linux-kernel - Re: [PATCH 4/4] coredump: documentation for proc and sysctl]

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] [day] [month] [year] [list]

Date:	Tue, 30 Jan 2007 16:40:25 +0900
From:	"Kawai, Hidehiro" <hidehiro.kawai.ez@...achi.com>
To:	Pavel Machek <pavel@....cz>, Andrew Morton <akpm@...l.org>
Cc:	kernel list <linux-kernel@...r.kernel.org>,
	sugita <yumiko.sugita.yf@...achi.com>,
	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
	Satoshi OSHIMA <soshima@...hat.com>,
	"Hideo AOKI@...hat" <haoki@...hat.com>
Subject: Re: [PATCH 4/4] coredump: documentation for proc and sysctl]

Hi Pavel and Andrew,

Pavel Machek wrote:
>>This patch adds the documentation for the following parameters:
>>  /proc/<pid>/core_flags
>>  /proc/sys/kernel/core_flags_enable
> 
> Sysctl seems really strange to me. Either the feature is safe to use,
> or it is not. Users can already ulimit -c 0, and we do not have
> "/proc/sys/kernel/allow_users_to_disable_their_core_dumps".

Oh, I had forgotten that.  Thank you for pointing out.  The purpose of
this sysctl is to prevent a bad process from hiding its memory.
But as you say, this sysctl isn't enough for the purpose.

Andrew wrote:
> Does this feature have any security implications?  For example, there might
> be system administration programs which force a coredump on a "bad"
> process, and leave the core somewhere for the administrator to look at. 

I have never heard of the story that ulimit -c 0 bothered an
administrator who wanted to force a coredump.  So even without this
sysctl, the administrator wouldn't bother about security concerns.
I'll drop it from the next version.

Thanks,
-- 
Hidehiro Kawai
Hitachi, Ltd., Systems Development Laboratory


-
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/