Messages in this thread | | | Date | Fri, 02 Jul 1999 18:39:34 +0200 | From | "Dirk W. Steinberg" <> | Subject | Re: Serial Port COM1 under Linux on IBM ThinkPad 770X |
| |
Alan Cox wrote: > > > 0 crw-rw---- 1 root dialout 4, 64 Feb 23 04:42 /dev/ttyS0 > > 0 crw-rw---- 1 root dialout 4, 65 Feb 23 04:42 /dev/ttyS1 > > root@ibmtop:pts/0 ~ # cu -l /dev/ttyS0 > > cu: open (/dev/ttyS0): Permission denied > > cu: /dev/ttyS0: Line in use > > zsh: 5731 exit 1 cu -l /dev/ttyS0 > > > > >From strace cu: > > open("/dev/ttyS0", O_RDWR|O_NONBLOCK) = -1 EACCES (Permission denied) > > > > But this is as superuser (root). How is this possible at all? > > cu is setuid to uucp on some systems. Unless you have a deep desire to > inflict cu on yourself in the name of tradition try playing with minicom. > If you want to suffer cu then chmod it so its not setuid uucp
root@ibmtop:pts/0 ~ # ll =cu 120 -rwxr-xr-x 1 root root 121156 Apr 21 22:22 /usr/bin/cu*
The cu binary is from Debian 2.2 (potato)
root@ibmtop:pts/0 ~ # dpkg -S =cu uucp: /usr/bin/cu
As you can see, cu is not suid root. But you were still right in a sense:
root@ibmtop:pts/0 ~ # strace cu -l /dev/ttyS0 |& grep setuid setuid(10) = 0
Uid 10 is uucp. I do consider this strange behaviour.
Anyway, I prefer a simple command line tool like cu to a menu-driven thing like minicom.
All of this still doesn't solve my problem, though.
Thanks for the help, anyway,
Dirk
-- Dipl.-Ing. Dirk W. Steinberg __________________________________________________ Consultant Technologieberatung Informationssysteme DETECON GmbH, Oberkasseler Strasse 2, 53227 Bonn Tel.: (0228) 700-1277 Fax: (0228) 700-1157 Mobil: (0171) 221 6585 Internet: www.detecon.de
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |