mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Ulrich Drepper <drepper@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: akpm@linux-foundation.org
Subject: [PATCH] CPU online file permission
Date: Sun, 29 Jul 2007 20:56:46 -0400	[thread overview]
Message-ID: <200707300056.l6U0ukUe021931@devserv.devel.redhat.com> (raw)

Is there a reason why the "online" file in the subdirectories for the CPUs
in /sys/devices/system isn't world-readable?  I cannot imagine it to be
security relevant especially now that a getcpu() syscall can be used to
determine what CPUa  thread runs on.

The file is useful to correctly implement the sysconf() function to return
the number of online CPUs.  In the presence of hotplug we currently cannot
provide this information.  The patch below should to it.


Signed-off-by: Ulrich Drepper <drepper@redhat.com>

--- drivers/base/cpu.c	2007-02-20 12:01:31.000000000 -0800
+++ drivers/base/cpu.c-new	2007-07-29 17:52:58.000000000 -0700
@@ -53,7 +53,7 @@
 		ret = count;
 	return ret;
 }
-static SYSDEV_ATTR(online, 0600, show_online, store_online);
+static SYSDEV_ATTR(online, 0644, show_online, store_online);
 
 static void __devinit register_cpu_control(struct cpu *cpu)
 {

             reply	other threads:[~2007-07-30  0:57 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-07-30  0:56 Ulrich Drepper [this message]
2007-07-30 23:57 ` Andrew Morton
2007-07-31  7:38   ` Rusty Russell

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=200707300056.l6U0ukUe021931@devserv.devel.redhat.com \
    --to=drepper@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®