOFFSET arch/x86/boot/compressed/../voffset.h - due to: vmlinux
> >>> CC arch/x86/boot/compressed/misc.o - due to: arch/x86/boot/compressed/../voffset.h
> >>> OBJCOPY arch/x86/boot/compressed/vmlinux.bin - due to: vmlinux
> >>> RELOCS arch/x86/boot/compressed/vmlinux.relocs - due to: vmlinux
> >>> empty (sub)expressionarch/x86/boot/compressed/Makefile:118: recipe for target 'arch/x86/boot/compressed/vmlinux.relocs' failed
> >>> make[3]: *** [arch/x86/boot/compressed/vmlinux.relocs] Error 1
> >>>
> >>> and when cross compiling a MIPS kernel on a BSD based HOSTCC
> >>> we get errors like
> >>>
> >>> SYNC include/config/auto.conf.cmd - due to: .config
> >>> egrep: empty (sub)expression
> >>> UPD include/config/kernel.release
> >>> HOSTCC scripts/dtc/dtc.o - due to target missing
> >>>
> >>> It turns out that relocs.c on x86 uses patterns like
> >>>
> >>> "something(|_end)"
> >>>
> >>> while MIPS uses egrep with
> >>>
> >>> (|MINOR_|PATCHLEVEL_)
> >>>
> >>> In both cases it is not valid syntax or gives undefined results
> >>> according to POSIX 9.5.3 ERE Grammar
> >>>
> >>> https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html
> >>>
> >>> It seems to be silently accepted by the Linux regcmp() or egrep
> >>> implementation while a BSD host complains.
> >>>
> >>> Such patterns can be replaced by a transformation like
> >>>
> >>> "(|p1|p2)" -> "(p1|p2)?"
> >>>
> >>> Test Linux:
> >>>
> >>> root@letux:~# echo foo | egrep '^(|foo)$'
> >>> foo
> >>> root@letux:~# echo fool | egrep '^(foo)?$'
> >>> root@letux:~# echo fun | egrep '^(|foo)$'
> >>> root@letux:~# echo f | egrep '^(|foo)$'
> >>> root@letux:~# echo | egrep '^(|foo)$'
> >>>
> >>> root@letux:~# echo foo | egrep '^(foo)?$'
> >>> foo
> >>> root@letux:~# echo fool | egrep '^(foo)?$'
> >>> root@letux:~# echo fun | egrep '^(foo)?$'
> >>> root@letux:~# echo f | egrep '^(foo)?$'
> >>> root@letux:~# echo | egrep '^(foo)?$'
> >>>
> >>> root@letux:~#
> >>>
> >>> Test BSD:
> >>>
> >>> iMac:master hns$ echo foo | egrep '^(|foo)$'
> >>> egrep: empty (sub)expression
> >>> iMac:master hns$ echo fool | egrep '^(foo)?$'
> >>> egrep: empty (sub)expression
> >>> iMac:master hns$ echo fun | egrep '^(|foo)$'
> >>> egrep: empty (sub)expression
> >>> iMac:master hns$ echo f | egrep '^(|foo)$'
> >>> egrep: empty (sub)expression
> >>> iMac:master hns$ echo | egrep '^(|foo)$'
> >>> egrep: empty (sub)expression
> >>> iMac:master hns$ echo foo | egrep '^(foo)?$'
> >>> foo
> >>> iMac:master hns$ echo fool | egrep '^(foo)?$'
> >>> iMac:master hns$ echo fun | egrep '^(foo)?$'
> >>> iMac:master hns$ echo f | egrep '^(foo)?$'
> >>> iMac:master hns$ echo | egrep '^(foo)?$'
> >>>
> >>> iMac:master hns$
> >>>
> >>>
> >>> H. Nikolaus Schaller (2):
> >>> x86/tools/relocs: Fix non-POSIX regexp
> >>> arch: mips: Fix non-POSIX regexp
> >>>
> >>> arch/mips/Makefile | 2 +-
> >>> arch/x86/tools/relocs.c | 8 ++++----
> >>> 2 files changed, 5 insertions(+), 5 deletions(-)
> >>>
> >>> --
> >>> 2.31.1
> >>>
> >>
> >
> >
> > --
> > Thanks,
> > ~Nick Desaulniers
>

--
Best Regards
Masahiro Yamada