linux-kernel - Re: ls -l /proc/1/exe -> Permission denied

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: <53CC1FC2.5000806@nod.at>
Date:	Sun, 20 Jul 2014 22:00:02 +0200
From:	Richard Weinberger <richard@....at>
To:	Joakim Tjernlund <joakim.tjernlund@...nsmode.se>
CC:	LKML <linux-kernel@...r.kernel.org>,
	Andreas Schwab <schwab@...ux-m68k.org>
Subject: Re: ls -l /proc/1/exe -> Permission denied

Am 20.07.2014 21:15, schrieb Joakim Tjernlund:
> Richard Weinberger <richard@....at> wrote on 2014/07/20 14:05:41:
>>
>> Am 20.07.2014 13:51, schrieb Andreas Schwab:
>>> Richard Weinberger <richard.weinberger@...il.com> writes:
>>>> Do you have an example?
>>>
>>> proc symlinks are special because they actually resolve to the inode.
>>
>> Ah. If an attacker manages the kernel to follow the symlink he could
>> indirectly access that file.
>> Thanks for pointing this out!
> 
> That is a big if, I read this as you don't trust the kernels impl.
> of proc sym links so paper over this with denying all other to read 
> trivial
> data such as the exe sym link.

Feel free to propose a solution for that. :-)

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