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From: Andreas Schwab <schwab@linux-m68k.org>
To: Joakim Tjernlund <joakim.tjernlund@transmode.se>
Cc: linux-kernel@vger.kernel.org
Subject: Re: ls -l  /proc/1/exe -> Permission denied
References: <OF6F10655B.C9BFC08D-ONC1257D18.003D22DF-C1257D18.003E2204@transmode.se>
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	<OF152BAB0C.4FB2E7A9-ONC1257D1B.0031887F-C1257D1B.0031B248@transmode.se>
X-Yow: Sign my PETITION.
Date: Sun, 20 Jul 2014 12:55:53 +0200
In-Reply-To: <OF152BAB0C.4FB2E7A9-ONC1257D1B.0031887F-C1257D1B.0031B248@transmode.se>
	(Joakim Tjernlund's message of "Sun, 20 Jul 2014 11:02:48 +0200")
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Joakim Tjernlund <joakim.tjernlund@transmode.se> writes:

> Andreas Schwab <schwab@linux-m68k.org> wrote on 2014/07/19 22:21:59:
>> 
>> Joakim Tjernlund <joakim.tjernlund@transmode.se> writes:
>> 
>> > Trying to real /proc/<pid>/exe I noticed I could not read links not 
>> > belonging to my user such as:
>> > jocke >  ls -l /proc/1/exe
>> >              ls: cannot read symbolic link /proc/1/exe: Permission 
> denied
>> >
>> > Is this expected?
>> 
>> Yes.  This information is considered private.
>
> I don't understand why though.

It would allow bypassing access restrictions.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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