linux-kernel - Re: [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections from bzImage

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]

Message-ID: <20200222162225.GA3326744@rani.riverdale.lan>
Date:   Sat, 22 Feb 2020 11:22:25 -0500
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Borislav Petkov <bp@...en8.de>
Cc:     Fangrui Song <maskray@...gle.com>,
        Nathan Chancellor <natechancellor@...il.com>,
        Arvind Sankar <nivedita@...m.mit.edu>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org, clang-built-linux@...glegroups.com,
        Michael Matz <matz@...e.de>
Subject: Re: [PATCH 2/2] x86/boot/compressed: Remove unnecessary sections
 from bzImage

On Sat, Feb 22, 2020 at 08:42:54AM +0100, Borislav Petkov wrote:
> On Fri, Feb 21, 2020 at 11:21:44PM -0800, Fangrui Song wrote:
> > In GNU ld, it seems that .shstrtab .symtab and .strtab are special
> > cased. Neither the input section description *(.shstrtab) nor *(*)
> > discards .shstrtab . I feel that this is a weird case (probably even a bug)
> > that lld should not implement.
> 
> Ok, forget what the tools do for a second: why is .shstrtab special and
> why would one want to keep it?
> 
> Because one still wants to know what the section names of an object are
> or other tools need it or why?
> 
> Thx.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> https://people.kernel.org/tglx/notes-about-netiquette

.shstrtab is required by the ELF specification. The e_shstrndx field in
the ELF header is the index of .shstrtab, and each section in the
section table is required to have an sh_name that points into the
.shstrtab.