linux-kernel - Re: [PATCH 1/4] exec: Change uselib(2) IS

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: <87ftbwun0h.fsf@x220.int.ebiederm.org>
Date:   Tue, 19 May 2020 07:28:46 -0500
From:   ebiederm@...ssion.com (Eric W. Biederman)
To:     Andreas Schwab <schwab@...ux-m68k.org>
Cc:     Christian Brauner <christian.brauner@...ntu.com>,
        Jann Horn <jannh@...gle.com>,
        Kees Cook <keescook@...omium.org>,
        Al Viro <viro@...iv.linux.org.uk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>,
        Eric Biggers <ebiggers3@...il.com>,
        Dmitry Vyukov <dvyukov@...gle.com>,
        linux-fsdevel <linux-fsdevel@...r.kernel.org>,
        linux-security-module <linux-security-module@...r.kernel.org>,
        Linux API <linux-api@...r.kernel.org>,
        kernel list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/4] exec: Change uselib(2) IS_SREG() failure to EACCES

Andreas Schwab <schwab@...ux-m68k.org> writes:

> On Mai 19 2020, Eric W. Biederman wrote:
>
>> I am wondering if there are source trees for libc4 or libc5 around
>> anywhere that we can look at to see how usage of uselib evolved.
>
> libc5 is available from archive.debian.org.
>
> http://archive.debian.org/debian-archive/debian/pool/main/libc/libc/libc_5.4.46.orig.tar.gz

Interesting.

It appears that the old a.out code to make use of uselib remained in
the libc5 sources but it was all conditional on the being compiled not
to use ELF.

libc5 did provide a wrapper for the uselib system call.

It appears glibc also provides a wrapper for the uselib system call
named: uselib@...BC_2.2.5.

I don't see a glibc header file that provides a declaration for uselib
though.

So the question becomes did anyone use those glibc wrappers.

Eric