[PATCH] [SCSI] megaraid_sas: remove sysfs dbg_lvl world writeable permissions

[PATCH] [SCSI] megaraid_sas: remove sysfs dbg_lvl world writeable permissions

[Casey Dahlin]

From: Bryn M. Reeves <bmr@redhat.com>

/sys/bus/pci/drivers/megaraid_sas/poll_mode_io defaults to being
world-writable, which seems bad (letting any user affect kernel driver
behavior).

This turns off group and user write permissions, so that on typical
production systems only root can write to it.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
---
 drivers/scsi/megaraid/megaraid_sas.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index a39addc..08a7f49 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -3451,7 +3451,7 @@ out:
 	return retval;
 }
 
-static DRIVER_ATTR(poll_mode_io, S_IRUGO|S_IWUGO,
+static DRIVER_ATTR(poll_mode_io, S_IRUGO|S_IWUSR,
 		megasas_sysfs_show_poll_mode_io,
 		megasas_sysfs_set_poll_mode_io);
 
-- 
1.6.2.5

Re: [PATCH] [SCSI] megaraid_sas: remove sysfs dbg_lvl world writeable permissions

[Eugene Teo]

On 12/02/2009 11:17 PM, Casey Dahlin wrote:
> From: Bryn M. Reeves<bmr@redhat.com>
>
> /sys/bus/pci/drivers/megaraid_sas/poll_mode_io defaults to being
> world-writable, which seems bad (letting any user affect kernel driver
> behavior).
>
> This turns off group and user write permissions, so that on typical
> production systems only root can write to it.
>
> Signed-off-by: Bryn M. Reeves<bmr@redhat.com>
> Signed-off-by: Casey Dahlin<cdahlin@redhat.com>

CC: Eugene Teo <eteo@redhat.com>

The subject should read: megaraid_sas: remove poll_mode_io world 
writeable permissions instead, and this has been assigned with 
CVE-2009-3939.

Thanks, Eugene
-- 
Eugene Teo / Red Hat Security Response Team

RE: [PATCH] [SCSI] megaraid_sas: remove sysfs dbg_lvl world writeable permissions

[Yang, Bo]

How do you turn on poll_mode_io?

Thanks,

Bo Yang

________________________________________
From: Eugene Teo [eteo@redhat.com]
Sent: Wednesday, December 02, 2009 7:08 PM
To: Casey Dahlin
Cc: linux-kernel@vger.kernel.org; Bryn M. Reeves; DL-MegaRAID Linux; James E.J. Bottomley; Andrew Morton; Yang Hongyang; Anand Gadiyar; Jiri Kosina; linux-scsi@vger.kernel.org
Subject: Re: [PATCH] [SCSI] megaraid_sas: remove sysfs dbg_lvl world writeable permissions

On 12/02/2009 11:17 PM, Casey Dahlin wrote:
> From: Bryn M. Reeves<bmr@redhat.com>
>
> /sys/bus/pci/drivers/megaraid_sas/poll_mode_io defaults to being
> world-writable, which seems bad (letting any user affect kernel driver
> behavior).
>
> This turns off group and user write permissions, so that on typical
> production systems only root can write to it.
>
> Signed-off-by: Bryn M. Reeves<bmr@redhat.com>
> Signed-off-by: Casey Dahlin<cdahlin@redhat.com>

CC: Eugene Teo <eteo@redhat.com>

The subject should read: megaraid_sas: remove poll_mode_io world
writeable permissions instead, and this has been assigned with
CVE-2009-3939.

Thanks, Eugene
--
Eugene Teo / Red Hat Security Response Team

RE: [PATCH] [SCSI] megaraid_sas: remove sysfs dbg_lvl world writeable permissions

[Bryn M. Reeves]

On Thu, 2009-12-03 at 08:01 -0700, Yang, Bo wrote:
> How do you turn on poll_mode_io?

Write to the file as root?

Bryn.