From: Florian Weimer <fweimer@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>,
Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Jim Lieb <jlieb@panasas.com>,
"Eric W. Biederman" <ebiederm@xmission.com>,
LSM List <linux-security-module@vger.kernel.org>,
"Serge E. Hallyn" <serge@canonical.com>,
Kees Cook <keescook@chromium.org>,
Linux FS Devel <linux-fsdevel@vger.kernel.org>,
"Theodore Ts'o" <tytso@mit.edu>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
bfields@redhat.com, Jeff Layton <jlayton@redhat.com>
Subject: Re: Thoughts on credential switching
Date: Thu, 27 Mar 2014 16:41:27 +0100 [thread overview]
Message-ID: <533446A7.6020003@redhat.com> (raw)
In-Reply-To: <CALCETrUtRzViEYUNev1JNFZMms56uiw47YZezak0Z0PKgFneQA@mail.gmail.com>
On 03/27/2014 02:01 AM, Andy Lutomirski wrote:
> Essentially, it's a performance problem. knfsd has override_creds,
> and it can cache struct cred. But userspace doing the same thing
> (i.e. impersonating a user) has to do setresuid, setresgid, and
> setgroups, which kills performance, since it results in something like
> five RCU callbacks per impersonation round-trip.
Do you mean setfsuid instead of setresuid?
--
Florian Weimer / Red Hat Product Security Team
next prev parent reply other threads:[~2014-03-27 15:41 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-27 0:23 Thoughts on credential switching Andy Lutomirski
2014-03-27 0:42 ` Serge Hallyn
2014-03-27 1:01 ` Andy Lutomirski
2014-03-27 15:41 ` Florian Weimer [this message]
2014-03-27 16:21 ` Andy Lutomirski
2014-03-27 2:48 ` Jeff Layton
2014-03-27 3:05 ` Andy Lutomirski
2014-03-27 3:25 ` Jeff Layton
2014-03-27 14:08 ` Jeff Layton
2014-03-29 6:43 ` Alex Elsayed
2014-03-30 13:03 ` Theodore Ts'o
2014-03-30 18:56 ` Andy Lutomirski
2014-03-31 11:51 ` Jeff Layton
2014-03-31 18:06 ` Trond Myklebust
2014-03-31 18:12 ` Jeff Layton
2014-03-31 19:26 ` Andy Lutomirski
2014-03-31 20:14 ` Trond Myklebust
2014-03-31 21:25 ` Andy Lutomirski
2014-03-27 12:46 ` Florian Weimer
2014-03-27 13:02 ` Jeff Layton
2014-03-27 13:06 ` Florian Weimer
2014-03-27 13:33 ` Boaz Harrosh
2014-04-22 11:37 ` Florian Weimer
2014-04-22 12:14 ` Boaz Harrosh
2014-04-22 16:35 ` Jim Lieb
2014-03-27 14:01 ` Jeff Layton
2014-03-27 18:26 ` Jeremy Allison
2014-03-27 18:46 ` Andy Lutomirski
2014-03-27 18:56 ` Jeremy Allison
2014-03-27 19:02 ` Andy Lutomirski
2014-03-27 19:30 ` Jim Lieb
2014-03-27 19:45 ` Andy Lutomirski
2014-03-27 20:47 ` Jim Lieb
2014-03-27 21:19 ` Andy Lutomirski
2014-03-31 10:44 ` One Thousand Gnomes
2014-03-31 16:49 ` Andy Lutomirski
2014-04-01 20:22 ` One Thousand Gnomes
2014-03-31 19:05 ` Jeremy Allison
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