Denied access to hidden file /media

Discuss usability issues, general maintenance, and general support issues for a grsecurity-enabled system.

Denied access to hidden file /media

Postby rom2mars » Thu Jun 05, 2014 8:23 am

Hello,

Sometimes, I have a problem, when I try to mount my usb key (error : denied access to hidden file /media by /bin/mount).

First, when I start RBAC I have this warning :

Code: Select all
[root@iKPA-Secure grsec]# gradm -E
Warning: In role shutdown subject /bin/bash, pathname "/etc/init.d/stopRbac.sh":
A writable and symlinked directory "/etc/init.d" points to "/etc/rc.d/init.d".
Warning: In role shutdown subject /etc/init.d/gradm, pathname "/etc/init.d/gradm":
A writable and symlinked directory "/etc/init.d" points to "/etc/rc.d/init.d".
Warning: object does not exist in role root, subject /etc/init.d/igc for the target of the symlink object /etc/init.d specified on line 1548 of /etc/grsec/policy.
Warning: object does not exist in role root, subject /bin/mount for the target of the symlink object /sys/dev/block/8:17 specified on line 1171 of /etc/grsec/policy.


Occasionally, I have this error when I try to mount usb key :

Code: Select all
Jun  5 13:35:57 localhost kernel: [86273.473450] grsec: (root:U:/bin/mount) denied access to hidden file /media by /bin/mount[mount:21406] uid/euid:0/0 gid/egid:0/0, parent /usr/bin/sudo[sudo:21399] uid/euid:0/0 gid/egid:500/500



My policy related to mount :

Code: Select all
# Role: root
subject /bin/mount o {
        /                               h
        /bin                            h
        /bin/mount                      rx
        /dev
        /dev/grsec                      h
        /dev/kmem                       h
        /dev/log                        h
        /dev/mem                        h
        /dev/null                       rw
        /dev/port                       h
        /dev/sdb1                       r
        /etc                            rwcdl
        /etc/grsec                      h
        /etc/gshadow                    h
        /etc/gshadow-                   h
        /etc/passwd                     h
        /etc/ppp                        h
        /etc/samba/smbpasswd            h
        /etc/shadow                     h
        /etc/shadow-                    h
        /etc/ssh                        h
        /lib                            rxi
        /lib/modules                    h
        /media                          crdwrl
        /proc                           h
        /proc/filesystems               r
        /selinux
        /sys                            h
        /sys/dev/block/8:17
        /sys/devices                    r
        /usr                            h
        /usr/lib                        rxi
        /usr/share                      h
        /usr/share/locale               r
        -CAP_ALL
        +CAP_SYS_ADMIN
        bind    disabled
        connect disabled
        sock_allow_family unix inet
}


Also I have other errors :

Code: Select all
Jun  5 13:38:50 localhost kernel: [86446.735349] grsec: (romain:U:/home/romain/Bin/Compilateur) denied access to hidden file /tmp by /home/romain/Bin/Compilateur[Compilateur:21588] uid/euid:500/500 gid/egid:500/500, parent /bin/bash[bash:13895] uid/euid:500/500 gid/egid:500/500

Jun  5 13:39:59 localhost kernel: [86515.605296] grsec: (romain:U:/home/romain/Bin/Compilateur) denied access to hidden file /home by /home/romain/Bin/Compilateur[Compilateur:21603] uid/euid:500/500 gid/egid:500/500, parent /bin/bash[bash:13895] uid/euid:500/500 gid/egid:500/500


However I have this policies :

Code: Select all
# Role: romain
subject /home/romain/Bin/Compilateur o {
        /                               h
        /dev                            h
        /dev/urandom                    r
        /etc                            h
        /etc/ld.so.cache                r
        /etc/localtime                  r
        /home
        /home/romain                       rxwcd
        /lib                            rx
        /lib/modules                    h
        /proc
        /proc/bus                       h
        /proc/kallsyms                  h
        /proc/kcore                     h
        /proc/modules                   h
        /proc/sys                       h
        /tmp                            cdrwx
        /usr                            h
        /usr/lib                        rx
        /var                            h
        /var/log/romain                    rw
        /var/tmp                        rw
        -CAP_ALL
        bind    disabled
        connect disabled
        sock_allow_family unix inet
}


Thanks in advance for your help,

Sorry for my english.

Regards,
Romain
Last edited by rom2mars on Fri Jun 06, 2014 3:02 am, edited 1 time in total.
rom2mars
 
Posts: 16
Joined: Fri Feb 07, 2014 10:52 am

Re: Denied access to hidden file /media

Postby spender » Thu Jun 05, 2014 11:24 am

Runtime mounting is not currently supported under RBAC.

For the other error, the log clearly shows the error being involved with the "igc" role, but you pasted policy from the role "romain".

-Brad
spender
 
Posts: 2185
Joined: Wed Feb 20, 2002 8:00 pm

Re: Denied access to hidden file /media

Postby rom2mars » Wed Jun 11, 2014 5:07 am

Thank you for your reply.

I understand, the user will disable RBAC when he need to use usb key. Or I will create a script which : disable Rbac, mount usb key, and enable Rbac.


For the other error, I'm embarrassed, I have introduce when I wrote this message.

For confidential reason I must replace rôle name.

For this reason I have corrected my previous post.
Sorry for my english.

Regards,
Romain
rom2mars
 
Posts: 16
Joined: Fri Feb 07, 2014 10:52 am


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