Re: linux-next: Tree for July 28 ("copy_from_user_overflow" undefined)

From: Sedat Dilek
Date: Fri Jul 29 2011 - 05:02:14 EST


On Fri, Jul 29, 2011 at 7:09 AM, Randy Dunlap <rdunlap@xxxxxxxxxxxx> wrote:
> On Fri, 29 Jul 2011 03:34:26 +0200 Sedat Dilek wrote:
>
>> On Fri, Jul 29, 2011 at 1:01 AM, Randy Dunlap <rdunlap@xxxxxxxxxxxx> wrote:
>> > On Thu, 28 Jul 2011 16:05:31 +0200 Sedat Dilek wrote:
>> >
>> >> Hi,
>> >>
>> >> just see this build-break on the last mile:
>> >>
>> >> [...]
>> >> Â OBJCOPY arch/x86/boot/compressed/vmlinux.bin
>> >> Â HOSTCC Âarch/x86/boot/compressed/relocs
>> >> Â HOSTCC Âarch/x86/boot/compressed/mkpiggy
>> >> /mnt/sdb3/linux-kernel/linux-3.0/debian/build/source_i386_none/arch/x86/boot/compressed/relocs.c:
>> >> In function 'print_absolute_symbols':
>> >> /mnt/sdb3/linux-kernel/linux-3.0/debian/build/source_i386_none/arch/x86/boot/compressed/relocs.c:405:14:
>> >> warning: variable 'sh_symtab' set but not used
>> >> [-Wunused-but-set-variable]
>> >> ERROR: "copy_from_user_overflow" [fs/binfmt_misc.ko] undefined!
>> >> make[5]: *** [__modpost] Error 1
>> >> make[4]: *** [modules] Error 2
>> >> make[4]: *** Waiting for unfinished jobs....
>> >> Â RELOCS Âarch/x86/boot/compressed/vmlinux.relocs
>> >> Â GZIP Â Âarch/x86/boot/compressed/vmlinux.bin.gz
>> >> Â MKPIGGY arch/x86/boot/compressed/piggy.S
>> >> Â AS Â Â Âarch/x86/boot/compressed/piggy.o
>> >> Â LD Â Â Âarch/x86/boot/compressed/vmlinux
>> >> Â ZOFFSET arch/x86/boot/zoffset.h
>> >> Â OBJCOPY arch/x86/boot/vmlinux.bin
>> >> Â AS Â Â Âarch/x86/boot/header.o
>> >> Â LD Â Â Âarch/x86/boot/setup.elf
>> >> Â OBJCOPY arch/x86/boot/setup.bin
>> >> Â BUILD Â arch/x86/boot/bzImage
>> >> Setup is 15596 bytes (padded to 15872 bytes).
>> >> System is 2471 kB
>> >> CRC eb598167
>> >> Kernel: arch/x86/boot/bzImage is ready Â(#1)
>> >> make[3]: *** [sub-make] Error 2
>> >> make[2]: *** [all] Error 2
>> >>
>> >> I have these binfmt kernel-config options set:
>> >>
>> >> CONFIG_BINFMT_ELF=y
>> >> # CONFIG_BINFMT_AOUT is not set
>> >> CONFIG_BINFMT_MISC=m
>> >
>> > How does someone turn off this error message?
>> >
>> > I have:
>> > # CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is not set
>> > # CONFIG_STRICT_DEVMEM is not set
>> >
>> > and I still cannot get this error to go away (on x86_64).
>> >
>> >
>> > ---
>> > ~Randy
>> > *** Remember to use Documentation/SubmitChecklist when testing your code ***
>> >
>>
>> Can you say with which linux-next version you saw this first?
>> My last version was next-20110722 (which was OK).
>
> It looks like 2011-0727 has lots of these errors in my randconfig builds,
> but I can't say that they are all incorrect, so it's not very conclusive.
>
> ---
> ~Randy
> *** Remember to use Documentation/SubmitChecklist when testing your code ***
>

I can confirm next-20110726 is fine.

# egrep 'BINFMT|DEBUG_STRICT_USER_COPY_CHECKS|STRICT_DEVMEM'
/boot/config-3.0.0-next20110726.3-686-small
CONFIG_BINFMT_ELF=y
CONFIG_BINFMT_AOUT=m
CONFIG_BINFMT_MISC=m
CONFIG_STRICT_DEVMEM=y
# CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is not set

So, the binfmt_misc culprit was introduced between next-20110726
(good) and next-20110727 (bad).
I'll try to look into the diff, but can't promise.

- Sedat -
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/