From: "Albert Cahalan" <acahalan@gmail.com>
To: froese@gmx.de, B.Steinbrink@gmx.de, hurtta+gmane@siilo.fmi.fi,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [RFC/PATCH] revoke/frevoke system calls
Date: Sat, 22 Jul 2006 04:05:19 -0400 [thread overview]
Message-ID: <787b0d920607220105l21251402nc98381edbc27a0c5@mail.gmail.com> (raw)
Edgar Toernig writes:
> Bjvrn Steinbrink wrote:
>> In do_revoke() there is:
>>
>> + if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) {
>> + ret = -EPERM;
>> + goto out;
>>
>> That pretty much matches what the BSD manpage says.
>
> Urgs, so any user may remove mappings from another process and
> let it crash?
Two good solutions come to mind:
a. substitute the zero page
b. make the mapping private and touch it as if C-O-W happened
Other concerns:
Optionally excluding the current UID/TGID/TID would be good.
(some flags) A revokeat() call seems to be required. Be sure
to handle working directories. The controlling tty is special.
Flag processes with revoked ttys in /proc/*/stat please, so
that ps can report it properly without opening another file.
BTW, it is wonderful to see this happening.
next reply other threads:[~2006-07-22 8:05 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-07-22 8:05 Albert Cahalan [this message]
2006-08-07 10:45 ` [RFC/PATCH] revoke/frevoke system calls Pekka Enberg
2006-08-07 15:19 ` Albert Cahalan
[not found] <6AFvY-7ZK-15@gated-at.bofh.it>
2006-07-20 21:26 ` Bodo Eggert
2006-07-20 23:01 ` roucaries bastien
-- strict thread matches above, loose matches on Subject: below --
2006-07-20 12:07 Pekka J Enberg
2006-07-20 20:02 ` Kari Hurtta
2006-07-20 21:09 ` Björn Steinbrink
2006-07-21 22:16 ` Edgar Toernig
2006-07-22 0:19 ` Andrew Morton
2006-07-22 6:22 ` Pekka J Enberg
2006-07-22 6:59 ` Andrew Morton
2006-07-22 7:41 ` Pekka Enberg
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