linux-kernel - Re: [PATCH v2 4/5] efi/x86: Remove extra headroom for setup block

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Mon, 11 May 2020 14:36:45 -0400
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Mike Lothian <mike@...eburn.co.uk>
Cc:     nivedita@...m.mit.edu, Ard Biesheuvel <ardb@...nel.org>,
        linux-efi@...r.kernel.org, linux-kernel@...r.kernel.org,
        x86@...nel.org
Subject: Re: [PATCH v2 4/5] efi/x86: Remove extra headroom for setup block

On Mon, May 11, 2020 at 06:01:49PM +0100, Mike Lothian wrote:
> Hi
> 
> This patch has been causing issues for me since switching to GCC 10.1:
> 
>   CALL    scripts/checksyscalls.sh
>   CALL    scripts/atomic/check-atomics.sh
>   DESCEND  objtool
>   CHK     include/generated/compile.h
>   HOSTCC  arch/x86/boot/tools/build
> /usr/lib/gcc/x86_64-pc-linux-gnu/10.1.0/../../../../x86_64-pc-linux-gnu/bin/ld: error: linker defined: multiple definition of '_end'
> /usr/lib/gcc/x86_64-pc-linux-gnu/10.1.0/../../../../x86_64-pc-linux-gnu/bin/ld: /tmp/ccEkW0jM.o: previous definition here
> collect2: error: ld returned 1 exit status
> make[1]: *** [scripts/Makefile.host:103: arch/x86/boot/tools/build] Error 1
> make: *** [arch/x86/Makefile:303: bzImage] Error 2
> 
> Cheers
> 
> Mike

I'm not getting an error even with gcc 10 for some reason, but I can see
that it is busted. It's using the linker-defined _end symbol which is
just pass the end of the .bss.

Does adding "static" to the declaration of _end fix your error?