Re: Weird behavior with /dev/mem

On Fri, 31 Oct 2003, Daniel C. Sobral wrote:

> Weird thing. I updated my system today (October 31), and now I can't
> list routes from syscons. But I still can list routes from Konsole, on
> X. Following a suggestion by Genesys, I checked permissions of /dev/mem
> and netstat and... for some reason, I can't stat /dev/mem under syscons!

You didn't mount that filesystem nosuid, did you?

> Here are a couple of typescripts I got:
>
> [0] dcs_at_dcs:/opt/home/dcs$ cat from_konsole
> Script started on Fri Oct 31 17:25:04 2003
> dcs_at_dcs:/opt/home/dcs$ ls -ld /dev
> dr-xr-xr-x  4 root  wheel  512 Oct 31 13:56 /dev
> dcs_at_dcs:/opt/home/dcs$ ls -l /dev/mem
> crw-r-----  1 root  kmem    2,   0 Oct 31 15:54 /dev/mem
> dcs_at_dcs:/opt/home/dcs$ ls -l /usr/bin/netstat
> -r-xr-sr-x  1 root  kmem  108664 Oct 31 13:18 /usr/bin/netstat
> dcs_at_dcs:/opt/home/dcs$ netstat -nr
> Routing tables
>
> Internet:
> Destination        Gateway            Flags    Refs      Use  Netif Expire
> default            10.0.11.1          UGSc        0        0   fxp0
> 10/16              link#1             UC          0        0   fxp0
> 10.0.2.72          00:04:23:2a:13:7b  UHLW        0        1   fxp0    881
> 10.0.11.1          00:10:54:cd:58:40  UHLW       28        0   fxp0   1197
> 10.0.12.131        00:01:30:26:e0:00  UHLW        0        0   fxp0   1186
> 10.0.14.20         00:02:55:58:22:0a  UHLW        6    39928   fxp0    975
> 127.0.0.1          127.0.0.1          UH          0        6    lo0
> dcs_at_dcs:/opt/home/dcs$ exit
> exit
>
> Script done on Fri Oct 31 17:25:20 2003
> [0] dcs_at_dcs:/opt/home/dcs$ cat from_syscons
> Script started on Fri Oct 31 17:26:01 2003
> root_at_dcs:/root$ ls -ld /dev
> dr-xr-xr-x  4 root  wheel  512 Oct 31 13:56 /dev
> root_at_dcs:/root$ ls -l /dev/mem
> ls: /dev/mem: Permission denied
> root_at_dcs:/root$ ls -l /usr/bin/netstat
> -r-xr-sr-x  1 root  kmem  108664 Oct 31 13:18 /usr/bin/netstat
> root_at_dcs:/root$ netstat -nr
> netstat: kvm not available
> Routing tables
> rt_tables: symbol not in namelist
> root_at_dcs:/root$ exit
> exit
>
> Script done on Fri Oct 31 17:26:18 2003
> [0] dcs_at_dcs:/opt/home/dcs$ which ls
> /bin/ls
> [0] dcs_at_dcs:/opt/home/dcs$ type ls
> ls is aliased to `ls -G'
> [0] dcs_at_dcs:/opt/home/dcs$ unalias ls
> [0] dcs_at_dcs:/opt/home/dcs$ ls -l /dev/mem
> crw-r-----  1 root  kmem    2,   0 Oct 31 15:54 /dev/mem
>
> I'm CCing phk on the grounds of Mr Devfs, and Sam as I blamed the
> networking code earlier... :-)
>
>

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite_at_gumbysoft.com          |  www.FreeBSD.org