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
Date: Sun, 20 Jul 2014 13:51:31 +0200 [thread overview]
Message-ID: <87bnskxn7g.fsf@igel.home> (raw)
In-Reply-To: <CAFLxGvyAzUwMqi5vAGzoUoP6J4m+6FGC-J4=zKG2ZGguTgO8cg@mail.gmail.com> (Richard Weinberger's message of "Sun, 20 Jul 2014 13:06:30 +0200")
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
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."
next prev parent reply other threads:[~2014-07-20 11:51 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-17 11:18 ls -l /proc/1/exe -> Permission denied Joakim Tjernlund
2014-07-18 12:58 ` Richard Weinberger
2014-07-18 13:49 ` Joakim Tjernlund
[not found] ` <OF542E7A59.842197B0-ONC1257D19.004B7FF4-C1257D19.004BEC7C@LocalDomain>
2014-07-18 15:05 ` Joakim Tjernlund
2014-07-19 20:06 ` Richard Weinberger
2014-07-19 20:21 ` Andreas Schwab
2014-07-20 9:02 ` Joakim Tjernlund
2014-07-20 10:55 ` Andreas Schwab
2014-07-20 11:06 ` Richard Weinberger
2014-07-20 11:19 ` Joakim Tjernlund
2014-07-20 11:51 ` Andreas Schwab [this message]
2014-07-20 12:05 ` Richard Weinberger
2014-07-20 12:05 ` Richard Weinberger
2014-07-20 19:15 ` Joakim Tjernlund
2014-07-20 20:00 ` Richard Weinberger
2014-07-20 22:05 ` Joakim Tjernlund
2014-07-20 12:08 ` Richard Weinberger
2014-07-21 17:48 ` Eric W. Biederman
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