Bug 441054

Created attachment 301376 [details]
/var/log/messages

*** Bug 440290 has been marked as a duplicate of this bug. ***

Any input on why udev is doing this Bill?  Or should I just revert to the old
initscript method of scanning hwconf for driver entries instead of using
udevtrigger?

udevtrigger generates events for the devices in /sys. I'm not sure why that
would cause a relabel, though.

Does echo '1' (or 'add') to /sys/block/sda/uevent cause the mislabeling as well?

I can't answer your question Bill, evidently none of my machines have selinux
enabled and so they all list the device as unlabeled.  Milan, can you check this?

(In reply to comment #4)
> Does echo '1' (or 'add') to /sys/block/sda/uevent cause the mislabeling as well?

Bingo!

# ls -Z /dev/sda
brw-r-----  root disk system_u:object_r:fixed_disk_device_t /dev/sda
# echo 1 > /sys/block/sda/uevent 
# ls -Z /dev/sda
brw-r-----  root disk system_u:object_r:device_t       /dev/sda

Created attachment 301574 [details]
/var/log/messages

If that helps, here's part of /var/log/messages showing what's happening after
# echo 1 > /sys/block/sda/uevent

Apr  8 06:19:46 ivy udevd-event[2820]: udev_node_mknod: preserve file
'/dev/sda', because it has correct dev_t

though it re-sets the selinux context...
                selinux_setfilecon(file, udev->dev->kernel_name, stats.st_mode);

on creation:
selinux_setfscreatecon:
   matchpathcon(file, mode, &scontext)
   setfscreatecon(scontext);
mknod(...);

in this case:
selinux_setfilecon:
   matchpathcon(file, mode, &scontext)
   setfilecon(file, scontext);


I don't see anything, which would trigger a wrong relabel.

Daniel?

At this point, my question is whether or not we have established that this isn't
really an openib bug and this needs to be switched to another component and
assigned to that person?

If the devices are recreated without going through the udev code path to
setfilecon or setfscreatecon they would end up labeled device_t.

(In reply to comment #10)
> At this point, my question is whether or not we have established that this isn't
> really an openib bug and this needs to be switched to another component and
> assigned to that person?

None of the openib bits have to be present for this problem to pop up. All you
have to do is to run udevtrigger. I'm not sure what's actually causing the
problem, but I certainly don't want this bugzilla to be sitting in a wrong
component.

Is there anything I can help with?

I think this should be moved to udev.

Seems like a problem with udev setting the selinux context again for symlinks.

Created attachment 301766 [details]
possible patch

Created attachment 301767 [details]
better patch

dwalsh, what context should the symlinks in /dev/disk have?

# ls -Z /dev/disk/*
/dev/disk/by-id:
lrwxrwxrwx  root root system_u:object_r:device_t       ata-QEMU_HARDDISK_QM00001
-> ../../hda

# ls -Z /dev/hda
brw-r-----  root disk system_u:object_r:fixed_disk_device_t /dev/hda

 SELinux is preventing /sbin/udevd (rpm_script_t) "create" to
ata-QEMU_HARDDISK_QM00001 (fixed_disk_device_t).

seems like we can't set the same context for the symlinks.

Created attachment 301781 [details]
final patch - backported from later versions

Symlinks should not be being set, the problem here is the block devices are
being mislabeled.  Symlinks should be device_t while block devices should be
labeled fixed_disk_device_t

I'm confirming that the patch from comment #20 solves the problem (udev built
locally, tested on RHEL5.2-Server-20080409.nightly / i386).

Giving Devel ACK as per comment #20 and comment #22.

Thanks,

Read ya, Phil

Verified with udev-095-14.15.el5 / RHEL5.2-Server-20080422.nightly

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2008-0374.html