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From: Andreas Schwab <schwab@linux-m68k.org>
To: Richard Weinberger <richard.weinberger@gmail.com>
Cc: Joakim Tjernlund <joakim.tjernlund@transmode.se>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: ls -l /proc/1/exe -> Permission denied
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Date: Sun, 20 Jul 2014 13:51:31 +0200
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	(Richard Weinberger's message of "Sun, 20 Jul 2014 13:06:30 +0200")
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Richard Weinberger <richard.weinberger@gmail.com> writes:

> On Sun, Jul 20, 2014 at 12:55 PM, Andreas Schwab <schwab@linux-m68k.org> wrote:
>> 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.
>
> Do you have an example?

proc symlinks are special because they actually resolve to the inode.

Andreas.

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